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   3450708篇
  免费   304301篇
  国内免费   13483篇
耳鼻咽喉   47551篇
儿科学   109649篇
妇产科学   90113篇
基础医学   547480篇
口腔科学   95044篇
临床医学   325050篇
内科学   610161篇
皮肤病学   92987篇
神经病学   297552篇
特种医学   134807篇
外国民族医学   288篇
外科学   530172篇
综合类   102200篇
现状与发展   59篇
一般理论   2359篇
预防医学   296179篇
眼科学   79334篇
药学   234816篇
  22篇
中国医学   9326篇
肿瘤学   163343篇
  2021年   55654篇
  2020年   37039篇
  2019年   58441篇
  2018年   74044篇
  2017年   57221篇
  2016年   62738篇
  2015年   76818篇
  2014年   111746篇
  2013年   177188篇
  2012年   94809篇
  2011年   95279篇
  2010年   119395篇
  2009年   124632篇
  2008年   82449篇
  2007年   85407篇
  2006年   95684篇
  2005年   90975篇
  2004年   92314篇
  2003年   83028篇
  2002年   72786篇
  2001年   103082篇
  2000年   95444篇
  1999年   95752篇
  1998年   65353篇
  1997年   63212篇
  1996年   61300篇
  1995年   56613篇
  1994年   50696篇
  1993年   47367篇
  1992年   67712篇
  1991年   64938篇
  1990年   61573篇
  1989年   60671篇
  1988年   56498篇
  1987年   55252篇
  1986年   52676篇
  1985年   52252篇
  1984年   48170篇
  1983年   44346篇
  1982年   41725篇
  1981年   39445篇
  1980年   37163篇
  1979年   40654篇
  1978年   36259篇
  1977年   32841篇
  1976年   30127篇
  1975年   29003篇
  1974年   30485篇
  1973年   29597篇
  1972年   27855篇
排序方式: 共有10000条查询结果,搜索用时 15 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