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   1404篇
  免费   171篇
  国内免费   18篇
耳鼻咽喉   15篇
儿科学   58篇
妇产科学   10篇
基础医学   147篇
口腔科学   15篇
临床医学   182篇
内科学   311篇
皮肤病学   30篇
神经病学   76篇
特种医学   84篇
外科学   307篇
综合类   49篇
现状与发展   20篇
预防医学   85篇
眼科学   33篇
药学   82篇
中国医学   4篇
肿瘤学   85篇
  2023年   43篇
  2021年   23篇
  2020年   26篇
  2019年   17篇
  2018年   58篇
  2017年   48篇
  2016年   35篇
  2015年   47篇
  2014年   45篇
  2013年   58篇
  2012年   26篇
  2011年   49篇
  2010年   52篇
  2009年   69篇
  2008年   47篇
  2007年   35篇
  2006年   39篇
  2005年   40篇
  2004年   34篇
  2003年   24篇
  2002年   24篇
  2001年   32篇
  2000年   27篇
  1999年   28篇
  1998年   31篇
  1997年   35篇
  1996年   48篇
  1995年   30篇
  1994年   18篇
  1993年   25篇
  1992年   16篇
  1991年   40篇
  1990年   37篇
  1989年   39篇
  1988年   33篇
  1987年   36篇
  1986年   38篇
  1985年   29篇
  1984年   17篇
  1983年   17篇
  1982年   10篇
  1980年   9篇
  1978年   18篇
  1977年   12篇
  1976年   14篇
  1975年   7篇
  1974年   9篇
  1973年   9篇
  1972年   7篇
  1971年   10篇
排序方式: 共有1593条查询结果,搜索用时 15 毫秒
1.
2.
BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation.  相似文献   
3.
4.
The clinical and pathophysiological indices were determined in the operative and immediate postoperative periods in 221 patients with various congenital heart diseases, with consideration for the degree of preoperative disorders of hemodynamics. The operations were conducted under conditions of non-inhalation anesthesia and various-level hypothermal protection without perfusion, with exclusion of the heart from circulation for up to 52 minutes. The main complications developing in the operative and postoperative periods were determined. It is proved that the processes of metabolism and blood oxygen-transport function are interlinked in operations conducted under these conditions. It is also proved that the operations are safe and effective.  相似文献   
5.
The authors had 85 patients with various forms of bronchopulmonary aspergillosis under observation; 45 of them were treated by various types of operative interventions. Forty patients were given mycostats. The article describes the indications and contraindications for surgical treatment, the volume of the operative interventions, the postoperative complications and their management.  相似文献   
6.
A randomized controlled trial of sedation in the critically ill   总被引:2,自引:0,他引:2  
A randomized controlled trial comparing: a) a combination of oral chloral hydrate and promethazine to b) a continuous intravenous midazolam infusion, for maintenance sedation in critically ill children, was carried out. The level of sedation was assessed four hourly using a specifically devized sedation scale. Forty-four children entered the study of whom two were subsequently excluded. The number of satisfactory assessments (desired and actual levels of sedation equal) was significantly greater in the chloral hydrate and promethazine group (Chi-squared P <0.01; confidence intervals of the difference 0.06 to 0.20). The number of assessments at level 5 on the sedation scale (patient restless/distressed) was significantly greater in the midazolam group (Chi-squared P <0.05). The total number of satisfactory assessments in the two groups were only 61 and 48% respectively, suggesting that sedation can be considerably improved. Chloral hydrate and promethazine are more effective than midazolam as maintenance sedation in critically ill children. It is possible to prospectively study the efficacy of sedative drugs in critically ill children.  相似文献   
7.
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