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   5860175篇
  免费   447780篇
  国内免费   17304篇
耳鼻咽喉   84529篇
儿科学   187773篇
妇产科学   157789篇
基础医学   855429篇
口腔科学   168697篇
临床医学   544569篇
内科学   1070279篇
皮肤病学   133451篇
神经病学   486091篇
特种医学   228912篇
外国民族医学   1828篇
外科学   872796篇
综合类   164330篇
现状与发展   24篇
一般理论   3212篇
预防医学   496401篇
眼科学   142244篇
药学   423707篇
  28篇
中国医学   14971篇
肿瘤学   288199篇
  2021年   58256篇
  2019年   60556篇
  2018年   79305篇
  2017年   60901篇
  2016年   67889篇
  2015年   79511篇
  2014年   114585篇
  2013年   180813篇
  2012年   169040篇
  2011年   181881篇
  2010年   139942篇
  2009年   137324篇
  2008年   166383篇
  2007年   180256篇
  2006年   185562篇
  2005年   179555篇
  2004年   179335篇
  2003年   168710篇
  2002年   157653篇
  2001年   236683篇
  2000年   236185篇
  1999年   209038篇
  1998年   82213篇
  1997年   74987篇
  1996年   72679篇
  1995年   68294篇
  1994年   62293篇
  1993年   57528篇
  1992年   157741篇
  1991年   152581篇
  1990年   147430篇
  1989年   143109篇
  1988年   132470篇
  1987年   130491篇
  1986年   123417篇
  1985年   119928篇
  1984年   94759篇
  1983年   82939篇
  1982年   57645篇
  1981年   53176篇
  1979年   86157篇
  1978年   65052篇
  1977年   56507篇
  1976年   53053篇
  1975年   54748篇
  1974年   63571篇
  1973年   61123篇
  1972年   57572篇
  1971年   53204篇
  1970年   50038篇
排序方式: 共有10000条查询结果,搜索用时 31 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