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   1280651篇
  免费   94689篇
  国内免费   1994篇
耳鼻咽喉   18289篇
儿科学   42384篇
妇产科学   37923篇
基础医学   187928篇
口腔科学   35494篇
临床医学   108651篇
内科学   252900篇
皮肤病学   26565篇
神经病学   99656篇
特种医学   50195篇
外国民族医学   366篇
外科学   198292篇
综合类   26546篇
现状与发展   1篇
一般理论   302篇
预防医学   92917篇
眼科学   29078篇
药学   98279篇
  1篇
中国医学   2503篇
肿瘤学   69064篇
  2018年   11909篇
  2015年   11751篇
  2014年   16156篇
  2013年   24597篇
  2012年   33841篇
  2011年   36228篇
  2010年   21390篇
  2009年   20192篇
  2008年   35286篇
  2007年   38198篇
  2006年   38782篇
  2005年   38063篇
  2004年   36607篇
  2003年   35593篇
  2002年   35109篇
  2001年   58311篇
  2000年   59762篇
  1999年   50867篇
  1998年   14298篇
  1997年   12857篇
  1996年   13130篇
  1995年   12400篇
  1994年   11817篇
  1993年   10914篇
  1992年   41128篇
  1991年   40516篇
  1990年   40034篇
  1989年   38861篇
  1988年   36222篇
  1987年   35468篇
  1986年   33847篇
  1985年   32261篇
  1984年   24008篇
  1983年   20911篇
  1982年   12439篇
  1981年   10964篇
  1980年   10243篇
  1979年   22714篇
  1978年   15940篇
  1977年   13776篇
  1976年   13001篇
  1975年   14235篇
  1974年   16724篇
  1973年   16121篇
  1972年   15347篇
  1971年   14257篇
  1970年   13234篇
  1969年   12748篇
  1968年   11998篇
  1967年   10496篇
排序方式: 共有10000条查询结果,搜索用时 343 毫秒
61.
62.
BackgroundThe aim of this paper is to assess the current state of quality and outcomes measures being reported for hepatic resections in the recent literature.MethodsMedline and PubMed databases were searched for English language articles published between 1 January 2002 and 30 April 2013. Two examiners reviewed each article and relevant citations for appropriateness of inclusion, which excluded papers of liver donor hepatic resections, repeat hepatectomies or meta-analyses. Data were extracted and summarized by two examiners for analysis.ResultsFifty-five studies were identified with suitable reporting to assess peri-operative mortality in hepatic resections. In only 35% (19/55) of the studies was the follow-up time explicitly stated, and in 47% (26/55) of studies peri-operative mortality was limited to in-hospital or 30 days. The time period in which complications were captured was not explicitly stated in 19 out of 28 studies. The remaining studies only captured complications within 30 days of the index operation (8/28). There was a paucity of quality literature addressing truly patient-centred outcomes.ConclusionQuality outcomes after a hepatic resection are inconsistently reported in the literature. Quality outcome studies for a hepatectomy should report mortality and morbidity at a minimum of 90 days after surgery.  相似文献   
63.
64.
65.
66.
Alterations in autophagy are increasingly being recognized in the pathogenesis of proteinopathies like Alzheimer's disease (AD). This study was conducted to evaluate whether melatonin treatment could provide beneficial effects in an Alzheimer model related to tauopathy by improving the autophagic flux and, thereby, prevent cognitive decline. The injection of AAV‐hTauP301L viral vectors and treatment/injection with okadaic acid were used to achieve mouse and human ex vivo, and in vivo tau‐related models. Melatonin (10 μmol/L) impeded oxidative stress, tau hyperphosphorylation, and cell death by restoring autophagy flux in the ex vivo models. In the in vivo studies, intracerebroventricular injection of AAV‐hTauP301L increased oxidative stress, neuroinflammation, and tau hyperphosphorylation in the hippocampus 7 days after the injection, without inducing cognitive impairment; however, when animals were maintained for 28 days, cognitive decline was apparent. Interestingly, late melatonin treatment (10 mg/kg), starting once the alterations mentioned above were established (from day 7 to day 28), reduced oxidative stress, neuroinflammation, tau hyperphosphorylation, and caspase‐3 activation; these observations correlated with restoration of the autophagy flux and memory improvement. This study highlights the importance of autophagic dysregulation in tauopathy and how administration of pharmacological doses of melatonin, once tauopathy is initiated, can restore the autophagy flux, reduce proteinopathy, and prevent cognitive decline. We therefore propose exogenous melatonin supplementation or the development of melatonin derivatives to improve autophagy flux for the treatment of proteinopathies like AD.  相似文献   
67.
68.
69.
70.
TL1A is a TNF‐like cytokine which has been shown to co‐stimulate TH1 and TH17 responses during chronic inflammation. The expression of this novel cytokine has been investigated in inflammatory disorders like rheumatoid arthritis and inflammatory bowel disease, but little is known about expression and induction in psoriasis. Indeed, the pathogenesis in psoriasis is still not fully understood and it is speculated that cytokines other than TNF‐α are important in subsets of patients. Also, for patients with severe disease that are treated with systemic anti‐TNF‐α blockade, novel candidates to be used as disease and response biomarkers are of high interest. Here, we demonstrate TL1A expression in biopsies from psoriatic lesions. Also, we investigated spontaneous and induced TL1A secretion from PBMCs and blood levels from a cohort of psoriasis patients. Here, increased spontaneous secretion from PBMCs was observed as compared to healthy controls and a small subset of patients had highly elevated TL1A in the blood. Interestingly, activation of PBMCs with various cytokines showed a decreased sensitivity for TL1A activation in psoriasis patients compared to healthy controls.TL1A levels in blood and biopsies could not be correlated with disease activity with this patient cohort. Thus, additional large‐scale studies are warranted to investigate TL1A as a biomarker.  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