首页 | 官方网站   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   3770160篇
  免费   308621篇
  国内免费   14104篇
医药卫生   4092885篇
  2021年   55473篇
  2020年   35256篇
  2019年   58325篇
  2018年   72560篇
  2017年   55217篇
  2016年   60893篇
  2015年   74742篇
  2014年   109070篇
  2013年   174194篇
  2012年   100976篇
  2011年   103593篇
  2010年   120041篇
  2009年   122837篇
  2008年   89648篇
  2007年   94974篇
  2006年   104092篇
  2005年   99728篇
  2004年   101464篇
  2003年   92182篇
  2002年   81428篇
  2001年   125781篇
  2000年   119672篇
  1999年   114319篇
  1998年   67803篇
  1997年   64758篇
  1996年   62985篇
  1995年   58647篇
  1994年   52543篇
  1993年   49087篇
  1992年   82788篇
  1991年   81117篇
  1990年   77538篇
  1989年   76046篇
  1988年   70322篇
  1987年   69044篇
  1986年   65153篇
  1985年   64826篇
  1984年   56607篇
  1983年   50919篇
  1982年   44360篇
  1981年   41562篇
  1980年   39257篇
  1979年   48035篇
  1978年   40654篇
  1977年   36166篇
  1976年   33916篇
  1975年   33783篇
  1974年   35782篇
  1973年   34270篇
  1972年   31916篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
Vestibular function laboratories utilize a multitude of diagnostic instruments to evaluate a dizzy patient. Caloric irrigators, oculomotor stimuli, and rotational chairs produce a stimulus whose accuracy is required for the patient response to be accurate. Careful attention to everything from cleanliness of equipment to threshold adjustments determine on a daily basis if patient data are going to be correct and useful. Instrumentation specifications that change with time such as speed and temperature must periodically be checked using calibrated instruments.  相似文献   
82.
83.
84.
85.
86.
87.
88.
89.
Esophageal adenocarcinoma is the fastest rising cancer in the United States. It develops from long‐standing gastroesophageal reflux disease which affects >20% of the general population. It carries a very poor prognosis with 5‐year survival <20%. The disease is known to sequentially progress from reflux esophagitis to a metaplastic precursor, Barrett''s esophagus and then onto dysplasia and esophageal adenocarcinoma. However, only few patients with reflux develop Barrett''s esophagus and only a minority of these turn malignant. The reason for this heterogeneity in clinical progression is unknown. To improve patient management, molecular changes which facilitate disease progression must be identified. Animal models can provide a comprehensive functional and anatomic platform for such a study. Rats and mice have been the most widely studied but disease homology with humans has been questioned. No animal model naturally simulates the inflammation to adenocarcinoma progression as in humans, with all models requiring surgical bypass or destruction of existing antireflux mechanisms. Valuable properties of individual models could be utilized to holistically evaluate disease progression. In this review paper, we critically examined the current animal models of Barrett''s esophagus, their differences and homologies with human disease and how they have shaped our current understanding of Barrett''s carcinogenesis.  相似文献   
90.
This study used the National Survey of Ambulatory Surgery (NSAS) database to measure the incidence of and risk factors for symptoms in the ambulatory surgery center and problems within 24 h after isolated carpal tunnel release (CTR). The NSAS contained records on 400,000 adult patients with carpal tunnel syndrome who were treated with CTR in 2006, based on ICD-9 codes. The type of anesthesia used and factors associated with symptoms and problems were sought in bivariate and multivariable statistical analyses. The mean duration of the procedure was 16 ± 8.8 min. Only 5 % were performed under local anesthesia without sedation, 45 % with IV sedation, 28 % regional anesthesia, and 19 % general anesthesia. Symptoms in the ambulatory surgery center or a problem within 24 h after discharge were recorded in 10 % of patients, all of them minor and transient, including difficulties with pain and its treatment. The strongest risk factors were male sex, age of 45 years and older, and participation of an anesthesiologist. Local anesthesia and regional anesthesia were associated with more perioperative symptoms and postoperative problems. Most CTR are performed with some sedation in the United States. CTR is a safe procedure: one in 10 patients will experience a minor issue in the perioperative or immediate postoperative period.  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-23

京公网安备 11010802026262号