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41.
G. K. Stepanova 《Human physiology》2005,31(3):352-357
Morphological and functional criteria permitting the prediction of exercise performance were identified for two ethnic groups of Yakutia (Sakha). Yakuts with a low body height, normotonic autonomic nervous regulation, a relatively high weight-height index, eukinetic blood circulation, and a high specific exercise performance are best adapted to the environment. A high exercise performance in sympathicotonic subgroups cannot be a criterion of good adaptation because it is accompanied by cardiovascular strain even at rest. A high prevalence of sympathicotonia and body weight deficit in the ethnic groups studied reflect maladaptations caused by a set of adverse natural and social environmental factors.__________Translated from Fiziologiya Cheloveka, Vol. 31, No. 3, 2005, pp. 124–130.Original Russian Text Copyright © 2005 by Stepanova. 相似文献
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Anna Stepanova Maria Malunova Svetlana Salamaikina Renat Selimov Aleksandra Solov’eva 《Phyton》2021,90(2):543-552
Rhodiola quadrifida is a rare mountain medicinal plant whose root
extracts are used in traditional Chinese medicine as a hemostatic, antitussive,
and tonic in the treatment of gynecological diseases. The aim of the study was
to obtain R. quadrifida cultures at different degrees of differentiation in vitro
and compare their growth characteristics and the content of salidroside and rosavin. Hairy roots were obtained by incubating cotyledons and hypocotyls in a suspension of Agrobacterium rhizogenes strain A4. The presence of the rolB and
rolC genes was proven by polymerase chain reaction. The obtained roots were
cultivated in Murashige-Skoog medium (MS). Calluses were obtained from the
hairy roots in MS medium with the addition of hormones: 3 mg/L 2,4 D and
0.5 mg/L BAP. The presence of the main secondary metabolites of R. quadrifida,
salidroside and rosavin, in calluses and salidroside in hairy roots by HPLC/MS
was confirmed. The content of salidroside in callus culture was significantly
higher than in hairy roots, 0.158 and 0.047%, respectively. The content of rosavin
in callus culture was 0.07%. The content of rosavin and salidroside in callus culture
was close to the level of these substances in the rhizomes of R. quadrifida plants
growing in vivo, making this culture promising for its possible biotechnological use. 相似文献
44.
小麦族(Triticeae)是禾本科、早熟禾亚科中一个有重要经济价值、以多年生植物占优势的族,族内绝大多数种类是重要的粮食作物和畜牧业上的优良牧草,饲用价值极高,有些种类具有耐寒、耐旱、耐碱等特性,是农牧业上良种繁育、牧草利用的重要基因资源。但该族同时又是分类学上的一个疑难族,各学者对族内系统分类意见不一、争议颇大,尤其在族的界限、族下类群划分以及类群演化关系上问题较多,至今尚未解决。查阅了国内外分类学文献,探讨其分类差异以及存在问题,为充分开发利用中国丰富的小麦族植物资源提供理论依据。 相似文献
45.
LISE COMTE LAËTITIA BUISSON MARTIN DAUFRESNE GAËL GRENOUILLET 《Freshwater Biology》2013,58(4):625-639
1. Climate change could be one of the main threats faced by aquatic ecosystems and freshwater biodiversity. Improved understanding, monitoring and forecasting of its effects are thus crucial for researchers, policy makers and biodiversity managers. 2. Here, we provide a review and some meta‐analyses of the literature reporting both observed and predicted climate‐induced effects on the distribution of freshwater fish. After reviewing three decades of research, we summarise how methods in assessing the effects of climate change have evolved, and whether current knowledge is geographically or taxonomically biased. We conducted multispecies qualitative and quantitative analyses to find out whether the observed responses of freshwater fish to recent changes in climate are consistent with those predicted under future climate scenarios. 3. We highlight the fact that, in recent years, freshwater fish distributions have already been affected by contemporary climate change in ways consistent with anticipated responses under future climate change scenarios: the range of most cold‐water species could be reduced or shift to higher altitude or latitude, whereas that of cool‐ and warm‐water species could expand or contract. 4. Most evidence about the effects of climate change is underpinned by the large number of studies devoted to cold‐water fish species (mainly salmonids). Our knowledge is still incomplete, however, particularly due to taxonomic and geographic biases. 5. Observed and expected responses are well correlated among families, suggesting that model predictions are supported by empirical evidence. The observed effects are of greater magnitude and show higher variability than the predicted effects, however, indicating that other drivers of changes may be interacting with climate and seriously affecting freshwater fish. 6. Finally, we suggest avenues of research required to address current gaps in what we know about the climate‐induced effects on freshwater fish distribution, including (i) the need for more long‐term data analyses, (ii) the assessment of climate‐induced effects at higher levels of organisation (e.g. assemblages), (iii) methodological improvements (e.g. accounting for uncertainty among projections and species’ dispersal abilities, combining both distributional and empirical approaches and including multiple non‐climatic stressors) and (iv) systematic confrontation of observed versus predicted effects across multi‐species assemblages and at several levels of biological organisation (i.e. populations and assemblages). 相似文献
46.
