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31.
13C NMR resonances of 15 simple tetrahydroisoquinolines have been assigned on the basis of chemical shift theory, 13C-1H coupling constants 相似文献
32.
Enhanced antibody response in the offspring of immunized rats 总被引:4,自引:0,他引:4
33.
Dr. C. C. Miller Dr. J. L. Gill Dr. L. D. McGilliard 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1971,41(3):130-135
Summary Linkage, dominance, and selection interact significantly to alter the mean coefficient of inbreeding. The effect of one is not predictable without the other two. Close linkage between adjacent loci in the presence of intense selection caused a different response with overdominant gene action from with partial dominance. When selection was random, effects of linkage and dominance on the coefficient of inbreeding were nonexistent; but when selection was by either phenotype or genotype, linkage and dominance became important. Joint effects between linkage, dominance, and selection are illustrated in specific simulated populations. 相似文献
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Chloroplast and cytoplasmic low-molecular-weight ribonucleic acid components of the leaf of Vicia faba L 总被引:5,自引:3,他引:2 下载免费PDF全文
1. A method for the extraction of plant nucleic acids and their separation on methylated-serum-albumin-kieselguhr columns is described. It is demonstrated that the characteristics of the elution profiles of material from the same source are consistently reproducible. 2. Major dissimilarities were found in the elution profiles of nucleic acids from root and from leaves of Vicia faba L. These dissimilarities were confirmed by polyacrylamide-gel electrophoresis. 3. Four distinct types of low-molecular-weight RNA were demonstrated to be present in leaves, clearly distinguished by their behaviour when chromatographed on methylated-serum-albumin-kieselguhr columns. (a) Both cytoplasmic and chloroplast ribosomes contained a low-molecular-weight RNA, and these components were distinct from each other. (b) The chloroplast possessed a unique ;soluble' RNA (i.e. RNA that is not precipitated by centrifugal forces that sediment ribosomes) which was not present in the rest of the cell. (c) A soluble component, probably transfer RNA, was found in both the chloroplasts and in the cytoplasm. 4. The components distinguishable by methylated-serum-albumin-kieselguhr column chromatography could not be distinguished by sucrose-density-gradient centrifugation. 相似文献
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Providing care for diabetics is difficult in prison. Six diabetic prisoners or former prisoners were seen whose care was difficult or unsatisfactory. Three had multiple admissions to hospital during their sentences with diabetic ketoacidosis that they induced themselves by not taking insulin. The motive seemed to be removal from prison to the fairly pleasant surroundings of the local hospital. A fourth prisoner required admission in a hyperglycaemic, hyperosmolar state that had gone unnoticed as he was thought to be "acting up." The two others had imperfect long term management of diabetes during their sentences. There is clearly room for improvement in diabetic services in British prisons, but manipulative behaviour on the part of some diabetic prisoners may remain a problem. 相似文献
38.
The recognition and investigation of an outbreak of food poisoning in 1982 due to chocolate contaminated with Salmonella napoli enabled the food that carried the salmonella to be identified and four fifths of the implicated consignment of chocolate to be withdrawn. The economic benefits of prompt intervention in the outbreak have been assessed. The cost of the outbreak was over 0.5 pounds m. It is estimated that five deaths were prevented by the intervention and that 185 admissions to hospital and 29,000 cases of S napoli enteritis were avoided. This successful investigation yielded a 3.5-fold rate of return to the public sector and a 23.3-fold return to society on an investment in public health surveillance. A methodology is described that can be used to estimate the benefits of early intervention in outbreaks of foodborne illness and topics for further research are suggested. It is concluded that public health authorities and industry have much to gain by collaborating in the research into the design of cost effective programmes to prevent foodborne infections. 相似文献
39.
After induction of experimental polymicrobic osteomyelitis with Staphylococcus epidermidis and Bacteroides thetaiotaomicron (ciprofloxacin MIC, 0.5 micrograms/ml and 4.0 micrograms/ml, respectively), in the presence of a foreign body implant, in a rabbit tibia model, ciprofloxacin was administered to infected animals for 2- and 4-week periods. At necropsy, rabbits in the 2-weeks-treated group had mean ciprofloxacin levels of 5.94 micrograms/ml in serum, 3.63 micrograms/g in marrow, and 1.88 micrograms/g in bone. Rabbits in the 4-weeks-treated group had mean ciprofloxacin levels of 7.77 micrograms/ml in serum, 5.84 micrograms/g in marrow, and 2.01 micrograms/g in bone. Quantitative bacterial plate counts were conducted on weighed samples of infected bone, marrow, and the catheter implant, taken at necropsy from treated and control rabbits. Variable reduction of bacterial numbers was observed in samples from treated animals, as compared to untreated controls. Samples of infected bone, marrow and catheter, showed comparable evidence of osteomyelitis and bacterial colonization in both treated and control animals. Although relatively high tissue levels of ciprofloxacin were attained, little therapeutic effect was observed. 相似文献
40.