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1.
Summary A new fructose based medium was developed to growBeauveria nivea ATCC 34921 for the production of Cyclosporin A (CyA). Two different sugars and three different nitrogen sources were used for CyA production. Different pH levels in the broth revealed that the best pH for CyA production was 5.5. Maximum concentration of 170 mg CyA/L of broth was obtained with the new medium in 8 days corresponding to yields of 14.8 mg CyA/g dry weight biomass and 5.67 mg CyA/g fructose supplied.  相似文献   
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Phenotype and gene frequency data are presented on the glyoxalase I (GLO) polymorphism in seven endogamous caste groups: Jat Sikh, Ramdasia Sikh, Ramgarhia Sikh, Khatri, Brahmin and Bania of Patiala district, and Jat Sikh of Faridkot district of Punjab, North-West India. Apparently, there is considerable heterogeneity in the frequency distribution of the GLO1 gene that varies from 0.168 in Bania to 0.287 in Brahmin. However, these differences are not statistically significant, and the overall GLO1 frequency in Punjab is well within the North Indian range.  相似文献   
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Data are presented on serological and electrophoretic variants of 18 systems of red cells in 228 individuals belonging to a scheduled tribe (Kanet) and a scheduled caste (Koli) of Kinnar district in Himachal Pradesh, India. Differences in gene frequencies clearly indicate biological distinction in the local population. The possible cause of this genetic heterogeneity is discussed.  相似文献   
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The use of medicinal plants for different therapeutic values is well documented in African continent. African diverse biodiversity hotspots provide a wide range of endemic species, which ensures a potential medicinal value. The feasible conservation approach and sustainable harvesting for the medicinal species remains a huge challenge. However, conservation approach through different biotechnological tools such as micropropagation, somatic embryogenesis, synthetic seed production, hairy root culture, molecular markers based study and cryopreservation of endemic African medicinal species is much crucial. In this review, an attempt has been made to provide different in vitro biotechnological approaches for the conservation of African medicinal species. The present review will be helpful in further technology development and deciding the priorities at decision-making levels for in vitro conservation and sustainable use of African medicinal species.  相似文献   
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The Indian subcontinent shows high levels of seasonal weather variation, but the extent to which mating-related traits (mating latency, copulation duration and number of progeny produced) are being affected by such variations in Drosophila species remain poorly understood. In the present study, we analyzed the effects of seasonal change (humidity and temperature) on mating-related traits of Drosophila melanogaster by mimicking natural conditions in the laboratory. The light body color phenotype is collected in large numbers during the rainy season, while the dark phenotype is prevalent in the winter. We found that a short-term stress, in the form of reduced humidity or temperature, causes a strong climatic selection pressure, which leads to assortative mating and longer copulation duration of the dark phenotype. By contrast, the light phenotype shows higher assortative mating and longer copulation duration after short-term high humidity or high temperature stress. Higher assortative mating and increased copulation duration results in high progeny numbers which may be a cause for the high prevalence of the dark phenotype in winter and the light phenotype in the rainy season. Thus, besides plasticity, seasonal changes in mating propensity can be a potential cause of the change in the frequency of the dark and light phenotypes of D. melanogaster during different seasons.  相似文献   
8.
This study deals with anilofos tolerance and its mineralization by the common rice field cyanobacterium Synechocystis sp. strain PUPCCC 64. The organism tolerated anilofos up to 25 mg L−1. The herbicide caused inhibitory effects on photosynthetic pigments of the test organism in a dose-dependent manner. The organism exhibited 60, 89, 96, 85 and 79% decrease in chlorophyll a, carotenoids, phycocyanin, allophycocyanin and phycoerythrin, respectively, in 20 mg L−1 anilofos on day six. Activities of superoxide dismutase, catalase and peroxidase increased by 1.04 to 1.80 times over control cultures in presence of 20 mg L−1 anilofos. Glutathione content decreased by 26% while proline content was unaffected by 20 mg L−1 anilofos. The test organism showed intracellular uptake and metabolized the herbicide. Uptake of herbicide by test organism was fast during initial six hours followed by slow uptake until 120 hours. The organism exhibited maximum anilofos removal at 100 mg protein L−1, pH 8.0 and 30°C. Its growth in phosphate deficient basal medium in the presence of anilofos (2.5 mg L−1) indicated that herbicide was used by the strain PUPCCC 64 as a source of phosphate.  相似文献   
9.
