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   2877669篇
  免费   249050篇
  国内免费   12808篇
耳鼻咽喉   39793篇
儿科学   91714篇
妇产科学   72484篇
基础医学   477350篇
口腔科学   75759篇
临床医学   261066篇
内科学   487389篇
皮肤病学   83026篇
神经病学   246682篇
特种医学   114547篇
外国民族医学   79篇
外科学   457585篇
综合类   87693篇
现状与发展   23篇
一般理论   2080篇
预防医学   242425篇
眼科学   65645篇
药学   194582篇
  17篇
中国医学   8618篇
肿瘤学   130970篇
  2021年   53578篇
  2020年   34840篇
  2019年   57806篇
  2018年   70340篇
  2017年   53100篇
  2016年   58394篇
  2015年   72912篇
  2014年   107031篇
  2013年   172148篇
  2012年   77553篇
  2011年   76501篇
  2010年   113475篇
  2009年   118236篇
  2008年   62987篇
  2007年   64775篇
  2006年   75614篇
  2005年   71379篇
  2004年   73505篇
  2003年   64831篇
  2002年   54883篇
  2001年   72254篇
  2000年   63771篇
  1999年   69987篇
  1998年   61826篇
  1997年   60337篇
  1996年   58013篇
  1995年   52934篇
  1994年   47059篇
  1993年   44124篇
  1992年   46333篇
  1991年   45891篇
  1990年   43431篇
  1989年   43612篇
  1988年   40390篇
  1987年   39633篇
  1986年   37495篇
  1985年   38498篇
  1984年   38030篇
  1983年   35564篇
  1982年   37425篇
  1981年   35654篇
  1980年   33723篇
  1979年   30218篇
  1978年   29027篇
  1977年   26772篇
  1976年   25001篇
  1975年   24079篇
  1974年   23502篇
  1973年   22513篇
  1972年   21080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