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   35253篇
  免费   1983篇
  国内免费   142篇
耳鼻咽喉   321篇
儿科学   848篇
妇产科学   720篇
基础医学   4426篇
口腔科学   2049篇
临床医学   2436篇
内科学   9184篇
皮肤病学   885篇
神经病学   2975篇
特种医学   714篇
外科学   4958篇
综合类   204篇
一般理论   12篇
预防医学   2495篇
眼科学   998篇
药学   1655篇
中国医学   146篇
肿瘤学   2352篇
  2023年   249篇
  2022年   443篇
  2021年   1205篇
  2020年   678篇
  2019年   1027篇
  2018年   1221篇
  2017年   791篇
  2016年   823篇
  2015年   1057篇
  2014年   1375篇
  2013年   1752篇
  2012年   2838篇
  2011年   3066篇
  2010年   1690篇
  2009年   1483篇
  2008年   2499篇
  2007年   2688篇
  2006年   2412篇
  2005年   2145篇
  2004年   1854篇
  2003年   1682篇
  2002年   1628篇
  2001年   221篇
  2000年   162篇
  1999年   210篇
  1998年   250篇
  1997年   210篇
  1996年   188篇
  1995年   152篇
  1994年   156篇
  1993年   118篇
  1992年   72篇
  1991年   72篇
  1990年   60篇
  1989年   48篇
  1988年   49篇
  1987年   49篇
  1986年   40篇
  1985年   43篇
  1984年   68篇
  1983年   52篇
  1982年   46篇
  1981年   75篇
  1980年   43篇
  1979年   35篇
  1978年   40篇
  1977年   44篇
  1976年   42篇
  1974年   21篇
  1973年   22篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
22.
23.
24.
25.
26.
Cecal intubation is a critical aspect of effective, complete colonoscopy. Difficult colonoscopy is most often considered as one in which it is challenging or impossible to reach the cecum. It may be a common occurrence due to patient and/or endoscopist factors. Incomplete colonoscopies should be avoided, since patients in this context present an important prevalence of lesions that escape examination. The approach to successful cecal intubation should depend on characterization of the problem as redundant colon or difficult sigmoid colon. Most patients with a prior incomplete colonoscopy can be colonoscoped successfully, if careful attention is paid to technique, using a variety of scopes, colonoscopy methods and additional equipment. Sufficient time should be allotted to make the attempt.  相似文献   
27.
28.
Background and study aimsThe COVID-19 outbreak has reorganized surgical team conditions regarding endoscopy. The number of interventions has been reduced, the number of healthcare professionals must be limited, and both the patients and physicians are more protected than ever.Patients and MethodsIn the highest peak of contagion in Colombia, endoscopy, colonoscopy, and esophagogastroduodenoscopy were performed using a low-cost disposable device. A total of 1388 procedures were performed. Every patient was assessed for symptoms via a telephone call, at the health center, and after the procedure, following specific attention routes.ResultsAfter procedure follow-up, no positive cases of COVID-19 were noted.ConclusionThe methodology reduced the risk of infection during the COVID-19 pandemic.  相似文献   
29.
30.
OBJECTIVE: Alveolar distraction is a relatively novel procedure by which alveolar bone and underlying mucosa are regenerated. The low predictability of other vertical or horizontal bone regeneration methods has increased interest in this promising technique. This article was designed to review published clinical and experimental results on alveolar distraction, including basic research in other disciplines (maxillofacial and orthopedic distraction) related to or with influence on alveolar distraction. STUDY DESIGN: A review of the international literature was performed to summarize results of clinical and experimental studies on alveolar distraction and on distraction at other anatomical sites that contribute important findings on tissue biology, molecular mechanisms, and other factors that influence and participate in the alveolar distraction process. RESULTS: Research into alveolar distraction has addressed the latency phase, distraction phase, and consolidation phase, yielding highly variable results. Little experimental research has been carried out on this procedure, and most publications are clinical studies with a short follow-up period. Published studies have reported a high rate of complications, attributable to our current lack of understanding of the process. CONCLUSIONS: Definitive conclusions on alveolar distraction are hampered by the lack of clinical and experimental studies to date. Greater knowledge of the factors that influence the distraction process will lead to a more predictable and efficacious distraction technique and a better distractor design.  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