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   1411903篇
  免费   104695篇
  国内免费   2281篇
耳鼻咽喉   20648篇
儿科学   46704篇
妇产科学   41234篇
基础医学   205178篇
口腔科学   39942篇
临床医学   123163篇
内科学   276013篇
皮肤病学   30204篇
神经病学   112921篇
特种医学   56932篇
外国民族医学   390篇
外科学   219797篇
综合类   27298篇
现状与发展   3篇
一般理论   334篇
预防医学   100741篇
眼科学   32514篇
药学   106545篇
  1篇
中国医学   2761篇
肿瘤学   75556篇
  2018年   15186篇
  2017年   12131篇
  2016年   13900篇
  2015年   15757篇
  2014年   20463篇
  2013年   29901篇
  2012年   40222篇
  2011年   42230篇
  2010年   25578篇
  2009年   24120篇
  2008年   41152篇
  2007年   44503篇
  2006年   45224篇
  2005年   44526篇
  2004年   42680篇
  2003年   41736篇
  2002年   41083篇
  2001年   62493篇
  2000年   63858篇
  1999年   54456篇
  1998年   15578篇
  1997年   13977篇
  1996年   14011篇
  1995年   13125篇
  1994年   12414篇
  1993年   11482篇
  1992年   42687篇
  1991年   42020篇
  1990年   41505篇
  1989年   40225篇
  1988年   37372篇
  1987年   36613篇
  1986年   34902篇
  1985年   33307篇
  1984年   24834篇
  1983年   21516篇
  1982年   12878篇
  1981年   11375篇
  1979年   23583篇
  1978年   16579篇
  1977年   14344篇
  1976年   13501篇
  1975年   14975篇
  1974年   17485篇
  1973年   16805篇
  1972年   16059篇
  1971年   14926篇
  1970年   13830篇
  1969年   13310篇
  1968年   12553篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
71.

Background

Arterial vascular anomalies in patients undergoing kidney transplantation (KT) are correlated with a higher incidence of early surgical complications, potentially causing graft loss. Arterial reconstruction allows patients to overcome these surgical challenges, thus minimizing the risk of poor outcomes. The aim of the present study is to retrospectively investigate the safety and effectiveness of the multiple arterial reconstruction technique with a Teflon patch in case of an unavailable aortic patch: to do so, surgical complications, graft function, and patient survival were evaluated.

Methods

During the period January 2009 to August 2016, 202 adult deceased-donor KTs were performed at our center. Group A (n = 27; reconstruction of multiple arteries) and Group B (n = 175; control group) were compared.

Results

No differences were observed between the 2 groups in terms of early postoperative course, with no vascular complication observed in Group A. No vascular patch infections were reported, nor longer cold ischemia time rates. Similarly, long-term survival rates were similar between the 2 groups.

Conclusions

The Teflon-patch arterial reconstruction technique appears to be safe and effective, with an acceptable balance of benefits and potential risks of using a prosthetic material. Studies based on larger series are needed to further validate this approach.  相似文献   
72.
73.
74.
75.
76.
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   
77.
78.
79.
80.
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   
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