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The antigenic variant of simian adenovirus 7 (SA7) DNA was cleaved by restriction endonucleases EcoRI, XbaI, BamHI, SalI. The resulted digests of viral DNA were tested for transforming activity using the "calcium" technique. It was shown that BamHI. XbaI and SalI digests transformed primary baby rat kidney cells as well as native viral DNA. The transforming activity of separated BamHI and SalI fragments was tested also. The viral DNA fragments with transforming activity (BamHI-B and SalI-B) were localised on the left of the physical map of the viral genome. It was also shown that fragment-transformed cell lines were able to form colonies in 0.33% agarose medium.  相似文献   
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Intermembrane transfer and exchange of tocopherol are not well understood. To study this we tested the ability of alpha-tocopherol containing unilamellar donor liposomes to inhibit the accumulation of lipid peroxidation products in acceptor liposomes. With molar ratios of alpha-tocopherol:phospholipids from 1:100 to 1:1000 in donor liposomes prepared by sonication of lipid dispersions, alpha-tocopherol was incorporated into both monolayers and was homogenously distributed in monomeric form without forming clusters in the liposomes. Concentrations of alpha-tocopherol which completely prevented the peroxidation of lipids were chosen for donor liposomes. Hence inhibition of lipid peroxidation in mixtures of donor and acceptor liposomes was determined by the antioxidant effect of alpha-tocopherol in acceptor liposomes which resulted from intermembrane transfer and exchange of alpha-tocopherol. Evidence was obtained that this was not due to fusion of donor with acceptor liposomes. The efficiency of the "intermembrane" antioxidant action of tocopherol was more pronounced when donor liposomes contained unsaturated phospholipids, indicating that the presence of unsaturated fatty acids in the outer monolayer phospholipids facilitates intermembrane tocopherol exchange.  相似文献   
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The authors assess mobile methods of x-ray computer-aided tomography (CAT) and suggest an organization and methodological scheme of its application. Their program of the first and up to now the only one in this country mobile CAT device is based on the new principles of mobile CAT application. It is realized in special hospitals of large regions, where the patients with the optimal indications for CAT are assembled. Over 15,000 examinations were carried out with the use of the suggested CAT program over 4 years, that resulted in detection of 1295 brain tumors, 804 cases with neoplastic involvement of the abdominal cavity and the retroperitoneal space. The authors claim that wide application of mobile CAT devices according to the program they suggest will help decide the problem of unavailability of such examinations, for it will rule out the principal cause of this unavailability--economic problems arising because of high price of this equipment. One mobile device may replace 3 permanent CAT devices, if used according to the program suggested by the authors.  相似文献   
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The genetic composition of the Russian population was investigated by analyzing both mitochondrial DNA (mtDNA) and Y-chromosome loci polymorphisms that allow for the different components of a population gene pool to be studied, depending on the mode of DNA marker inheritance. mtDNA sequence variation was examined by using hypervariable segment I (HVSI) sequencing and restriction analysis of the haplogroup-specific sites in 325 individuals representing 5 Russian populations from the European part of Russia. The Y-chromosome variation was investigated in 338 individuals from 8 Russian populations (including 5 populations analyzed for mtDNA variation) using 12 binary markers. For both uniparental systems most of the observed haplogroups fell into major West Eurasian haplogroups (97.9% and 99.7% for mtDNA and Y-chromosome haplogroups, respectively). Multidimensional scaling analysis based on pairwise F(ST) values between mtDNA HVSI sequences in Russians compared to other European populations revealed a considerable heterogeneity of Russian populations; populations from the southern and western parts of Russia are separated from eastern and northern populations. Meanwhile, the multidimensional scaling analysis based on Y-chromosome haplogroup F(ST) values demonstrates that the Russian gene pool is close to central-eastern European populations, with a much higher similarity to the Baltic and Finno-Ugric male pools from northern European Russia. This discrepancy in the depth of penetration of mtDNA and Y-chromosome lineages characteristic for the most southwestern Russian populations into the east and north of eastern Europe appears to indicate that Russian colonization of the northeastern territories might have been accomplished mainly by males rather than by females.  相似文献   
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The authors analyze the current views of incidentally discovered adrenal masses and the potentialities of ultrasound study (US), computed tomography (CT), and magnetic resonance imaging (MRI) in their detection and presents the US, CT, and MRI symptoms of different incidentally discovered adrenal masses. Due to the availability and almost extensive application of US apparatuses, they define the importance of US screening of the adrenal region and emphasize the capacities of echographic differentiation of cystic and solid adrenal masses in patients with different diseases of the abdomen and retroperitoneal space. The authors also note the basic role of CT and MRI in the specified topical diagnosis of retroperitoneal space lesions and in the presumption of the morphological structure of some tumor and tumoroid (hyperplasia-type) adrenal changes.  相似文献   
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Aqueous extracts from fruit bodies and mycelia of various higher Basidiomycetes were studied in search for reliable biological effects. In vitro and in vivo experiments were conducted. The results showed that the aqueous extracts demonstrated various types of marked biological actions: an increased production of reactive oxygen forms by neutrophil cells of human peripheral blood; a significant mitogenic activity in a wide range of concentrations; stimulation on production of inflammatory cytokines interleukine 1-beta and interleukine-8 by peripheral blood cells; a decrease in both average tumor size in mice with transplanted melanoma B16 and a manifestation of tumorous intoxication; and a prolongation in the survival rate of such mice.  相似文献   
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