The thermostable bifunctional CMCase and xylanase encoding gene (rBhcell-xyl) from Bacillus halodurans TSLV1 has been expressed in Escherichia coli. The recombinant E. coli produced rBhcell-xyl (CMCase 2272 and 910 U L?1 xylanase). The rBhcell-xyl is a ~62-kDa monomeric protein with temperature and pH optima of 60 °C and 6.0 with T1/2 of 7.0 and 3.5 h at 80 °C for CMCase and xylanase, respectively. The apparent K m values (CMC and Birchwood xylan) are 3.8 and 3.2 mg mL?1. The catalytic efficiency (k cat/K m ) values of xylanase and CMCase are 657 and 171 mL mg?1 min?1, respectively. End-product analysis confirmed that rBhcell-xyl is a unique endo-acting enzyme with exoglucanase activity. The rBhcell-xyl is a GH5 family enzyme possessing single catalytic module and carbohydrate binding module. The action of rBhcell-xyl on corn cobs and wheat bran liberated reducing sugars, which can be fermented to bioethanol and fine biochemicals.  相似文献   
10.
Background:Use of electronic cigarettes (e-cigarettes) among adolescents has not been fully described, in particular their motivations for using them and factors associated with use. We sought to evaluate the frequency, motivations and associated factors for e-cigarette use among adolescents in Ontario.Methods:We conducted a cross-sectional study in the Niagara region of Ontario, Canada, involving universal screening of students enrolled in grade 9 in co-operation with the Heart Niagara Inc. Healthy Heart Schools’ Program (for the 2013–2014 school year). We used a questionnaire to assess cigarette, e-cigarette and other tobacco use, and self-rated health and stress. We assessed household income using 2011 Canadian census data by matching postal codes to census code.Results:Of 3312 respondents, 2367 answered at least 1 question in the smoking section of the questionnaire (1274 of the 2367 respondents [53.8%] were male, with a mean [SD] age of 14.6 [0.5] yr) and 2292 answered the question about use of e-cigarettes. Most respondents to the questions about use of e-cigarettes (n = 1599, 69.8%) had heard of e-cigarettes, and 380 (23.8%) of these respondents had learned about them from a store sign or display. Use of e-cigarettes was reported by 238 (10.4%) students. Most of the respondents who reported using e-cigarettes (171, 71.9%) tried them because it was “cool/fun/new,” whereas 14 (5.8%) reported using them for smoking reduction or cessation. Male sex, recent cigarette or other tobacco use, family members who smoke and friends who smoke were strongly associated with reported e-cigarette use. Reported use of e-cigarettes was associated with self-identified fair/poor health rating (odds ratio [OR] 1.9 (95% confidence interval [CI] 1.2–3.0), p < 0.001), high stress level (OR 1.7 (95% CI 1.1–2.7), p < 0.001) and lower mean (33.4 [8.4] × $1000 v. 36.1 [10.7] × $1000, p = 0.001) and median [interquartile range] (26.2 [5.6] × $1000 v. 28.1 [5.7] × $1000) household incomes.Interpretation:Use of e-cigarettes is common among adolescents in the Niagara region and is associated with sociodemographic features. Engaging in seemingly exciting new behaviours appears to be a key motivating factor rather than smoking cessation.Electronic cigarettes (e-cigarettes) are novel devices that are designed to mimic the physical and tactile experience of conventional cigarettes while producing a smoke-free vapour. They have quickly gained popularity despite limited evidence regarding the health risks associated with their use and a lack of regulation.1 In addition, existing literature about e-cigarettes suggests that they may not be effective for achieving smoking reduction or cessation, a use for which they are often marketed.13 Given their physical similarities to conventional cigarettes, there are concerns that the increasing use of e-cigarettes may result in the “renormalization” of cigarette smoking.4,5 Previous studies have suggested that use of e-cigarettes among adolescents and young adults may be associated with use of and exposure to tobacco.1,6,7Rates of the use of e-cigarettes at least once among high school students in the United States have increased annually.6,8 Among adolescents in Canada, use of e-cigarettes is now more common than cigarette use.9 However, questions still remain regarding the motivations and factors associated with e-cigarette use among adolescents. Therefore, we sought to evaluate the frequency, motivations and associated factors for use of e-cigarettes by students in grade 9 who were undergoing universal school-based screening for cardiovascular risk factors in the Niagara region in Ontario.  相似文献   
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