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   182214篇
  免费   32660篇
  国内免费   2543篇
耳鼻咽喉   5495篇
儿科学   6061篇
妇产科学   2760篇
基础医学   7161篇
口腔科学   2329篇
临床医学   28657篇
内科学   55673篇
皮肤病学   7993篇
神经病学   17013篇
特种医学   7424篇
外科学   46556篇
综合类   392篇
现状与发展   72篇
一般理论   6篇
预防医学   7902篇
眼科学   3711篇
药学   3223篇
中国医学   123篇
肿瘤学   14866篇
  2024年   706篇
  2023年   4985篇
  2022年   1561篇
  2021年   3694篇
  2020年   6337篇
  2019年   2634篇
  2018年   7966篇
  2017年   7773篇
  2016年   8890篇
  2015年   8885篇
  2014年   16110篇
  2013年   16420篇
  2012年   6816篇
  2011年   6926篇
  2010年   11155篇
  2009年   14921篇
  2008年   7095篇
  2007年   5464篇
  2006年   7904篇
  2005年   5289篇
  2004年   4465篇
  2003年   3398篇
  2002年   3405篇
  2001年   4960篇
  2000年   4252篇
  1999年   4272篇
  1998年   4046篇
  1997年   3735篇
  1996年   3632篇
  1995年   3471篇
  1994年   2186篇
  1993年   1810篇
  1992年   2131篇
  1991年   2092篇
  1990年   1714篇
  1989年   1892篇
  1988年   1649篇
  1987年   1455篇
  1986年   1425篇
  1985年   1226篇
  1984年   880篇
  1983年   802篇
  1982年   642篇
  1981年   505篇
  1980年   465篇
  1979年   566篇
  1978年   512篇
  1977年   555篇
  1972年   469篇
  1970年   406篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
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   
32.
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   
33.
34.
35.
A case of Ullrich disease was presented. The patient was a 3-year-old girl with torticollis, generalized muscle weakness and acroatonia since birth. High-arched palate, protruded calcaneus, and mild contracture of proximal joints were also recognized. Intellectual development was normal. Serum level of CPK was slightly increased. In histological and histochemical examinations of quadriceps femoris muscle, proliferated connective tissue, marked variation in the muscle fiber diameter, and a lot of degenerated and regenerated fibers were recognized. Minimal injury easily causes subcutaneous hemorrhage, but no abnormality was found in the structure of collagen.  相似文献   
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