E.?I.?KulaginaEmail author Ya.?A.?Vevel T.?I.?Stepanova E.?L.?Zaytseva 《Paleontological Journal》2016,50(6):557-572
The genus Tournayellina (family Chernyshinellidae), important for stratigraphy of the Devonian–Carboniferous boundary interval, is revised. Species and generic morphological characters are considered and the species composition of the genus is revised. The evolution of the family is discussed and its geographical and stratigraphic distribution is examined. The species Tournayellina quadrilobata Postojalko, 1999 is redescribed in accordance with new data on its morphology. The new species T. intermedia Stepanova, sp. nov. is established. 相似文献
47.
A study of Russian cystic fibrosis (CF) patient DNA was conducted to assess the incidence frequency of 19 mutations, namely CFTRdele2,3(21kb), F508del, I507del, 1677delTA, 2143delT, 2184insA, 394delTT, 3821delT, L138ins, 604insA, 3944delGT, G542X, W1282X, N1303K, R334W, and 3849 + 10kbC > T, S1196X, 621 + 1g > t, and E92K of the CFTR gene. We also sought to determine the estimated CF frequency in Russian Federation. In addition, we determined the total information content of the approach for 19 common mutations registration in the CFTR gene, 84.6%, and the allelic frequencies of the examined mutations: three mutations were observed with a frequency exceeding 5% (F508del, 53.98%, E92K, 6.47%, CFTRdele2,3(21kb), 5.35%); other mutations were observed with frequencies ranging from 0.13 to 3.0%. The CF population carrier frequency was 1 in 38 subjects, while the predicted CF frequency was 1 in 5776 newborns. 相似文献
48.
本研究旨在探讨谷糠结合态多酚(bound phenol of inner shell,BPIS)发挥抗乳腺癌细胞活性的作用机制。首先采用细胞计数法检测BPIS对乳腺癌细胞以及正常乳腺细胞活性的影响;然后综合运用SEA、SIB以及GeneCards等数据库获得BPIS和乳腺癌的相关靶点,并分析活性成分与作用靶点的互作网络以及通路。本研究筛选得到BPIS抗乳腺癌相关靶点39个,主要涉及糖脂代谢和细胞自噬等生物过程以及MAPK、PI3K/AKT、FoxO等多条信号通,表明BPIS抗乳腺癌是多成分、多靶点、多通路协同作用的过程,而与细胞死亡相关的细胞自噬很可能在BPIS抑制乳腺癌过程中发挥主要作用。 相似文献
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50.
N F Babushkina Z L Stepanova T E Snitkovskaia R Migranova 《Ukrainski? biokhimicheski? zhurnal》1992,64(2):114-118
Energy metabolism and microsomal oxidation in the liver of meadow mice caught near a source of technogenic pollution (0.5 km from the enterprise) were studied for 2 years for their peculiarities. Intensification of oxidative processes of succinic acid in the liver mitochondria and a tendency to a decrease of glycolysis in the liver homogenates were observed. Under conditions of technogenic pollution in liver of animals the level of lipid peroxidation and rate of aniline metabolism increase. Activation of the processes of aminopyrine metabolism took place in the meadow mice liver only for one season. The next year the rate of aminopyrine metabolism in the animals liver was lower. This is explained by the system inhibition under the effect of technogenic factors. Therefore, the investigation of biochemical indices is used to indicate the unfavourable effect of technogenic factors in the natural populations of small rodents. 相似文献