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   4315090篇
  免费   349433篇
  国内免费   14548篇
耳鼻咽喉   60248篇
儿科学   139115篇
妇产科学   114273篇
基础医学   661871篇
口腔科学   117863篇
临床医学   393631篇
内科学   779843篇
皮肤病学   107681篇
神经病学   365808篇
特种医学   169246篇
外国民族医学   753篇
外科学   654065篇
综合类   120994篇
现状与发展   24篇
一般理论   2614篇
预防医学   354816篇
眼科学   100547篇
药学   306960篇
  21篇
中国医学   11802篇
肿瘤学   216896篇
  2021年   54497篇
  2020年   35878篇
  2019年   58847篇
  2018年   74441篇
  2017年   56684篇
  2016年   62827篇
  2015年   75757篇
  2014年   110028篇
  2013年   175577篇
  2012年   124450篇
  2011年   129194篇
  2010年   125959篇
  2009年   127645篇
  2008年   115347篇
  2007年   122667篇
  2006年   131406篇
  2005年   125503篇
  2004年   126780篇
  2003年   116994篇
  2002年   106243篇
  2001年   167014篇
  2000年   162101篇
  1999年   148744篇
  1998年   71688篇
  1997年   67290篇
  1996年   59719篇
  1995年   60478篇
  1994年   54520篇
  1993年   50543篇
  1992年   106256篇
  1991年   101320篇
  1990年   97102篇
  1989年   94664篇
  1988年   86920篇
  1987年   85163篇
  1986年   80048篇
  1985年   78213篇
  1984年   65104篇
  1983年   57787篇
  1982年   46741篇
  1981年   43414篇
  1980年   40612篇
  1979年   54755篇
  1978年   44428篇
  1977年   39549篇
  1976年   36474篇
  1975年   36502篇
  1974年   39390篇
  1973年   37573篇
  1972年   35274篇
排序方式: 共有10000条查询结果,搜索用时 31 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