Mutagenesis by tritium: decays originating from growth and storage in tritiated water and from chemostatic growth in the presence of tritiated nucleic acid precursors.


House approves plan for dental services under Medicaid.


Helium-rebreathing method for the determination of FRC and RV.


Investigations on the biosynthesis of steroids and terpenoids. VI. The sterols of yeast.


Roster of Mississippi dentists.

Roster of Mississippi dentists.


Evaluation of the infertile patient. A review and a proposed plan of study.


Postoperative pulmonary insufficiency after open heart surgery and changes in pulmonary surface activity.


MSI and MSII made on ribosome in idling step of protein synthesis.


Morphine physical dependence unaltered by previous dependence on morphine.


Interferon inhibits viral protein synthesis in L cells infected with vaccinia virus.


Effect of copper on the preimplantation mouse embryo.


New antifertility agent--an orally active prostaglandin--ICI 74,205.


Origin of amniotic fluid group-specific component.


Culture of rabbit blastocyst in a medium with a convection current.


Do membrane filters prevent cell contacts?


Voluntary control of smooth eye movements and their velocity.


Will a large complex system be stable?

Will a large complex system be stable?


Stages in colicin K action, as revealed by the action of trypsin. The effects of trypsin on Escherichia coli cells that have been treated with colicins have been examined. By the use of trypsin, it has been possible to demonstrate that the action of several colicins (E1, E2, and K) proceeds through at least two stages. Stage I is a period after colicin adsorption when trypsin can restore colony-forming ability to a colicin-treated cell. Stage I is followed by a period when trypsin is unable to restore colony-forming ability (stage II). The transition between stage I and stage II follows first-order kinetics, with a rate proportional to the number of killing units of colicin adsorbed.A quantitative comparison of the effects of colicin K on colony-forming ability and on several cellular processes indicates that colicin damage to these processes occurs in the stage II period of colicin action and is not subject to reversal by the trypsin treatment that restores viability to cell in stage I. The implications of these findings for an understanding of the mode of action of colicins are discussed.


The stabilization of episomal integration by genetic inversion: a general hypothesis. In F' cells of Escherichia coli K12, recombination in the region of genetic duplication between chromosome and F-genote produces a rapid alteration between the integrated and detached states of the episome. Nevertheless, F' strains can give rise to Hfr cells in which the F-genote has undergone stable integration. We have found that one such Hfr has retained the genetic duplication as well as the recombination proficiency of the parental F' strain; to account for the failure of recombination to detach the episome in this Hfr, we have postulated the inversion of one of the duplicated regions. A general model is presented, showing that an inversion must prevent episome detachment by any combination of genetic crossovers.


Isolation and partial characterization of a mutant of Escherichia coli deficient in DNA polymerase II. A mutant of Escherichia coli deficient in DNA polymerase II has been isolated from E. coli polA1 by mutagenesis with N-methyl-N'-nitro-N-nitrosoguanidine and assay of polymerase activity in extracts of survivors. The polA1 mutation was suppressed during mutagenesis by introduction of the suppressor, su7(+), into the parental strain. The mutant, HMS83 polA1 polB1, contains less than 0.5% of the normal levels of DNA polymerase II. The only polymerase activity detected in the mutant is DNA polymerase III. E. coli HMS83 grows normally at both 25 and 42 degrees , and supports the growth of bacteriophages T4, T7, lambda, varphiX174, 186, P2, and fd. The polB mutation does not affect sensitivity to ultraviolet irradiation or recombination frequencies.


Nonchromosomal antibiotic resistance in bacteria: genetic transformation of Escherichia coli by R-factor DNA. Transformation of E. coli cells treated with CaCl(2) to multiple antibiotic resistance by purified R-factor DNA is reported. Drug resistance is expressed in a small fraction of the recipient bacterial population almost immediately after uptake of DNA, but full genetic expression of resistance requires subsequent incubation in drugfree medium before antibiotic challenge. Transformed bacteria acquire a closed circular, transferable DNA species having the resistance, fertility, and sedimentation characteristics of the parent R factor. Covalently-closed, catenated, and open (nicked) circular forms of R-factor DNA are all effective in transformation, but denaturation and sonication abolish the transforming ability of R-factor DNA in this system.


The effect of various nucleotides on the helical nature of a ribosomal protein(s) from Escherichia coli. In the presence of GTP or GDP, there is a decrease in the circular dichroic absorption of ribosomal proteins L(7) and L(12) at 221-222 nm, suggesting that these nucleotides influence the helical content of these proteins.


The attachment site of streptomycin to the 30S ribosomal subunit. The 16S RNA dissociated from 30S ribosomal subunits of Escherichia coli strains either sensitive or resistant to streptomycin contains the attachment sites for two streptomycin molecules, as does the undissociated particle from a streptomycin-sensitive strain. Since no streptomycin binds to undissociated 30S subunits from a streptomycin-resistant strain, it is suggested that protein P10, specified by the strA locus-known to be responsible for drug sensitivity-controls the availability to streptomycin of the attachment sites. These sites remain exposed in the strA(+) wild-type, and become masked in strA streptomycin-resistant mutants. The 16S RNA molecule binds streptomycin specifically; it binds two drug molecules in its native state, binds many more after its secondary structure is unfolded by melting out, and again binds two molecules after reannealing. The binding is stable to exhaustive dialysis, but it is reversed by exposure of the streptomycin-RNA complex to high-salt concentration. The complex can not be used to reconstitute functional ribosomes, but the 16S RNA reacquires this property after streptomycin elimination. The biological significance of this stable streptomycin binding is questioned, since in strA mutants exhibiting phenotypic masking, exposure to streptomycin induces a modified 30S behavior that persists even after streptomycin has been dialyzed away, and is reversed only by exposure of the modified RNA to high-salt concentration.


Inhibition of methylgalactoside transport in Escherichia coli upon the cessation of unsaturated fatty acid biosynthesis. The activity of the methylgalactoside transport system of E. coli is impaired upon treatment with 3-decynoyl-N-acetylcysteamine, an inhibitor of unsaturated fatty-acid synthesis. Treated cells are unable to be induced for permease activity, while transport sites synthesized before treatment show a regular loss of activity. The inhibition of methylgalactoside transport occurs at a step after translation of the galactose-binding protein, a component of the permease, and appears to be highly specific, since drug-treated cells show normal viability, protein synthesis, and membrane integrity when transport activity is greatly reduced. A second transport system, the galactoside permease, shows significantly less sensitivity to the inhibitor. That the activity of this permease is maintained in the presence of this inhibitor suggests that the inhibitor does not impair energy coupling.


Negative control of protein synthesis after infection with bacteriophage T7. T7 phage induces two negative control mechanisms of protein synthesis: (a) Host-gene expression is repressed by a "T7 repressor," and (b) early T7 protein synthesis is inhibited by a late phage protein.(a) The repressor for host enzyme synthesis is an early T7 protein. Its gene is none of the known early genes; it is located promotor-proximal to gene 1. The repressor function of this protein can be demonstrated by DNA-dependent enzyme synthesis in vitro.(b) Expression of early phage gene is depressed by a late phage protein or by T7 RNA polymerase. Control takes place on the level of transcription.


Coupling of replication to transcription in vitro. In a coupled system consisting of RNA polymerase and DNA polymerase I of Escherichia coli, the four deoxyribo- and the four ribonucleoside triphosphates, and DNA of bacteriophage f1 as template, DNA synthesis depends on the concomitant synthesis of RNA. Over a wide range of concentrations of the two polymerases, RNA synthesis was unaffected by the simultaneous synthesis of DNA, whereas the rate of DNA synthesis depended on the level of RNA synthesis. In the coupled reaction, RNA synthesis starts immediately at a high rate, which subsequently decreases, whereas DNA synthesis starts after a lag and its rate increases as the reaction proceeds. Upon addition of rifampicin, the rate of RNA synthesis falls abruptly, while that of DNA declines only gradually. The base composition of the DNA synthesized in the coupled reaction is complementary to that of f1 DNA template. It is suggested that the RNA synthesized by the RNA polymerase serves as a primer rather than as a template for the DNA polymerase.


Location of promoter and operator sites in the biotin gene cluster of Escherichia coli. Biotin independence in E. coli requires five closely linked genes, bioA, bioB, bioF, bioC, and bioD. The residual gene activity of deletion mutants has been studied by complementation and enzyme assays. Deletion of the left end of the bioA gene does not impair expression of the remaining genes, but deletions from the left extending into bioB abolish all gene expression. Nonsense mutations in bioB reduce expression of bioC, bioF, and bioD. Therefore, the four genes, bioB, bioF, bioC, and bioD, are transcribed as a unit from left to right, from a promotor located between bioA and bioB. Expression of the bio genes is repressible by added biotin. Deletions removing the left end of bioA do not affect repressibility of bioD. Therefore the operator, as well as the promoter, lie to the right of bioA. One deletion that removes bioA, bioB, and bioF renders the bioD gene constitutive, presumably by fusion to an unknown operon. Therefore, the operator lies to the left of bioC.


Stimulation of RNA synthesis by two protein factors in extracts of Escherichia coli. Two separate protein factors that markedly stimulate DNA-dependent RNA polymerase have been partially purified from ribosome-free extracts of E. coli Q13 cells. These proteins appear to differ from sigma, M, H, psi, and the factor described by Mahadik and Srinivasan. The stimulation by either factor requires the presence of the sigma protein. Using RNA-DNA hybridization competition analyses, we also demonstrate that neither of the new factors preferentially stimulates the synthesis of ribosomal RNA. The purification, properties, and mechanism of action of these new factors are examined.


GES-technique (cast precision attachment system). First practical experience with a technically improved precision attachment.


Clinical investigations and computer analysis of EEG effects of thioridazine hydrochloride on chronic schizophrenics.


Breathing mechanics and gas exchange in normal subjects during artificial ventilation. Influence of respiratory frequency and minute volume.


Central circulation during respirator treatment. Influence of respiratory frequency and minute ventilation.


Breathing mechanics during respirator treatment. Influence of respiratory frequency and minute volume.


The ultrastructure of pancreatic tissue from duct-ligated rats implanted into anterior chamber of rat eyes.


Our experience with the effect of placebos in some functional and psychosomatic disorders.


Effect of palmitoyl ethanolamide on alcohol intoxication in man.


An analysis of the acute effect of tetrahydrocannabinol (THC) and tobacco on verbal associations.


1972 membership roster of the American Association of Certified Orthoptists.


Orthoptics since Scobee (Richard G. Scobee).


A tribute to Julia Elizabeth Lancaster, 1896-1971.


Albert Darwin Ruedemann, Sr., 1897-1971.


Results of vaginal cultures taken during labour.


The utilization of L-tryptophan as nitrogen source by Fusarium culmorum, Aspergillus nidulans, and Penicillium italicum.


