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   5387166篇
  免费   412240篇
  国内免费   15552篇
耳鼻咽喉   76774篇
儿科学   173967篇
妇产科学   144757篇
基础医学   800310篇
口腔科学   150235篇
临床医学   498714篇
内科学   982748篇
皮肤病学   127510篇
神经病学   444584篇
特种医学   208643篇
外国民族医学   1148篇
外科学   809533篇
综合类   147356篇
现状与发展   24篇
一般理论   3023篇
预防医学   447080篇
眼科学   129596篇
药学   386159篇
  25篇
中国医学   13858篇
肿瘤学   268914篇
  2021年   57259篇
  2019年   59505篇
  2018年   77444篇
  2017年   59102篇
  2016年   65814篇
  2015年   77531篇
  2014年   112065篇
  2013年   177727篇
  2012年   157407篇
  2011年   168660篇
  2010年   136315篇
  2009年   134120篇
  2008年   153721篇
  2007年   165929篇
  2006年   172579篇
  2005年   166528篇
  2004年   166502篇
  2003年   155852篇
  2002年   144569篇
  2001年   215214篇
  2000年   212935篇
  1999年   189587篇
  1998年   77956篇
  1997年   71777篇
  1996年   69915篇
  1995年   65218篇
  1994年   59148篇
  1993年   54715篇
  1992年   140203篇
  1991年   135364篇
  1990年   130997篇
  1989年   127594篇
  1988年   117638篇
  1987年   115316篇
  1986年   108927篇
  1985年   105961篇
  1984年   84543篇
  1983年   74321篇
  1982年   53736篇
  1981年   49681篇
  1980年   46545篇
  1979年   75150篇
  1978年   57996篇
  1977年   50557篇
  1976年   47232篇
  1975年   48893篇
  1974年   55289篇
  1973年   52913篇
  1972年   49724篇
  1971年   46469篇
排序方式: 共有10000条查询结果,搜索用时 131 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