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   4222379篇
  免费   341505篇
  国内免费   13933篇
耳鼻咽喉   58813篇
儿科学   135054篇
妇产科学   110800篇
基础医学   652789篇
口腔科学   114135篇
临床医学   382949篇
内科学   764036篇
皮肤病学   106362篇
神经病学   350995篇
特种医学   163876篇
外国民族医学   503篇
外科学   649378篇
综合类   119313篇
现状与发展   23篇
一般理论   2564篇
预防医学   353989篇
眼科学   99046篇
药学   295283篇
  26篇
中国医学   11378篇
肿瘤学   206505篇
  2021年   56193篇
  2020年   35684篇
  2019年   58875篇
  2018年   74183篇
  2017年   56575篇
  2016年   62583篇
  2015年   75655篇
  2014年   110228篇
  2013年   175421篇
  2012年   122050篇
  2011年   127588篇
  2010年   125885篇
  2009年   127113篇
  2008年   113670篇
  2007年   121145篇
  2006年   129771篇
  2005年   124798篇
  2004年   124952篇
  2003年   115359篇
  2002年   104552篇
  2001年   149749篇
  2000年   144586篇
  1999年   134374篇
  1998年   70141篇
  1997年   66264篇
  1996年   64460篇
  1995年   59733篇
  1994年   53817篇
  1993年   50066篇
  1992年   96081篇
  1991年   92659篇
  1990年   89077篇
  1989年   86837篇
  1988年   80036篇
  1987年   78520篇
  1986年   73875篇
  1985年   72996篇
  1984年   61672篇
  1983年   55433篇
  1982年   46029篇
  1981年   43128篇
  1980年   40517篇
  1979年   53115篇
  1978年   44052篇
  1977年   38898篇
  1976年   36282篇
  1975年   36286篇
  1974年   39421篇
  1973年   37646篇
  1972年   35249篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
53.
54.
55.
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   
56.
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   
57.
58.
59.
60.
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