Purulent meningitis in newborn babies: observations and comments based on a series of 82 patients.


Preliminary characterization of a chlamydial agent isolated from embryonated snow goose eggs in northern Canada.


The neural crest origin of gastrointestinal and panceatic endocrine polypeptide cells and their distinction by sequential immunofluorescence.


Polyene macrolide derivatives. I. N-acylation and esterification reactions with amphotericin B.


Polyene macrolide derivatives. 3. Biological properties of polyene macrolide ester salts.


Antipain, a new protease inhibitor isolated from actinomycetes.


Non-thyroxine iodine release from the thyroid during acute malaria.


Metabolism of 15alpha-hydroxyestradiol in human pregnancy.


Human bone induction by allogeneic dentin matrix.


Some considerations on peripheral blood vessels in health and disease. A review.


The role of endotoxin in periodontal disease. IV. Bacteriologic analyses of human gingival exudate as related to the quantity of endotoxin and clinical degree of inflammation.


Porphyria in royalty.

Porphyria in royalty.


The Medical Society of Saint Elizabeths Hospital Historical Notes: 1937-1967.


Walter Freeman, M.D. 1895-1972.

Walter Freeman, M.D. 1895-1972.


Cryostat sections of embryos. Alternate serial sections for multiple histochemical reactions.


Change in the template specificity of RNA phage SP-replicase by the E. coli cell component.


HL-A and kidney transplantation.

HL-A and kidney transplantation.


Inhibition of minicircular DNA replication in Escherichia coli 15 by rifampicin.


Ampicillin resistance in Escherichia coli by phage infection.


Harry Draper Crofton, 1916-1972.

Harry Draper Crofton, 1916-1972.


Chromosomal locations of Salmonella conversion phages: mapping of prophages g 341, 15, and 34 in Salmonella anatum.


Structure and synthesis of a lipid-containing bacteriophage. XII. The fatty acids and lipid content of bacteriophage PM2.


Temperature-sensitive phenomenon of viral maturation observed in BHK cells persistently infected with HVJ.


Bacteriophage T4 transformation: an assay for mutations induced in vitro.


The rep mutation. II. Its effect on Escherichia coli and on the replication of bacteriophage phi X174.


A reanalysis of red-mediated reciprocal recombination in bacteriophage lambda.


Properties of polylysogens containing derepressed lambda N -  prophage: interference with the replication of superinfecting lambda.


Induction of lambda prophage by ultraviolet-irradiated Mu-1.


Infant feeding hygiene in Sweden. A survey of bottle and teat hygiene.


Antibodies in human milk against E. coli of the serogroups most commonly found in neonatal infections.


The prognosis of untreated and of treated hypertension and advantages of early treatment.


Aztec and Maya public health and preoptometry in Mexico.


Vergence breaks with a stepping prism.

Vergence breaks with a stepping prism.


Radioisotopic blood volume and cardiac output in dogs.


Sulfolobus: a new genus of sulfur-oxidizing bacteria living at low pH and high temperature.


Defects of ocular motility after stereotactic midbrain lesions in man.


Treatment of essential blepharospasm with a frontalis sling.


The blindness of Saint Paul.

The blindness of Saint Paul.


Stereotaxic intraocular surgery. Use in vitreous and posterior segment surgery.


Evaluation of the residual ridge and denture design in relation to the lateral force distribution to the abutment teeth. In the case of unilateral extension saddle type removable partial denture prosthesis.


Localization of the glial fibrillary acidic protein in astrocytes by immunofluorescence.


Comparison of bitoscanate (Joint) and tetrachlorethylene in treatment of Necator americanus infection.


Glucono- -lactonase from Saccharomyces cerevisiae: extraction, purification and characterization.


Spread of seizure discharges in epilepsy: anatomical and electrophysiological considerations.


An effective reactivation of alkaline phosphatase in hard tissues completely decalcified for light and electron microscopy.


Comparison of the hypnotic effectiveness of secobarbital, pentobarbital, methyprylon and ethchlorvynol.


Induction of galactokinase in Saccharomyces cerevisiae: kinetics of induction and glucose effects. The induced synthesis of galactokinase and the repressing effects of glucose on this synthesis have been investigated in whole yeast cells rendered permeable by treatment with dimethyl sulfoxide. It was found that the induction response of uninduced cells to galactose is clearly dependent on the nature of the carbon source upon which the culture was grown prior to exposure to galactose. Glucose-grown cells exhibited a long lag before induction, whereas lactate-grown cells exhibited induced synthesis within 8 min. A concentration of 0.5% galactose was found to be optimal for induction. The addition of glucose to yeast cultures growing on galactose resulted in a severe transient repression of synthesis which was followed by a resumed rate of synthesis characteristic of a weaker permanent catabolite repression. Neither 2-deoxygalactose nor fucose acted as gratuitous inducers of the pathway, nor did they serve as a substrates for galactokinase.


Integration stie of noninducible coliphage 186. From conjugational data, the attachment site for noninducible coliphage 186 (att186) was located between the origins of Hfr strains KL16 and KL98, and close to the pheA gene in Escherichia coli K-12. P1 transductions indicated that att186 lies at 51 min on the standard genetic map of E. coli, with the order cysC-nalB-att186-pheA. The presence of prophage 186 in the donor destroyed linkage between nalB and pheA, which is taken as evidence for the integration of the 186 prophage between these genes.


Partial characterization of phosphoribosyl transferase, phosphoribosyl anthranilate isomerase, and indole glycerol phosphate synthase from Serratia marcescens. The molecular organization of the enzymes phosphoribosyl (PR) transferase, phosphoribosyl anthranilate (PRA) isomerase, and indole glycerol phosphate (InGP) synthase of the tryptophan biosynthetic pathway of Serratia marcescens was investigated and compared with that reported in other enteric bacteria. PRA isomerase and InGP synthase activities were found to reside in a single polypeptide chain, a situation analogous to that in Escherichia coli, Salmonella typhimurium, and Aerobacter aerogenes. This bifunctional enzyme was purified to near homogeneity. Its molecular weight was estimated to be 48,000. PR transferase was found unassociated with PRA isomerase and InGP synthase after gel filtration and ion-exchange chromatography. Whereas in other enteric organisms PR transferase has been reported to form an aggregate with anthranilate synthase, it is a distinct entity in S. marcescens.


Ecology of sulfur-oxidizing bacteria in hot acid soils. Hot acid soils in Yellowstone National Park are rich in elemental sulfur and harbor extensive populations of sulfur-oxidizing bacteria. Thiobacillus thiooxidans is found at temperatures below 55 C, and at temperatures from 55 to 85 C Sulfolobus acidocaldarius is present. The distribution of these bacteria as a function of temperature was measured by a most-probable-number dilution method, and their activity in situ was assessed by use of a new technique permitting measurement of (14)CO(2) fixation. From these data it is concluded that sulfur-oxidizing bacteria are responsible for production of sulfuric acid in these acidic thermal habitats. Physical and chemical parameters of this unusual soil habitat were also measured and are described.


Mannitol sensitivity.

Mannitol sensitivity. The addition of mannitol to cultures of Salmonella typhimurium mutants missing mannitol-1-phosphate dehydrogenase causes stasis or lysis. Mannitol-1-phosphate accumulates intracellularly to concentrations of 20 mm. The incorporation of acetate into lipid is inhibited before cell wall, protein, or nucleic acid synthesis.


Location of trpR mutations in the serB-thr region of Salmonella typhimurium. Tryptophan biosynthesis in Salmonella is controlled by at least one regulatory gene, trpR, which is cotransducible with thr genes and not with the trp operon. Mutations in trpR cause derepression of tryptophan enzyme synthesis and confer resistance to growth inhibition by 5-methyltryptophan. Nineteen trpR mutations were mapped with respect to thrA and serB markers by two-point (ratio) and three-point transduction tests. The results are all consistent with the site order serB80-trpR-thrA59 on the Salmonella chromosome. Very low or undetectable levels of recombination between different trpR mutations have so far prevented the determination of fine structure in the trpR gene. Thirteen other 5-methyltryptophan-resistant mutants previously found not to be cotransducible with either the trp operon or thrA, and designated trpT, were also used in these experiments. Lack of cotransducibility with thrA was confirmed, and no linkage with serB was detected. The nature and location of trpT mutations remain obscure.


R factor elimination during thymine starvation: effects of inhibition of protein synthesis and readdition of thymine. R factor 1818 is shown to be eliminated from a thymineless strain of Escherichia coli J6-2 (R-1818) during thymine starvation. Readdition of thymine to the starved cultures produces a partial recovery in viable count but does not affect the proportion of R(-) cells. The R factor is not cured from exponential- or stationary-phase cultures which are starved of required amino acids as well as thymine, nor from cells which are deprived of thymine in the presence of chloramphenicol. However, in both of these cases, the extent of thymineless death is reduced. It is suggested that protein synthesis is a requirement for R-1818 elimination, and the possible nature of this protein is discussed.


Mutants of Salmonella typhimurium that are insensitive to catabolite repression of proline degradation. In Salmonella typhimurium the two enzymes of proline catabolism, proline oxidase and Delta(1)-pyrroline-5-carboxylic acid dehydrogenase, are subject to catabolite repression when the cells are grown in the presence of glucose. Mutants partially relieved of catabolite repression (PutR) for the proline catabolic enzymes have been isolated by selection on agar plates containing glucose and proline. The specificity of the catabolite repression-insensitive character for the enzymes of proline utilization has been confirmed by an analysis of other unrelated catabolic enzymes. Histidase and amylomaltase of the mutant strains are equally as sensitive to glucose repression as are the enzymes from the wild type. All four PutR mutants exhibit higher induced and higher basal levels of proline oxidase as compared with the corresponding wild-type levels. The mutations of three strains tested are cotransducible with constitutive, pleiotrophic-negative and structural gene mutations of the put region. Three-factor crosses indicate that two putR mutations are located at one end of the cluster of put mutations.


Characterization of strong polar mutations in a region immediately adjacent to the L-arabinose operator in Escherichia coli B-r. Seven l-arabinose-negative mutations are described that map in three genetically distinct regions immediately adjacent to the araO (operator) region of the l-arabinose operon. All seven mutants revert spontaneously, exhibit a cis-dominant, trans-recessive polarity effect upon the expression of l-arabinose isomerase (gene araA), and fail to respond to amber, ochre, or UGA suppressors. Three of these mutants exhibit absolute polarity and are not reverted by the mutangens 2-aminopurine, diethyl sulfate, and ICR-191. These may have arisen as a consequence of an insertion mutation in gene araB or in the initiator region of the l-arabinose operon. The four remaining mutants exhibit strong but not absolute polarity on gene araA and respond to the mutagens diethyl sulfate and ICR-191. Three of these mutants are suppressible by two independently isolated suppressors that fail to suppress known nonsense codons. Partially polar Ara(+) revertants with lesions linked to ara are obtained from three of the same four mutants. These polar mutants, their external suppressors, and their partially polar revertants are discussed in terms of the mechanism of initiation of expression of the l-arabinose operon.


