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   163114篇
  免费   31693篇
  国内免费   2485篇
耳鼻咽喉   5363篇
儿科学   5503篇
妇产科学   2520篇
基础医学   4649篇
口腔科学   1699篇
临床医学   27357篇
内科学   50827篇
皮肤病学   7696篇
神经病学   15507篇
特种医学   6808篇
外科学   43009篇
综合类   278篇
现状与发展   72篇
一般理论   3篇
预防医学   7274篇
眼科学   3488篇
药学   1753篇
中国医学   24篇
肿瘤学   13462篇
  2024年   690篇
  2023年   4860篇
  2022年   1369篇
  2021年   3332篇
  2020年   6158篇
  2019年   2336篇
  2018年   7609篇
  2017年   7513篇
  2016年   8606篇
  2015年   8642篇
  2014年   15772篇
  2013年   15951篇
  2012年   6115篇
  2011年   6152篇
  2010年   10741篇
  2009年   14601篇
  2008年   6438篇
  2007年   4736篇
  2006年   7205篇
  2005年   4511篇
  2004年   3812篇
  2003年   2760篇
  2002年   2857篇
  2001年   4034篇
  2000年   3256篇
  1999年   3475篇
  1998年   3825篇
  1997年   3599篇
  1996年   3484篇
  1995年   3324篇
  1994年   2045篇
  1993年   1653篇
  1992年   1527篇
  1991年   1558篇
  1990年   1193篇
  1989年   1305篇
  1988年   1159篇
  1987年   981篇
  1986年   1020篇
  1985年   824篇
  1984年   630篇
  1983年   602篇
  1982年   553篇
  1981年   424篇
  1980年   392篇
  1979年   352篇
  1978年   363篇
  1977年   435篇
  1975年   303篇
  1972年   336篇
排序方式: 共有10000条查询结果,搜索用时 15 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