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   4895089篇
  免费   383217篇
  国内免费   18041篇
耳鼻咽喉   67655篇
儿科学   155290篇
妇产科学   130881篇
基础医学   734672篇
口腔科学   138630篇
临床医学   451529篇
内科学   885045篇
皮肤病学   117339篇
神经病学   404684篇
特种医学   190004篇
外国民族医学   770篇
外科学   737415篇
综合类   146129篇
现状与发展   24篇
一般理论   2741篇
预防医学   411776篇
眼科学   116681篇
药学   346963篇
  30篇
中国医学   14062篇
肿瘤学   244027篇
  2021年   56975篇
  2019年   59503篇
  2018年   76322篇
  2017年   58413篇
  2016年   64733篇
  2015年   77381篇
  2014年   111995篇
  2013年   178195篇
  2012年   140083篇
  2011年   147934篇
  2010年   131697篇
  2009年   130987篇
  2008年   132489篇
  2007年   142102篇
  2006年   149196篇
  2005年   143795篇
  2004年   144245篇
  2003年   133305篇
  2002年   122223篇
  2001年   186465篇
  2000年   182869篇
  1999年   165485篇
  1998年   75144篇
  1997年   70007篇
  1996年   67654篇
  1995年   63215篇
  1994年   57374篇
  1993年   53207篇
  1992年   122690篇
  1991年   118322篇
  1990年   113884篇
  1989年   110503篇
  1988年   102365篇
  1987年   100233篇
  1986年   95393篇
  1985年   93054篇
  1984年   76265篇
  1983年   67316篇
  1982年   51290篇
  1981年   47515篇
  1980年   44639篇
  1979年   67688篇
  1978年   53113篇
  1977年   46831篇
  1976年   43614篇
  1975年   43863篇
  1974年   49813篇
  1973年   48127篇
  1972年   45246篇
  1971年   41956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.
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