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1.
Russian Journal of Genetics - Hemophilia A is a frequent X-linked recessive blood clotting disorder. It is caused by mutations in the F8 gene (locus Xq28) and affects 1 in 5000 newborn boys. The...  相似文献   
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The aim of the study was to evaluate sensitivity and specificity of positron emission tomography (PET) and 18F-fluorodesoxyglucose (18F-FDG) in breast cancer diagnosis and to assess tumor dissemination. Sixty two patients were examined: 10 without mammary disease, 10 with fibrous cystic mastopathy, and 42 with breast cancer, which was hystologically verified. PET scanning was recorded in the "Whole body" mode 70-90 min later administration of 370-420 MBq 18F-FDG. It was shown that PET has a high diagnostic accuracy in breast cancer detection. There were no False-positive cases in our investigations. PET scanning in the "Whole body" mode was allowed to assess dissemination of tumor process with high accuracy. Metastatic involvement of local lymph nodes was detected in 82.8% cases and bone metastases--86% in cases.  相似文献   
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It is discovered that chronic consumption of ethanol induced decrease of carboxypeptidase H activity in striatum by 27%; increase of carboxypeptidase M activity in hippocampus by 67% and decrease in cerebral hemispheres by 34%; phenylmethylsulfonyl fluoride-inhibited carboxypeptidase activity increase in hypothalamus by 141%, in striatum by 60% and in optic and lamina quadrigemina by 34%. The role of basic carboxypeptidases in mechanisms of ethanol influence on the peptidergic systems are discussed.  相似文献   
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Data on more than 30 metabolic processes and biochemical reactions, involving corrinoids, which have been described in prokaryotes thus far, are reviewed. These pathways (central or specific, catabolic or anabolic) are inherent in bacteria and archebacteria of diverse phylogenetic lineages, comprising several physiological groups. Particular emphasis is placed on the role of corrinoid-dependent transmethylation in acetogenesis and methanogenesis and on the contribution of adenosylcobalamin in DNA metabolism.  相似文献   
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The effect of vitamin B12 (cobalamin) on DNA biosynthesis in Methylobacterium dichloromethanicum was studied. When cultivated in media with methanol or dichloromethane, the bacterium produced approximately 10 micrograms corrinoids per g dry biomass, compared to about 7 micrograms/g when cultivated on ethanol or succinate. Exogenous adenosylcobalamin (AdoCbl) stimulated DNA biosynthesis in M. dichloromethanicum cells grown under poor aeration, the effect being mediated by AdoCb1-linked ribonucleotide reductase. In vitro studies showed that M. dichloromethanicum also has AdoCbl-independent ribonucleotide reductase. Under good aeration, exogenous AdoCbl had no effect on DNA biosynthesis, while hydroxyurea suppressed it. These data suggest that AdoCbl-independent ribonucleotide reductase, which is likely to be activated by oxygen, plays an important part in DNA biosynthesis when M. dichloromethanicum is cultured with good aeration, whereas AdoCbl-dependent ribonucleotide reductase is active under the conditions of poor aeration.  相似文献   
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The present study was undertaken to determine the diagnostic accuracy of positron emission tomography (PET) in the staging and restaging of malignant lymphomas. For determination of the extent of a neoplastic process, complex radiation examination was conducted in 67 patients with malignant lymphomas. In 12 (17.9%) cases, the stage of the disease was changed, as evidenced by PET. There is evidence that the technique is of high diagnostic accuracy in detecting malignancies of l ymph nodes, skeletal system, and parenchymatous organs in lymphoproliferative diseases.  相似文献   
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Being of global ecological significance, boreal forests of Siberia located at the high latitudes of Northern Eurasia serve as a unique source of genetic, species, and ecosystem diversity. Previously conducted research revealed a wide range of scientific problems regarding the intraspecific diversity of trees, estimation of the structure and current state of forest ecosystems, as well as their ordination and classification. The use of modern information technologies (databases, species diversity indices, GIS) can promote the knowledge on Siberian boreal forests to a higher level.  相似文献   
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The study addresses the effects of higher and lower temperatures experienced during the early stages of ontogeny on the parameters of the subsequent growth and development of the butterfly Inachis io. The caterpillars reared at a temperature of 22°С during instars I–III and then transferred to lower temperatures (16, 18, and 20°C) had higher instantaneous growth rates, larger body mass, and shorter duration of instars IV and V than the caterpillars that developed permanently at these lower temperatures. Vice versa, the caterpillars reared at 16°С during instars I–III and transferred to higher temperatures (18, 20, and 22°C) developed and grew slower than the caterpillars reared at these higher temperatures from the beginning. Possible physiological mechanisms underlying the observed phenomena and their ecological consequences are discussed. Our results are compared with the previously published data on fish—another group of ectothermic organisms, on which similar experiments have been carried out.  相似文献   
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