首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   9121篇
  免费   409篇
  国内免费   69篇
耳鼻咽喉   83篇
儿科学   173篇
妇产科学   90篇
基础医学   1114篇
口腔科学   139篇
临床医学   614篇
内科学   2251篇
皮肤病学   110篇
神经病学   655篇
特种医学   375篇
外科学   1969篇
综合类   33篇
现状与发展   1篇
预防医学   184篇
眼科学   125篇
药学   565篇
中国医学   11篇
肿瘤学   1107篇
  2023年   70篇
  2022年   134篇
  2021年   203篇
  2020年   123篇
  2019年   167篇
  2018年   204篇
  2017年   170篇
  2016年   231篇
  2015年   233篇
  2014年   299篇
  2013年   352篇
  2012年   554篇
  2011年   600篇
  2010年   377篇
  2009年   336篇
  2008年   559篇
  2007年   605篇
  2006年   602篇
  2005年   595篇
  2004年   620篇
  2003年   560篇
  2002年   539篇
  2001年   111篇
  2000年   83篇
  1999年   119篇
  1998年   118篇
  1997年   100篇
  1996年   98篇
  1995年   82篇
  1994年   77篇
  1993年   69篇
  1992年   87篇
  1991年   70篇
  1990年   69篇
  1989年   49篇
  1988年   44篇
  1987年   45篇
  1986年   39篇
  1985年   29篇
  1984年   29篇
  1983年   23篇
  1982年   18篇
  1981年   15篇
  1980年   13篇
  1979年   10篇
  1978年   19篇
  1976年   5篇
  1974年   7篇
  1971年   7篇
  1966年   5篇
排序方式: 共有9599条查询结果,搜索用时 15 毫秒
111.
112.
113.
114.
115.
ObjectivesTo investigate the expression levels of multiple molecular markers in radical nephrectomy specimens from patients with metastatic renal cell carcinoma (RCC) treated with sorafenib in order to identify factors predicting susceptibility to this agent.Materials and methodsThis study included 45 consecutive patients undergoing radical nephrectomy for clear cell RCC who were diagnosed as having metastatic diseases refractory to cytokine therapy and subsequently treated with sorafenib. Expression levels of 19 molecular markers involved in the regulation of apoptosis, cell cycle, signal transduction, and angiogenesis in primary RCC specimens were measured by immunohistochemical staining.ResultsThere was no molecular marker having significant impact on the prediction of response to sorafenib. However, progression-free survival (PFS) was significantly associated with the expression levels of Bcl-xL and platelet-derived growth factor receptor (PDGFR)-α in addition to the presence of bone metastasis and C-reactive protein level on univariate analysis. Of these significant factors, PDGFR-α expression and the presence of bone metastasis appeared to be independently related to PFS by multivariate analysis. Furthermore, there were significant differences in PFS according to positive numbers of these 2 independent risk factors; that is, disease progression occurred in 2 of 7 patients who were negative for risk factor, 19 of 34 positive for a single risk factor, and 6 of 6 positive for both risk factors.ConclusionsCollectively, these findings suggest that it would be useful to consider expression levels of potential molecular markers, particularly PDGFR-α, as well as clinical parameters to select metastatic RCC patients likely to benefit from treatment with sorafenib.  相似文献   
116.
Pre-filled syringes (PFS) have been in widespread use as an administration device for therapeutic antibodies in recent decades. Generally, the inner barrel and syringe of PFS are coated with silicone oil (SO) for lubrication. Multiple studies have focused on the fact that the SO adsorbs denatured antibody molecules, and induces antibody aggregation. Aggregated antibodies are recognized as a potential risk for evoking immunogenic responses in patients. The characteristics of the aggregated antibody-SO complexes, including their concentration, population, shape, three-dimensional (3D) image, and Fcγ Receptors (FcγRs) activation have been obscurely acknowledged so far. In the present work, we prepared aggregated antibody-SO complexes by agitation and analyzed using multifaceted techniques such as flow imaging, confocal fluorescence microscopy, and cell-based assays for FcγRs activation. The results emphasized that the SO accelerates the increase in sub-visible particles and antibody aggregation. The confocal fluorescence microscopy analysis revealed the high-resolution 3D images of aggregated antibody-SO complexes. The FcγRs reporter cell assay clarified that the pre-mixed and agitated Ab + SO have higher FcγRs activation capability compared to the agitated Ab. Overall, this study advances the view that SO has an effect to increase the risk of agitation-induced aggregated antibody particles.  相似文献   
117.
Background: Inhibition of acetylcholinesterase (AChE), a biomarker of organophosphorous and carbamate exposure in environmental and occupational human health, has been commonly used to identify potential safety liabilities. So far, many environmental chemicals, including drug candidates, food additives, and industrial chemicals, have not been thoroughly evaluated for their inhibitory effects on AChE activity. AChE inhibitors can have therapeutic applications (e.g., tacrine and donepezil) or neurotoxic consequences (e.g., insecticides and nerve agents).Objectives: The objective of the current study was to identify environmental chemicals that inhibit AChE activity using in vitro and in silico models.Methods: To identify AChE inhibitors rapidly and efficiently, we have screened the Toxicology in the 21st Century (Tox21) 10K compound library in a quantitative high-throughput screening (qHTS) platform by using the homogenous cell-based AChE inhibition assay and enzyme-based AChE inhibition assays (with or without microsomes). AChE inhibitors identified from the primary screening were further tested in monolayer or spheroid formed by SH-SY5Y and neural stem cell models. The inhibition and binding modes of these identified compounds were studied with time-dependent enzyme-based AChE inhibition assay and molecular docking, respectively.Results: A group of known AChE inhibitors, such as donepezil, ambenonium dichloride, and tacrine hydrochloride, as well as many previously unreported AChE inhibitors, such as chelerythrine chloride and cilostazol, were identified in this study. Many of these compounds, such as pyrazophos, phosalone, and triazophos, needed metabolic activation. This study identified both reversible (e.g., donepezil and tacrine) and irreversible inhibitors (e.g., chlorpyrifos and bromophos-ethyl). Molecular docking analyses were performed to explain the relative inhibitory potency of selected compounds.Conclusions: Our tiered qHTS approach allowed us to generate a robust and reliable data set to evaluate large sets of environmental compounds for their AChE inhibitory activity. https://doi.org/10.1289/EHP6993  相似文献   
118.
119.
120.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号