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   3691616篇
  免费   320750篇
  国内免费   13700篇
耳鼻咽喉   50899篇
儿科学   118467篇
妇产科学   97345篇
基础医学   580470篇
口腔科学   102737篇
临床医学   330544篇
内科学   658273篇
皮肤病学   95236篇
神经病学   316815篇
特种医学   148626篇
外国民族医学   498篇
外科学   572007篇
综合类   113677篇
现状与发展   23篇
一般理论   2382篇
预防医学   306758篇
眼科学   85672篇
药学   259571篇
  17篇
中国医学   10128篇
肿瘤学   175921篇
  2021年   55107篇
  2020年   35121篇
  2019年   58065篇
  2018年   71525篇
  2017年   54199篇
  2016年   60033篇
  2015年   73944篇
  2014年   108307篇
  2013年   173386篇
  2012年   97820篇
  2011年   98297篇
  2010年   117929篇
  2009年   122143篇
  2008年   85884篇
  2007年   89182篇
  2006年   100127篇
  2005年   95157篇
  2004年   97687篇
  2003年   88140篇
  2002年   77947篇
  2001年   120863篇
  2000年   115155篇
  1999年   111719篇
  1998年   67016篇
  1997年   64588篇
  1996年   62582篇
  1995年   58193篇
  1994年   52348篇
  1993年   48892篇
  1992年   82948篇
  1991年   79411篇
  1990年   75960篇
  1989年   74630篇
  1988年   69456篇
  1987年   68152篇
  1986年   64941篇
  1985年   64823篇
  1984年   56598篇
  1983年   51290篇
  1982年   44765篇
  1981年   41916篇
  1980年   39520篇
  1979年   48970篇
  1978年   40964篇
  1977年   36781篇
  1976年   34080篇
  1975年   32742篇
  1974年   35299篇
  1973年   34006篇
  1972年   31598篇
排序方式: 共有10000条查询结果,搜索用时 78 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