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   5432195篇
  免费   432483篇
  国内免费   16779篇
耳鼻咽喉   79144篇
儿科学   172500篇
妇产科学   144620篇
基础医学   799212篇
口腔科学   152887篇
临床医学   507146篇
内科学   993464篇
皮肤病学   129083篇
神经病学   451074篇
特种医学   212982篇
外国民族医学   1291篇
外科学   828512篇
综合类   152544篇
现状与发展   91篇
一般理论   2973篇
预防医学   458186篇
眼科学   131699篇
药学   384993篇
  27篇
中国医学   13784篇
肿瘤学   265245篇
  2021年   57854篇
  2019年   60006篇
  2018年   79837篇
  2017年   61843篇
  2016年   68915篇
  2015年   80751篇
  2014年   118341篇
  2013年   183755篇
  2012年   156189篇
  2011年   167044篇
  2010年   139151篇
  2009年   138883篇
  2008年   152511篇
  2007年   163990篇
  2006年   171402篇
  2005年   165430篇
  2004年   164599篇
  2003年   153845篇
  2002年   143703篇
  2001年   210500篇
  2000年   208426篇
  1999年   186328篇
  1998年   79466篇
  1997年   73255篇
  1996年   70891篇
  1995年   66494篇
  1994年   60158篇
  1993年   55559篇
  1992年   139271篇
  1991年   135337篇
  1990年   130425篇
  1989年   126473篇
  1988年   117200篇
  1987年   115094篇
  1986年   108887篇
  1985年   106292篇
  1984年   85439篇
  1983年   75112篇
  1982年   54661篇
  1981年   50491篇
  1980年   47358篇
  1979年   77511篇
  1978年   59834篇
  1977年   51774篇
  1976年   48838篇
  1975年   49911篇
  1974年   57583篇
  1973年   55166篇
  1972年   52102篇
  1971年   48362篇
排序方式: 共有10000条查询结果,搜索用时 15 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