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321.
Mounir R. Abi-Said 《Zoology in the Middle East.》2013,59(1):3-14
Abstract Striped Hyaenas (Hyaena hyaena syriaca) remain widely distributed across Lebanon, as revealed from a compilation of sources ranging from newspapers, to oral and official ministerial reports. They were observed in both urban and rural sites, and across non-protected and protected areas in all governorates, except in the densely populated capital Beirut. Interactions between Striped Hyaenas and people were studied in six identified sites representing a range of ecological, socio-economic and conservation-related conditions. Indirect signs determined by transect surveys of Striped Hyaenas, including footprints, hairs and scats, which were conducted from September 2002 to August 2003, indicate differences in the relative abundance of Striped Hyaenas between the different study sites. Very few indirect signs of Striped Hyaenas were noted in the two nature reserves studied, with more signs outside of these reserves in both urban and rural settings. 相似文献
322.
Susanne H. Kirsch Jean-Pierre KnappWolfgang Herrmann Rima Obeid 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(1):68-75
Folates act as essential coenzymes in many biological pathways. Alteration in folate form distribution might have biological significance, especially in relation to certain genetic polymorphisms. We developed a stable-isotope dilution ultra performance liquid chromatography–mass spectrometry (UPLC–MS/MS) method for quantification of the folate forms 5-methyltetrahydrofolate (5-methylTHF), 5-formylTHF, 5,10-methenylTHF, THF, and folic acid in serum. After extraction using an ion exchange and mixed mode solid-phase, samples were separated and detected using an UPLC–MS/MS system. The quantification limits were between 0.17 nmol/L (5-formylTHF) and 1.79 nmol/L (THF), and the assay was linear up to 100 nmol/L (5-methylTHF) and 10 nmol/L (5-formylTHF, 5,10-methenylTHF, THF, and folic acid). The intraassay CVs for 5-methylTHF and 5-formylTHF were 2.0% and 7.2%, respectively. Mean recoveries were between 82.3% for THF and 110.8% for 5,10-methenylTHF. Concentrations of total folate measured by the new method showed a strong correlation with those measured by an immunologic assay (r = 0.939; p < 0.001). The mean total folate from 32 apparently healthy subjects was 18.09 nmol/L, of which 87.23% was 5-methylTHF. Concentrations of homocysteine showed a better correlation to the total folate measured by the new method compared to that obtained by an immunologic assay. We also confirmed that MTHFR polymorphism has a significant effect on folate distribution in this small population of non-supplemented subjects. 相似文献
323.
Homocysteine in relation to C-reactive protein and low-density lipoprotein cholesterol in assessment of cardiovascular risk. 总被引:2,自引:0,他引:2
W Herrmann R Obeid U Hübner M Jouma J Geisel 《Cellular and molecular biology, including cyto-enzymology》2004,50(8):895-901
Coronary vascular disease (CVD) is a chronic, multifactorial disease that occurs often in individuals without known risk factors. We investigated the predictive value of homocysteine (Hcy) in relation to C-reactive protein (CRP) and low-density lipoprotein (LDL)-cholesterol in patients with confirmed coronary disease. The study included 87 German and 92 Syrian patients in addition to 87 German and 64 Syrian control individuals. Patients and controls were of comparable age, lifestyles and cultural background. Patients of both ethnic groups had significantly higher concentrations of Hcy and C-reactive protein compared to the controls. The lipids were higher only in Syrian patients compared to the controls. Elevated concentrations of Hcy or that of CRP (>75th percentiles) were associated with increased probability for CVD. In both population groups, the risk increased markedly in subjects who had elevated concentrations of Hcy and CRP or those who had elevated concentrations of Hcy and LDL-cholesterol. The results emphasize that detemination of Hcy may improve the predictive value of C-reactive protein and the LDL-cholesterol. Measurements of these markers are especially important for identification of patients at high risk for CVD. 相似文献