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   4746155篇
  免费   369754篇
  国内免费   15605篇
耳鼻咽喉   66549篇
儿科学   152906篇
妇产科学   125714篇
基础医学   719568篇
口腔科学   131657篇
临床医学   435233篇
内科学   862254篇
皮肤病学   116248篇
神经病学   394022篇
特种医学   184945篇
外国民族医学   896篇
外科学   715180篇
综合类   130626篇
现状与发展   24篇
一般理论   2705篇
预防医学   390730篇
眼科学   112037篇
药学   338214篇
  26篇
中国医学   13349篇
肿瘤学   238631篇
  2021年   56723篇
  2019年   59224篇
  2018年   75642篇
  2017年   57705篇
  2016年   64319篇
  2015年   78649篇
  2014年   112650篇
  2013年   177804篇
  2012年   136083篇
  2011年   140950篇
  2010年   129962篇
  2009年   131388篇
  2008年   126331篇
  2007年   135566篇
  2006年   143652篇
  2005年   137398篇
  2004年   138297篇
  2003年   128021篇
  2002年   117706篇
  2001年   185177篇
  2000年   179999篇
  1999年   164852篇
  1998年   74001篇
  1997年   69077篇
  1996年   67072篇
  1995年   62469篇
  1994年   56426篇
  1993年   52263篇
  1992年   121072篇
  1991年   116598篇
  1990年   112601篇
  1989年   109987篇
  1988年   101226篇
  1987年   99093篇
  1986年   93390篇
  1985年   90684篇
  1984年   74010篇
  1983年   65371篇
  1982年   49933篇
  1981年   46171篇
  1980年   43392篇
  1979年   64095篇
  1978年   50510篇
  1977年   44665篇
  1976年   41288篇
  1975年   42605篇
  1974年   46887篇
  1973年   44593篇
  1972年   41947篇
  1971年   38950篇
排序方式: 共有10000条查询结果,搜索用时 203 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