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   8166篇
  免费   346篇
  国内免费   3篇
  8515篇
  2023年   42篇
  2021年   98篇
  2020年   153篇
  2019年   138篇
  2018年   206篇
  2017年   193篇
  2016年   241篇
  2015年   187篇
  2014年   211篇
  2013年   813篇
  2012年   394篇
  2011年   396篇
  2010年   271篇
  2009年   235篇
  2008年   351篇
  2007年   359篇
  2006年   306篇
  2005年   313篇
  2004年   305篇
  2003年   275篇
  2002年   294篇
  2001年   142篇
  2000年   92篇
  1999年   136篇
  1998年   115篇
  1997年   115篇
  1996年   96篇
  1995年   96篇
  1994年   85篇
  1993年   97篇
  1992年   99篇
  1991年   90篇
  1990年   73篇
  1989年   60篇
  1988年   56篇
  1987年   62篇
  1986年   68篇
  1985年   82篇
  1984年   74篇
  1983年   78篇
  1982年   68篇
  1981年   82篇
  1980年   73篇
  1979年   67篇
  1978年   76篇
  1977年   73篇
  1976年   66篇
  1975年   57篇
  1974年   64篇
  1966年   42篇
排序方式: 共有8515条查询结果,搜索用时 15 毫秒
841.
Predictions from smoking-specific versus contextual models of smoking onset were tested with data from a 4-wave sample with 1,364 adolescents. Predictor variables were derived from stress-coping theory, social influence theory, and problem-behavior theory. In addition to groups of abstainers and experimenters, cluster analysis of smoking data indicated 3 groups who showed onset either in 7th grade (early onset), 9th grade (intermediate onset), or 10th grade (late onset). Almost all study variables discriminated the smoking groups from the abstainers. The onset groups were discriminated by Group X Time interactions showing differential changes in predictors (increases in risk factors and declines in protective factors), which occurred just prior to onset. The results generally support a contextual model of the onset process.  相似文献   
842.
Thomas M. King 《Zygon》2007,42(3):779-792
Several recent Roman Catholics who were known for their devotion have left accounts of their troubled faith. I consider three of these: St. Therese of Lisieux, Mother Teresa of Calcutta, and Pierre Teilhard de Chardin. Then I tell of the troubled atheism of Jean‐Paul Sartre. Finally, I use texts of Sartre and Teilhard to understand the unsettled nature of belief.  相似文献   
843.
In work done at the German Criminological Research Institute of Lower Saxony (KFN) various methods have been used to investigate how specific inappropriate media usage patterns affect academic performance in children and adolescents. The findings are paralleled by current international research indicating a negative relationship between these two variables. Based on a cross‐sectional survey of 5,529 fourth grade students and a longitudinal panel study with 1,157 primary schoolchildren, a key finding can be demonstrated: the more time students spend on consuming media and the more violent its contents are, the worse are their marks at school, even when controlling for vital factors such as family, educational, or immigrant background. In particular, boys who gender‐specifically are better equipped with electronic media devices, who partially have extensive media usage times and who strongly prefer violent media content, are at the risk of showing poor school performance. In fact, a decrease in academic performance of boys can be observed in German school statistics. By presenting first results of a school‐based intervention programme, a promising approach to the reduction of detrimental effects of electronic media use on school performance is introduced.  相似文献   
844.
The Myers-Briggs Type Indicator was administered to a sample of 61 monozygotic twins reared apart (MZA), 49 dizygotic twins reared apart (DZA), and 92 spouses, who participated in the Minnesota Study of Twins Reared Apart (MISTRA) from 1979 to 1995. Twins' scores on the continuous scales were subjected to behavior genetic model-fitting procedures. Extraversion-Introversion and Thinking-Feeling yielded heritabilities of about .60, consisting largely of nonadditive genetic variance. Sensing-Intuition and Judgment-Perception yielded heritabilities of about .40, consisting largely of additive genetic variance. Spouse correlations for three of the four scales were near zero and not statistically significant; one spouse correlation (Sensing-Intuition) was modestly positive and statistically significant.  相似文献   
845.
Social support systems can have either a beneficial or adverse effect when a family faces stress. Hence, support perceived by family members is an important construct. We studied the psychometric properties of the Family Support Scale (FSS) with a sample of 244 low-income families of children in a Head Start program, and we conducted an exploratory factor analysis with the scale. We obtained a 5-factor solution for the FSS when assessing the family support of low-income families. The internal consistency and test-retest reliability were moderately high for the 5 proposed subscales. The factor structure obtained may prove more valid for Head Start families than structures from previous studies, although there is still a need for further psychometric study of the FSS.  相似文献   
846.
847.
An approach to modeling cognitive development with a generative connectionist algorithm is described and illustrated with a new model of conservation acquisition. Among the conservation phenomena captured with this model are acquisition, the problem size effect, the length bias effect, and the screening effect. The simulations suggest novel explanations for sudden jumps in conservation performance (based on new representations of conservation transformations) and for the problem size effect (based on an analog representation of number). The simulations support the correlation-learning explanation of length bias (that length correlates with number during number altering transformations). Some conservation phenomena that so far elude computational modeling attempts are also discussed along with their prospects for capture. Suggestions are made for theorizing about cognitive development as well as about conservation acquisition. A variety of classic puzzles about cognitive development are addressed in the light of this model and similar models of other aspects of cognitive development.  相似文献   
848.
849.
The Psychological Record - Previous studies have shown that conditional discrimination training procedures involving identity matching to complex samples can produce emergent arbitrary relations....  相似文献   
850.
This study examines longitudinally the development of vocational maturity and ethnic identity in a majority and a minority group of 641 students in the Province of Québec, Canada. Ethnic identity and four components of vocational maturity were assessed in four cohorts at three times of measurement. Results show clearly different developmental trends in both ethnic identity and in vocational maturity for majority and minority groups: The minority group showed a linear increase in ethnic identity over time, while the majority group showed a decrease starting with the second time of measurement; vocational maturity components showed a more complex pattern of changes but demonstrated that minority participants matured significantly earlier than those from the majority group. There was a positive relationship between ethnic identity and vocational maturity for both groups.  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