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   2802226篇
  免费   202922篇
  国内免费   9700篇
耳鼻咽喉   37755篇
儿科学   90184篇
妇产科学   77630篇
基础医学   394170篇
口腔科学   76979篇
临床医学   253052篇
内科学   557737篇
皮肤病学   67371篇
神经病学   229291篇
特种医学   107430篇
外国民族医学   791篇
外科学   421344篇
综合类   57554篇
现状与发展   6篇
一般理论   1019篇
预防医学   206620篇
眼科学   62951篇
药学   206402篇
  9篇
中国医学   6929篇
肿瘤学   159624篇
  2021年   21655篇
  2019年   22322篇
  2018年   31973篇
  2017年   24618篇
  2016年   28345篇
  2015年   31882篇
  2014年   43876篇
  2013年   64910篇
  2012年   86168篇
  2011年   90627篇
  2010年   54788篇
  2009年   52606篇
  2008年   84573篇
  2007年   90016篇
  2006年   91450篇
  2005年   87212篇
  2004年   83846篇
  2003年   80985篇
  2002年   78055篇
  2001年   142773篇
  2000年   145936篇
  1999年   122853篇
  1998年   34469篇
  1997年   30441篇
  1996年   30217篇
  1995年   29232篇
  1994年   26771篇
  1993年   24959篇
  1992年   93794篇
  1991年   89719篇
  1990年   86576篇
  1989年   83762篇
  1988年   76596篇
  1987年   74820篇
  1986年   69915篇
  1985年   66450篇
  1984年   49006篇
  1983年   41373篇
  1982年   24112篇
  1981年   21396篇
  1979年   42442篇
  1978年   29569篇
  1977年   25211篇
  1976年   23005篇
  1975年   24615篇
  1974年   28870篇
  1973年   27353篇
  1972年   25734篇
  1971年   23941篇
  1970年   22009篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
63.
64.

Objectives

Expedient extubation after cardiac surgery has been associated with improved outcomes, leading to postoperative extubation frequently during overnight hours. However, recent evidence in a mixed medical-surgical intensive care unit population demonstrated worse outcomes with overnight extubation. This study investigated the impact of overnight extubation in a statewide, multicenter Society of Thoracic Surgeons database.

Methods

Records from 39,812 patients undergoing coronary artery bypass grafting or valve operations (2008-2016) and extubated within 24 hours were stratified according to extubation time between 06:00 and 18:00 (day) or between 18:00 and 6:00 (overnight). Outcomes including reintubation, mortality, and composite morbidity-mortality were evaluated using hierarchical regression models adjusted for Society of Thoracic Surgeons predictive risk scores. To further analyze extubation during the night, a subanalysis stratified patients into 3 groups: 06:00 to 18:00, 18:00 to 24:00, and 24:00 to 06:00.

Results

A total of 20,758 patients were extubated overnight (52.1%) and were slightly older (median age 66 vs 65 years, P < .001) with a longer duration of ventilation (4 vs 7 hours, P < .001). Day and overnight extubation were associated with equivalent operative mortality (1.7% vs 1.7%, P = .880), reintubation (3.7% vs 3.4%, P = .141), and composite morbidity-mortality (8.2% vs 8.0%, P = .314). After risk adjustment, overnight extubation was not associated with any difference in reintubation, mortality, or composite morbidity-mortality. On subanalysis, those extubated between 24:00 and 06:00 exhibited increased composite morbidity-mortality (odds ratio, 1.18; P = .001) but no difference in reintubation or mortality.

Conclusions

Extubation overnight was not associated with increased mortality or reintubation. These results suggest that in the appropriate clinical setting, it is safe to routinely extubate cardiac surgery patients overnight.  相似文献   
65.
66.
67.

Introduction

Several studies demonstrated that simulator-acquired skill transfer to the operating room is incomplete. Our objective was to identify trainee characteristics that predict the transfer of simulator-acquired skill to the operating room.

Methods

Trainees completed baseline assessments including intracorporeal suturing (IS) performance, attentional selectivity, self-reported use of mental skills, and self-reported prior clinical and simulated laparoscopic experience and confidence. Residents then followed proficiency-based laparoscopic skills training, and their skill transfer was assessed on a live-anesthetized porcine model. Predictive characteristics for transfer test performance were assessed using multiple linear regression.

Results

Thirty-eight residents completed the study. Automaticity, attentional selectivity, resident perceived ability with laparoscopy and simulators, and post-training IS performance were predictive of IS performance during the transfer test.

Conclusions

Promoting automaticity, self-efficacy, and attention selectivity may help improve the transfer of simulator-acquired skill. Mental skills training and training to automaticity may therefore be valuable interventions to achieve this goal.  相似文献   
68.
69.
70.
We report a Chinese family with members affected by epidermolytic ichthyosis (EI), caused by KRT gene mutations. The proband was a 14‐year‐old boy who had simultaneous appearance of nephroblastoma and epidermolytic ichthyosis (EI). Both the patient and his mother exhibited the specific clinical and pathological manifestations of EI. We analysed all exons and flanking sequences of the KRT1 and KRT10 genes using PCR, and found that the proband and his mother had a G>C transition at nucleotide position 1432 in exon 7 of KRT1, resulting in an amino acid substitution of glutamate (GAA) to glutamine (CAA) at codon 478 (E478Q). The KRT10 gene had no mutations.  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