Cell division and prophage induction in Escherichia coli: effects of pantoyl lactone and various furan derivatives. Strain T-44 is a thermosensitive mutant of Escherichia coli in which both cell division and prophage repression are altered at elevated temperatures. The effects of various ribosides, pantoyl lactone, and the furfural derivatives nitrofurazone and 5-methyl furfural suggest that some low-molecular-weight compound is important in the control of cell division and prophage repression in this strain. This low-molecular-weight compound may have a five-membered oxygen-containing ring as part of its structure.


Effect of cyclopentaneglycine on metabolism in Salmonella typhimurium. Cyclopentaneglycine (CPG) inhibited the growth of wild-type Salmonella typhimurium. The inhibition was overcome by isoleucine or any isoleucine precursor formed after threonine. CPG appeared to mimic isoleucine as a strong inhibitor of the activity of l-threonine deaminase. The analogue was a poor inhibitor of isoleucyl-transfer ribonucleic acid synthetase. CPG did not appear to be incorporated into protein nor did it replace isoleucine in repression. Cells that had recovered from growth inhibition by CPG had derepressed levels of the isoleucine-valine biosynthetic enzymes.


Response of the intracellular adenosine triphosphate pool of Saccharomyces cerevisiae to growth inhibition induced by excess L-methionine. Yeast cells accumulate S-adenosyl-l-methionine (S-AM) when cultivated in the presence of l-methionine. Cell growth is inhibited by the addition of high concentrations of l-methionine. A number of investigators have attributed this to the depletion of adenosine triphosphate (ATP) as a consequence of the utilization of that mucleotide for S-AM formation. The cellular ATP pool of Saccharomyces cerevisiae was measured during growth inhibition caused by addition of excess l-methionine. Polyethylenimine thin-layer chromatography and subsequent autoradiography were used to quantitate the extracted ATP. Addition of l-methionine to a level of 5 mg/ml in a culture during exponential growth caused an increase in the doubling time of 40 to 50%. During this period, the cellular ATP level continued increasing normally and, as the cells entered stationary growth, receded to a level characteristic of an uninhibited stationary culture growth. After the addition of methionine, there was never an observed depletion of the ATP pool other than the normal fluctuation which occurs in an uninhibited culture. We have concluded that growth inhibition by excessive methionine does not result from limiting availability of ATP.


Isolation and characterization of 2-keto-3-deoxyoctonate-lipid A from a heptose-deficient mutant of Escherichia coli. A heptose-deficient mutant of Escherichia coli has been isolated and from it a glycolipid, consisting of lipid A and 2-keto-3-deoxyoctonate (KDO), has been extracted with diisobutylketone-acetic acid-water. Based on beta-hydroxymyristic acid, the extractable glycolipid accounts for a major portion of the total lipid A in this mutant. A glycolipid, purified from the lipid extract by a combination of silicic acid and Sephadex LH-60 chromatography, contains glucosamine, phosphate, KDO, acetyl groups, and fatty acids in the following molar ratios: 1:2:2:1.7:5. These components account for over 80% of the lipid by weight. The fatty acid pattern of the glycolipid is typical of lipid A, the major component being beta-hydroxymyristic acid. The lipid also contains an amino sugar which appears to be 4-amino-4-deoxyarabinose. With the use of an ion-exchange paper chromatographic technique, gram-negative bacteria can be rapidly screened for the presence of this glycolipid. The mutant is believed to have a leaky defect in either biosynthesis of heptose or its incorporation into lipopolysaccharide. The lipopolysaccharide from the mutant contains only about a third as much heptose, glucose, and galactose as the parent CR34, a K-12 derivative. Chemical analysis and phage typing suggest that CR34 contains an incomplete core polysaccharide devoid of glucosamine.


Mutations affecting the dissimilation of mannitol by Escherichia coli K-12. Mutants of Escherichia coli K-12 defective in the mannitol-specific enzyme II complex of the phosphoenolpyruvate phosphotransferase system (PTS) or lacking mannitol-1-phosphate dehydrogenase have been isolated. These mutants fail only to grow on mannitol. Growth of the dehydrogenase-negative mutant on casein hydrolysate can be abruptly inhibited by exposure to mannitol. A mutant with constitutive expression of both of these enzymes has also been isolated. All three mutations are clustered in a region represented at min 71 of the Taylor map. In a mutant with less than 5% of the activity of enzyme I of the PTS, both the enzyme II complex and the dehydrogenase remain inducible by mannitol. In the mutant defective in the enzyme II complex, mannitol is able to induce the dehydrogenase. Thus, mannitol, rather than its phosphorylated product, seems to be the inducer.


Regulation of homocysteine biosynthesis in Salmonella typhimurium. The regulation of the homocysteine branch of the methionine biosynthetic pathway in Salmonella typhimurium has been reexamined with the aid of a new assay for the first enzyme. The activity of this enzyme is subject to synergistic feedback inhibition by methionine plus S-adenosylmethionine. The synthesis of all three enzymes of the pathway is regulated by noncoordinate repression. The enzymes are derepressed in metJ and metK regulatory mutants, suggesting the existence of regulatory elements common to all three. Experiments with a methionine/vitamin B(12) auxotroph (metE) grown in a chemostat on methionine or vitamin B(12) suggested that the first enzyme is more sensitive to repression by methionine derived from exogenous than from endogenous sources. metB and metC mutants grown on methionine in the chemostat did not show hypersensitivity to repression by exogenous methionine. Therefore, it appears that the metE chemostat findings are peculiar to the phenotype of this mutant; such evidence suggests a possible role for a functional methyltetrahydrofolate-homocysteine transmethylase in regulating the synthesis of the first enzyme. Thus there appear to be regulatory elements which are common to the repression of all three enzymes, as well as some that are unique to the first enzyme. The nature of the corepressor is not known, but it may be a derivative of S-adenosylmethionine. metJ and metK mutants of Salmonella have a normal capacity for S-adenosylmethionine synthesis but may be blocked in synthesis or utilization of a corepressor derived from it.


Requirement for protein synthesis in rec-dependent repair of deoxyribonucleic acid in Escherichia coli after ultraviolet or X irradiation. Deprivation of amino acids required for growth or treatment with chloramphenicol or puromycin after irradiation reduced the survival of Rec(+) cells of Escherichia coli K-12 which had been exposed to either ultraviolet (UV) or X radiation. In contrast, these treatments caused little or no reduction in the survival of irradiated recA or recB mutants. The effect of chloramphenicol on the survival of X-irradiated cells was correlated with an inhibition of repair of single-strand breaks in irradiated deoxyribonucleic acid (DNA), previously shown to be controlled by recA and recB. In UV-irradiated cells no effect of chloramphenicol was detected on the repair of single-strand discontinuities in DNA replicated from UV-damaged templates, a process controlled by recA but not by recB. From this we concluded that inhibiting protein synthesis in UV or X-irradiated cells may interfere with some biochemical step in repair dependent upon the recB gene. When irradiated Rec(+) cells were cultured for a sufficient period of time in minimal growth medium before chloramphenicol treatment their survival was no longer decreased by the drug. After X irradiation this occurred in less than one generation time of the unirradiated control cells. After UV irradiation it occurred more slowly and was only complete after several generation times of the unirradiated controls. These observations indicated that replication of the entire irradiated genome was probably not required for rec-dependent repair of X-irradiated cells, although it might be required for rec-dependent repair of UV-irradiated cells.


Aminotransferase from a deletion mutant in the histidine operon. The imidazolylacetolphosphate:l-glutamate aminotransferase from the deletion mutant hisHB22 has been partially characterized. Although genetic studies have not yet shown the deletion to involve the structural information for this enzyme, physical studies indicate that an abnormal enzyme is produced. Evidence is presented which, together with previous data on the characterization of the enzyme, indicates that the catalytic integrity of the enzyme is intact, and that the low specific activity seen in cell extracts is due to formation of an enzyme which has a reduced coenzyme content. It is suggested that this reduced coenzyme content is due primarily to a reduced affinity of the enzyme (nascent or apo-) for its coenzyme, and that the coenzyme must be incorporated into the enzyme at the moment of synthesis for formation of a functional protein.


Mapping of a D-cycloserine resistance locus in escherichia coli K-12. The mutation conferring first-step resistance to d-cycloserine has been located at min 83 on the Escherichia coli K-12 genetic map.


Cell division mutations in the blue-green bacterium Agmenellum quadruplicatum strain BG1: a comparison of the cell wall. The peptidoglycan from two types of filamentous cell division mutants of Agmenellum quadruplicatum strain BG1 has been compared to that of the parent organism. Small variations in the total peptidoglycan composition on a dry-weight basis were found in the mutants. The reduced level of peptidoglycan in the serpentine mutant is consistent with a general decrease in the ratio of surface area to volume as compared to the parent organism. The increased peptidoglycan content in the septate mutant confirms previous ultrastructural observations of the greatly enlarged peptidoglycan septum between adjacent cells. A comparison of peptidoglycan composition and cross-linking in the two types of filamentous mutants of A. quadruplicatum and in drug-induced phenocopies suggests that structural alterations of the peptidoglycan are not involved in the apparent impairments of cellular division. Furthermore, data concerning the relative susceptibilities of the parent and mutants to antibiotics indicate that neither mutant exhibits a gross alteration of permeability.


Effects of fraction I from Yersinia pestis on phagocytosis in vitro.


Influenza immunization: field trial on a university campus.


Renal transplantation study of infarcted kidney as carriers of a hypertensive factor in the rat.


The effect of ventricular pacing rates on the left ventricular volumes.


Complications of gonococcal infection.

Complications of gonococcal infection.


Development of an experimental syphilis vaccine.


The diagnosis and treatment of infectious and latent syphilis.


Syphilis in pregnancy.

Syphilis in pregnancy.


Historic hospitals. The Nuri Hospital, Damascus.


Single, combined and sequential use of uracil mustard and prednisone in the treatment of lymphoreticular tumors.


Spontaneous and radiation-induced deletion mutations in Escherichia coli strains with different DNA repair capacities.


Method for preparing anaphase figures from rat bone marrow.


The variation in UV sensitivity of four K12 strains of Escherichia coli as a function of their stage of growth.


Observations on experimental mycotic mastitis in goats.


Prolongation of the survival of skin allografts by the injection of spleen cells in adult mice treated by antilymphocyte serum.


The influence of vitamin A on disease states.


Immunologic changes during specific treatment of the atopic state. IV. Blocking activity of isolated IgG, IgA, and IgM with a specific allergen-binding capacity.


Keratoplasty in keratoconus.

Keratoplasty in keratoconus.


Keratomycosis.

Keratomycosis.


Histopathologic observations of photocoagulated malignant melanomas of the choroid.


