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   3791312篇
  免费   313640篇
  国内免费   14787篇
耳鼻咽喉   50921篇
儿科学   120037篇
妇产科学   98515篇
基础医学   594099篇
口腔科学   103025篇
临床医学   342708篇
内科学   678222篇
皮肤病学   98858篇
神经病学   318575篇
特种医学   147786篇
外国民族医学   264篇
外科学   585170篇
综合类   114365篇
现状与发展   24篇
一般理论   2397篇
预防医学   310995篇
眼科学   89788篇
药学   263069篇
  23篇
中国医学   11503篇
肿瘤学   189395篇
  2021年   55901篇
  2020年   35588篇
  2019年   58712篇
  2018年   73123篇
  2017年   55436篇
  2016年   61377篇
  2015年   75060篇
  2014年   109493篇
  2013年   175187篇
  2012年   106881篇
  2011年   109141篇
  2010年   121627篇
  2009年   124459篇
  2008年   95761篇
  2007年   100604篇
  2006年   109868篇
  2005年   104731篇
  2004年   106217篇
  2003年   95890篇
  2002年   85234篇
  2001年   136318篇
  2000年   129854篇
  1999年   122236篇
  1998年   68761篇
  1997年   65378篇
  1996年   63076篇
  1995年   58616篇
  1994年   52619篇
  1993年   48962篇
  1992年   85188篇
  1991年   81129篇
  1990年   76794篇
  1989年   75244篇
  1988年   69139篇
  1987年   67337篇
  1986年   63644篇
  1985年   62889篇
  1984年   54979篇
  1983年   49661篇
  1982年   43712篇
  1981年   41068篇
  1980年   38542篇
  1979年   44935篇
  1978年   38294篇
  1977年   34978篇
  1976年   32011篇
  1975年   30870篇
  1974年   32541篇
  1973年   31242篇
  1972年   29082篇
排序方式: 共有10000条查询结果,搜索用时 46 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.
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   
66.
67.
68.
69.
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   
70.
Heart Failure Reviews - The nitric oxide (NO)–guanylate cyclase (GC)–cyclic guanosine monophosphate (cGMP) pathway plays an important role in cardiovascular, pulmonary and renal...  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