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Ethanol elimination from the blood of rats with different psychophysiological features was studied using gas chromatographic head-space analysis in the general complex of tests aimed at determination of ethanol consumption. The selection of animals with different levels of the initial alcohol motivation was performed according to modified Porsolt's method. It was shown that the initial level of predisposition to depression-like states is in a dose-dependent correlation with the high rate of ethanol elimination. This is suggested to be one of the genetic indications which promotes the formation of the initial alcohol motivation and the development of experimental alcoholism.  相似文献   
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The methods for determining the level of type A Perfringens antitoxin in human blood sera were examined and compared. The ratios for correlating the data obtained in the toxin neutralization test (NT) in vivo, in the passive hemagglutination test (PHT), and as a result of the enzyme-labeled immunosorbent assay (ELISA) with regard to the antitoxin level measured in the NT in vitro were equal to 0.88, 0.64 and 0.39, respectively. The sensitivity of the NT in vivo and in vitro was 0.25 IU/ml, that of the PHT 0.01-0.005 IU/ml, and that of the ELISA 0.01-0.02 IU/ml Perfringens antitoxin. To perform the NT, not less than 1 ml blood serum is required, while for the PHT and ELISA, 0.1-0.05 ml. Provided hyghly purified anatoxin is used for preparing the erythrocyte diagnosticum Perfringens, and polysterene plates are sensitized in performing the ELISA, all the reactions are specific. While titrating human blood sera containing type A Perfringens antitoxin, use in the PHT may be made of type A Perfringens rabbit antiserum as reference.  相似文献   
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Heptapeptide Met-Glu-His-Phe-Pro-Gly-Pro (ACTH4-10 analog) at a dose of 0.015 mg/kg failed to alter open field behaviour of rats in the first test series. The peptide abolished amphetamine-induced stimulation of the exploratory and grooming behaviour. Extinction of the rats' exploratory behaviour during second test series in the open field (7 days later) was disturbed when haloperidol or apomorphine were injected before the first test series. When the peptide was administered with haloperidol or apomorphine, the extinction tended to become normal. Heptapeptide failed to change noradrenaline, dopamine or 5-hydroxytryptamine content in the rat forebrain. However, this peptide at a concentration of 10(-4) M moderately diminished tyrosine hydroxylation velocity in the rat striatal or hypothalamic synaptosomes, the effect depending on tyrosine concentration. These data suggest the involvement of catecholaminergic component into the heptapeptide action on the behaviour of rats.  相似文献   
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The results of prolonged dynamic observations on the state of herd immunity against poliomyelitis virus in an industrial city are given. The survey covered 1304 children. The data thus obtained, when synchronized according to years, seasons, the age of the surveyed children and the methods used in the survey, indicated that in every age group 20-30% of children had no antibodies to group I poliomyelitis virus and 30% of children had no antibodies to group III poliomyelitis virus. The geometrical mean of antibody titers to different types of the virus fluctuated from 1.8 to 4.6 log2, the lowest value being obtained for the titer of antibodies to type III poliomyelitis virus. During the whole period of immunological control (1974-1978) no mass circulation of poliomyelitis virus and no outbreaks of poliomyelitis were registered despite the fact that a considerable proportion of children having no antibodies to one or several types of the virus was constantly present among the most susceptible part of children.  相似文献   
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The presence of neutral alpha-mannosidase activity in normal and pathological lymphoid cells has been demonstrated. The specific activities of the enzyme in different cell types were similar with the exception of B-cells from B-CLL patients when it was a little higher. The activity of acid alpha-mannosidase was also determined in these lymphoid cells. The neutral to acid alpha-mannosidase activity ratio was different in B- and T-cells: in the former neutral alpha-mannosidase activity prevailed, whereas in the latter the predominance of acid alpha-mannosidase activity was apparent. Neutral alpha-mannosidases from pathological B- and T-cells were partially purified and their properties were investigated. In both cell types the enzyme was localized in the cytosol, was very labile and could be stabilized with Mn2+ and dithiothreitol. The enzyme was activated by Co2+ and inhibited by Zn2+ and EDTA. Swainsonine inhibited the B-cell neutral alpha-mannosidase somewhat more strongly in comparison with the T-cell enzyme.  相似文献   
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长江经济带林地和其他生物质碳储量及碳汇量研究   总被引:1,自引:0,他引:1  
以全国林业应对气候变化碳汇计量监测体系建设结果数据为基础,应用森林碳库专项调查建立的碳计量模型和参数,结合历次森林资源清查成果等数据,估算了2020年长江经济带林地和其他生物质碳储量和碳汇量。研究表明:(1)2020年长江经济带林地碳储量24543.58 Tg C (其中森林植被碳储量为4372.85Tg C),散生木和四旁树等其他生物质碳储量329.59 Tg C。2020年长江经济带林地碳汇量81.81 Tg C/a (300.26Tg CO2/a)、散生木和四旁树等其他生物质碳汇量6.60 Tg C/a (24.21 Tg CO2/a)。无论是林地和其他生物质碳储量、碳汇量、还是森林植被碳储量,乔木林地所占比例最大(69%-85%);长江经济带11个省市中,云南省最大,上海市最小;林地碳储量中土壤有机质碳库贡献最大(81.46%),林地碳汇量中生物量碳库贡献最大(90.99%);林地碳汇量中"一直为林地的土地"产生碳汇量贡献最大(71.74%),其中一直为乔木林的土地产生的碳汇量占69.89%;(2)阐述了长江防护林工程、天然林资源保护工程、珠江防护林工程和沿海防护林工程4大重点生态工程对长江经济带碳储量和碳汇量的贡献,长江防护林工程贡献率最大(81%-83%),其次是天然林资源保护工程(32%-38%),珠江防护林工程和沿海防护林工程影响较小。分析了人工造林、中幼林抚育、次生林和低效林改造、退化林修复等生态保护修复措施对长江经济带碳储量和碳汇量的贡献,并提出了碳中和愿景下森林固碳增汇的有效途径。  相似文献   
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