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   1296849篇
  免费   101052篇
  国内免费   2040篇
耳鼻咽喉   18777篇
儿科学   45311篇
妇产科学   35751篇
基础医学   185652篇
口腔科学   34102篇
临床医学   112866篇
内科学   261783篇
皮肤病学   28435篇
神经病学   102543篇
特种医学   52090篇
外国民族医学   671篇
外科学   199275篇
综合类   27133篇
现状与发展   1篇
一般理论   380篇
预防医学   96654篇
眼科学   28280篇
药学   95875篇
  2篇
中国医学   2436篇
肿瘤学   71924篇
  2018年   13495篇
  2017年   10259篇
  2016年   11315篇
  2015年   12776篇
  2014年   17721篇
  2013年   26937篇
  2012年   37016篇
  2011年   39164篇
  2010年   23340篇
  2009年   22394篇
  2008年   37640篇
  2007年   40322篇
  2006年   40532篇
  2005年   39488篇
  2004年   38457篇
  2003年   37314篇
  2002年   36600篇
  2001年   64676篇
  2000年   67197篇
  1999年   56977篇
  1998年   15402篇
  1997年   13968篇
  1996年   14378篇
  1995年   13607篇
  1994年   12911篇
  1993年   11947篇
  1992年   44920篇
  1991年   43853篇
  1990年   42585篇
  1989年   40428篇
  1988年   37200篇
  1987年   36547篇
  1986年   33931篇
  1985年   32593篇
  1984年   24345篇
  1983年   20384篇
  1982年   11794篇
  1981年   10756篇
  1980年   9566篇
  1979年   21516篇
  1978年   14931篇
  1977年   12615篇
  1976年   11794篇
  1975年   12741篇
  1974年   14805篇
  1973年   14242篇
  1972年   13064篇
  1971年   11821篇
  1970年   11144篇
  1969年   10108篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Jahn  P. 《Der Onkologe》2020,26(11):1040-1046
Die Onkologie - Die Pflegepersonaluntergrenzen als rote Linien zur Abgrenzung einer gefährlichen Pflegepraxis sind nicht geeignet, die dringend benötigte Trendwende einzuleiten und...  相似文献   
72.
73.
74.
75.
76.

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   
77.

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   
78.
79.
80.
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