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Summary Genetically identical copies of the silkworm female obtained via ameiotic parthenogenesis are insignificantly depressed by artificial reproduction, and notwithstanding their isogenous pattern, they show the same variability in quantitative characters as in the heterogenous forms.By means of androgenesis, genetically identical copies of strictly homozygous males were obtained; the latter were produced via meiotic parthenogenesis. The androgenetic clones of these males were transformed by backcrosses into homozygous bisexual lines. Viability and cocoon weight in these lines were higher than those in androgenetic clones of similar genotype, but they were far from the norm due to the depressing effect of semilethals left in them in a homozygous state. An extremely low phenotypical variability of quantitative characters is observed in the isogenous hybrids F1 obtained from crossing two genetically dissimilar strictly homozygous individuals. These hybrids make excellent material for phenogenetical studies. The female and male isogenous clones have an increased combining ability which is acquired in the course of their selection for high disposition towards complete parthenogenesis. For practical purposes it is proposed to take a female and a male which when mated produce a high-quality family and clone them separately, the first via parthenogenesis, the latter via androgenesis. After mating these reproduced bisexual clones, it will be possible to obtain in successive generations a vast number of families repeating the prominent productivity of the initial family.  相似文献   
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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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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   
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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   
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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   
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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   
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