Measurement of intraocular pressure with a pneumatic applanation tonometer.


The significance of anterior synechiae after corneal transplantation.


Automated history taking in child psychiatry.


Acupuncture: ancient enigma to East and West.


The new face of legal psychiatry.

The new face of legal psychiatry.


In memoriam, Walter Freeman. 1895-1972.

In memoriam, Walter Freeman. 1895-1972.


Aspergillosis in four renal transplant recipients. Diagnosis and effective treatment with amphotericin B.


Combined anticholinergic agents and atropine-like delirium.


Recent advances in oncology.

Recent advances in oncology.


Solomon Berson on his work.

Solomon Berson on his work.


Gel filtration studies on the binding of peptides to pepsin.


Purification and properties of mitochondrial deoxyribonucleic acid dependent ribonucleic acid polymerase from ovaries of Xenopus laevis.


Mechanism of deoxyribonucleic acid degradation by an acid deoxyribonuclease from the snail Helix aspersa Müll.


Rate of chain breakage at apurinic sites in double-stranded deoxyribonucleic acid.


Inhibition of polyphenylalanine synthesis by supernatant fractions from pea seedlings at various developmental stages.


Modifications of ribonucleic acid by chemical carcinogens. Modification of Escherichia coli formylmethionine transfer ribonucleic acid with N-acetoxy-2-acetylaminofluorene.


The mechanism of action of initiation factor IF1: non-analogy with elongation factor EFTs.


Mitochondrial DNA from cytoplasmic petite mutants of yeast.


Determination of the degree of suppressivity of Saccharomyces cerevisiae strain RD I A.


The unusual properties of mtDNA from a "low-density" petite mutant of yeast.


Pyrimidine tract analysis of mtDNA from a "low-density" petite mutant of yeast.


Raman studies of nucleic acids. VI. Conformational structures of tRNA fMet , tRNA Val  and tRNA Phe  2 .


Specificities of tRNA methylases from mouse liver and plasmocytoma.


Temperature dependence of RNA-DNA hybridization kinetics.


Effects of a single, large, intravenous injection of dexamethasone.


Plasma endogenous triglyceride transport in hypertriglyceridaemia and effect of a hypolipidaemic drug (SU-13437).


Insulin and oral hypoglycaemic agents. I. Physiological and clinical pharmacological aspects.


Hemodialysis and renal transplantation in patients of the 50-80 age group.


Cardiovascular effects of delta-9-tetrahydrocannabinol in man.


Cephalexin: a review of its antibacterial, pharmacological and therapeutic properties.


Biochemical and genetic aspects of nystatin resistance in saccharomyces cerevisiae. Two phenotypically distinct sets of nystatin-resistant mutants were investigated. One set is resistant, respiratory competent, and requires no lipid for growth. The other set is more resistant, respiratory deficient, and lipid requiring (unsaturated fatty acid or sterol). Both sets show altered sterol composition as demonstrated by the Liebermann-Burchard colorimetric reaction, ultraviolet spectrophotometry, and gas-liquid chromatography. Genetic analysis indicates that all nystatin-resistant mutants can be placed into one of six distinct genetic groups. The phenotype's nystatin resistance, lipid requirement, and respiratory deficiency are recessive. There was one case of allelism for mutants from different sets. Revertants of mutants which have the tripartite phenotype retain a residual level of nystatin resistance, but they are no longer lipid requiring or respiratory deficient. Growth studies in mutants which have the tripartite phenotype reveal that the addition of ergosterol to the growth medium results in decreased resistance to nystatin.


Interference-contrast and phase-contrast microscopy of sporulation in clostridium thermosaccharolyticum grown under strict anaerobiosis. Cells of Clostridium thermosaccharolyticum grown under strict anaerobiosis (modified Hungate technique) were examined during growth and sporulation by employing Nomarski interference-contrast and Zernike phase-contrast optics to delineate the sequence of morphological changes leading to the formation of free, mature spores. A 0.5% l-arabinose, liquid, complex medium was used to obtain a yield of 30 to 40% free, refractile spores (ca. 10(8)/ml) by 48 hr of incubation. The mean doubling time for the glucose culture (vegetative cells) was found to be 80 min, and that for the l-arabinose culture (sporulating cells), 498 min. By 8 hr of incubation, beginning spore formation became evident in the arabinose culture by the development of a distinct arrowhead-shaped terminal swelling. By 32 hr of incubation or shortly thereafter, Nomarski optics showed the mature spore to be uniformly spherical, whereas the enlarged terminal swelling containing it was not. The use of phase-contrast and interference-contrast optics permitted the characterization of the distinctive morphological changes occurring during sporulation of C. thermosaccharolyticum.


Death through respiratory failure of a fraction of ultraviolet-irradiated Escherichia coli b-r cells. Escherichia coli B/r cells grown on a glycerol-containing medium and ultraviolet (UV)-irradiated to about 0.5% survival respire for about 1 hr and then cease for several hours. The cells that have completed repair and recovery processes begin to divide about 120 min after UV treatment, but this division is completely inhibited in liquid medium by caffeine, which delays repair of the irradiated deoxyribonucleic acid (DNA). When 5-fluorouracil (FU) is used to maintain respiration, the number of cells which form colonies when plated increases about 60-fold within 1 hr after irradiation. At least part of this increase does not involve repair while the cells are in the liquid medium because when caffeine is present there is still a 20-fold increase in colony formation. We conclude that many irradiated cells, although capable of carrying out complete and accurate repair of their DNA, die of respiratory failure; only when continuance of respiration is favored by FU treatment is their colony-forming potential realized. After an early increase, the number of cells able to form colonies in medium that contains FU remains constant while the completion of repair and recovery occurs. After these processes are completed, the number of cells able to form colonies increases slowly, except in the presence of caffeine, presumably because the late increase requires that repair steps take place while the cells are in liquid medium prior to cell division.


Kinetics of deoxyribonucleic acid destruction and synthesis during growth of Bdellovibrio bacteriovorus strain 109D on pseudomonas putida and escherichia coli. During the growth of Bdellovibrio bacteriovorus on Pseudomonas putida or Escherichia coli in either 10(-3)m tris(hydroxymethyl)aminomethane or in dilute nutrient broth, the host deoxyribonucleic acid (DNA) was rapidly degraded, and by 30 to 60 min after the initiation of the bdellovibrio development cycle essentially all host DNA became nonbandable in CsCl gradients. At this stage the host DNA degradation products were nondiffusable, and there was no appreciable pool of low-molecular-weight (cold acid soluble) DNA fragments in the cells or in the suspending medium. Bdellovibrio DNA synthesis occurred only after degradation of host DNA to a nonbandable form was complete. The synthesis occurred in a continuous fashion with P. putida as the host and in two separate periods with E. coli as host. By using E. coli containing a (3)H-thymidine label, it was shown that 73%, on the average, of the thymine residues of host DNA were incorporated into bdellovibrio DNA when E. coli was the only source of nutrient. In the presence of dilute nutrient broth, the host cells still served as the major source of precursors for bdellovibrio DNA synthesis, with only 20% of the precursors arising from the exogenous nutrients. The data indicate an efficient and controlled utilization of host DNA by the bdellovibrio. The host DNA is apparently degraded early in the developmental cycle to oligonucleotides of intermediate molecular weight from which the biosynthetic monomers are generated only as they become needed for bdellovibrio DNA synthesis.


Identification of two Saccharomyces cerevisiae cell wall mannan chemotypes. We have obtained evidence for two structurally and antigenically different Saccharomyces cerevisiae cell wall mannans. One, which occurs widely and is found in S. cerevisiae strain 238C, is already known to be a neutral mannan which yields mannose, mannobiose, mannotriose, and mannotetraose on acetolysis of the (1 --> 6)-linked backbone. The other, which was found in S. cerevisiae brewer's strains, is a phosphomannan with a structure very similar to that of Kloeckera brevis mannan. S. cerevisiae (brewer's yeast strain) was agglutinated by antiserum prepared against Kloeckera brevis cells. The mannan, isolated from a proteolytic digest of the cell wall of the former, did not react with S. cerevisiae 238C antiserum, whereas it cross-reacted strongly with K. brevis antiserum. Controlled acetolysis cleaved the (1 --> 6)-linkages in the polysaccharide backbone and released mannose, mannobiose, mannotriose, and mannotriose phosphate. Mild acid treatment of the phosphomannan hydrolyzed the phosphodiester linkage, yielding phosphomonoester mannan and mannose. The resulting phosphomonoester mannan reacted with antiserum prepared against K. brevis possessing monoester phosphate groups on the cell surface. alpha-d-Mannose-1-phosphate completely inhibited the precipitin reaction between brewer's yeast mannan and the homologous antiserum. Flocculent and nonflocculent strains of this yeast were shown to have similar structural and immunological properties.


Excision repair properties of isogenic rec mutants of Escherichia coli K-12. We have examined the excision repair properties of isogenic rec(-) and uvr(-) strains of Escherichia coli K-12. A recB(-)recC(-) strain excises dimers at a rate nearly that of the rec(+) parent, reaching the same extent of excision after a 1-hr postirradiation incubation. recA(-) and recA(-)recB(-) strains excise 75 to 80% of the dimers excised by their rec(+) parent, whereas a uvrB(-) strain excises no dimers during a 1-hr incubation. The doses of ultraviolet light (254 nm) required to reduce survival to 37% of the original population are 8 ergs/mm(2) for recA or recA recB mutants, 5 ergs/mm(2) for the uvrB(-) strain, 30 ergs/mm(2) for the recB recC mutant, and 230 ergs/mm(2) for the wild-type parent. From these data one cannot account for the ultraviolet light sensitivity of rec(-) strains on the basis of their excision repair properties. We conclude that rec gene products play no significant role in the early steps of excision repair. The assay we have used for excision of thymine dimers is a modification of the Carrier-Setlow technique, and is described in detail in the Appendix to this paper. To show the properties and validity of this method, results of experiments with thymine dimers formed in vitro and in vivo in E. coli K-12 are presented. These results show our method to be reproducible and sensitive to 0.005% of the total radioactive thymine present in thymine-containing dimers.


Mutants with altered glucose repression of amidase enzymes in Aspergillus nidulans. Aspergillus nidulans produces acetamidase and formamidase enzymes. The acetamidase is produced in reduced amounts during growth on glucose, whereas the formamidase is not greatly affected. Mutations in a gene, amdT, which affect glucose repression of amidases are described. One of these, amdT102, causes the acetamidase to be no longer subject to glucose repression and also affects ability to synthesize formamidase. The other, amdT19, results in both the formamidase and the acetamidase being subject to abnormally strong glucose repression, and also in increased maximal acetamidase activities. The dominance relationships at the amdT locus have been investigated. It is suggested that the amdT gene may play a positive role in controlling amidase synthesis.


