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71.
Zh. A. Antipushina 《Biology Bulletin》2010,37(9):886-894
The invertebrate remains from occupation layers of three ancient Aleutian settlements on Adak Island (Aleutian Islands) were
studied to reconstruct the dynamics of the zoogeographic structure of invertebrate species in the Middle and Late Holocene.
The radiocarbon age of the oldest deposit is about 7000 BP. The modern littoral macrozoobenthos of the Bering and Mednyi islands
(Commander Islands) and Adak Island (Aleutian Islands) was studied. It was found that the overall zoogeographic structure
of the macrozoobenthos in the studied regions has not changed significantly over the last 7000 years; however, the ratio of
species and their populations varied depending on the dynamics of climate conditions. 相似文献
72.
Ivankova ZhE Irzhak LI Pravdukhina NA Alisultanova NZh Sivkova VV 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2010,96(10):1030-1033
Arterial and venous blood samples from babies' umbilical cord vessels before lung breath beginning were used to measure arterial-venous difference between lactate dehydrogenase activity, pH and oxygen blood saturation (sO2). Enzyme activity was 735.4 +/- 90.8 U/L in venous blood and 672.0 +/- 108.1 U/L in arterial one, pH 7.21 +/- 0.06 and 7.32 +/- 0.06, sO2 32.9 +/- 12.7 and 56.5 +/- 18.3%, respectively. Reverse correlation between enzyme activity, pH and sO2 was found. 相似文献
73.
淡紫拟青霉胞外多糖的分离、纯化及结构分析 总被引:4,自引:0,他引:4
淡紫拟青霉NH-PL-03菌株的胞外多糖粗提物对枯萎病病原菌-尖孢镰刀菌具有较好的抑制效果,文中对淡紫拟青霉胞外多糖进行了分离纯化和结构分析,以期为其构效关系研究奠定基础。采用乙醇沉淀法从淡紫拟青霉发酵液中提取粗多糖,经Sevage法脱蛋白后,过Superdex-G75凝胶层析柱分离得到胞外多糖EP-1。紫外分光法和Sephacryl S-200 HR凝胶层析柱检测EP-1为均一多糖,Sephacryl S-200柱层析测得EP-1的分子量为35.2 kDa,完全酸水解后纸层析检测EP-1的单糖组成中仅有葡萄糖,红外光谱、高碘酸氧化和Smith降解结果表明EP-1的化学结构是以β-(1,3)糖苷键连接而成的无分枝的葡聚糖。刚果红络合试验表明EP-1在稀的碱溶液中以3股螺旋构象存在。 相似文献
74.
75.
It is shown that over 80% of nuclear neutral lipids are found in the nuclear membrane preparations, whereas only 7%--in chromatin. The injection of hydrocortisone to animals significantly decreases the neutral lipids content in both fractions. These results and the data obtained previously by the authors indicate the possible participation of nuclear membrane and chromatin lipids in the process of hormonal regulation of the genetic activity. 相似文献
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79.
Zh. V. Nagornova 《Human physiology》2007,33(3):277-284
The EEG was recorded in 19 standard derivations according to the international 10–20 system in 30 subjects during a test for figurative creativity. To involve subjects in the creative process, they were presented with the following creative tasks: (Cr1) thinking up and drawing an original picture; (Cr2) drawing a face, a house, and a clown in an original manner; (C1) drawing a picture from memory; and (C2) drawing geometric figures without any system. All the tasks had to be performed using a given set of geometric figures (a circle, semicircle, triangle, and rectangle). Statistical analysis of the EEG spectral power for the frequency bands α1, α2, β1, β2, and γ showed that the creative task performance was characterized by an increase in the EEG power in the β2 and γ bands and single differently directed power changes in the α1, α2, and β1 bands. The findings were compared to previous results of EEG studies on creative activity. 相似文献
80.
Kraeva LA Manina ZhN Tseneva GIa Radchenko AG 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2007,(5):3-7
Bacteriologic examination of 1589 patients showed that, aside from C. diphtheriae, 11% of acute upper respiratory tract infections were caused by other Corynebacterium species. Such bacteria can cause infections of various localizations (bronchitis, pyelonephritis, urethritis, colpitis, dermatitis, arthritis, etc.). C. pseudodiphtheriticum and C. xerosis were isolated from clinical specimens most frequently. Corynebacterium spp. have adhesive, hemolytic, hemagglutinating, and neuraminidase activity; some of them are highly pathogenic. The most virulent, were following species: C. diphtheriae, C. pseudotuberculosis, C. urealyticum, and C. ulcerans. Corynebacterium non diphtheriae were frequently isolated from clinical specimens in association with staphylococci and streptococci. In such cases, factors of pathogenicity and resistance to antibiotics were more pronounced. Strains isolated with association with other bacteria have lost susceptibility to tetracycline, oleandomycin, penicillin, and erythromycin. It is important to be vigilant about bacteria from Corynebacterium genus in clinical settings, and thoroughly study their biologic characteristics, especially in immunocompromised patients. 相似文献