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   3532651篇
  免费   302319篇
  国内免费   13938篇
耳鼻咽喉   49190篇
儿科学   114205篇
妇产科学   91095篇
基础医学   559098篇
口腔科学   92973篇
临床医学   316470篇
内科学   634568篇
皮肤病学   92990篇
神经病学   302815篇
特种医学   140641篇
外国民族医学   692篇
外科学   549659篇
综合类   103916篇
现状与发展   24篇
一般理论   2385篇
预防医学   294108篇
眼科学   80948篇
药学   244800篇
  20篇
中国医学   9847篇
肿瘤学   168464篇
  2021年   55886篇
  2020年   35717篇
  2019年   58951篇
  2018年   72490篇
  2017年   54969篇
  2016年   60820篇
  2015年   74801篇
  2014年   109444篇
  2013年   175219篇
  2012年   99857篇
  2011年   100724篇
  2010年   119581篇
  2009年   123773篇
  2008年   88092篇
  2007年   92431篇
  2006年   102343篇
  2005年   98117篇
  2004年   99742篇
  2003年   90613篇
  2002年   80424篇
  2001年   110649篇
  2000年   104560篇
  1999年   103447篇
  1998年   66765篇
  1997年   64038篇
  1996年   61872篇
  1995年   57293篇
  1994年   51500篇
  1993年   48009篇
  1992年   73118篇
  1991年   70165篇
  1990年   66589篇
  1989年   65069篇
  1988年   60217篇
  1987年   59026篇
  1986年   55364篇
  1985年   55398篇
  1984年   50013篇
  1983年   45571篇
  1982年   42085篇
  1981年   39869篇
  1980年   37339篇
  1979年   40936篇
  1978年   35844篇
  1977年   32818篇
  1976年   30164篇
  1975年   29073篇
  1974年   29765篇
  1973年   28646篇
  1972年   26601篇
排序方式: 共有10000条查询结果,搜索用时 15 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