Iron uptake in Salmonella typhimurium: utilization of exogenous siderochromes as iron carriers. Aerobic microorganisms have evolved a variety of siderochromes, special ligands which can dissolve insoluble ferric iron and facilitate its transport into the cell. We have found that enb mutants of Salmonella typhimurium blocked in the biosynthesis of enterobactin (its natural iron carrier) are able to utilize siderochromes of different types made by other microorganisms as iron carriers. The antibiotic albomycin delta(2) was used to select mutants defective in ferrichrome-mediated iron uptake. Twelve classes of albomycin-resistant mutants, named sid, were defined on the basis of their growth responses to other siderochromes. Most of these classes have genetic lesions in loci that are cotransduced with panC (represented at 9 min on the genetic map). The locus designated sidJ is cotransduced with enb, whereas sidK and sidL are linked with neither panC nor enb. Genetic and physiological data indicate that S. typhimurium has several transport systems of high specificity for a variety of siderochromes produced by other microorganisms.


Regulation of histidyl-transfer ribonucleic acid synthetase formation in a histidyl-transfer ribonucleic acid synthetase mutant of Salmonella typhimurium. Control of formation of the histidyl-transfer ribonucleic acid (tRNA) synthetase with an increased K(m) for histidine was studied in a hisS mutant of Salmonella typhimurium. Histidine restriction of both the hisS and hisS(+) strains resulted in a derepression of synthesis of histidyl-tRNA synthetase. When grown in a concentration less than the K(m) (100 mug/ml) of l-histidine, the hisS mutant maintained a higher level of histidyl-tRNA synthetase than the hisS(+) strain. Addition of excess amounts of l-histidine to the growth medium of the hisS mutant culture grown with 100 mug of l-histidine per ml resulted in a repression of histidyl-tRNA synthetase formation to equal that of the hisS(+) strain grown in 100 mug of l-histidine per ml. These data confirm previous findings that histidine tRNA is involved in the repression of synthesis of histidyl-tRNA synthetase.


Effect of thymine limitation of chromosomal deoxyribonucleic acid synthesis in Proteus mirabilis. The effects of thymine limitation on the rates of growth, deoxyribonucleic acid (DNA) synthesis, and increase in viable cell number for a thymine auxotroph of Proteus mirabilis were investigated. At thymine concentrations of 1.0 mug/ml and below, these rates were markedly decreased. After a reduction in thymine concentration from 10 mug/ml to 0.2 mug/ml, mass synthesis continued at the preshift rate for several hours. In contrast, the rate of DNA synthesis immediately decreased, resulting in a decrease in the DNA to mass ratio to about one-half of its normal level. Viable counts remained constant for several hours after the reduction in thymine concentration, and enlarged cells and multicellular "snakes" were formed. The rate of DNA synthesis was reduced at thymine concentrations below approximately 1.7 mug/ml. The addition of thymine to cultures which had been completely starved for thymine increased the rate of DNA synthesis to at least twice its normal value; this suggests that extra rounds of chromosome replication can be induced in P. mirabilis as previously observed in Escherichia coli.


Genetic transfer of Salmonella typhimurium and Escherichia coli lipopolysaccharide antigens to Escherichia coli K-12. Escherichia coli K-12 varkappa971 was crossed with a smooth Salmonella typhimurium donor, HfrK6, which transfers early the ilv-linked rfa region determining lipopolysaccharide (LPS) core structure. Two ilv(+) hybrids differing in their response to the LPS-specific phages FO and C21 were then crossed with S. typhimurium HfrK9, which transfers early the rfb gene cluster determining O repeat unit structure. Most recombinants selected for his(+) (near rfb) were agglutinated by Salmonella factor 4 antiserum. Transfer of an F' factor (FS400) carrying the rfb-his region of S. typhimurium to the same two ilv(+) hybrids gave similar results. LPS extracted from two ilv(+),his(+), factor 4-positive hybrids contained abequose, the immunodominant sugar for factor 4 specificity. By contrast, his(+) hybrids obtained from varkappa971 itself by similar HfrK9 and F'FS400 crosses were not agglutinated by factor 4 antiserum, indicating that the parental E. coli varkappa971 does not have the capacity to attach Salmonella O repeat units to its LPS core. It is concluded that the Salmonella rfb genes are expressed only in E. coli varkappa971 hybrids which have also acquired ilv-linked genes (presumably rfa genes affecting core structure or O-translocase ability, or both) from a S. typhimurium donor. When E. coli varkappa971 was crossed with a smooth E. coli donor, Hfr59, of serotype O8, which transfers his early, most his(+) recombinants were agglutinated by E. coli O8 antiserum and lysed by the O8-specific phage, Omega8. This suggests that, although the parental E. coli K-12 strain varkappa971 cannot attach Salmonella-specific repeat units to its LPS core, it does have the capacity to attach E. coli O8-specific repeat units.


Methionine adenosyltransferase and ethionine resistance in Saccharomyces cerevisiae. The methionine adenosyltransferase is repressed in Saccharomyces cerevisiae during growth in the presence of excess methionine. The relationship of this repression to the level of intracellular S-adenosylmethionine is discussed. In conjunction with these studies, an ethionine-resistant mutant has been investigated which has a low level of methionine adenosyltransferase under all conditions tested. The mechanism of ethionine resistance in the latter strain apparently depends on its inability to form large quantities of intracellular S-adenosylethionine. With respect to the methionine adenosyltransferase, there is no apparent interaction between ethionine-resistant and ethionine-sensitive alleles when both are present in the heterozygous diploid.


Antibody-mediated modification of the binding properties of a protein related to galactose transport. A galactose-binding protein related to the mglP transport system of Escherichia coli increases its affinity and binding capacity for the substrate when exposed to both d-galactose and specific antibodies. For this increase to occur, the binding protein has to be in contact with d-galactose for at least 2 min prior to the addition of the antibodies. This reaction was used to show that other substrates of the mglP transport system compete with galactose for a site(s) of the binding protein and that the degree of competition is comparable to that observed in vivo. A model for substrate translocation is presented postulating a cellular component that can induce conformational changes in the galactose-binding protein similar to those caused by antibodies.


Effects of treatment with sodium dodecyl sulfate on the ultrastructure of Escherichia coli. An electron microscopy study has been made of the effects of dissolution of the plasma membrane of Escherichia coli with sodium dodecyl sulfate (SDS) on the organization of the nucleoplasm and the cytoplasm. The alterations observed in time course experiments were related to absorbance changes and to release of macromolecules from the cells. As the cells became plasmolyzed, under the conditions used, the first visible effect of SDS was a collapse of the plasmolysis spaces. This was accompanied by a displacement of the nuclear material which then appeared in broad contact with the redeployed plasma membrane. This initial displacement of nuclear material to the cell border may indicate an association between the nucleoplasm and the plasma membrane. Upon further dissolution of the plasma membrane, the nuclear material receded from the cell margin and contracted into an axial filament. Meanwhile, the cytoplasm dissociated into an amorphous, Pronase-sensitive component and an electron-opaque, granular one sensitive to ribonuclease. The latter represented one continuous area of ribosomal structures surrounding the nucleoplasm, an organization which did not occur when the cells were inhibited with rifamycin before SDS treatment. During prolonged SDS interaction, approximately 65% of the cellular protein, 25% of the ribonucleic acid and 40% of the deoxyribonucleic acid were released from the cells concomitant with the disappearance of the amorphous cytoplasmic part, expansion of the ribosomal aggregate, and rearrangement of the nuclear material at the cell periphery. The observations support the contention that all ribosomal structures bear a direct relationship with the nucleoplasm.


Purification of sex pili from Escherichia coli carrying a derepressed F-like R factor. A procedure for the purification of sex pili is described. Escherichia coli K-12 carrying Rldrd19 was grown in nutrient broth and blended at the time of peak sex pilus production. The cells were removed by centrifugation, and the supernatant fraction was concentrated, dialyzed, and clarified in an ultrafiltration system. After an additional blend and a clearing spin, the material was centrifuged in a CsCl gradient, and the fractions containing the sex pili were subjected to isoelectric focusing. About 5 mg of intact pili of approximately 98% purity were obtained by this method from about 100 g (wet weight) of cells.


Yeast spheroplasts formed by cell wall-degrading enzymes from Oerskovia sp. Oerskovia sp. produces inducible extracellular enzymes which degrade the walls of various yeasts. Yeast spheroplasts are formed from both log- and stationary-phase cells.


Distribution of alkaline phosphatase within the periplasmic space of gram-negative bacteria. Both reaction-product localization and ferritin-coupled antibody studies have shown that alkaline phosphatase is evenly distributed throughout the peri-plasmic space of Escherichia coli and a marine pseudomonad. This space is not locally enlarged except in cases where plasmolysis has occurred.


Ribonuclease II activity in a "presumptive" ribonuclease II-deficient mutant. A mutant strain of Escherichia coli previously thought to possess low levels of ribonuclease II activity has normal levels of ribonuclease II after partial purification of this enzyme from crude extracts.


Sydney Limbrey Higgs. Eightieth birthday.


Escherichia coli mutants tht require either pyridoxine or alanine. Some pyridoxineless mutants of genetic group V grow to normal cell yields in glucose-salts medium containing 0.11 mm d- or l-alanine as the sole supplement.


Congenital elevation of the scapula.

Congenital elevation of the scapula.


A modified technique for stabilising the spastic thumb.


Hip instability in patients with myelomeningocele.


Pierre Lacroix. 1910-1971.

Pierre Lacroix. 1910-1971.


Cornelis Pieter Van Nes. 1897-1972.

Cornelis Pieter Van Nes. 1897-1972.


Raffaele Zanoli. 1897-1971.

Raffaele Zanoli. 1897-1971.


Boytcho Boytchev. 1902-1971.

Boytcho Boytchev. 1902-1971.


Evarts A. Graham, the American College of Surgeons, and the American Board of Surgery.


Unusual mental states in medieval Europe. I. Medical syndromes of mental disorder: 400-1100 A.D.


The development of the 'muscular sense' concept during the nineteenth century and the work of H. Charlton Bastian.


Immunity in 1890.

Immunity in 1890.


The author run mad. Etching published anonymously by Paul Sandby (1753).


Characterization of the virus of sialodacryoadenitis of rats: a member of the coronavirus group.


Analysis by gas chromatography of amines and nitrosamines produced in vivo and in vitro by Proteus mirabilis.


Effect of Escherichia coli endotoxin on temperature and sleep cycles of rats.


Detection of Haemophilus aphrophilus in the human oral flora with a selective medium.


An epidemic-associated episome?

An epidemic-associated episome?


Field dependence in manic-depressive patients.


Landmarks in the history of clinical psychology from its early beginnings through 1971.


A follow-up study of the CROS hearing aid.


Re-establishment of bronchial arteries after experimental lung lobe autotransplantation.


