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   2457851篇
  免费   203070篇
  国内免费   4280篇
医药卫生   2665201篇
  2018年   26402篇
  2017年   20690篇
  2016年   22969篇
  2015年   25372篇
  2014年   35758篇
  2013年   55048篇
  2012年   73880篇
  2011年   78127篇
  2010年   45756篇
  2009年   43124篇
  2008年   74589篇
  2007年   79232篇
  2006年   79891篇
  2005年   77874篇
  2004年   74882篇
  2003年   72610篇
  2002年   71535篇
  2001年   115523篇
  2000年   120339篇
  1999年   100041篇
  1998年   27198篇
  1997年   24646篇
  1996年   24370篇
  1995年   25044篇
  1994年   23614篇
  1993年   21969篇
  1992年   79761篇
  1991年   76807篇
  1990年   73933篇
  1989年   71219篇
  1988年   66148篇
  1987年   65171篇
  1986年   61633篇
  1985年   58891篇
  1984年   44663篇
  1983年   37960篇
  1982年   23254篇
  1981年   20638篇
  1980年   19354篇
  1979年   41596篇
  1978年   29254篇
  1977年   24624篇
  1976年   23057篇
  1975年   24228篇
  1974年   29887篇
  1973年   28273篇
  1972年   26416篇
  1971年   24363篇
  1970年   22925篇
  1969年   21247篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
We conducted an observational study of serious airway complications, using similar methods to the fourth UK National Audit Project (NAP4) over a period of 1 year across four hospitals in one region in the UK. We also conducted an activity survey over a week, using NAP4 methods to yield an estimate for relevant denominators to help interpret the primary data. There were 17 serious airway complications, defined as: failed airway management leading to cancellation of surgery (eight); airway management in recovery (five); unplanned intensive care admission (three); and unplanned emergency front of neck access (one). There were no reports of death or brain damage. This was an estimate of 0.028% (1 in 3600) complications using the denominator of 61,000 general anaesthetics per year in the region. Complications in patients with ‘predicted easy’ airways were rare (approximately 1 in 14,200), but 45 times more common in those with ‘predicted difficult’ airways (approximately 1 in 315). Airway management in both groups was similar (induction of anaesthesia followed by supraglottic airway or tracheal tube). Use of awake/sedation intubation, videolaryngoscopy and high-flow nasal oxygenation were uncommon even in the predicted difficult airway patients (in 2.7%, 32.4% and 9.5% of patients, respectively). We conclude that the incidence of serious airway complications is at least as high as it was during NAP4. Despite airway prediction being used, this is not informing subsequent management.  相似文献   
82.
83.
84.
85.
86.
87.
Comprehensive evidence regarding the treatment of non-anaemic iron deficiency in patients undergoing valvular heart surgery is lacking. This study aimed to investigate the association between non-anaemic iron deficiency and postoperative outcomes in these patients. We retrospectively analysed 321 patients of which 180 (56%) had iron deficiency (defined as serum ferritin < 100 ng.ml-1 or < 300 ng.ml-1 with transferrin saturation < 20%). While the iron-deficient group had lower pre-operative haemoglobin levels than the non-iron deficient group (median (IQR [range]) 134 (127–141 [120–172]) g.l-1, 143 (133–150 [120–179]) g.l-1, p = 0.001), there was no between-group difference in allogeneic red blood cell transfusion. Median (IQR [range]) days alive and out of hospital at postoperative day 90 was 1 day shorter in the iron-deficient group (80 (77–82 [9–85]) days vs. 81 (79–83 [0–85]) days, p = 0.026). In multivariable analysis, only cardiopulmonary bypass duration (p = 0.032) and intra-operative allogeneic red blood cell transfusion (p = 0.011) were significantly associated with reduced days alive and out of hospital at postoperative day 90. Iron deficiency did not exert any adverse influence on secondary outcomes except length of hospital stay. Our findings indicate that non-anaemic iron deficiency alone is not associated with adverse effects in patients undergoing valvular heart surgery when it does not translate into an increased risk of allogeneic transfusion.  相似文献   
88.
89.
90.
Clinical Oral Investigations - The aim of this study was the analysis of WNT10A variants in seven families of probands with various forms of tooth agenesis and self-reported family history of...  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