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151.
Dexfenfluramine is one of the anorectic drugs that suppresses food intake which acts via inhibition of reuptake of serotonin into brain terminal. Gastrointestinal tract is the main source of peripheral serotonin which is involved in the regulation of gastrointestinal motility. During the use of anorectic drugs, the antioxidant defence is affected especially by reactive oxygen species. The purpose of this study to search: The effect of dexfenfluramine on serotonin levels of ileum and the effect of dexfenfluramine on ileal contractility and oxidative stress. Materials and Methods: Twenty-two adult male Swiss-albino mice were divided two groups (1) Control, (2) Dexfenfluramine treated (i.p. twice a day 0.2 mg kg−1 in 0.2 ml saline solution for 7 days). Animal body weights were recorded at the beginning and at the end of the experimental period. Ileum tissues contractile responses to different concentrations of KCl and acethycholine were recorded on polygraph. In the meantime ileal tissue malondialdehyde, a product of lipid peroxidation, and glutathione, endogenous antioxidant levels were assessed by spectrophotometric methods. Ileal tissue serotonin level determined by immunohistochemical method. Body weights decrease and ileal contractile response of acethycholine increased significantly by dexfenfluramine treatment. Meanwhile, ileum glutathione levels decreased and malondialdehyde levels increased in dexfenfluramine treated group. Immunohistochemical detection showed that ileal serotonin levels increased by dexfenfluramine treatments. As a conclusion, there is a relationship between increased ileal contractility and oxidant status in dexfenfluramine treated animals. These effects can be related by increased serotonin levels which is induced by dexfenfluramine in ileum. (Mol Cell Biochem xxx: 151–157, 2005)  相似文献   
152.
Most of the biological, chemical or physical agents that cause cell death in certain doses and time of exposure may induce either apoptosis or necrosis. This study explores in what ways the genotoxic, cytotoxic and apoptotic effects of diethylstilbestrol (DES), a chemical agent currently used in the treatment of various types of cancer, on the human lymphocytes depend upon the dose and the exposure time. For this purpose, firstly it aims to determine in what dosages and durations of DES treatment, genotoxicity and cytotoxicity in human lymphocytes occur in vitro. Secondly, it explores the effects of DES on sister-chromatid exchanges (SCEs) and apoptosis and their relation with the nitric oxide (NO) levels. Finally, it investigates whether different dosages of DES and duration of treatment with it are correlated with each other. In so doing, we investigated the relationship among the viability, necrosis and apoptosis rates of human lymphocytes which were treated with five different DES concentrations (1, 5, 10, 15 and 20 μM) for 24, 48 and 72 h, DNA fragmentation analysis of these cells, their mean SCE values and NO levels. We concluded that 5 μM DES at 24 h is the most effective dosage that induces typical features of apoptosis in human lymphocytes. Despite the fact that there are many other studies on the effects of DES on the cancer cells, we thought it might be worth looking into the effects of DES on human lymphocytes in vitro. We meant the present study to contribute to the research done in the field of cancer treatment. (Mol Cell Biochem 276: 45–53, 2005)  相似文献   
153.
There have been many encouraging studies on medical treatment of pulmonary hydatid disease due to Echinococcus granulosus infection. Our aims were to demonstrate the safety and efficacy of medical treatment in pulmonary hydatid disease and to describe a pediatric population who would benefit from medical treatment, especially in respect to the diameter of the hydatid cyst. All patients were treated with mebendazole or albendazole. Treatment outcome was defined as cure, improvement or failure. Among 82 patients, 34.1% were cured, 34.1% improved and 31.8% failed. When 102 cysts were individually evaluated, 36.31% were cured, 32.4% improved and 31.3% failed. The cure and the failure rates were statistically insignificant in cysts treated with mebendazole and albendazole; however statistically significantly more cysts were improved with albendazole. The results were statistically insignificant between continuous and cyclic albendazole treatment. The mean size of successfully treated cysts was 5.3+/-3.4 cm, but "failed" for cyst with a mean size of 7.3+/-4.3 cm. There was a positive, weak and statistically significant correlation between the cyst size and treatment results. The major complication was infection. We suggest that selected pediatric patients with uncomplicated pulmonary hydatid cysts sized less than 5 cm should have a trial of medical treatment with a very close follow up.  相似文献   
154.