Genetic hearing loss with no associated abnormalities: a review.


Direct communication of the right pulmonary artery with the left atrium. A case report and review of the literature.


A new technique for repairing the major air passages.


Computerizing the blood smear report.

Computerizing the blood smear report.


Cerebral abscess--a recurrent otologic problem.


The "orienting reflex" as an input indicator in "subliminal" perception.


Gender identity, stress and psychological differentiation in figure-drawing choice.


Primary process elements in the Draw-A-Person protocols of creative young women.


Differing "creativities" in the wit and the clown.


Changes in serum free fatty acids during experimental live Escherichia coli septicemia.


Microflora of the gastrointestinal tract and the surgical malabsorption syndromes.


Localization of monoamine oxidase in rat liver mitochondria.


Cytochemical differentiation between monoamine oxidase and other neuronal oxidases.


Endometrial monoamine oxidase: the effect of sex steroids.


Ontogenetic development of monoamine oxidase.


Approaches to the catalytic mechanism of mitochondrial monoamine oxidase.


Selective inhibition of monoamine oxidase.


Multiple forms of mitochondrial monoamine oxidase.


Mechanistic aspects of the bovine hepatic monoamine oxidase reaction.


Ischemic heart disease and dietary fiber.


Fluorescein angiography and the retinal pigment epithelium.


Macular breaks. 1. Diagnosis, etiology, and observations.


Reactive reticulum cell hyperplasia of orbit, lacrimal gland, eyelids and conjunctiva.


Protection of penetrating corneal allografts from immune rejection.


Albert Darwin Ruedemann, Sr. 1897-1971.

Albert Darwin Ruedemann, Sr. 1897-1971.


Antoine Lacassagne, M.D. 1884-1971.

Antoine Lacassagne, M.D. 1884-1971.


Nuclear localization of immunoglobulins in renal biopsies of patients with lupus nephritis. Immunofluorescent evaluation of renal biopsies from 19 patients with lupus nephritis revealed nuclear localization of immunoglobulins (IgG and IgM) in 6 patients. Homogeneous, nuclear rim and speckled patterns of nuclear localization were observed. The extent of localization varied, with only occasional nuclei fluorescing in 1 case, whereas approximately 50% of the nuclei exhibited fluorescence in the most extreme case. The phenomenon of nuclear localization of immunoglobulins was not observed in immunofluorescent studies of 225 renal biopsies from patients with conditions other than lupus nephritis. The possibility that nuclear localization of immunoglobulins occurred artifactually in the 6 patients was considered and was discounted by determining antinuclear antibody titers on serum obtained concurrently with the renal biopsy Nuclear localization was not confined to areas of histologically evident parenchymal destruction, indicating that antinuclear antibodies do not react only with nuclear antigens after tissue breakdown, but may gain access to intracellular antigens prior to cell dissolution.


Orion Otis Feaster, M.D. 1893-1971.

Orion Otis Feaster, M.D. 1893-1971.


Altered phospholipid metabolism in a temperature-sensitive mutant of Escherichia coli, CR 34 T 46 .


Nineteenth century medical journalism in Texas: with a journal checklist. Texas medical journals prior to 1900 have been incompletely (sometimes incorrectly) recorded in periodical checklists. This paper attempts to provide a short account of the purposes and achievements of the more significant journals and to list all names and related name changes, in so far as it has been possible to do so.


The advent of printing as an obstacle to the development of rational medicine. At the time that printing came onto the scene in western Europe in the mid-1400s, the medical community was struggling in the depths of superstition, and little rational medicine was being practiced. With this new invention, a flood of ancient, outmoded texts was released upon the public, and eager readers frequently were unaware that books they were being sold as new works were actually in some cases a thousand years old. Added to this was the fact that the appearance in print of this irrational material lent credibility and authoritativeness to unscientific writings. Thus, in contrast to many other fields which were immeasurably helped by the advent of the printed book, rational medicine was in fact held back and prevented from developing for at least a full century. It was not until the Renaissance was well under way that important original contributions by such towering figures as Vesalius supplanted these worthless repetitions of ancient superstitions.


The Mount Sinai Hospital Library, 1883 to 1970. A history of the Mount Sinai Hospital Library in New York City from its inception in 1883 to 1970 is presented. From its modest beginnings the growth and development of the library is reviewed through eight decades. The paper reports the library's expanded role in the Mount Sinai School of Medicine of the City University of New York.


Helen Crawford. President, Medical Library Association, 1972-73.


A study of the first degree relatives of the parents of spina bifida children.


Nineteen hundred twenty-one in Toronto.

Nineteen hundred twenty-one in Toronto.


The insulin receptor.

The insulin receptor.


Molecular basis of insulin action: contributions of chemical modifications and synthetic approaches.


Insulin and proinsulin conformation in solution.


The changing profile and conditions surrounding clinical research in prisons.


Embryogenesis of the human pancreatic islets: a light and electron microscopic study.


Metabolic characteristics of isolated pancreatic islets in tissue culture.


Insulin secretion mechanisms and glucose metabolism in isolated islets.


Glucoreceptor mechanisms in islets of Langerhans.


The Deer Lodge Research Unit.

The Deer Lodge Research Unit.


The stimulus-secretion coupling of glucose-induced insulin release. IX. The participation of the beta cell web.


Practical developments in diabetes research.


The beta cell and its responses: summarizing remarks and some contributions from Geneva.


Observations on the relation of migraine and epilepsy. An electroencephalographic, psychological and clinical study using oral tyramine.


A study of pulvinar-cortical interaction in acute tungstic acid-induced epilepsy in the cat.


Preparation of subcellular fractions suitable for biochemical analyses from human subcutaneous adipose tissue obtained by needle biopsy. I. Isolation of mitochondria on a microscale.


Centripetal transport of attached particles on both surfaces of moving fibroblasts.


Microscopic characteristic of macroscopically normal non-syngeneic skin grafts.


Indirect evidence of two adverse components of the humoral response to skin allografts as revealed in ALS-suppressed mice.


Effect of Escherichia coli endotoxin on skin allografts in mice.


Academician Ivan Stanek is dead.

Academician Ivan Stanek is dead.


Ultrastructure of the ventral horns of the cervical intumescence of the albino rat after hypothermy.


Localization of the motor cells of the phrenic nerve of the cat.


Note on the functional morphology of the perivascular elements of the human epiphysis cerebri.


Microscopic structure and reactivity of muscular arteries as revealed by the freeze-drying method.


Morphological features of the desquamation process of cornified epidermal cells.


Studies on the anatomy and histology of the reproductive organs of Xenentodon cancila (Ham.).


Effect of trypan blue on growing chick embryo. II. Interference with function of the caudal morphogenetic system.


Carbon monoxide and methane production in rats, guinea pigs, and germ-free rats.


Structure of the borohydride reduction product of photolinked 4-thiouracil and cytosine. Fluorescent probe of transfer ribonucleic acid tertiary structure.


Concepts of residence time distribution applied to the indicator-dilution method.


Fritz Teal 1904-1971.

Fritz Teal 1904-1971.


Edward T. Haslam, M.D. 1915-1971.

Edward T. Haslam, M.D. 1915-1971.


Innominate osteotomy in Legg-Calvé-Perthes disease.


A threshold distribution hypothesis for packet storage of insulin and its mathematical modeling. Phases of insulin release were studied in the perfused pancreas during a variety of glucose stimulation patterns. Patterns included staircase stimulations, constant prolonged single steps, restimulations, and ramp functions. Except at low concentrations, prolonged single steps of glucose elicited early spikes of insulin and a slowly rising second phase. Total insulin in the initial spikes increased with higher glucose concentrations. However, the time-related pattern of these spikes was similar in all cases; ratios of initial secretion rate to total insulin released were constant. Total insulin released in this early phase approximated a sigmoidal function of glucose concentration; mathematical differentiation of this function gave a skewed bell-shaped distribution curve. Staircase stimulations caused insulin to be released as a series of transient spikes which did not correlate with the increment of glucose but rather to the available insulin for a given glucose concentration minus that released in previous steps. The sum of total insulin released as spikes in a staircase series leading to a given glucose concentration was the same as when that concentration was used as a single step. Interrupted prolonged glucose infusions indicated the second phase of insulin release could prime the pancreas and that the first and second phases were interrelated. When glucose was perfused as ramp functions of slow, increasing, concentration, phasic response disappeared.A previous two-compartmental model was expanded to include a threshold or sensitivity distribution hypothesis. This hypothesis proposes that labile insulin is not stored in a homogeneous form but as packets with a bell-shaped distribution of thresholds to glucose. These packets respond quickly when their threshold levels to glucose are reached or exceeded. Data from single step stimulations were utilized for constructing a mathematical model which simulated satisfactorily the various stimulation patterns.


Vital statistics of Triatominae (Hemiptera: Reduviidae) under laboratory conditions. I. Triatoma infestans Klug.


Studies of secretin-stimulated insulin responses in man. Recent studies have suggested that secretin, like glucose, stimulates a rapid insulin response from a small storage pool. In order to evaluate the mechanism of the secretin-stimulated insulin response, small (15 U) rapidly administered intravenous injections (pulses) of secretin were given before, during, and after a 20 hr 300 mg/min glucose infusion. Contrary to previous studies demonstrating that the acute insulin response to a small (5 g) pulse of glucose given 45 min after the start of the glucose infusion was significantly diminished compared to the response to the preinfusion pulse, the acute insulin response (2-5 min Deltaimmuno-reactive insulin muU/ml) to 15-U secretin pulses exhibited a greater than twofold increase (before: 31.1+/-15.4; during: 71.2+/-40.4, muU/ml, mean +/-SD, P < 0.02). The increased response to secretin was also found after 20 hr of continuous glucose infusion, but was not observed 1 hr after cessation of the infusion when plasma glucose levels returned to control values. Thus, this increased response to secretin was glucose dependent. Four 150-U secretin pulses given at 30 min intervals elicited progressively and significantly diminished acute insulin responses with each succeeding pulse, consistent with depletion of the small storage pool. Similar to the observation that the magnitude of the insulin response to secretin was glucose dependent, the glucose-stimulated output appeared to be secretin dependent. Thus the acute insulin response to 5 g glucose was increased after secretin pretreatment (presecretin: 34.9+/-14.8; postsecretin: 50.5+/-22.5 muU/ml. P < 0.02) which suggests that secretin may either enlarge the storage pool stimulated by glucose or increase its sensitivity. The effect of epinephrine and propranolol on acute insulin responses to secretin and glucose was also different. 15-U secretin pulses were unaffected by infusions of either epinephrine (pre: 31.6+/-17.9; during: 27.8+/-16.6 muU/ml) or propranolol (pre: 12.8+/-8.4; during: 10.7+/-5.5 muU/ml). The results of these studies indicate that although both glucose and secretin stimulate a rapid insulin response, these responses are easily differentiated. The data suggest that glucose and secretin stimulate functionally separate storage pools of insulin, but that the acute response to either stimulus is partly determined by exposure to the other.


