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   5774713篇
  免费   445854篇
  国内免费   17704篇
耳鼻咽喉   84130篇
儿科学   182815篇
妇产科学   157570篇
基础医学   839943篇
口腔科学   170294篇
临床医学   526036篇
内科学   1056327篇
皮肤病学   132879篇
神经病学   480135篇
特种医学   228302篇
外国民族医学   1824篇
外科学   870242篇
综合类   169204篇
现状与发展   24篇
一般理论   3153篇
预防医学   480068篇
眼科学   140704篇
药学   418314篇
  22篇
中国医学   14872篇
肿瘤学   281413篇
  2021年   57335篇
  2019年   59812篇
  2018年   77447篇
  2017年   59207篇
  2016年   66344篇
  2015年   78096篇
  2014年   113221篇
  2013年   179156篇
  2012年   159469篇
  2011年   170254篇
  2010年   136122篇
  2009年   134977篇
  2008年   156972篇
  2007年   169916篇
  2006年   176109篇
  2005年   170911篇
  2004年   171290篇
  2003年   161152篇
  2002年   151344篇
  2001年   227750篇
  2000年   227370篇
  1999年   202230篇
  1998年   80659篇
  1997年   74276篇
  1996年   71818篇
  1995年   67433篇
  1994年   61540篇
  1993年   56994篇
  1992年   154442篇
  1991年   149160篇
  1990年   144116篇
  1989年   140268篇
  1988年   130595篇
  1987年   128353篇
  1986年   122794篇
  1985年   119165篇
  1984年   94873篇
  1983年   82876篇
  1982年   58128篇
  1981年   53258篇
  1979年   87975篇
  1978年   66409篇
  1977年   57814篇
  1976年   53835篇
  1975年   56039篇
  1974年   65819篇
  1973年   63465篇
  1972年   60010篇
  1971年   55747篇
  1970年   52444篇
排序方式: 共有10000条查询结果,搜索用时 819 毫秒
61.
62.
63.
64.
65.
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   
66.
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   
67.
68.
69.
70.
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   
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