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   235537篇
  免费   14902篇
  国内免费   990篇
耳鼻咽喉   2526篇
儿科学   6001篇
妇产科学   4426篇
基础医学   29409篇
口腔科学   4322篇
临床医学   24075篇
内科学   49640篇
皮肤病学   3230篇
神经病学   23712篇
特种医学   10126篇
外国民族医学   13篇
外科学   37048篇
综合类   2536篇
现状与发展   1篇
一般理论   177篇
预防医学   16519篇
眼科学   5532篇
药学   15526篇
  1篇
中国医学   320篇
肿瘤学   16289篇
  2023年   1335篇
  2022年   2191篇
  2021年   5336篇
  2020年   3043篇
  2019年   5053篇
  2018年   6054篇
  2017年   4445篇
  2016年   4851篇
  2015年   5735篇
  2014年   8358篇
  2013年   11254篇
  2012年   17281篇
  2011年   18019篇
  2010年   10074篇
  2009年   9323篇
  2008年   15875篇
  2007年   16677篇
  2006年   16209篇
  2005年   16078篇
  2004年   15115篇
  2003年   13802篇
  2002年   13201篇
  2001年   1946篇
  2000年   1443篇
  1999年   2020篇
  1998年   2786篇
  1997年   2216篇
  1996年   1925篇
  1995年   1766篇
  1994年   1532篇
  1993年   1496篇
  1992年   987篇
  1991年   933篇
  1990年   786篇
  1989年   748篇
  1988年   681篇
  1987年   615篇
  1986年   644篇
  1985年   686篇
  1984年   911篇
  1983年   791篇
  1982年   1039篇
  1981年   968篇
  1980年   839篇
  1979年   468篇
  1978年   527篇
  1977年   448篇
  1976年   423篇
  1975年   316篇
  1974年   311篇
排序方式: 共有10000条查询结果,搜索用时 109 毫秒
41.
42.
43.
44.
The objective of this study was to investigate the effect of fluoridated elastomeric ligatures on the microbiology of local dental plaque in vivo. This randomized, prospective, longitudinal, clinical trial had a split-mouth crossover design. The subjects were 30 patients at the beginning of their treatment with fixed orthodontic appliances in the orthodontic departments of the Liverpool and the Sheffield dental hospitals in the United Kingdom. The study consisted of 2 experimental periods of 6 weeks with a washout period between. Fluoridated elastomers were randomly allocated at the first visit to be placed around brackets on tooth numbers 12, 11, 33 or 22, 21, 43. Nonfluoridated elastomers were placed on the contralateral teeth. Standard nonantibacterial fluoridated toothpaste and mouthwash were supplied. After 6 weeks (visit 2), the elastomers were removed, placed in transport media, and plated on agar within 2 hours. Nonfluoridated elastomers were placed on all brackets for 1 visit to allow for a washout period. At visit 3, fluoridated elastomers were placed on the teeth contralateral to those that received them at visit 1. At visit 4, the procedures at visit 2 were repeated. Samples were collected on visits 2 and 4. A logistic regression was performed, with the presence or absence of streptococcal or anaerobic growth as the dependent variable. A mixed-effects analysis of variance was carried out with the percentage of streptococcal or anaerobic bacterial count as the dependent variable. The only significant independent variables were the subject variable (P =<.001) for the percentage of streptococcal and anaerobic bacterial count and the visit variable for the percentage of streptococcal count (P =<.001). The use of fluoridated or nonfluoridated elastomers was not significant for percentage of either streptococcal (P =.288) or anaerobic count (P =.230). Fluoridated elastomers are not effective at reducing local streptococcal or anaerobic bacterial growth after a clinically relevant time in the mouth.  相似文献   
45.
This research was conducted at a summer camp for siblings of children with cancer. The camp is designed to address emotional problems, provide peer interaction and validation, and bolster siblings' self-esteem. Standardized measures assessing posttraumatic stress, anxiety, quality of life, and self-esteem were administered to 77 siblings (ages 6-17) prior to attending camp and again 3 months after camp. From pre- to post-camp, the siblings reported statistically significant decreases in symptoms of posttraumatic stress and anxiety, and statistically significant improvements in quality of life and self-esteem. These preliminary findings are encouraging and suggest the value of camp as a psychological intervention and provide a model for other pediatric cancer facilities designing intervention programs for siblings.  相似文献   
46.
47.
48.
49.

Background  

Skin and soft tissue infections are increasingly prevalent clinical problems, and it is important for health care practitioners to be well trained in how to treat skin abscesses. A realistic model of abscess incision and drainage will allow trainees to learn and practice this basic physician procedure.  相似文献   
50.
Background: Dreaming reported after anesthesia remains a poorly understood phenomenon. Dreaming may be related to light anesthesia and represent near-miss awareness. However, few studies have assessed the relation between dreaming and depth of anesthesia, and their results were inconclusive. Therefore, the authors tested the hypothesis that dreaming during anesthesia is associated with light anesthesia, as evidenced by higher Bispectral Index values during maintenance of anesthesia.

Methods: With approval, 300 consenting healthy patients, aged 18-50 yr, presenting for elective surgery requiring relaxant general anesthesia with a broad range of agents were studied. Patients were interviewed on emergence and 2-4 h postoperatively. The Bispectral Index was recorded from induction until the first interview. Dream content and form were also assessed.

Results: Dreaming was reported by 22% of patients on emergence. There was no difference between dreamers and nondreamers in median Bispectral Index values during maintenance (37 [23-55] vs. 38 [20-59]; P = 0.68) or the time at Bispectral Index values greater than 60 (0 [0-7] vs. 0 [0-31] min; P = 0.38). Dreamers tended to be younger and male, to have high home dream recall, to receive propofol maintenance or regional anesthesia, and to open their eyes sooner after surgery. Most dreams were similar to dreams of sleep and were pleasant, and the content was unrelated to surgery.  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