Increasing evidence suggests that statins may have pleiotropic effects on vascular wall independent of their cholesterol lowering properties. In the present study, we investigated the acute vascular effects of pravastatin, atorvastatin and cerivastatin on rat isolated aortic rings. Statins effectively and comparably relaxed the aortic rings precontracted submaximally with noradrenaline, in a concentration-dependent manner, in which a high potency was observed with cerivastatin. Endothelium removal or incubation of the aortic rings with nitric oxide synthase inhibitor L-NOARG (10(-4) M) and/or cyclooxygenase inhibitor indomethacin (10(-5) M) significantly attenuated the acute vasorelaxation induced by either of statin. Additionally, different from the other two statins, a significant reduction was observed in response to cerivastatin in the presence of KATP channel inhibitor, glibenclamide (10(-5) M) and Na+- K+ ATPase inhibitor, ouabain (10(-4) M). Furthermore, pretreatment of the rings with the cholesterol precursor mevalonate (10(-3) M) significantly inhibited the endothelium-mediated relaxant effects of the statins. Our findings suggest that statins could acutely modulate vascular tone importantly by endothelium-dependent and mevalonate-related pathways.  相似文献   
155.
The ethanolic root extract of Scrophularia lepidota, an endemic plant of the Turkish flora, has been investigated for its anti-protozoal and inhibitory effect towards plasmodial enoyl-ACP reductase (FabI), a key enzyme of fatty acid biosynthesis in Plasmodium falciparum. Chromatographic separation of the extract yielded 10 iridoids (1-10), two of which are new, and a known phenylethanoid glycoside (11). The structures of the new compounds were determined as 3,4-dihydro-methylcatalpol (8) and 6-O-[4'-O-trans-(3,4-dimethoxycinnamoyl)-alpha-L-rhamnopyranosyl]aucubin (scrolepidoside, 9) by spectroscopic means. The remaining metabolites were characterized as catalpol (1), 6-O-methylcatalpol (2), aucubin (3), 6-O-alpha-L-rhamnopyranosyl-aucubin (sinuatol, 4), 6-O-beta-D-xylopyranosylaucubin (5), ajugol (6), ajugoside (7), an iridoid-related aglycone (10) and angoroside C (11). Nine isolates were active against Leishmania donovani, with the new compound 9 being most potent (IC50 6.1 microg/ml). Except for 4, all pure compounds revealed some trypanocidal potential against Trypanosoma brucei rhodesiense (IC50 values 29.3-73.0 microg/ml). Only compound 10 showed moderate anti-plasmodial (IC50 40.6 microg/ml) and FabI enzyme inhibitory activity (IC50 100 microg/ml). 10 is the second natural product inhibiting the fatty acid biosynthesis of Plasmodium falciparum.  相似文献   
156.
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158.
A detailed chemical analysis of a Philippine marine sponge Smenospongia sp. has been performed. This study yielded four new metabolites, 5-bromo-L-tryptophan (1), 5-bromoabrine (2), 5,6-dibromoabrine (3) and 5-bromoindole-3-acetic acid (4). The pyrroloiminoquinone alkaloid, makaluvamine O (5) as well as 5,6-dibromotryptamine (6), aureol (7) and furospinulosin 1 (8) were also isolated. Although 1 and 4 have been synthesized previously, this is the first report on the isolation of these compounds from a natural source. The furanosesterterpene furospinulosin 1 (8) was obtained for the first time from the genus Smenospongia. The structures of all compounds were established by spectroscopic methods (UV, IR, 1D and 2D NMR, MS, [alpha]D). The cytotoxic potential of 1-8 was evaluated in a panel of isogenic HCT-116 human colon tumor cell lines.  相似文献   
159.
Journal of Ethology - The aims of this observational study were to (1) define which animal’s phenotypic characteristics determine social position in the context of a commercial organic farm...  相似文献   
160.
In this article, we imagine a breeding scenario with a population of individuals that have been genotyped but not phenotyped. We derived a computationally efficient statistic that uses this genetic information to measure the reliability of genomic estimated breeding values (GEBV) for a given set of individuals (test set) based on a training set of individuals. We used this reliability measure with a genetic algorithm scheme to find an optimized training set from a larger set of candidate individuals. This subset was phenotyped to create the training set that was used in a genomic selection model to estimate GEBV in the test set. Our results show that, compared to a random sample of the same size, the use of a set of individuals selected by our method improved accuracies. We implemented the proposed training selection methodology on four sets of data on Arabidopsis, wheat, rice and maize. This dynamic model building process that takes genotypes of the individuals in the test sample into account while selecting the training individuals improves the performance of genomic selection models.

Electronic supplementary material

The online version of this article (doi:10.1186/s12711-015-0116-6) contains supplementary material, which is available to authorized users.  相似文献   
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