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   3257篇
  免费   2篇
电工技术   3篇
综合类   2篇
化学工业   36篇
金属工艺   12篇
机械仪表   9篇
建筑科学   19篇
矿业工程   11篇
能源动力   11篇
轻工业   15篇
水利工程   2篇
石油天然气   3篇
无线电   20篇
一般工业技术   40篇
冶金工业   3056篇
原子能技术   1篇
自动化技术   19篇
  2022年   3篇
  2020年   2篇
  2018年   2篇
  2017年   4篇
  2016年   3篇
  2015年   3篇
  2014年   9篇
  2013年   17篇
  2012年   8篇
  2011年   16篇
  2010年   7篇
  2009年   16篇
  2008年   7篇
  2007年   11篇
  2006年   9篇
  2005年   7篇
  2004年   7篇
  2003年   7篇
  2002年   16篇
  2001年   7篇
  2000年   6篇
  1999年   92篇
  1998年   857篇
  1997年   468篇
  1996年   301篇
  1995年   189篇
  1994年   131篇
  1993年   203篇
  1992年   35篇
  1991年   40篇
  1990年   41篇
  1989年   57篇
  1988年   48篇
  1987年   48篇
  1986年   47篇
  1985年   51篇
  1984年   5篇
  1983年   3篇
  1982年   13篇
  1981年   34篇
  1980年   34篇
  1979年   2篇
  1978年   7篇
  1977年   108篇
  1976年   250篇
  1975年   15篇
  1972年   2篇
  1968年   1篇
  1963年   1篇
  1955年   4篇
排序方式: 共有3259条查询结果,搜索用时 0 毫秒
991.
992.
993.
994.
995.
996.
997.
998.
999.
OBJECTIVE: To determine the outcome of very elderly patients who had coronary revascularization during hospitalization for an acute myocardial infarction. DESIGN: Retrospective cohort study. SETTING: Community-based tertiary-care teaching hospital. PATIENTS: A total of 1215 consecutive patients 80 years and older were hospitalized with a myocardial infarction between 1985 and 1990. The study sample included all 93 patients (8%) who had cardiac catheterization before discharge and had not been excluded from study because of the following: severe valvular disease, absence of significant coronary disease, or death before a decision about revascularization could be made. MEASUREMENTS: Survival, quality of life, and functional status at least 1 year after discharge. RESULTS: After catheterization, 41 patients had angioplasty, 18 had coronary artery bypass surgery, and 34 did not have revascularization. Among the patients alive at discharge, those who had revascularization had a high likelihood of achieving a good or excellent quality of life (angioplasty, 86% [31 of 36]; surgery, 89% [16 of 18]; medical therapy, 44% [11 of 25]) and of being able to care for themselves (angioplasty, 89% [32 of 36], surgery, 89% [16 of 18], medical therapy, 52% [13 of 25]). Mortality rates at 1 year were 24% (95% CI, 15% to 47%) for the angioplasty group, 6% (CI, 0% to 27%) for the surgery group, and 44% (CI, 27% to 62%) for the medical therapy group. In a Cox proportional hazards model that adjusted for clinical, demographic, hemodynamic, and anatomic differences between the groups, the performance of coronary revascularization was associated with increased survival (hazard ratio, 0.42; CI, 0.18 to 0.98). CONCLUSIONS: A small percentage of very elderly patients with complicated acute myocardial infarctions, selected by their physicians for invasive cardiovascular procedures, can tolerate these procedures, avoid serious complications, return to independent living, and have excellent probability of survival. Although our results suggest that coronary revascularization may have benefited these patients, the study design did not permit definite conclusions, and future studies are needed to resolve this important question.  相似文献   
1000.
The purpose of this study was to determine the functional outcome of a surgical technique for the repair of injuries of the ulnar collateral ligament of the thumb. A 14-point questionnaire was developed to determine functional outcome after surgical repair of acute ulnar collateral ligament rupture. Early ulnar collateral ligament repair was performed on 58 patients with grade III sprains (complete rupture) of the ligament using a new technique that employs a suture anchor for fixation. Forty-five patients were interviewed at a minimum postoperative interval of 12 months and were included in this study. Forty-four patients (98%) believed they had a stable repair, were satisfied with their surgery, and would have it again if necessary. Forty-four patients (98%) were not hindered in their day-to-day activities and had a functional range of motion. Mild discomfort was felt by eight of our patients (17%), but only three patients (7%) had pain with activities. The average time to return to skiing was 1.7 days. The use of a suture anchor provided a strong and stable repair if the surgery was performed early.  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