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   32372篇
  免费   988篇
  国内免费   13篇
  2020年   296篇
  2019年   310篇
  2018年   491篇
  2017年   507篇
  2016年   647篇
  2015年   468篇
  2014年   433篇
  2013年   2158篇
  2012年   993篇
  2011年   1007篇
  2010年   494篇
  2009年   502篇
  2008年   750篇
  2007年   696篇
  2006年   626篇
  2005年   1881篇
  2004年   1171篇
  2003年   970篇
  2002年   668篇
  2001年   741篇
  2000年   716篇
  1999年   521篇
  1998年   276篇
  1997年   267篇
  1992年   515篇
  1991年   499篇
  1990年   522篇
  1989年   507篇
  1988年   445篇
  1987年   464篇
  1986年   498篇
  1985年   518篇
  1984年   440篇
  1983年   410篇
  1982年   303篇
  1981年   332篇
  1979年   476篇
  1978年   340篇
  1977年   301篇
  1976年   297篇
  1975年   439篇
  1974年   498篇
  1973年   504篇
  1972年   432篇
  1971年   414篇
  1970年   391篇
  1969年   416篇
  1968年   509篇
  1967年   491篇
  1966年   468篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
Wistar rats of three age groups were tested in an automated tunnel-maze system of variable geometry to investigate whether changes in spontaneous locomotor activity and in learning and memory develop differentially or in a correlated fashion as a function of age. Senescent (30 months) as well as mature-adult (17 months) rats showed an age-correlated decline of locomotor activity as compared to the mature-young (5 months) group. Both working-memory (measured as within-trial arm discrimination performance) and reference-memory (measured as avoidance of "blind alley" visits) were severely affected in the senescent group, whereas the middle-aged animals suffered only from a working-memory deficit. The findings provide evidence that locomotor deficits do not necessarily interfere in the assessment of age-related changes in cognitive performance. Furthermore the results support the hypothesis that working and reference memory have different underlying physiological correlates and that these neuronal systems are differentially affected by the aging process.  相似文献   
112.
113.
In a study of air traffic controllers, religious differences are found in the way Type A behavior is associated with several health status indicators. Associations between the Jenkins Activity Survey (JAS) and physical illness incidence, health-promotive behavior, diastolic and systolic blood pressure, subjective distress and impulse control problems, and alcohol consumption are examined by religious attendance, religious affiliation, and change in affiliation. Findings confirm that Type A does not vary significantly by religion. However, there are several significant findings between Type A and various health indicators. Type A is associated with illness incidence, overall and more strongly in several religion, subgroups. Type A and alcohol consumption are related positively in Protestants and converts, and negatively in churchgoing Catholics. Type A is related to impulse control problems in churchgoing Protestants and to subjective distress in churchgoing Catholics. Finally, in individuals with weak or no religious ties, Type A is associated with lower blood pressure. This last finding suggests that in some people (for example, the irreligious or unchurched), the coronary-prone behavior pattern may have cardiovascular effects which are salutary in at least one respect.The authors wish to thank Dr. Kyriakos S. Markides and Laura A. Ray for their assistance with this study. Address requests for reprints to Dr. Levin at the Institute of Gerontology, 300 North Ingalls, Ann Arbor, MI 48109.  相似文献   
114.
115.
This essay reports a program of research as the occupational and personal stress experienced by contemporary American clergy. Three studies are reported. In the first survey a group of largely Roman Catholic religious reported less stress than the general population. In a replication of this investigation on over 510 Protestant clergy this impression of less experienced stress and greater personal resources was confirmed. In the most recent study of clergy in Southern California, a mixed picture was observed. Although the impression of less overall stress was confirmed, great differences in layclery role expectations were observed.He is the coauthorof Clergy Malpractice: How to Care Carefully (Westminster Press, 1986) and is engaged in a variety of ministerial studies.Paper presented at the meeting of the International Council of Psychologists, Mexico City, September, 1984.  相似文献   
116.
117.
118.
The Rosenberg Self-esteem Scale was administered to 550 14- and 16-yr.-old (+/- 6 mo.) girls. Self-esteem scores were categorized by weight and weight by height. Scores on the Quetelet Index for obesity were correlated with self-esteem scores. Mean self-esteem of the low- and middle-weight by height group was significantly higher than the mean of the high-weight by height group. In analyzing weight alone, the self-esteem of the middle-weight group was significantly higher than the self-esteem of the high-weight group. The correlation of the obesity index and self-esteem indicated that as weight increased self-esteem decreased.  相似文献   
119.
Observations on three children with neurolisteriosis (one case of meningitis, two cases of meningoencephalitis, each Serovar 4 b), show that even after the neonatal period, listeriosis must not be ignored in the process of diagnosis and therapy. It is the bacteriological examination of the cerebrospinal fluid, together with the blood culture, and not clinical symptoms and serology that guarantee a timely diagnosis and therapy (ampicillin and gentamicin).  相似文献   
120.
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