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391.
B. V. Davydov G. P. Stepanova Z. A. Krivitsina A. L. Vorontsov Yu. I. Voronkov 《Human physiology》2017,43(7):826-828
Our studies have shown that physical activity (bicycle ergometry) alters the biochemical status of male volunteers. We observed a significant decrease of glucose level and an increase in concentration of magnesium, phosphorus and especially of lactic acid in capillary blood after 5 min of bicycle ergometry start. Creatine phosphokinase activity and the concentration of triglycerides did not differ significantly from the original values. The tendency of changes in the examined parameters was the same in the supine and in the sitting positions. Therefore, biochemical investigations may complement essentially the physiological and neurophysiological tests of human adaptability to physical loads. The method of dry chemistry described in this study can be effectively used in a space flight as the rapid method for evaluation of biochemical parameters of the body. 相似文献
392.
Godina EZ Khomyakova IA Purundjan AL Zadorozhnaya LV Stepanova AV 《Journal of PHYSIOLOGICAL ANTHROPOLOGY and Applied Human Science》2005,24(4):313-319
2,106 girls and 2,169 boys from 7 to 17 were investigated in 2002-2004 in three urban settlements of the Saratov region (Povolzhje area): the town of Khvalynsk, population 15,000, with a low level of industrialization; the city of Balakovo, population 220,000, highly industrialized and with a nuclear power station; and the city of Saratov, population around 1,000,000 a regional capital, and also highly industrialized. The whole area, particularly the location of Khvalynsk, is also characterized by iodine deficiency (iodine concentration is 0.78 mkg/kg v. normal values of 5-7 mkg/kg).The program included about 30 anthropometric measurements, evaluation of developmental stages of secondary sexual characteristics, and information on menarcheal age by the status quo method. Information on parental occupation and education, as well as number of children per family was collected by questionnaire. For the analysis all the data were standardized, and further comparisons were made irrespective of age groups. The significance of differences was assessed by one-way ANOVA. For height, weight and chest circumference there are significant differences among the three populations (p < 0.001), with Khvalynsk children being the smallest in body height and weight. However, in chest circumference they are close to or even bigger (girls) than Balakovo children. The children from Khvalynsk are characterized by the lowest values for subcutaneous fat layer, both on the trunk and extremities. For the age of menarche, Khvalynsk girls have the highest values: 13 years 5 months (13.42). In Balakovo and Saratov, the corresponding figures are identical: 13 years 2 months (13.17). Secular changes in Khvalynsk and Saratov children are discussed as compared to the literature. 相似文献
393.
394.
Sultanov ZZ Stepanova ED Kulakova LS Omarova SM Gorelova VG Ramazanova NR Gadzhieva SM 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2005,(3):19-22
The effectiveness of the bacteriological study of the blood depends in many aspects on the quality of nutrient media. The currently approved nutrient media for the isolation and yield of hemocultures have low isolation rates and require prolonged time for the isolation of causative agents. A two-phase nutrient medium for the yield and isolation of hemoculture has been developed. This medium has been found to have advantages over the control "double medium" in sensitivity, yield effect, growth rate and isolation rate with respect to the causative agents of bacteriemia and sepsis. The medium is standard and ready for use. The above-mentioned advantages of the medium increase the quality of the bacteriological diagnosis of bacteriemia and sepsis. 相似文献
395.
396.
Altered distribution of plasma PAF-AH between HDLs and other lipoproteins in hyperlipidemia and diabetes mellitus 总被引:2,自引:0,他引:2
Kujiraoka T Iwasaki T Ishihara M Ito M Nagano M Kawaguchi A Takahashi S Ishi J Tsuji M Egashira T Stepanova IP Miller NE Hattori H 《Journal of lipid research》2003,44(10):2006-2014
Platelet-activating factor acetylhydrolase (PAF-AH) is a phospholipase A2 associated with lipoproteins that hydrolyzes platelet-activating factor (PAF) and oxidized phospholipids. We have developed an ELISA for PAF-AH that is more sensitive than previous methods, and have quantified HDL-associated and non-HDL-associated PAF-AH in healthy, hyperlipidemic, and diabetic subjects. In healthy subjects, plasma total PAF-AH concentration was positively correlated with PAF-AH activity and with plasma total cholesterol, triacylglycerol, LDL cholesterol and apolipoprotein B (apoB) concentrations (all P < 0.01). HDL-associated PAF-AH concentration was correlated positively with plasma apoA-I and HDL cholesterol. Subjects with hyperlipidemia (n = 73) and diabetes mellitus (n = 87) had higher HDL-associated PAF-AH concentrations than did controls (P < 0.01). Non-HDL-associated PAF-AH concentration was lower in diabetic subjects than in controls (P < 0.01). Both hyperlipidemic and diabetic subjects had lower ratios of PAF-AH to apoB (P < 0.01) and higher ratios of PAF-AH to apoA-I (P < 0.01) than did controls. Our results show that the distribution of PAF-AH mass between HDLs and LDLs is determined partly by the concentrations of the lipoproteins and partly by the mass of enzyme per lipoprotein particle, which is disturbed in hyperlipidemia and diabetes mellitus. 相似文献
397.
