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   5873841篇
  免费   450634篇
  国内免费   16780篇
耳鼻咽喉   85367篇
儿科学   188570篇
妇产科学   159243篇
基础医学   858927篇
口腔科学   170358篇
临床医学   543971篇
内科学   1066874篇
皮肤病学   134985篇
神经病学   483764篇
特种医学   230537篇
外国民族医学   1607篇
外科学   882375篇
综合类   168649篇
现状与发展   23篇
一般理论   3230篇
预防医学   497157篇
眼科学   143741篇
药学   422757篇
  22篇
中国医学   14707篇
肿瘤学   284391篇
  2021年   57500篇
  2019年   59730篇
  2018年   78284篇
  2017年   59705篇
  2016年   66733篇
  2015年   78184篇
  2014年   113329篇
  2013年   179080篇
  2012年   168010篇
  2011年   181420篇
  2010年   139458篇
  2009年   136384篇
  2008年   166591篇
  2007年   180544篇
  2006年   186330篇
  2005年   180965篇
  2004年   180687篇
  2003年   169456篇
  2002年   159360篇
  2001年   231372篇
  2000年   230979篇
  1999年   204504篇
  1998年   81448篇
  1997年   74507篇
  1996年   72350篇
  1995年   67924篇
  1994年   61967篇
  1993年   57336篇
  1992年   155689篇
  1991年   151584篇
  1990年   146650篇
  1989年   142241篇
  1988年   132023篇
  1987年   129984篇
  1986年   123511篇
  1985年   120254篇
  1984年   95511篇
  1983年   83629篇
  1982年   58209篇
  1981年   53534篇
  1979年   88499篇
  1978年   66813篇
  1977年   57618篇
  1976年   54510篇
  1975年   56325篇
  1974年   66097篇
  1973年   63573篇
  1972年   60024篇
  1971年   55930篇
  1970年   52204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