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   3777篇
  免费   364篇
  国内免费   5篇
耳鼻咽喉   128篇
儿科学   260篇
妇产科学   144篇
基础医学   221篇
口腔科学   196篇
临床医学   364篇
内科学   787篇
皮肤病学   70篇
神经病学   258篇
特种医学   221篇
外科学   872篇
综合类   33篇
预防医学   102篇
眼科学   128篇
药学   183篇
中国医学   3篇
肿瘤学   176篇
  2024年   13篇
  2023年   82篇
  2022年   36篇
  2021年   122篇
  2020年   88篇
  2019年   147篇
  2018年   221篇
  2017年   155篇
  2016年   245篇
  2015年   222篇
  2014年   279篇
  2013年   462篇
  2012年   225篇
  2011年   174篇
  2010年   204篇
  2009年   138篇
  2008年   153篇
  2007年   131篇
  2006年   158篇
  2005年   159篇
  2004年   83篇
  2003年   70篇
  2002年   98篇
  2001年   60篇
  2000年   63篇
  1999年   56篇
  1998年   57篇
  1997年   54篇
  1996年   48篇
  1995年   30篇
  1994年   24篇
  1993年   25篇
  1992年   10篇
  1991年   13篇
  1990年   9篇
  1989年   7篇
  1988年   3篇
  1985年   2篇
  1984年   2篇
  1983年   2篇
  1982年   3篇
  1981年   1篇
  1980年   2篇
  1978年   3篇
  1974年   2篇
  1972年   1篇
  1962年   1篇
  1960年   1篇
  1947年   1篇
  1935年   1篇
排序方式: 共有4146条查询结果,搜索用时 15 毫秒
71.
Background: Oral appliance therapy for obstructive sleep apnea can be helpful in mild and moderate cases. This clinical report evaluates the efficacy of a protocol that predicts an optimal jaw position and describes the response of a young OSA patient to treatment.

Clinical Presentation: A 27-year-old woman was diagnosed with moderate OSA and had an apnea–hypopnea index (AHI) of 25.8/hr. In order to fabricate a custom device, an alternative procedure to determine the optimal protrusion and vertical positioning of the jaw was applied. After a follow-up period of 14 months, her apnea-hypopnea index (AHI) significantly decreased from 25.8 to 1.0 per hr with the appliance. The total number of respiratory events decreased from 211 to 8.

Conclusion: Improved polysomnographic parameters showed that the oral device was efficient in treatment. The advantages of the device in this study are that it is comfortable, economical, and simple to fabricate.  相似文献   
72.
73.
74.
75.
Image quality in non‐contrast‐enhanced (NCE) angiograms is often limited by scan time constraints. An effective solution is to undersample angiographic acquisitions and to recover vessel images with penalized reconstructions. However, conventional methods leverage penalty terms with uniform spatial weighting, which typically yield insufficient suppression of aliasing interference and suboptimal blood/background contrast. Here we propose a two‐stage strategy where a tractographic segmentation is employed to auto‐extract vasculature maps from undersampled data. These maps are then used to incur spatially adaptive sparsity penalties on vascular and background regions. In vivo steady‐state free precession angiograms were acquired in the hand, lower leg and foot. Compared with regular non‐adaptive compressed sensing (CS) reconstructions (CSlow), the proposed strategy improves blood/background contrast by 71.3 ± 28.9% in the hand (mean ± s.d. across acceleration factors 1–8), 30.6 ± 11.3% in the lower leg and 28.1 ± 7.0% in the foot (signed‐rank test, P < 0.05 at each acceleration). The proposed targeted reconstruction can relax trade‐offs between image contrast, resolution and scan efficiency without compromising vessel depiction. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
76.
77.
78.
79.
Eustachian valve (EV) is a vestige of the valve of the inferior vena cava which directs the umbilical vein blood through open foramen ovale in fetal life. Following birth it gradually regresses, but it may persist in variable size, shape, and thickness as a functionless and benign structure. However, there are reports suggesting that persistent EV may not be completely innocent. It has been accused of being a predisposing cause of patent foramen ovale and paradoxical embolism and also interfering with transseptal interventional procedures. It may serve as a site of infective vegetations and be mistaken as a tumor or thrombus. In the present case, an octopus‐like thrombus attached to the EV was delineated with the utility of two‐dimensional and real time three‐dimensional transesophageal echocardiography. EV was considered to play an essential role in preventing potential pulmonary embolism.  相似文献   
80.
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