Stepanova IIu Eprintsev AT Falaleeva MI Parfenova NV Grabovich MIu Patritskaia VIu Dubinina GA 《Mikrobiologiia》2002,71(4):445-451
Major pathways of carbon metabolism were studied in strains D-402 and D-405 of freshwater colorless sulfur bacteria of the genus Beggiatoa grown organotrophically and mixotrophically. The bacteria were found to possess all the enzymes of the tricarboxylic acid (TCA) and glyoxylate cycles. When organotrophic growth changed to mixotrophic one, the activity of the TCA cycle enzymes decreased 2- to 3-fold, but the activity of enzymes of the glyoxylate cycle increased threefold. It follows that, in the oxidation of thiosulfate, organic compounds no longer play the leading part in the energy metabolism, and most of electrons that enter the electron transport chain (ETC) derive from inorganic sulfur compounds. A connection was established between the structure and kinetic characteristics of malate dehydrogenase--an enzyme of the TCA and glyoxylate cycles--and the type of carbon metabolism in the strains studied. Malate dehydrogenase in organotrophically grown cells of strains D-402 and D-405 is dimeric, whereas in strain D-402 grown mixotrophically it is tetrameric. 相似文献
398.
The urokinase type plasminogen activator (urokinase) plays a pivotal role in the regulation of cell adhesion and migration during tissue remodeling. Urokinase not only specifically cleaves plasminogen and converts it into plasmin but also activates intracellular signaling upon binding to certain receptors on the cell surface. The polyfunctional properties of this protein are associated with its three-domain structure as follows: the C-terminal proteolytic domain containing the serine protease active center, the central kringle domain, and the N-terminal domain homologous to epidermal growth factor. This review considers functional properties of urokinase and of its fragments generated on the cell surface as a result of proteolytic processing. This review will discuss the mechanisms of urokinase-mediated regulation of cellular function upon binding to membrane receptors. 相似文献
399.
Weinberg HS Korol AB Kirzhner VM Avivi A Fahima T Nevo E Shapiro S Rennert G Piatak O Stepanova EI Skvarskaja E 《Proceedings. Biological sciences / The Royal Society》2001,268(1471):1001-1005
Exposure to ionizing radiation has long been suspected to increase mutation load in humans. Nevertheless, such events as atomic bombing seem not to have yielded significant genetic defects. The Chernobyl accident created a different, long-term exposure to radiation. Clean-up teams (or 'liquidators') of the Chernobyl reactor are among those who received the highest doses, presumably in some combination of acute and chronic forms. In this study, children born to liquidator families (currently either in the Ukraine or Israel) conceived after (CA) parental exposure to radiation were screened for the appearance of new fragments using multi-site DNA fingerprinting. Their sibs conceived before (CB) exposure served as critical internal controls, in addition to external controls (non-exposed families). An unexpectedly high (sevenfold) increase in the number of new bands in CA individuals compared with the level seen in controls was recorded. A strong tendency for the number of new bands to decrease with elapsed time between exposure and offspring conception was established for the Ukrainian families. These results indicate that low doses of radiation can induce multiple changes in human germline DNA. 相似文献
400.
Giunter EA Stepanova EB Sveranovskaia VV Gervazieva VB 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2001,(5):58-61
Increased sensitivity to benzylpenicillin, ampicillin, claforan, cefzol, novocain and lidocaine was determined by means of the leukocyte allergic alteration (LAA) test in 599 patients with intolerance reactions to these preparations in their medical history. In most of these patients the test results exceeded 30% and reached 98%, their average values exceeding those in the control group no subjects with no drug intolerance. The LAA test ensured a high level (83%) of the detection of drug intolerance. 相似文献