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871.
The Food and Drug Administration (FDA) recently introduced the Exploratory Investigational New Drug Guidance to expedite the clinical evaluation of new therapeutic and imaging agents. Early clinical studies performed under the auspices of this guidance, so-called "Phase 0" trials, have been initiated at the National Cancer Institute to integrate qualified pharmacodynamic biomarker assays into first-in-human cancer clinical trials of molecularly targeted agents. The goal of this integration is to perform molecular proof-of-concept investigations at the earliest stage of cancer drug development. Phase 0 trials do not offer any possibility of patient benefit; instead, intensive, real-time pharmacodynamic and pharmacokinetic analyses of patient tumor samples and/or surrogate tissues are performed to inform subsequent trials. Phase 0 studies do not replace formal Phase I drug safety testing and require a substantial investment of resources in assay development early on; however, they offer the promise of more rational selection of agents for further, large-scale development as well as the molecular identification of potential therapeutic failures early in the development process.  相似文献   
872.
873.
Hydrobiologia - To understand the spatiotemporal overlap in the habitat use of sympatric predators, we studied longitudinal activity and reservoir section and depth use of pike (Esox lucius),...  相似文献   
874.
Deng  Biao  Wang  Xuan  Long  Xing  Fang  Ren  Zhou  Shuangyun  Zhang  Ji  Peng  Xiaolu  An  Zhenyu  Huang  Weixiong  Tang  Wenzhong  Gao  Yining  Yao  Jinyan 《Journal of Plant Growth Regulation》2022,41(6):2386-2405
Journal of Plant Growth Regulation - Gibberellin (GA), auxin (IAA) and brassinosteroid (BR) are indispensable in the process of plant growth and development. Currently, research on the regulatory...  相似文献   
875.
Zhong  Jun  Guo  Kun  Liao  Zheng-Lan  Hu  Shi-Chen  Du  Yu  Ji  Xiang 《Coral reefs (Online)》2022,41(1):53-62
Coral Reefs - Gut microbiota plays an important role in host nutrition, metabolism, immune, and homeostasis. Although there has been extensive research on gut microbiota over the past decade, few...  相似文献   
876.
Wang  Ning  Gao  Qing  Shi  Jie  Yulan  Chen  Ji  Weimeng  Sheng  Xiumei  Zhang  Rui 《Molecular biology reports》2022,49(9):8727-8740
Molecular Biology Reports - During the pathogenesis and progression of diabetes, lipotoxicity is a major threat to the function and survival of pancreatic β-cells. To battle against the...  相似文献   
877.
Liu  Chao  Zhao  Hong  Ji  Zhi-Hong  Yu  Xin-Yu 《Neurochemical research》2022,47(3):762-767

Accumulated evidence demonstrated that an elevated plasma homocysteine level, hyperhomocysteinemia, induced cognitive impairment in animals, elderly and the patients with neurodegenerative diseases. To date, the underlying cellular and molecular mechanisms by which hyperhomocysteinemia induces cognitive impairment has not been clearly defined. The purpose of this study was to investigate the possible cellular and molecular mechanisms behind hyperhomocysteinemia signaling in rat memory impairment. The results from this study demonstrated that hyperhomocysteinemia induced neuronal damage and loss in hippocampal CA3 region and downregulated the cAMP response element-binding protein (CREB) phosphorylation. The findings of this study provide evidence that hyperhomocysteinemia induces rat memory impairment via injuring hippocampal CA3 neurons and downregulating CREB phosphorylation.

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878.
Li  Wen  Liu  Juan  Ji  Li  Tang  Yi  Qin  Jianbing  Zhao  Heyan  Cheng  Xiang  Tian  Meiling  Jin  Guohua  He  Hui 《Neurochemical research》2022,47(3):679-691
Neurochemical Research - Glioma multiforme (GBM) is the most common malignant primary brain tumors. Despite the considerable advances in GBM treatment, it is still one of the most lethal forms of...  相似文献   
879.
Choi  Hye Lim  Seo  Ji Won  Hwang  Myeong Ha  Yu  Chang Yeon  Seong  Eun Soo 《Transgenic research》2022,31(3):381-389

The SAMS (S-adenosylmethionine synthetase) gene is known to play an important role in the mechanism of cold resistance, as overexpression of this gene results in phenotypic changes in T1-generation transgenic plants. Accordingly, this study was conducted to test the expression of the MsSAMS gene in T2-generation transgenic plants and to investigate the resistance of these plants and the function of the transgene in response to various environmental stresses. For the morphological analysis of T2-generation transgenic plants overexpressing the MsSAMS gene, observations using scanning electron microscopy (SEM) were performed. T2-generation transgenic plants were obtained by planting a total of 5 lines, and their characteristics were tested by comparisons with those of the control. SEM revealed that the thickest leaves were produced by the T6 transgenic line—161.24?±?8.05 µm. The number of stomata ranged from 20.00?±?2.65 to 34.00?±?1.00 in the T2-generation transgenic plants, but the control had more stomata. Resistance to various factors, such as low temperature, drought, and oxidative stress, in the T2-generation transgenic plants was also confirmed. Under cold-stress conditions, the T6 transgenic line presented the lowest value (22.73%) of ion leakage, and under drought-stress conditions, compared with the control, the transgenic lines presented lower ion leakage after being treated with various concentrations of mannitol. Even under oxidative-stress conditions, the T2-generation transgenic plants presented ion leakage levels that were 32.91?±?4.24 to 48.33?±?3.54% lower than those of the control after treatment with various concentrations of methyl viologen. Regarding SAMS enzyme activity, as the duration of cold treatment increased, the activity in the transgenic plants tended to decrease and then increase. During 48 h of cold treatment, the control showed a decrease in SAM content, while the T2-generation transgenic plants presented an increase in SAM content, from 13.58?±?1.04 to 22.75?±?1.95 mg protein/g FW. The results suggest that the MsSAMS gene may be important to the mechanisms of resistance to oxidative and drought stresses in addition to its previously known association with cold resistance. Based on these results, it was suggested that the MsSAMS gene, whose expression is induced by cold stress, can serve as a marker of various responses to environmental stresses, because resistance to cold damage and various environmental stresses are stably inherited in the T2 generation.

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880.
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