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   3366058篇
  免费   245500篇
  国内免费   8405篇
耳鼻咽喉   45363篇
儿科学   110914篇
妇产科学   94115篇
基础医学   479217篇
口腔科学   93817篇
临床医学   310701篇
内科学   658139篇
皮肤病学   78945篇
神经病学   275965篇
特种医学   128695篇
外国民族医学   964篇
外科学   495969篇
综合类   69041篇
现状与发展   7篇
一般理论   1447篇
预防医学   265947篇
眼科学   75904篇
药学   246009篇
  12篇
中国医学   6467篇
肿瘤学   182325篇
  2019年   26430篇
  2018年   36770篇
  2017年   28338篇
  2016年   32419篇
  2015年   36832篇
  2014年   50724篇
  2013年   76922篇
  2012年   102342篇
  2011年   108570篇
  2010年   64994篇
  2009年   62488篇
  2008年   101950篇
  2007年   108455篇
  2006年   109665篇
  2005年   105773篇
  2004年   101807篇
  2003年   98123篇
  2002年   94824篇
  2001年   156296篇
  2000年   159945篇
  1999年   135110篇
  1998年   39156篇
  1997年   34969篇
  1996年   35425篇
  1995年   34088篇
  1994年   31422篇
  1993年   29472篇
  1992年   106245篇
  1991年   103128篇
  1990年   99916篇
  1989年   96442篇
  1988年   88949篇
  1987年   87166篇
  1986年   82172篇
  1985年   78311篇
  1984年   58903篇
  1983年   50247篇
  1982年   29966篇
  1981年   26936篇
  1979年   53031篇
  1978年   37960篇
  1977年   32209篇
  1976年   29791篇
  1975年   31903篇
  1974年   38011篇
  1973年   36669篇
  1972年   34517篇
  1971年   32089篇
  1970年   29859篇
  1969年   28503篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
81.

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   
82.
83.
84.

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   
85.
86.
87.
88.
89.
90.
Henna, derived from a combination of natural leaves and coloring additives, is a common decorative dye traditionally used in many Islamic religious celebrations. Para‐phenylenediamine (PPD), a major component of black henna tattoo, is a strong sensitizer and common allergen. We report a case of severe connubial allergic contact dermatitis after black henna heterotransfer in a girl.  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