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   4756481篇
  免费   377347篇
  国内免费   15618篇
耳鼻咽喉   67153篇
儿科学   151405篇
妇产科学   126780篇
基础医学   717286篇
口腔科学   133261篇
临床医学   434482篇
内科学   864544篇
皮肤病学   114675篇
神经病学   399428篇
特种医学   186778篇
外国民族医学   901篇
外科学   719145篇
综合类   135981篇
现状与发展   25篇
一般理论   2748篇
预防医学   392841篇
眼科学   111668篇
药学   340191篇
  23篇
中国医学   12825篇
肿瘤学   237306篇
  2021年   56442篇
  2019年   59015篇
  2018年   75244篇
  2017年   57403篇
  2016年   63723篇
  2015年   76366篇
  2014年   110726篇
  2013年   176366篇
  2012年   135099篇
  2011年   141551篇
  2010年   128974篇
  2009年   129676篇
  2008年   127357篇
  2007年   136670篇
  2006年   144625篇
  2005年   138779篇
  2004年   140035篇
  2003年   130134篇
  2002年   119003篇
  2001年   183566篇
  2000年   179408篇
  1999年   162839篇
  1998年   73970篇
  1997年   69233篇
  1996年   67138篇
  1995年   62579篇
  1994年   56628篇
  1993年   52508篇
  1992年   119931篇
  1991年   114899篇
  1990年   110813篇
  1989年   107916篇
  1988年   99620篇
  1987年   97658篇
  1986年   92188篇
  1985年   89861篇
  1984年   73728篇
  1983年   65289篇
  1982年   50301篇
  1981年   46585篇
  1980年   43720篇
  1979年   64888篇
  1978年   51302篇
  1977年   45313篇
  1976年   41833篇
  1975年   42590篇
  1974年   47451篇
  1973年   45440篇
  1972年   42816篇
  1971年   39499篇
排序方式: 共有10000条查询结果,搜索用时 437 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