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   157878篇
  免费   31466篇
  国内免费   2471篇
耳鼻咽喉   5202篇
儿科学   5440篇
妇产科学   2469篇
基础医学   4179篇
口腔科学   1561篇
临床医学   26899篇
内科学   49258篇
皮肤病学   7560篇
神经病学   15529篇
特种医学   6595篇
外科学   42258篇
综合类   252篇
现状与发展   72篇
预防医学   7145篇
眼科学   3374篇
药学   1506篇
中国医学   41篇
肿瘤学   12475篇
  2024年   685篇
  2023年   4817篇
  2022年   1242篇
  2021年   3155篇
  2020年   6069篇
  2019年   2208篇
  2018年   7477篇
  2017年   7412篇
  2016年   8496篇
  2015年   8504篇
  2014年   15613篇
  2013年   15782篇
  2012年   5710篇
  2011年   5817篇
  2010年   10543篇
  2009年   14446篇
  2008年   6157篇
  2007年   4398篇
  2006年   6893篇
  2005年   4213篇
  2004年   3491篇
  2003年   2510篇
  2002年   2622篇
  2001年   3913篇
  2000年   3121篇
  1999年   3341篇
  1998年   3808篇
  1997年   3612篇
  1996年   3472篇
  1995年   3322篇
  1994年   2069篇
  1993年   1685篇
  1992年   1485篇
  1991年   1499篇
  1990年   1148篇
  1989年   1257篇
  1988年   1100篇
  1987年   917篇
  1986年   945篇
  1985年   757篇
  1984年   605篇
  1983年   573篇
  1982年   564篇
  1981年   451篇
  1980年   399篇
  1979年   340篇
  1978年   362篇
  1977年   420篇
  1975年   302篇
  1972年   317篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
32.
This paper reports the proceedings of the discussion panel assigned to look at clinical aspects of quality in emergency medicine. One of the seven stated objectives of the Academic Emergency Medicine consensus conference on quality in emergency medicine was to educate emergency physicians regarding quality measures and quality improvement as essential aspects of the practice of emergency medicine. Another topic of interest was a discussion of the value of information technology in facilitating quality care in the clinical practice of emergency medicine. It is important to note that this is not intended to be a comprehensive review of this extensive topic, but instead is designed to report the discussion that occurred at this session of the consensus conference.  相似文献   
33.
Objective: The study goal was to compare the laser spot size created using reflective and refractive micromanipulators with a CO2 laser and to determine the sensitivity of spot size to laser power. Study Design and Setting: A CO2 laser and operating microscope (400-mm focal length) was coupled to either a reflective (Cassegrain-like) or refractive micromanipulator. Laser spot size was determined by measuring the region of ablation created by laser irradiation of wood (dry tongue depressors), exposed photographic film, and agar gel using optical micrometry. Laser power varied from 0.5 to 20 W with pulse durations of 0.1 and 0.5 second. Results: The reflective micromanipulator demonstrated overall smaller spot sizes for a given laser power and lower incremental change in spot size with increasing power. The reflective design demonstrated less sensitivity to increases in laser power. Conclusions: Micromanipulator optical design can result in significant differences in laser spot size. The reflective device used in this study demonstrated less sensitivity to increasing laser power. (Otolaryngol Head Neck Surg 2002;126:593-597.)  相似文献   
34.
35.
36.
37.
38.
Abstracts     
  相似文献   
39.
PURPOSE: The beneficial role of elective neck dissection (END) in the management of high-risk cutaneous squamous cell carcinoma (CSCC) of the head and neck remains unproven. Some surgical specialists suggest that END may be beneficial for patients with clinically node-negative (N0) high-risk CSCC, but there are few data to support this claim. We reviewed the available literature regarding the use of END in the management of both CSCC and head and neck SCC (HNSCC). METHODOLOGY: The available medical literature pertaining to END in both CSCC and HNSCC was reviewed using PubMed and Ovid Medline searches. RESULTS: Many surgical specialists recommend that END be routinely performed in patients with N0 HNSCC when the risk of occult metastases is estimated to exceed 20%; however, patients who undergo END have no proven survival benefit over those who are initially staged as N0 and undergo therapeutic neck dissection (TND) after the development of apparent regional disease. There is a lack of data regarding the proper management of regional nodal basins in patients with N0 CSCC. In the absence of evidence-based data, the cutaneous surgeon must rely on clinical judgment to guide the management of patients with N0 high-risk CSCC of the head and neck. CONCLUSIONS: Appropriate work-up for occult nodal disease may occasionally be warranted in patients with high-risk CSCC. END may play a role in only a very limited number of patients with high-risk CSCC.  相似文献   
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