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   571篇
  免费   34篇
  国内免费   2篇
耳鼻咽喉   3篇
儿科学   17篇
妇产科学   7篇
基础医学   107篇
口腔科学   7篇
临床医学   79篇
内科学   79篇
皮肤病学   24篇
神经病学   25篇
特种医学   31篇
外科学   67篇
综合类   14篇
预防医学   54篇
眼科学   19篇
药学   28篇
中国医学   4篇
肿瘤学   42篇
  2021年   4篇
  2019年   5篇
  2018年   11篇
  2017年   7篇
  2016年   5篇
  2015年   15篇
  2014年   12篇
  2013年   26篇
  2012年   29篇
  2011年   23篇
  2010年   28篇
  2009年   11篇
  2008年   28篇
  2007年   19篇
  2006年   21篇
  2005年   23篇
  2004年   25篇
  2003年   14篇
  2002年   13篇
  2001年   15篇
  2000年   16篇
  1999年   12篇
  1998年   8篇
  1997年   10篇
  1996年   8篇
  1995年   11篇
  1994年   5篇
  1993年   4篇
  1992年   15篇
  1991年   13篇
  1990年   16篇
  1989年   7篇
  1988年   13篇
  1987年   11篇
  1986年   12篇
  1985年   9篇
  1984年   10篇
  1983年   4篇
  1981年   4篇
  1980年   4篇
  1978年   4篇
  1977年   7篇
  1975年   5篇
  1973年   4篇
  1971年   4篇
  1969年   5篇
  1967年   5篇
  1966年   5篇
  1930年   4篇
  1929年   5篇
排序方式: 共有607条查询结果,搜索用时 671 毫秒
61.
62.
63.
64.
65.
The mortality of acute superior mesenteric artery occlusion and mesenteric infarction remains high, in part because of the failure to identify the patients with the disorder. A reliable noninvasive diagnostic study may facilitate earlier definitive diagnosis and therapy. Proton magnetic resonance imaging may offer a noninvasive diagnostic alternative. We examined this possibility by using an experimental rabbit model of acute superior mesenteric artery occlusion in this study. Animals were scanned 1 hour after the ischemic insult. Relative intestinal wall signal intensity was increased in experimental (ischemic) animals when compared to sham operated controls on T2-weighted (4.35 +/- 0.5 vs 2.57 +/- 0.31, p less than 0.02) and proton spin density-weighted images (2.1 +/- 0.2 vs 1.4 +/- 0.21, p less than 0.05). Significant increases in image intensity were found on T2-weighted and proton spin density images when compared to control animals. Differences between groups could be further highlighted after the administration of a paramagnetic contrast agent gadolinium diethyltriamine pentacetic acid on T1-weighted images. The data from this preliminary study demonstrate that proton magnetic resonance imaging may be used to discriminate between ischemic and nonischemic small intestine. This noninvasive tool may someday become clinically useful to enhance our diagnostic capabilities when a diagnosis of acute superior mesenteric artery occlusion is being entertained.  相似文献   
66.
67.
A case of hepatic myelolipoma is described, including the angiographic and computed tomographic appearance. Only three such cases have been reported previously.  相似文献   
68.
Summary The occurrence of possible prolonged alterations in plasma levels of cortisol, epinephrine, norepinephrine, selected energy metabolites, and water and electrolyte balance was assessed in six highly trained male marathon runners by measuring blood biochemical constituents on the 10th day before and for the three days following the running of a marathon. Post-race changes in hemoglobin, hematocrit, and protein levels indicated that a hemodilution had occurred, possibly as a result of elevated sodium levels. Epinephrine remained elevated until the second day. Cortisol was depressed on the first and third post-race days while variable levels were observed on the second day. No prolonged alterations were noted in norepinephrine, FFA, glycerol, triglycerides, glucose, lactate, and pyruvate.This work was supported in part by the Air Force Office of Scientific Research, Air Force Systems Command, Grant AFOSR 73-2455  相似文献   
69.
70.
This investigation compared the safety and efficacy of 3- and 5-mg doses of prostaglandin E2 topical gel used for cervical ripening in 60 high-risk obstetric patients before oxytocin induction of labor. Both dosages significantly increased the Bishop score, unrelated to parity or gestational age. Induction time was significantly shortened, and the average maximum amount of oxytocin required was significantly less with the 5-mg dose, but not with the 3-mg dose, when compared with a placebo. Prostaglandin E2 did not influence the cesarean section rate. Uterine contractions were stimulated in 87.5% of the patients who received the drug, and 37.5% went into active labor, suggesting that prostaglandin E2 in these dosages is not an appropriate agent for local cervical ripening.  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