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1.
The main aim of this paper, by the authors' intention, was to attempt to study and provide evidence for that routine transabdominal sonography has great capacities in diagnosing small intestinal strangulation and obstruction ileus caused by commissures or tumors. The data of 48 cases of small intestinal ileus (27 of its strangulation form and 21 of its obturation one) were analyzed. The paper details guidelines on ultrasonographic techniques and the ultrasound semiotics of this pathology. It is the first time that the authors give individual methodological and semiotic approaches at sonography in this group of papers. They present a particularly clinical picture in combination with ultrasonographic data by providing their constant comparison, which serves as an additional support of the results of this paper. In the authors' opinion, the findings suggest that transabdominal sonography may be a successful basic diagnostic technique for strangulation and obturation forms of small intestinal ileus.  相似文献   
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Menadione and vicasol completely restore the respiration rate of rat liver mitochondria after its inhibition by rotenone. Under the same conditions these compounds stimulate oxygen consumption by rabbit heart mitochondria up to 40% of the maximal uncoupled respiration rate in the presence of 5 mM glutamate and up to 30% of the maximal uncoupled respiration rate in a lymphocyte suspension containing glucose. Cyanide and dicumarol, specific inhibitors of DT-diaforase, completely suppress the stimulating effect of menadione and vicasol in isolated mitochondria and by 50% in lymphocyte suspensions. The DiS-C3-(5) fluorescence in lymphocyte suspensions suggests that the menadione and vicasol-induced respiration is capable of supporting the mitochondrial transmembrane potential in lymphocytes. Thus, in different tissues menadione and vicasol can restore oxygen consumption in mitochondria, in which the first and second energy coupling sites are inhibited.  相似文献   
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In search of the basis of distinguishing amenorrhea, due to chromosomal mosaicism and other causes, 179 females affected by primary or secondary amenorrhea were examined, 83 of them being 45,X/46,XX mosaics. 119 traits characterizing the morphological status of the musculoskeletal and reproductive systems, as well as skin, hair and nails were scored. By means of statistical approaches, a group of 21 traits were specified, which makes it possible to diagnose the amenorrhea of chromosomal origin. Statistically significant association between the clinical manifestations and the rate of mosaicism was shown.  相似文献   
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The comparative electron-microscopic study of early stages of the interaction of Y. pseudotuberculosis virulent strain (No. 282) with "professional" (macrophages) and "nonprofessional" (HeLa cells) phagocytes has been carried out. The character of the intimate mechanism of this interaction has been found to be essentially different. The common feature for both systems is the adsorption of bacteria and their penetration into cells due to phagocytosis. But the subsequent fate of Y. pseudotuberculosis is different. In HeLa cells they are isolated from the cytoplasm by multilayer membrane structures, thus remaining morphologically intact. In macrophages the destruction of the microbe in phagolysosomes occurs.  相似文献   
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Two biologically active compounds, the enzyme superoxide dismutase (EC 1.15.1.1) and the antiarrhythmic indole alkaloid ajmaline, were isolated from a callus culture of Rauwolfia serpentina Benth. Sequential isolation of biologically active compounds by metal-chelate affinity chromatography followed by azoadsorbent affinity chromatography allowed us to obtain highly purified products. The yields of superoxide dismutase and ajmaline were 180 mg/kg biomass and 16.5 g/kg dry weight, respectively.  相似文献   
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The cytological expression of spontaneous mutation sy2 isolated from a population of weedy rye was examined. It was demonstrated that the primary defect of meiosis in the mutant plants is nonhomologous synapsis, which occurs simultaneously with the homologous one. An electron microscope study of the synaptonemal complex (SC) at prophase I showed synaptic abnormalities that manifested as "switches" of synapting axial elements to the nonhomologous partner and the formation of foldbacks of lateral SC elements. The sy2 mutants are characterized by one to two such events per meiosis. Nonhomologous synapsis leads to the appearance of univalents at metaphase I (on average 4.16 +/- 0.022 per meiocyte) and multivalents (on average 0.12 +/- 0.007 per meiocyte). The presence of multivalents in 12.0% of meiocytes at metaphase I may result from recombination in ectopic regions of homology. It is suggested that the sy2 mutation impairs a component of the system that limits synapsis in meiocytes to only homologous chromosome pairs.  相似文献   
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This paper considers the major patterns of downstream migration in Arctic lamprey ammocoetes in Kamchatka rivers. Ammocoetes of different age groups are shown to be constantly noted in the composition of the migrant part of a river community. The greatest intensity of downstream migration in ammocoetes of the age class 0+ is noted in the period of their primary dispersion in late July-early August. The ammocoetes of the age groups 1+ and older migrate from spring to late autumn, but their concentrations are not high. The significant similarity of such a biologic feature as downstream migration in ammocoetes and juvenile salmonids serves as an example of ecological analogy.  相似文献   
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