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   47840篇
  免费   1658篇
  国内免费   21篇
  2018年   602篇
  2017年   653篇
  2016年   712篇
  2015年   541篇
  2014年   641篇
  2013年   3447篇
  2012年   1156篇
  2011年   1225篇
  2010年   782篇
  2009年   774篇
  2008年   1164篇
  2007年   1055篇
  2006年   975篇
  2005年   899篇
  2004年   859篇
  2003年   876篇
  2002年   912篇
  2001年   1260篇
  2000年   1240篇
  1999年   928篇
  1998年   478篇
  1997年   484篇
  1996年   465篇
  1992年   901篇
  1991年   840篇
  1990年   862篇
  1989年   832篇
  1988年   787篇
  1987年   777篇
  1986年   840篇
  1985年   862篇
  1984年   733篇
  1983年   677篇
  1982年   496篇
  1981年   555篇
  1979年   799篇
  1978年   614篇
  1977年   542篇
  1976年   543篇
  1975年   704篇
  1974年   837篇
  1973年   885篇
  1972年   703篇
  1971年   718篇
  1970年   670篇
  1969年   709篇
  1968年   880篇
  1967年   810篇
  1966年   812篇
  1958年   467篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
961.
We evaluated the effects of adding a social support component to a worksite controlled smoking treatment program. Twenty-four participants were randomly assigned to either a controlled smoking or a controlled smoking plus partner support condition. Within a multiple baseline across behaviors design, smokers in both conditions made efforts to achieve sequential 50% reductions in: (a) nicotine content of brand smoked, (b) number of cigarettes smoked per day, and (c) percentage of each cigarette smoked. Self-monitoring records, laboratory analyses of spent cigarette butts, and carbon monoxide determinations indicated that both conditions were effective in producing significant reductions in each of the three target behaviors and in carbon monoxide levels. All participants who quit smoking during the program maintained their abstinence at a 6-month follow-up, and those who did not quit were smoking less at follow-up than they had at pretest on all dependent variables. However, few differences were observed between controlled smoking and controlled smoking plus partner support conditions either during treatment or at the 6-month follow-up. Results are discussed with regard to previous worksite studies, future directions for research on social support, and variables that may have mediated treatment outcome.  相似文献   
962.
963.
964.
In two longitudinal studies, infants were trained at 12 and 18 months to find an object hidden in one of two identical wells in a Plexiglas box. On the test trial, normal access was blocked and infants were either guided by their mother or allowed to move on their own to another opening on the opposite side. In Experiment 1 significantly more correct responding occurred after active movement than after passive at 12 months, with correct responding related to high visual tracking. In contrast, at 18 months correct search without tracking predominated among both movement conditions. A difference between the conditions in the position of the mother on the test trial was ruled out as a contributor to performance on the basis of data from Experiment 2. When opaque sides were inserted to prevent tracking in Experiment 3, active movement no longer facilitated correct search at 12 months, thus indicating that the tracking and not the active movement per se was the critical factor.  相似文献   
965.
966.
967.
Previous research has found mixed support for the possibility that locus of control moderates the effects of life stress on depression. Two methodological choices may have influenced previous findings: the use of a unidimensional rather than a multidimensional locus of control scale, and reliance on linear statistical methods using median splits. We attempted to correct these choices by using the Levenson IPC scale (1974) and multiple regression analyses in a female undergraduate population (N = 158). The results supported use of a multidimensional scale, since Stress, Internality, and Powerful Others were found to have main effects on depression whereas Chance interacted with life stress. The question of whether locus of control refers to responsibility for causing an event, i.e., self-blame, or belief in control over future events, i.e., coping behavior, was discussed.  相似文献   
968.
969.
Elementary school children between the ages of eight and thirteen were administered the Children's Nowicki/Strickland Locus of Control Scale annually for three years. As predicted, children's mean locus of control scores were found to be significantly different from one age group to the next (cross-sectional analysis) as well as from one year to the next (longitudinal analysis). Older children had significantly more internal scores than did younger children, and the same 97 children demonstrated significant increases in internal perceptions over each succeeding year. No significant sex differences were observed in this generally linear developmental trend. The study supports the hypothesis that increases in internal perceptions are associated with growing older. The data are explained using a confluent theoretical perspective drawing upon cognitive as well as behavioral theory.  相似文献   
970.
Figure drawings obtained from 758 white male medical students were scored using three different methods. Method I involved 16 different physical size measurements; Method II involved six separate sophistication of body concept ratings; and Method III involved 42 separate aspects of the drawings weighted in direct proportion to their relative frequency of occurrence in the sample studied (conventionality scoring). Separate factor analyses of the scores derived from each method revealed that Methods I and II each reflect only a single underlying factor, and that these factors are uncorrelated in the population studied. Method III yielded eight meaningful factors, each of which may be construed as an independent area of conventionality/deviancy. An overall conventionality/deviancy score was also derived. It is believed that these three methods of scoring capture most of the variance inherent in existing figure drawing scoring systems, but that use of all three is necessary for a comprehensive analysis.  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