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   5611990篇
  免费   423742篇
  国内免费   17069篇
耳鼻咽喉   79720篇
儿科学   181972篇
妇产科学   151819篇
基础医学   824555篇
口腔科学   160465篇
临床医学   516854篇
内科学   1025876篇
皮肤病学   132367篇
神经病学   460836篇
特种医学   217940篇
外国民族医学   1259篇
外科学   842808篇
综合类   156323篇
现状与发展   24篇
一般理论   3013篇
预防医学   461611篇
眼科学   135969篇
药学   402664篇
  26篇
中国医学   15046篇
肿瘤学   281654篇
  2021年   58519篇
  2019年   60707篇
  2018年   79395篇
  2017年   60545篇
  2016年   67345篇
  2015年   79290篇
  2014年   114195篇
  2013年   180865篇
  2012年   161739篇
  2011年   173377篇
  2010年   138873篇
  2009年   136258篇
  2008年   157977篇
  2007年   170871篇
  2006年   176609篇
  2005年   170731篇
  2004年   170558篇
  2003年   159548篇
  2002年   148453篇
  2001年   228081篇
  2000年   225850篇
  1999年   200274篇
  1998年   80148篇
  1997年   73256篇
  1996年   71095篇
  1995年   66525篇
  1994年   60514篇
  1993年   55859篇
  1992年   149284篇
  1991年   144066篇
  1990年   139545篇
  1989年   135824篇
  1988年   125415篇
  1987年   122969篇
  1986年   116397篇
  1985年   113214篇
  1984年   89724篇
  1983年   78813篇
  1982年   55786篇
  1981年   51179篇
  1980年   47954篇
  1979年   80127篇
  1978年   60789篇
  1977年   53504篇
  1976年   49738篇
  1975年   51839篇
  1974年   58889篇
  1973年   56633篇
  1972年   53405篇
  1971年   49505篇
排序方式: 共有10000条查询结果,搜索用时 31 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