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   2160篇
  免费   130篇
  国内免费   5篇
耳鼻咽喉   18篇
儿科学   16篇
妇产科学   20篇
基础医学   223篇
口腔科学   44篇
临床医学   137篇
内科学   427篇
皮肤病学   15篇
神经病学   144篇
特种医学   57篇
外科学   703篇
综合类   16篇
预防医学   83篇
眼科学   57篇
药学   91篇
中国医学   1篇
肿瘤学   243篇
  2023年   11篇
  2022年   12篇
  2021年   24篇
  2020年   24篇
  2019年   30篇
  2018年   37篇
  2017年   41篇
  2016年   37篇
  2015年   39篇
  2014年   56篇
  2013年   57篇
  2012年   79篇
  2011年   85篇
  2010年   48篇
  2009年   56篇
  2008年   92篇
  2007年   77篇
  2006年   79篇
  2005年   97篇
  2004年   82篇
  2003年   74篇
  2002年   96篇
  2001年   87篇
  2000年   75篇
  1999年   81篇
  1998年   25篇
  1997年   26篇
  1996年   27篇
  1995年   25篇
  1994年   22篇
  1993年   13篇
  1992年   58篇
  1991年   73篇
  1990年   82篇
  1989年   68篇
  1988年   65篇
  1987年   57篇
  1986年   61篇
  1985年   44篇
  1984年   42篇
  1983年   39篇
  1982年   8篇
  1981年   8篇
  1979年   18篇
  1978年   12篇
  1977年   13篇
  1976年   3篇
  1975年   3篇
  1967年   4篇
  1966年   9篇
排序方式: 共有2295条查询结果,搜索用时 31 毫秒
1.
2.
3.
4.
Oral appliances (OAs) have demonstrated efficacy in treating obstructive sleep apnea (OSA), but many different OA devices are available. The Japanese Academy of Dental Sleep Medicine supported the use of OAs that advanced the mandible forward and limited mouth opening and suggested an evaluation of their effects in comparison with untreated or CPAP. A systematic search was undertaken in 16 April 2012. The outcome measures of interest were as follows: Apnea Hypopnea Index (AHI), lowest SpO2, arousal index, Epworth Sleepiness Scale (ESS), the SF‐36 Health Survey. We performed this meta‐analysis using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system. Five studies remained eligible after applying the exclusion criteria. Comparing OA and control appliance, OA significantly reduced the weighted mean difference (WMD) in both AHI and the arousal index (favouring OA, AHI: ?7·05 events h?1; 95% CI, ?12·07 to ?2·03; P = 0·006, arousal index: ?6·95 events h?1; 95% CI, ?11·75 to ?2·15; P = 0·005). OAs were significantly less effective at reducing the WMD in AHI and improving lowest SpO2 and SF‐36 than CPAP, (favouring OA, AHI: 6·11 events h?1; 95% CI, 3·24 to 8·98; P = 0·0001, lowest SpO2: ?2·52%; 95% CI, ?4·81 to ?0·23; P = 0·03, SF‐36: ?1·80; 95% CI, ?3·17 to ?042; P = 0·01). Apnea Hypopnea Index and arousal index were significantly improved by OA relative to the untreated disease. Apnea Hypopnea Index, lowest SpO2 and SF‐36 were significantly better with CPAP than with OA. The results of this study suggested that OAs improve OSA compared with untreated. CPAP appears to be more effective in improving OSA than OAs.  相似文献   
5.
6.
OBJECTIVE: The purpose of this study was to clarify the normal findings of arteries in and around the masseter muscle and to present their pathologic changes with the use of color Doppler sonography. STUDY DESIGN: The vascular appearances were examined for the 4 main arteries feeding the masseter muscle in healthy volunteers (n = 38) and patients with inflammation (n = 5) and intramuscular hemangioma (n = 3). The features of these arteries were investigated together with the flow diameter, flow velocities, and arterial resistances. The symmetry indices were also calculated to assess the pathologic changes. RESULTS: The detection rates of the branch from the transverse facial artery, the masseter artery, and the branch from the maxillary or external carotid artery were 98.7%, 21.1%, and 84.2% in healthy volunteers, respectively. The facial artery that feeds the muscle from the inferior part represented 2 patterns according to anatomic variant: the masseteric branch (22.4%) and the main trunk itself (77.6%). The means of the flow diameter, maximum and minimum velocities, resistive index, and pulsatility index in healthy subjects were 1.8 mm, 24.6 cm/s, 5.1 cm/s, 0.80, and 2.51, respectively. In most of the patients with symptoms, the symmetry indices of all measurement values increased in comparison with those of healthy volunteers. CONCLUSION: Color Doppler sonography is useful in describing the arteries in and around the masseter muscle and has the potential of being used to depict the pathologic changes.  相似文献   
7.
After a determination of the frequency of dens invaginatus by means of radiographic observations, various problems of its identification are discussed. The 188 teeth showing a distinct loop-shaped invagination apically on the radiograph were studied for the presence or absence of caries and periapical lesions. It was demonstrated that periapical lesions caused by caries are mostly due to interproximal caries and that the frequency of periapical lesions caused by caries in the dens invaginatus area was less than previously reported. Comments are made on the dens invaginatus cases having periapical lesions without caries and the parameters for future studies.  相似文献   
8.
9.
10.
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