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   4310891篇
  免费   349195篇
  国内免费   14526篇
耳鼻咽喉   60225篇
儿科学   139042篇
妇产科学   114132篇
基础医学   661400篇
口腔科学   117804篇
临床医学   393142篇
内科学   778801篇
皮肤病学   107599篇
神经病学   365497篇
特种医学   169052篇
外国民族医学   753篇
外科学   653426篇
综合类   120957篇
现状与发展   24篇
一般理论   2613篇
预防医学   354623篇
眼科学   100462篇
药学   306632篇
  21篇
中国医学   11798篇
肿瘤学   216609篇
  2021年   54384篇
  2020年   35796篇
  2019年   58771篇
  2018年   74329篇
  2017年   56616篇
  2016年   62749篇
  2015年   75675篇
  2014年   109919篇
  2013年   175458篇
  2012年   124146篇
  2011年   128860篇
  2010年   125823篇
  2009年   127561篇
  2008年   115088篇
  2007年   122356篇
  2006年   131175篇
  2005年   125257篇
  2004年   126574篇
  2003年   116784篇
  2002年   106031篇
  2001年   166930篇
  2000年   162005篇
  1999年   148664篇
  1998年   71654篇
  1997年   67266篇
  1996年   59707篇
  1995年   60464篇
  1994年   54504篇
  1993年   50535篇
  1992年   106195篇
  1991年   101277篇
  1990年   97063篇
  1989年   94609篇
  1988年   86872篇
  1987年   85112篇
  1986年   79998篇
  1985年   78178篇
  1984年   65079篇
  1983年   57772篇
  1982年   46731篇
  1981年   43406篇
  1980年   40606篇
  1979年   54740篇
  1978年   44415篇
  1977年   39538篇
  1976年   36459篇
  1975年   36484篇
  1974年   39369篇
  1973年   37557篇
  1972年   35264篇
排序方式: 共有10000条查询结果,搜索用时 421 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