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   10150篇
  免费   52篇
  国内免费   1篇
电工技术   85篇
综合类   1篇
化学工业   426篇
金属工艺   20篇
机械仪表   37篇
建筑科学   45篇
矿业工程   2篇
能源动力   26篇
轻工业   110篇
水利工程   9篇
石油天然气   8篇
无线电   328篇
一般工业技术   393篇
冶金工业   8122篇
原子能技术   29篇
自动化技术   562篇
  2021年   26篇
  2020年   17篇
  2019年   27篇
  2018年   26篇
  2017年   31篇
  2016年   17篇
  2015年   26篇
  2014年   22篇
  2013年   132篇
  2012年   63篇
  2011年   79篇
  2010年   86篇
  2009年   86篇
  2008年   94篇
  2007年   74篇
  2006年   81篇
  2005年   71篇
  2004年   54篇
  2003年   75篇
  2002年   76篇
  2001年   67篇
  2000年   55篇
  1999年   283篇
  1998年   2434篇
  1997年   1395篇
  1996年   919篇
  1995年   520篇
  1994年   461篇
  1993年   516篇
  1992年   106篇
  1991年   147篇
  1990年   144篇
  1989年   138篇
  1988年   140篇
  1987年   132篇
  1986年   135篇
  1985年   135篇
  1984年   43篇
  1983年   61篇
  1982年   79篇
  1981年   91篇
  1980年   75篇
  1979年   29篇
  1978年   55篇
  1977年   214篇
  1976年   420篇
  1975年   37篇
  1974年   30篇
  1972年   20篇
  1970年   17篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Examined psychosocial variables by comparing 10 13–17 yr old adolescents (and their mothers) who had refused cancer treatment with a group of 10 consenting adolescents who were matched on age and demographic and illness variables. Adolescents completed the State-Trait Anxiety Inventory for Children and measures of family characteristics, locus of control, religion, hopelessness, impact of event, and satisfaction with physician. Mothers completed the State-Trait Anxiety Inventory and measures of coping and religion. Adolescent refusers scored lower on state anxiety and subjective distress but scored higher on trait anxiety, religiosity, and external locus of control. Their mothers also scored higher than did the consenting-group mothers on religiosity and trait anxiety. It is suggested that refusers are prone to anxiety and cope with their present distress by maintaining the belief that their lives are determined by fate or religious convictions. An intervention approach that fosters mastery over the cancer experience is advocated. (8 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
72.
73.
74.
A systematic study of wall effects on the shear viscosity of short glass fiber-filled polypropylene and polystyrene is presented. The dependence of these effects on capillary radius, shear rate, temperature, and polymer matrix is examined. The “true” viscosity curves of these materials (free from wall effects) can be obtained by an extrapolation procedure. Breakage of glass fibers in the high shear-rate processes of extrusion and injection molding lead to an appreciable reduction of the viscosity of these materials and is probably the more important effect to take into account in these processes.  相似文献   
75.
76.
77.
78.
79.
We were concerned with the effects of item repetition, list length, and class of item on free recall in elderly as compared with young adults. In Experiment 1, samples of young and elderly adults recalled a list of 27 words and a list of 27 action events (minitasks performed by the subjects). Some items were presented once and some twice. Although the younger subjects showed better recall on both types of lists, the older sample benefited from item repetition as much as did the younger sample. This finding was replicated in Experiment 2. A second finding in Experiment 2 was a significant aging effect in the recall of long but not of short lists of both words and action events. The absence of an Age?×?Repetition Effect interaction was ascribed to the strength nature of the repetition manipulation. The age effects in the recall of the long lists were attributed to possible deficits in retrieval proficiency. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
80.
The available surgical and non-surgical therapy options for treatment of gallstone disease are presented. Conventional cholecystectomy is regarded as standard therapy of symptomatic cholecystolithiasis. Other modes of therapy may be indicated under certain circumstances, depending on the results of imaging procedures. In this context conventional X-ray examination, oral and intravenous cholecystography, sonography, computed tomography, endoscopic retrograde cholangiography/cholecystography, and magnetic resonance imaging are discussed and their influence on therapeutic decisions is explained.  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