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   5163886篇
  免费   406507篇
  国内免费   16511篇
耳鼻咽喉   73073篇
儿科学   163443篇
妇产科学   136848篇
基础医学   768229篇
口腔科学   145953篇
临床医学   471088篇
内科学   940462篇
皮肤病学   120456篇
神经病学   431864篇
特种医学   203635篇
外国民族医学   1105篇
外科学   783052篇
综合类   149775篇
现状与发展   23篇
一般理论   2861篇
预防医学   430808篇
眼科学   124308篇
药学   368901篇
  24篇
中国医学   13855篇
肿瘤学   257141篇
  2021年   56823篇
  2019年   59600篇
  2018年   83655篇
  2017年   63901篇
  2016年   71591篇
  2015年   77505篇
  2014年   112457篇
  2013年   178328篇
  2012年   146437篇
  2011年   159035篇
  2010年   137317篇
  2009年   135469篇
  2008年   144878篇
  2007年   156406篇
  2006年   155941篇
  2005年   152018篇
  2004年   152330篇
  2003年   142219篇
  2002年   131392篇
  2001年   203537篇
  2000年   201532篇
  1999年   180440篇
  1998年   77530篇
  1997年   71982篇
  1996年   69630篇
  1995年   65502篇
  1994年   59460篇
  1993年   54992篇
  1992年   134665篇
  1991年   129591篇
  1990年   123974篇
  1989年   120659篇
  1988年   111587篇
  1987年   109606篇
  1986年   103761篇
  1985年   100997篇
  1984年   81784篇
  1983年   71772篇
  1982年   52994篇
  1981年   48998篇
  1980年   45877篇
  1979年   72546篇
  1978年   56129篇
  1977年   49220篇
  1976年   45822篇
  1975年   46178篇
  1974年   53288篇
  1973年   51147篇
  1972年   48063篇
  1971年   44170篇
排序方式: 共有10000条查询结果,搜索用时 15 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