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排序方式: 共有264条查询结果,搜索用时 15 毫秒
241.
B A Kudriashov Ia M Ammosova L A Liapina N N Osipova L D Azieva G Iu Liapin A V Basanova 《Izvestiia Akademii nauk SSSR. Seriia biologicheskaia》1991,(6):939-943
In the present work, the nature of an anticoagulant from Philipendula ulmaria was studied. A method for purification of this anticoagulant was developed. Using diverse methods it was shown that the molecular weight, data on element (sulphur, nitrogen, and hydrogen) content, spectral characteristics in the infrared region of the spectrum, and electrophoretic properties of the product indicate its similarity to heparin of animal origin. 相似文献
242.
The dynamic studies of the parameters of forced expiration under the conditions of a five-day dry immersion involved seven healthy male subjects aged 20 to 25 years. During forced expiration, spirometry tests were performed simultaneously with tracheal sounds being recorded by a microphone. A number of parameters, including the acoustic duration of the forced-expiration tracheal sounds, the lungs’ forced vital capacity, the 1-s forced expiration volume, the peak expiratory flow, and time of achieving the peak expiratory flow, were recorded before dry immersion, on days 1 and 4 of immersion, and the next day after the termination of immersion. There was a significant decrease (by 8.4%) in the peak expiratory flow on day 1 of immersion; however, by day 4 of immersion, the peak expiratory flow increased by 8.9%, reaching its baseline values. The lungs’ forced vital capacity and the forced expiration volume during 1 second, on the average, did not change throughout the experiment. There was a significant increase (by 17%) in the duration of the forced expiration tracheal sounds after the immersion, which suggests an increase in respiratory resistance and needs further studies. A moderate negative correlation between the duration of the forced expiration tracheal sounds and Gensler’s index (r = ?0.63) was found, whereas the correlation with other spirometry parameters was weak or absent. 相似文献
243.
244.
We have detected and characterized a subpopulation of immunoregulatory cells, i.e., B-helpers capable to enhance the activity of Td-lymphocytes and controlling differentiation of syngeneic hemopoietic stem cells in mouse spleen and bone marrow. B-helpers found in the spleen and lymphatic nodes are resistant to radiation (at a dose of 6 Gr) but are impaired when irradiated at 9 Gr. Manifestation of the helper activity does not require either DNA or RNA synthesis but depends on protein synthesis and is mediated by soluble transmitter substances. Initial activation of B-helpers by lipopolysaccharide or alloantigens does not affect their helper functions. In the absence of T-lymphocytes B-cells do not affect differentiation of hemopoietic stem cells; interaction of B-helpers with differentiating Td-lymphocytes is not genetically restricted. Using preparative electrophoresis, we could isolate fractions of Td-lymphocytes which require or do not require B-helper cells in order to induce change in differentiation of hemopoietic stem cells from mainly erythroid to preferentially granulocyte pathway. 相似文献
245.
N I Osipova T D Cherkasova M Iu Girshovich V P Avrorov V Iu Iurkiv 《Biulleten' eksperimental'no? biologii i meditsiny》1990,109(2):156-158
The changes in the glutathione-dependent and superoxide dismutase (SOD) enzymatic activity in the rat lungs and liver tissues have been studied after the administration of plague murine toxin (LD100). It has been found out the early toxic effect in 1h in the lungs: 35% SOD and glutathione peroxidase (tributyl hydroperoxide) (GP) decrease, 87% glutathione reductase (GR) increase along with two-hold ascent of ratio GR/Glutathione-S-transferase (GT), GR/GPs. The fundamental ratio GR/GT.GPs rises in 1h 3.7 times and then falls below standard rate (5h). This is the evidence of the lungs antioxidant system potential power exhaustion. It has been established that in the liver, 4 times SOD activity increases in 2h after the toxin injection, and 1.5 times GP (tributyL) hydroperoxide) activity ascends in 1h. The ratio increase (150% for SOD/GP-H2O2 in 2h, 114% for GR/GP (tributyl hydroperoxide) and 61% for GR/GT in 5h) indicates the stable unbalance of this system. The pathogenetic significance of detoxication system disturbances in the lungs and liver tissues under the murine toxin influence is discussed. 相似文献
246.
Genetic and demographic characteristics of populations from two settlements from the Aginskii Buryat district of Trans-Baikal krai (Alkhanai and Orlovskii) were studied. It was demonstrated that the mononational Buryat settlement of Alkhanai, located in the agrarian Dul??durginskii region of the district far from large settlements and transport highways, is characterized by a large prereproductive volume (45%) and by a small share of individuals from the elderly age group (16.4%). A shift in age characteristics in the Buryat group (36.6 and 22.4%, respectively) was detected in the urban settlement of Orlovskii with a population of mixed ethnic composition, located in a densely populated industrialized part of the district. A modified sex ratio was also demonstrated in Alkhanai as opposed to the Buryat part of the Orlovskii population (sex indices were 0.94 and 0.99). Analysis of population mixture was conducted; marriage structure and migrations were described. The endogamy index of the Alkhanai locality was 0.41; in the group of Buryats from Orlovskii, 0.09. A decrease in the amount of pregnancies and births and a larger distribution of family planning practice among Buryats from Orlovskii were detected. The average amount of births of living children per woman in Alkhanai was 5.11; in Buryats from Orlovskii, 3.90. The selection pressure was estimated as low by means of the Crow index (I tot 0.28?C0.48). In all described groups, a component that characterizes differential fertility (I f) exceeds the child mortality component (I m). 相似文献
247.
248.
Karpov D. S. Osipova P. G. Domashin A. I. Polyakov N. B. Solovyev A. I. Zubasheva M. V. Zhukhovitsky V. G. Karpov V. L. Poddubko S. V. Novikova N. D. 《Molecular Biology》2020,54(5):757-768
Molecular Biology - At the International Space Station (ISS), artificial living conditions are created and maintained to satisfy human needs, these conditions are also favorable for the growth of... 相似文献
249.
L. I. Kolesnikova M. A. Darenskaya L. A. Grebenkina E. V. Osipova M. I. Dolgikh N. V. Semenova 《Human physiology》2014,40(2):184-189
The pro- and antioxidant statuses of apparently healthy adolescent Tofalar and Evenks of both sexes has been estimated and compared to those of the newcomer Caucasian people. Both girls and boys display an activation of adaptive-compensatory response relative to Caucasian newcomers, which manifests itself as a statistically significant increase in nonenzymatic components of the antioxidant defense system. 相似文献
250.
O B Diundik E V Osipova T A Gil' N P Belezova A L Linitski? 《Nauchnye doklady vysshe? shkoly. Biologicheskie nauki》1988,(1):63-67
The toxicity of industrial waste--the ashes of brown coals in connection with the possibility of their utilization in agriculture has been studied. It has been proved that ash water extracts which give low pH values are practically nontoxic for test objects. Ash extracts rich in calcium and magnesium oxides provide high pH values and has a negative effect on hydrobionts. The neutralization removes the acute toxic effect. 相似文献