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   1262198篇
  免费   96907篇
  国内免费   1568篇
耳鼻咽喉   16338篇
儿科学   41103篇
妇产科学   35041篇
基础医学   189498篇
口腔科学   34772篇
临床医学   117805篇
内科学   246934篇
皮肤病学   27305篇
神经病学   102019篇
特种医学   46870篇
外国民族医学   265篇
外科学   178733篇
综合类   25812篇
现状与发展   3篇
一般理论   577篇
预防医学   104756篇
眼科学   28059篇
药学   92747篇
  6篇
中国医学   2032篇
肿瘤学   69998篇
  2018年   13604篇
  2017年   10448篇
  2016年   11396篇
  2015年   13138篇
  2014年   18085篇
  2013年   27615篇
  2012年   37740篇
  2011年   40136篇
  2010年   23151篇
  2009年   22356篇
  2008年   37953篇
  2007年   40576篇
  2006年   40135篇
  2005年   39269篇
  2004年   37703篇
  2003年   36110篇
  2002年   35000篇
  2001年   56153篇
  2000年   57159篇
  1999年   48185篇
  1998年   13443篇
  1997年   12264篇
  1996年   12683篇
  1995年   11962篇
  1994年   11139篇
  1993年   10370篇
  1992年   38220篇
  1991年   37744篇
  1990年   36521篇
  1989年   35306篇
  1988年   32726篇
  1987年   32093篇
  1986年   30558篇
  1985年   28852篇
  1984年   21958篇
  1983年   19176篇
  1982年   11327篇
  1981年   10284篇
  1979年   20920篇
  1978年   15386篇
  1977年   12743篇
  1976年   11802篇
  1975年   12810篇
  1974年   15594篇
  1973年   15361篇
  1972年   14527篇
  1971年   13569篇
  1970年   12788篇
  1969年   12070篇
  1968年   11240篇
排序方式: 共有10000条查询结果,搜索用时 16 毫秒
31.

Objective

Comparative survival between neoadjuvant chemotherapy and adjuvant chemotherapy for patients with cT2-4N0-1M0 non–small cell lung cancer has not been extensively studied.

Methods

Patients with cT2-4N0-1M0 non–small cell lung cancer who received platinum-based chemotherapy were retrospectively identified. Exclusion criteria included stage IV disease, induction radiotherapy, and targeted therapy. The primary end point was disease-free survival. Secondary end points were overall survival, chemotherapy tolerance, and ability of Response Evaluation Criteria In Solid Tumors response to predict survival. Survival was estimated using the Kaplan–Meier method, compared using the log-rank test and Cox proportional hazards models, and stratified using matched pairs after propensity score matching.

Results

In total, 330 patients met the inclusion criteria (n = 92/group after propensity-score matching; median follow-up, 42 months). Five-year disease-free survival was 49% (95% confidence interval, 39-61) for neoadjuvant chemotherapy versus 48% (95% confidence interval, 38-61) for adjuvant chemotherapy (P = .70). On multivariable analysis, disease-free survival was not associated with neoadjuvant chemotherapy or adjuvant chemotherapy (hazard ratio, 1.1; 95% confidence interval, 0.64-1.90; P = .737), nor was overall survival (hazard ratio, 1.21; 95% confidence interval, 0.63-2.30; P = .572). The neoadjuvant chemotherapy group was more likely to receive full doses and cycles of chemotherapy (P = .014/0.005) and had fewer grade 3 or greater toxicities (P = .001). Response Evaluation Criteria In Solid Tumors response to neoadjuvant chemotherapy was associated with disease-free survival (P = .035); 15% of patients receiving neoadjuvant chemotherapy (14/92) had a major pathologic response.

Conclusions

Timing of chemotherapy, before or after surgery, is not associated with an improvement in overall or disease-free survival among patients with cT2-4N0-1M0 non–small cell lung cancer who undergo complete surgical resection.  相似文献   
32.
33.

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   
34.
35.
36.
37.
38.
39.
40.
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