Yellow fever epidemics of the late eighteenth century in Baltimore.


A fierce storm rages.

A fierce storm rages.


Academician Professor Nikolai N. Blokhin.


Effects of chronic prazepam administration on drug metabolism in man and rat.


Myelin figures associated with the cytoplasmic membranes in human medulloblastoma.


Computer-based consultation. Electrolyte and acid-base disorders.


Paradoxical embolism. Diagnosis during life.


Bacterial infection in renal homotransplant recipients. A study of fifty-three bacteremic episodes.


Salt-losing syndromes following renal transplantation.


Effects of prostaglandin E 1  on contralateral olivo-cochlear bundle stimulation in cats.


Translational and transcriptional components of repression by arginine in Escherichia coli.


II. The polymorphism of natural DNA.

II. The polymorphism of natural DNA.


Altered translational or transcriptional components of repression in argR mutants of Escherichia coli: evidence from a translation retarder.


On the biological activities of the synthetic tetrapeptide pyroglutamyl-tyrosyl-arginyl-tryptophanyl-amide.


Luteinizing hormone releasing factor. The total solid-phase synthesis on a benzhydrylamine polymer.


The preparation of rat liver high molecular weight mitochondrial RNA free of cytoplasmic ribosomal RNA.


Uptake of tetracycline by Escherichia coli: lack of binding of tetracycline to the uptake system.


Failure of fusidic acid and siomycin to block ribosomes in the pretranslocated state.


Localization within the heavy chain sequence of tyrosyl peptides from the combining sites in a rabbit anti-3-azopyridine antibody preparation.


Nucleotide sequence analysis of DNA. IX. Use of oligonucleotides of defined sequence as primers in DNA sequence analysis.


Preparation of undecalcified bone sections for auto- and microradiography.


The structure of some bivalve shell carbonates prepared by ion-beam thinning. A comparison study.


Long term effects of special class intervention for emotionally disturbed children.


Medicolegal contributions of historical interest. Case IV. Murder by suffocation.


Illinois State Dental Society membership directory 1972-73.


Analysis of alcohol. I. A review of chemical and infrared methods.


Analysis of alcohol. II. A review of gas chromatographic methods.


Review of methods of analysis for phenothiazine drugs.


A bibliography of references on the analysis of drugs of abuse.


Skin allografts in the newt, Notopthalmus viridescens: cessation of blood flow as an indicator of rejection.


Harry Gold, M.D., F.C.P., 1889-1972.

Harry Gold, M.D., F.C.P., 1889-1972.


Automatic computer analysis of digital dynamic radionuclide studies of the cerebral circulation.


Relative potency of trichlorofos compared to pentobarbital as a hypnotic.


Clinical trial of a new antianginal drug: perhexiline maleate.


John Parks, M.D., 1908-1972.

John Parks, M.D., 1908-1972.


Control of supraventricular premature beats with phentolamine.


Candida infection of the gastrointestinal tract.


Inhibition of the response to thermal injury by oral proteolytic enzyme.


Pharmacology of antihyperglycemic drugs.


Hodgkin's disease. Recent concepts in management.


Scalp lesions in early American art.

Scalp lesions in early American art.


Two studies of the effects of mesoridazine.


Henri Mondor, M.D. (1885-1962). Surgery and french letters.


Ultrasonic film echography in gynecology and obstetrics.


Cervical mucus, vaginal cytology and steroid excretion in recurrent abortion.


Guidelines for the management of patients with ovarian adenocarcinoma.


Folate metabolism.

Folate metabolism.


Bacterial colonization of the respiratory tract in hospitalized patients with malignant diseases.


48-hour kidney preservation (initial perfusion with potassium and magnesium-rich solution).


Behavioral changes of chronic schizophrenic patients given L-5-hydroxytryptophan. Oral administration of the serotonin precursor L-5-hydroxytryptophan with a peripheral decarboxylase inhibitor produced Mild to moderate improvement in six of seven chronic undifferentiated schizophrenic patients who were resistant to phenothiazine treatment, as compared to an oral administration of a placebo. Two of four chronic paranoid schizophrenic patients who were resistant to phenothiazine treatment became worse with 5-hydroxytryptophan, one improved. It is presumed that these psychological changes were directly or indirectly produced from increases in brain serotonin. Indirect data from animals and humans indicate that there may be an abnormality in serotonin metabolism in some schizophrenics. While our data are consistent with this hypothesis, other explanations for our data must be entertained.


Early development of the human laryngeal muscles.


Jacob DaSilva Solis-Cohen, M.D. pioneer laryngologist.


Deletion mapping of zwf, the gene for a constitutive enzyme, glucose 6-phosphate dehydrogenase in Escherichia coli. Genes for three enzymes of intermediary sugar metabolism in E. coli, zwf (glucose 6-phosphate dehydrogenase, constitutive), edd (gluconate 6-phosphate dehydrase, inducible), and eda (2-keto-3-deoxygluconate 6-phosphate aldolase, differently inducible) are closely linked on the E. coli genetic map, the overall gene order being man... old... eda. edd. zwf... cheB... uvrC... his. One class of apparent revertants of an eda mutant strain contains a secondary mutation in edd, and some of these mutations are deletions extending into zwf. We have used a series of spontaneous edd-zwf deletions to map a series of point mutants in zwf and thus report the first fine structure map of a gene for a constitutive enzyme (zwf).


Salmonella typhimurium-Escherichia coli hybrids for the tryptophan region. Fifty-eight hybrids were analyzed for their phenotypic stability, presence and nature of cryptic trp alleles and by P22-mediated transduction to yield percent homologies. The hybrids fall into 5 distinguishable classes: a haploid class in which selected E. coli genes replace equivalent sites in the S. typhimurium chromosome; three merodiploid classes in which the selected E. coli genes are integrated at novel sites in the S. typhimurium chromosome-on the same transducing fragment as the female genes selected against, with or without cryptic damage to a nearby gene, or not on the same transducing fragment; and one class in which recombination has not taken place and the E. coli DNA is presumed to be an exogenote. The homology values are heterogeneous and do not permit an accurate determination of the relative frequency of incorporation of the integrated male genetic material. A further study of 20 hybrids indicates that genetic rearrangements can occur in the hybrids.


Nonsense mutation in the regulatory gene ETH2 involved in methionine biosynthesis in Saccharomyces cervisiae. Ethionine-resistant mutants, mapping at the locus eth2-the product of which is involved in pleiotropic regulation of methionine biosynthesis-have been isolated in a strain carrying five ochre nonsense mutations. Selection for nonsense suppressors in such a strain led to characterization of several allele-specific but gene non-specific suppressors which are active on the recessive heteroallele eth2-2 (resulting in partial recovery of sensitivity toward ethionine) as well as on the five other suppressible alleles. Two of these suppressors are unlinked to the eth2 gene and either dominant or semi-dominant. It is concluded that the mutation eth2-2 resulted in a nonsense codon. Enzyme studies indicate that this mutation results in a complete absence of an active product of gene eth2, in contrast with the effect of a former mutation eth2-1 which was interpreted as leading to a modified product of this gene (Cherest, Surdin-Kerjan and de Robichon-Szulmajster 1971). This conclusion is based on the absence of repressibility of methionine group I enzymes and the observation that in a heteroallelic diploid, eth2-1 expression is not masked by eth2-2. The nonsense suppressors studied lead to at least partial recovery of repressibility of methionine group I enzymes. All these results support the idea that the product of gene ETH2 is an aporepressor protein.


Interdigital butterfly flap (the double opposing Z-plasty).


Constant monitoring guarantees sterility.


Half a century of flexor-tendon surgery. Current status and changing philosophies.


Long-term follow-up of posterior iliopsoas transplantation for paralytic dislocation of the hip.


Valgus deformity of the ankle resulting from fibular resection for a graft in subtalar fusion in children.


Congenital elongation of the pedicles of the sixth cervical vertebra in identical twins.


The interfascicular nerve-grafting of the median and ulnar nerves.


Anterior interbody lumbar spine fusion. Analysis of Mayo Clinic series.


Revascularization and accretion in transplantation. Quantitative studies of the role of the allograft barrier.


Vinton Ernest Siler, 1909-1971.

Vinton Ernest Siler, 1909-1971.


The clonal nature of antibody formation. IV. Differential stimulation of antibody cell clones specific for poly-O-acetyl-D-serine and poly-D-alanine.


The lack of thymic influence in regulating the immune response to Escherichia coli 0127 endotoxin.


The immune response to sheep erythrocytes in the lizard Calotes versicolor.


Cell interactions in antibody formation in vitro. II. the interaction of the third cell and antigen.


Immunohistologic distribution of the chicken immunoglobulins.


Restrictive effects of thoracic burns in children.


The use of 0.5 percent silver nitrate in burns: results in 220 patients.


Achilles tendon rupture: pathogenesis, diagnosis, and treatment by a modified pullout wire technique.


Cosine method for analysis of indicator dilution curves.


Nephrotoxic serum nephritis in the rat: ultrastructural localization of nephrotoxic rabbit antibodies using peroxidase-labeled conjugates.


Role of the renal medulla in the sodium-sensitive component of renoprival hypertension.


Tamm-Horsfall mucoprotein. 3. Potassium dichromate-induced renal tubular damage.


Intracellular localization of pepsinogen in guinea pig pyloric mucosa by immunohistochemistry: histochemical and electron microscopic correlated structures.


Effects of viral infection on the developing nervous system.


Fluorides for multiple myeloma.

Fluorides for multiple myeloma.


Noise levels in pressure boxes.

Noise levels in pressure boxes.


Doctors' views of Medi-Cal.

Doctors' views of Medi-Cal.


Understanding hospitalized children through drawings.


How far do bacteria travel from the exhalation valve of IPPB equipment?


Academician Josef Charvát, founder of Czechoslovak endocrinology. 75th birthday.


New test of efficiency of pancreatic beta-cells and of carbohydrate metabolism.


The primary cause of rheumatoid arthritis is an infection--the infectious agent exists in milk.


Effect of unilateral electrocoagulation of the oculomotor nucleus on the ultrastructure of small multiple myoneural junctions present in the extraocular muscles.


Preliminary observations on the effect of a new benzodiazepine (RO 5-4023) in epilepsy.


Reticulum cell sarcoma of the breast--an autopsy case with terminal leukemic manifestation.


Induction of intracranial tumors in mice by human adenovirus type 12. 1. Immunofluorescent studies on T antigen and the predilection sites for tumor development in the brain.


Studies on mechanism of inhibition of L(+)lactate: cytochrome C oxidoreductase by phenothiazine drugs.


Route of endotoxin delivery; effects on canine mesenteric hemodynamics.


Field potentials evoked in rabbit brainstem by stimulation of the aortic nerve.


