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   4321935篇
  免费   349203篇
  国内免费   14571篇
耳鼻咽喉   60228篇
儿科学   139247篇
妇产科学   114136篇
基础医学   663531篇
口腔科学   117830篇
临床医学   394275篇
内科学   781687篇
皮肤病学   107658篇
神经病学   367037篇
特种医学   169219篇
外国民族医学   753篇
外科学   654037篇
综合类   121072篇
现状与发展   24篇
一般理论   2614篇
预防医学   355552篇
眼科学   100531篇
药学   306917篇
  21篇
中国医学   11930篇
肿瘤学   217410篇
  2021年   55960篇
  2020年   35797篇
  2019年   58776篇
  2018年   74330篇
  2017年   56616篇
  2016年   62750篇
  2015年   75676篇
  2014年   109921篇
  2013年   175461篇
  2012年   124154篇
  2011年   128862篇
  2010年   125828篇
  2009年   127562篇
  2008年   115091篇
  2007年   122355篇
  2006年   131176篇
  2005年   125259篇
  2004年   126576篇
  2003年   116786篇
  2002年   106034篇
  2001年   166931篇
  2000年   162006篇
  1999年   148666篇
  1998年   71654篇
  1997年   67601篇
  1996年   65621篇
  1995年   61041篇
  1994年   54966篇
  1993年   51009篇
  1992年   106196篇
  1991年   101278篇
  1990年   97066篇
  1989年   94608篇
  1988年   86872篇
  1987年   85113篇
  1986年   79997篇
  1985年   78178篇
  1984年   65079篇
  1983年   57772篇
  1982年   46731篇
  1981年   43406篇
  1980年   40606篇
  1979年   54740篇
  1978年   44416篇
  1977年   39538篇
  1976年   36460篇
  1975年   36485篇
  1974年   39369篇
  1973年   37557篇
  1972年   35263篇
排序方式: 共有10000条查询结果,搜索用时 217 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