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   1973242篇
  免费   147903篇
  国内免费   3774篇
耳鼻咽喉   28701篇
儿科学   66541篇
妇产科学   55573篇
基础医学   280797篇
口腔科学   53927篇
临床医学   170730篇
内科学   394036篇
皮肤病学   42484篇
神经病学   156051篇
特种医学   78687篇
外国民族医学   939篇
外科学   305441篇
综合类   42992篇
现状与发展   1篇
一般理论   595篇
预防医学   147836篇
眼科学   44540篇
药学   145122篇
  2篇
中国医学   3872篇
肿瘤学   106052篇
  2018年   20001篇
  2017年   15409篇
  2016年   16784篇
  2015年   19052篇
  2014年   26790篇
  2013年   41218篇
  2012年   56148篇
  2011年   59544篇
  2010年   35836篇
  2009年   34109篇
  2008年   56989篇
  2007年   60941篇
  2006年   61222篇
  2005年   59897篇
  2004年   58037篇
  2003年   56268篇
  2002年   55213篇
  2001年   93318篇
  2000年   96544篇
  1999年   82142篇
  1998年   22664篇
  1997年   20637篇
  1996年   20887篇
  1995年   19660篇
  1994年   18663篇
  1993年   17417篇
  1992年   64802篇
  1991年   63209篇
  1990年   61642篇
  1989年   58833篇
  1988年   54355篇
  1987年   53551篇
  1986年   50369篇
  1985年   48336篇
  1984年   36201篇
  1983年   30653篇
  1982年   18152篇
  1981年   16247篇
  1979年   32933篇
  1978年   22951篇
  1977年   19413篇
  1976年   18297篇
  1975年   19902篇
  1974年   23569篇
  1973年   22651篇
  1972年   21099篇
  1971年   19243篇
  1970年   18390篇
  1969年   16847篇
  1968年   15768篇
排序方式: 共有10000条查询结果,搜索用时 796 毫秒
121.

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   
122.

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   
123.
124.
125.
126.
127.
128.
129.
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   
130.
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