Lymphoidal involution and delayed homograft rejection in hypoxia-exposed mice.


Electron microscopic observations on division of the kinetoplast in Trypanosoma cruzi.


The membership of the Omaha district dental society 1972-73.


Bonded pin technic offers strong, safe retention.


Oral hygiene for denture patients.

Oral hygiene for denture patients.


Centrifugal casting of resin die material into copper ring impressions.


A survey of prosthetic technology in commercial dental laboratories. 1.


John R. Mannix. 1972 winner of the Justin Ford Kimball Award of the American Hospital Association.


Chromatographic methods in the analysis of protein structure. The methods for identification of N-terminal amino acids in peptides and proteins. Part B.


Chromatographic and biological aspects of the phthalate esters.


Ultrastructural development of explanted human skeletal muscle in tissue culture.


Quantitative cytochemical studies of RNA in experimental mercury poisoning. Changes in RNA content.


Anemias with renal transplantation.

Anemias with renal transplantation.


Properdin--its biologic importance.

Properdin--its biologic importance.


Solomon A. Berson.

Solomon A. Berson.


Careers extraordinary (Winifred Hector).


Initial evaluation and management of injuries to the soft tissue of the fingers.


Pesticides for plant protection in Norway: legislation, use, and residues.


Edgar Boling, M.D., Atlanta, Georgia, 1906-1972.


Production and cleaning of freeze-etch replicas which show complementary surfaces of fractured fungus spores and hyphae.


In situ embedding and vertical sectioning for electron microscopy of tissue cultures grown on plastic petri dishes.


Toluidine blue metachromasia: a means for early detection of plant virus infection.


Thin-layer epoxy embedding of filamentous plant parts for light and electron microscopy.


Vascular supply of human fetal adrenals and the functional significance of the microvascular patterns.


Myth of nitrogen equality in respiration: its history and implications.


Drugs affecting monoamines in the basal ganglia.


HL-A--transplantation antigens or genetic markers?


Practical schema for the identification of nonfermentative gram negative bacteria encountered in medical bacteriology.


Medium to aid identification of Serratia marcescens.


A positioning device for direct bracket attachment.


Bonding of clear plastic orthodontic brackets using an ultraviolet-sensitive adhesive.


A deflector catheter approach to the abdominal aorta.


Health in relation to geochemical environment. Animal requirements: basic and optimal.


Levodopa in Parkinson's disease: effect on pulmonary function.


Medical diagnosis: an information-processing approach.


Prolactin secretion in patients treated with various drugs: phenothiazines, tricyclic antidepressants, reserpine, and methyldopa.


Computer analysis of rest and exercise electrocardiograms.


On the normal use of reflexes.

On the normal use of reflexes.


Is computerized diagnosis possible?

Is computerized diagnosis possible?


Computer graphic techniques for study of temporal and spatial relationships of multidimensional data derived from biplane roentgen videograms with particular reference to cardioangiography.


Automatic boundary detection of the left ventricle from cineangiograms.


Continuous patient monitoring with a small digital computer.


Computer-aided evaluation of regional pulmonary function.


Prevention of pulpal damage.

Prevention of pulpal damage.


Hypophysectomy for diabetic retinopathy during pregnancy.


The prevention of tissue injury from removable partial dentures.


Aids to mobility for children with spina bifida and hydrocephalus.


Esophageal and colon changes in myotonia dystrophica.


Exfoliative cytology in gastric ulcer. Its role in the differentiation of benign and malignant ulcers.


Mechanism of polypeptide chain termination. Translation of tandem amber termination codons by an amber suppressor transfer ribonucleic acid.


Deoxyribonucleic acid synthesis in cell-free extracts. IV. Purification and catalytic properties of deoxyribonucleic acid polymerase III.


Escherichia coli strains with thermolabile ribonuclease II activity.


The amino acid sequence of  -galactosidase. II. Tryptic peptides of the maleylated protein and sequences of some tryptic peptides.


The amino acid sequence of  -galactosidase. 3. The sequences of NH 2 - and COOH-terminal tryptic peptides.


Mechanism of action of gonadotropin. II. Control of ovarian nuclear ribonucleic acid polymerase activity and chromatin template capacity.


Subtilisin Amylosacchariticus. II. Isolation and sequence of the tryptic and cyanogen bromide peptides.


Studies on termination of in vitro ribonucleic acid synthesis by rho factor.


Ridge augmentation with decalcified allogeneic bone matrix grafts in dogs.


Nuclear shaping in marsupial spermatids.


Free buccal mucosal grafts for vestibuloplasty.


Observations on the morphogenesis and structure of a hemocytic poxvirus in the midge Chironomus attenuatus.


ACS-NIH organ transplant registry. Second scientific report.


The tenth report of the human renal transplant registry.


Genetic and physiological factors relating to excision-repair in Escherichia coli.


Recombinational repair in UV-irradiated Escherichia coli.


Radiation and chemical mutagenesis and repair in mice.


DNA polymerases of Escherichia coli.

DNA polymerases of Escherichia coli.


The difference between DNA replication and repair.


Photoenzymatic repair of DNA. I. Investigation of the reaction by flash illumination.


Photoenzymatic repair of DNA. II. Physical-chemical characterization of the process.


Photoenzymatic repair in animal cells.

Photoenzymatic repair in animal cells.


Milbank memorial fund. April 1972.

Milbank memorial fund. April 1972.


Can feline oncornaviruses cause leukemia in man?


Renal biopsy. Indications and clinical value.


Chronic renal failure. Clinical and therapeutic considerations.


Renal transplantation--the changing scene.


Renal glomerular osteodystrophy.

Renal glomerular osteodystrophy.


The diagnosis of malacoplakia of the kidney by percutaneous renal biopsy.


Sieketroost: Dr James Barry's contribution to materia medica.


DuVal: giving the job of "top doctor" some substance.


Stereotaxic radiosurgery for cerebral arteriovenous malformations. Report of a case.


Wound infections after appendicectomy. I. A controlled trial on the prophylactic efficacy of topical ampicillin in non-perforated appendicitis. II. A controlled trial on the prophylactic efficacy of delayed primary suture and topical ampicillin in perforated appendicitis.


Early reactions in skin incisions in the rat. A thermographic, microangiographic and histologic study.


Erosion of the innominate artery. A complication following tracheostomy.


The branching pattern in dendrites of cortical neurons.


Electron microscopy of aspartate transcarbamylase and its catalytic subunit.


Limited production of R17 ribonucleic acid phage in the presence of rifampin.


Induced Cotton effects of tRNA-acridine orange complex and tRNA conformation.


Acylation of transfer ribonucleic acid with the N-hydroxysuccinimide ester of phenoxyacetic acid.


Structure and arrangement of the regulatory subunits in aspartate transcarbamylase.


The kinetics of the renaturation of deoxyribonucleic acid denatured in the presence of copper(II) ions.


Unusual laboratory exposure to a rabid skunk.


Effect of certain anesthetic agents on mallard ducks.


Proteus mirabilis infection in a mouse colony.


Enteropathogenic Escherichia coli infection in anthropoid apes.


Gravity as a factor in the animal environment.


Effect of light and behavior on nutrition.


Biological availability of fat-soluble vitamins: vitamin A and carotene.


Biosynthesis of prostaglandins.

Biosynthesis of prostaglandins.


Use of regression equations in predicting availability of energy and protein.


Hypothalamic and pituitary hormonal changes in rats injected with methylazoxymethanol acetate.


Bibliography of cycad research.

Bibliography of cycad research.


Enzymatic mechanisms of DNA replication in Escherichia coli.


Biological availability of minor mineral ions: a review.


Biological availability of nutrients in feeds: availability of major mineral ions.


IPPB, plasma ADH, and urine flow in conscious man.


Continuous positive-pressure ventilation and portal flow in dogs with pulmonary edema.


Pepsin digestibility method for animal proteins: 1971 collaborative study.


Immunologic stimuli in relation to leukemogenesis. 1. Potentiation of Rauscher viral leukemia by Freund's adjuvants.


Effect of immune factors on the motility of lymphoma cells.


Sir Isaac Newton.

Sir Isaac Newton.


The cadaver donor. Logistics of supply and demand in an urban population.


Boris Yegorov.

Boris Yegorov.


The number of physicians as a constraint on delivery of health care. How many physicians are enough?


Fetal heart rate monitoring during labor.


Bonding of alkyl 2-cyanoacrylates to human dentin and enamel.


A comparison of ketamine and methohexital in electroconvulsive therapy.


The relation of infantile autism and early childhood schizophrenia to developmental language disorders of childhood.


Leuman M. Waugh, 1877-1972 President of the IADR, 1926-1927.


Surgical treatment of advanced cases of proliferative diabetic retinopathy.


Photographic study of gold flow.

Photographic study of gold flow.


Retention of fluoride with chewable tablets and a mouthrinse.


Nosocomial infections due to kanamycin-resistant, (R)-factor carrying enteric organisms in an intensive care nursery.


Professor Bernardo A. Houssay (1887-1917).


A study of Salmonella typhimurium infection at a swine-testing station.


A study of human root cementum surfaces as prepared for and examined in the scanning electron microscope.


The lorenzinian ampullae of Polyodon spathula.


Contrasts in payment and provision of health care: Canada and the United States.


National health insurance and the poor.

National health insurance and the poor.


A silicone plastic cup for cutting corneal transplants.


Removal of immunoglobulin-bearing lymphocytes by anti-immunoglobulin-coated columns.


Homing of specifically sensitized lymphocytes to allografts of skin.


In vitro response of partially purified spleen cells: "blast" transformation.


Hydrogen and ascorbate dilution curves. A simplified method for routine use in detection of intracardiac shunt and valvular regurgitation.


Resuscitation experiments and breathing apparatus of Alexander Graham Bell.


Attachment of resin restorations to acid pretreated enamel.


Cellular immunity to nuclear antigens in systemic lupus erythematosus. Cellular immune repsonses were determined by skin testing and mitogen- and antigen-induced blastic transformation of peripheral blood lymphocyte cultures in 24 patients with systemic lupus erythematosus (SLE) and 24 normal subjects. The incidence of positive skin tests with Candida albicans, PPD (tuberculin-purified protein derivative) intermediate strength, Trichophyton and histoplasmin was not significantly different in the two groups nor was lymphocyte stimulation by the mitogen phytohemagglutinin-M (PHA-M), implying that cellular immunity is normal in SLE. However, the SLE patients had a significantly increased incidence of positive skin tests and stimulated lymphocyte cultures to a number of nuclear antigens compared with normal subjects. No correlation could be made between the test results and the activity of the SLE at the time of study except for a significant association between lymphocyte culture stimulation by rabbit thymus native DNA and active SLE nephritis. Patients with a membranous antinuclear factor (ANF) pattern had positive skin tests with rabbit thymus native DNA and usually had active disease.