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   5383447篇
  免费   412310篇
  国内免费   15555篇
耳鼻咽喉   76771篇
儿科学   173911篇
妇产科学   144766篇
基础医学   799996篇
口腔科学   150546篇
临床医学   498250篇
内科学   981382篇
皮肤病学   127516篇
神经病学   444512篇
特种医学   208582篇
外国民族医学   1148篇
外科学   809094篇
综合类   147226篇
现状与发展   24篇
一般理论   3024篇
预防医学   446255篇
眼科学   129565篇
药学   386040篇
  23篇
中国医学   13878篇
肿瘤学   268803篇
  2021年   57359篇
  2019年   59593篇
  2018年   77559篇
  2017年   59175篇
  2016年   65900篇
  2015年   77635篇
  2014年   112186篇
  2013年   177867篇
  2012年   157671篇
  2011年   168987篇
  2010年   136462篇
  2009年   134204篇
  2008年   153958篇
  2007年   166157篇
  2006年   172794篇
  2005年   166729篇
  2004年   166658篇
  2003年   155989篇
  2002年   144703篇
  2001年   215221篇
  2000年   212942篇
  1999年   189591篇
  1998年   77953篇
  1997年   71764篇
  1996年   69914篇
  1995年   65213篇
  1994年   59143篇
  1993年   54712篇
  1992年   140213篇
  1991年   135364篇
  1990年   130999篇
  1989年   127597篇
  1988年   117636篇
  1987年   115317篇
  1986年   108926篇
  1985年   105962篇
  1984年   84547篇
  1983年   74323篇
  1982年   53739篇
  1981年   49683篇
  1980年   46546篇
  1979年   75150篇
  1978年   57996篇
  1977年   50558篇
  1976年   47231篇
  1975年   48895篇
  1974年   55190篇
  1973年   52720篇
  1972年   49629篇
  1971年   46352篇
排序方式: 共有10000条查询结果,搜索用时 796 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