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   5345896篇
  免费   419670篇
  国内免费   16036篇
耳鼻咽喉   77571篇
儿科学   170634篇
妇产科学   143828篇
基础医学   792876篇
口腔科学   151927篇
临床医学   492334篇
内科学   969037篇
皮肤病学   125055篇
神经病学   442644篇
特种医学   210593篇
外国民族医学   1291篇
外科学   810879篇
综合类   152056篇
现状与发展   23篇
一般理论   2973篇
预防医学   450277篇
眼科学   129707篇
药学   383743篇
  22篇
中国医学   13644篇
肿瘤学   260488篇
  2021年   55285篇
  2019年   59363篇
  2018年   76839篇
  2017年   58480篇
  2016年   65287篇
  2015年   77192篇
  2014年   112180篇
  2013年   177737篇
  2012年   154162篇
  2011年   164982篇
  2010年   134970篇
  2009年   133424篇
  2008年   150410篇
  2007年   162563篇
  2006年   169214篇
  2005年   164082篇
  2004年   163631篇
  2003年   153141篇
  2002年   143056篇
  2001年   209260篇
  2000年   207528篇
  1999年   185373篇
  1998年   78169篇
  1997年   72095篇
  1996年   64172篇
  1995年   65178篇
  1994年   59250篇
  1993年   54781篇
  1992年   138546篇
  1991年   134825篇
  1990年   129940篇
  1989年   125940篇
  1988年   116664篇
  1987年   114665篇
  1986年   108440篇
  1985年   105955篇
  1984年   85021篇
  1983年   74603篇
  1982年   54128篇
  1981年   49986篇
  1980年   46842篇
  1979年   77104篇
  1978年   59443篇
  1977年   51289篇
  1976年   48422篇
  1975年   49569篇
  1974年   57315篇
  1973年   54945篇
  1972年   51972篇
  1971年   48210篇
排序方式: 共有10000条查询结果,搜索用时 44 毫秒
61.
62.
63.
64.
Major depressive disorder and other neuropsychiatric disorders are often managed with long-term use of antidepressant medication. Fluoxetine, an SSRI antidepressant, is widely used as a first-line treatment for neuropsychiatric disorders. However, fluoxetine has also been shown to increase the risk of metabolic diseases such as non-alcoholic fatty liver disease. Fluoxetine has been shown to increase hepatic lipid accumulation in vivo and in vitro. In addition, fluoxetine has been shown to alter the production of prostaglandins which have also been implicated in the development of non-alcoholic fatty liver disease. The goal of this study was to assess the effect of fluoxetine exposure on the prostaglandin biosynthetic pathway and lipid accumulation in a hepatic cell line (H4-II-E-C3 cells). Fluoxetine treatment increased mRNA expression of prostaglandin biosynthetic enzymes (Ptgs1, Ptgs2, and Ptgds), PPAR gamma (Pparg), and PPAR gamma downstream targets involved in fatty acid uptake (Cd36, Fatp2, and Fatp5) as well as production of 15-deoxy-Δ12,14PGJ2 a PPAR gamma ligand. The effects of fluoxetine to induce lipid accumulation were attenuated with a PTGS1 specific inhibitor (SC-560), whereas inhibition of PTGS2 had no effect. Moreover, SC-560 attenuated 15-deoxy-Δ12,14PGJ2 production and expression of PPAR gamma downstream target genes. Taken together these results suggest that fluoxetine-induced lipid abnormalities appear to be mediated via PTGS1 and its downstream product 15d-PGJ2 and suggest a novel therapeutic target to prevent some of the adverse effects of fluoxetine treatment.  相似文献   
65.
Cognitive Therapy and Research - Despite interest in psychological inflexibility as a marker of suicide risk, no measure of psychological inflexibility specific to SI exists. The present study...  相似文献   
66.
67.
68.
69.
Gestational trophoblastic neoplasia (GTN) patients are treated according to the eight-variable International Federation of Gynaecology and Obstetrics (FIGO) scoring system, that aims to predict first-line single-agent chemotherapy resistance. FIGO is imperfect with one-third of low-risk patients developing disease resistance to first-line single-agent chemotherapy. We aimed to generate simplified models that improve upon FIGO. Logistic regression (LR) and multilayer perceptron (MLP) modelling (n = 4191) generated six models (M1-6). M1, all eight FIGO variables (scored data); M2, all eight FIGO variables (scored and raw data); M3, nonimaging variables (scored data); M4, nonimaging variables (scored and raw data); M5, imaging variables (scored data); and M6, pretreatment hCG (raw data) + imaging variables (scored data). Performance was compared to FIGO using true and false positive rates, positive and negative predictive values, diagnostic odds ratio, receiver operating characteristic (ROC) curves, Bland-Altman calibration plots, decision curve analysis and contingency tables. M1-6 were calibrated and outperformed FIGO on true positive rate and positive predictive value. Using LR and MLP, M1, M2 and M4 generated small improvements to the ROC curve and decision curve analysis. M3, M5 and M6 matched FIGO or performed less well. Compared to FIGO, most (excluding LR M4 and MLP M5) had significant discordance in patient classification (McNemar's test P < .05); 55-112 undertreated, 46-206 overtreated. Statistical modelling yielded only small gains over FIGO performance, arising through recategorisation of treatment-resistant patients, with a significant proportion of under/overtreatment as the available data have been used a priori to allocate primary chemotherapy. Streamlining FIGO should now be the focus.  相似文献   
70.
Heart Failure Reviews - The nitric oxide (NO)–guanylate cyclase (GC)–cyclic guanosine monophosphate (cGMP) pathway plays an important role in cardiovascular, pulmonary and renal...  相似文献   
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