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   1774509篇
  免费   126714篇
  国内免费   2478篇
耳鼻咽喉   24921篇
儿科学   60889篇
妇产科学   47387篇
基础医学   259314篇
口腔科学   46584篇
临床医学   152670篇
内科学   348309篇
皮肤病学   38257篇
神经病学   138214篇
特种医学   69769篇
外国民族医学   714篇
外科学   273062篇
综合类   34902篇
现状与发展   1篇
一般理论   480篇
预防医学   135816篇
眼科学   38987篇
药学   131696篇
  2篇
中国医学   3244篇
肿瘤学   98483篇
  2018年   26807篇
  2017年   20773篇
  2016年   23809篇
  2015年   16167篇
  2014年   22237篇
  2013年   34015篇
  2012年   48831篇
  2011年   58061篇
  2010年   36377篇
  2009年   33104篇
  2008年   56421篇
  2007年   61822篇
  2006年   51488篇
  2005年   51571篇
  2004年   50974篇
  2003年   50263篇
  2002年   48535篇
  2001年   82461篇
  2000年   85935篇
  1999年   72235篇
  1998年   19568篇
  1997年   17641篇
  1996年   18211篇
  1995年   17137篇
  1994年   16244篇
  1993年   15098篇
  1992年   56830篇
  1991年   56313篇
  1990年   55195篇
  1989年   52855篇
  1988年   48725篇
  1987年   48042篇
  1986年   44810篇
  1985年   42978篇
  1984年   32021篇
  1983年   27012篇
  1982年   15507篇
  1981年   14144篇
  1979年   29268篇
  1978年   20586篇
  1977年   17373篇
  1976年   16433篇
  1975年   18008篇
  1974年   21228篇
  1973年   20249篇
  1972年   18928篇
  1971年   17539篇
  1970年   16470篇
  1969年   15251篇
  1968年   14048篇
排序方式: 共有10000条查询结果,搜索用时 640 毫秒
101.

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   
102.

Objective

Arch obstruction after the Norwood procedure is common and contributes to mortality. We determined the prevalence, associated factors, and practice variability of arch reintervention and assessed whether arch reintervention is associated with mortality.

Methods

From 2005 to 2017, 593 neonates in the Congenital Heart Surgeons' Society Critical Left Heart Obstruction cohort underwent a Norwood procedure. Median follow-up was 3.7 years. Multivariable parametric models, including a modulated renewal analysis, were performed.

Results

Of the 593 neonates, 146 (25%) underwent 218 reinterventions for arch obstruction after the Norwood procedure: catheter-based (n = 168) or surgical (n = 50) at a median age of 4.3 months (quartile 1-quartile 3, 2.6-5.7). Interdigitation of the distal aortic anastomosis was protective against arch reintervention. Development of ≥ moderate tricuspid valve regurgitation and right ventricular dysfunction at any point was associated with arch reintervention. Nonsignificant variables for arch reintervention included shunt type and preoperative aortic measurements. Surgical arch reintervention was protective against arch reintervention, but transcatheter reintervention was associated with increased reintervention. Arch reintervention was not associated with increased mortality. There was wide institutional variation in incidence of arch reintervention (range, 0-40 reinterventions per 100 years patient follow-up) and in preintervention gradient (range, 0-64 mm Hg).

Conclusions

Interdigitation of the distal aortic anastomosis during the Norwood procedure decreased the risk of arch reintervention. Surgical arch reintervention is more definitive than transcatheter. Arch reintervention after the Norwood procedure is not associated with increased mortality. Serial surveillance for arch obstruction, integrated with changes in right ventricular function and tricuspid valve regurgitation, is recommended after the Norwood procedure to improve outcomes.  相似文献   
103.
104.
105.
106.
107.
108.
Demodex mites are microscopic arachnids found in the normal skin of many mammals. In humans, it is well established that Demodex mite density is higher in patients with the skin condition rosacea, and treatment with acaricidal agents is effective in resolving symptoms. However, pathophysiology of rosacea is complex and multifactorial. In dogs, demodicosis is a significant veterinary issue, particularly the generalized form of the disease which can be fatal if untreated. In each species, clinical and molecular studies have shown that the host’s immunological interactions with Demodex mites are an important, but not fully understood, aspect of how Demodex can live in the skin either as a harmless commensal organism or as a pathogenic agent. This review outlines the role of Demodex mites in humans and dogs, considering morphology, prevalence, symptoms, diagnosis, histology treatment and pathogenesis.  相似文献   
109.
110.
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