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   1324066篇
  免费   102570篇
  国内免费   2021篇
耳鼻咽喉   19175篇
儿科学   45793篇
妇产科学   36136篇
基础医学   189277篇
口腔科学   35378篇
临床医学   115713篇
内科学   266537篇
皮肤病学   29263篇
神经病学   105590篇
特种医学   53395篇
外国民族医学   660篇
外科学   202849篇
综合类   27218篇
现状与发展   1篇
一般理论   403篇
预防医学   98859篇
眼科学   28887篇
药学   98048篇
  2篇
中国医学   2498篇
肿瘤学   72975篇
  2018年   14217篇
  2017年   10881篇
  2016年   12086篇
  2015年   13314篇
  2014年   18274篇
  2013年   28240篇
  2012年   38605篇
  2011年   41059篇
  2010年   24372篇
  2009年   22803篇
  2008年   39597篇
  2007年   42343篇
  2006年   42363篇
  2005年   41248篇
  2004年   40259篇
  2003年   39152篇
  2002年   38445篇
  2001年   65719篇
  2000年   68750篇
  1999年   57594篇
  1998年   15564篇
  1997年   14138篇
  1996年   14476篇
  1995年   13679篇
  1994年   12994篇
  1993年   12016篇
  1992年   44759篇
  1991年   43626篇
  1990年   42372篇
  1989年   40329篇
  1988年   37045篇
  1987年   36398篇
  1986年   33794篇
  1985年   32504篇
  1984年   24408篇
  1983年   20482篇
  1982年   11928篇
  1981年   10873篇
  1980年   9695篇
  1979年   21519篇
  1978年   14962篇
  1977年   12682篇
  1976年   11853篇
  1975年   12759篇
  1974年   14776篇
  1973年   14267篇
  1972年   13033篇
  1971年   11806篇
  1970年   11129篇
  1969年   10112篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.

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   
83.

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   
84.
85.
86.
87.
88.
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   
89.
90.
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