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   3782篇
  免费   122篇
  国内免费   2篇
  3906篇
  2021年   24篇
  2020年   42篇
  2019年   75篇
  2018年   101篇
  2017年   82篇
  2016年   99篇
  2015年   76篇
  2014年   73篇
  2013年   460篇
  2012年   146篇
  2011年   142篇
  2010年   110篇
  2009年   90篇
  2008年   126篇
  2007年   149篇
  2006年   138篇
  2005年   142篇
  2004年   140篇
  2003年   126篇
  2002年   118篇
  2001年   60篇
  2000年   48篇
  1999年   58篇
  1998年   64篇
  1997年   46篇
  1996年   69篇
  1995年   60篇
  1994年   62篇
  1993年   56篇
  1992年   58篇
  1991年   43篇
  1990年   46篇
  1989年   48篇
  1988年   42篇
  1987年   43篇
  1986年   37篇
  1985年   64篇
  1984年   46篇
  1983年   51篇
  1982年   52篇
  1981年   36篇
  1980年   46篇
  1979年   32篇
  1978年   35篇
  1977年   27篇
  1976年   28篇
  1975年   25篇
  1974年   32篇
  1973年   22篇
  1971年   14篇
排序方式: 共有3906条查询结果,搜索用时 15 毫秒
911.
912.
913.
Fathering activities of 16 fathers of firstborns were surveyed via questionnaire to assess their involvement in physical caretaking, affective interaction and support of mother through participation in household tasks. Results indicated that student fathers who had previous infant care experience, whose infants were unplanned and whose wives were either employed or attending school spent the most time interacting with their infants. Other variables explored which had little effect on father's interaction time included: formal education, attendance at prenatal clases, infant's sex and method of feeding, family isolation. Fathers spent more time in affective interaction than in physical caretaking. Time spent by fathers in affective interaction was nearly equal to that of mothers, while time spent in physical caretaking was much greater for mothers.  相似文献   
914.
In experiment 1, individually housed rats subjected to short-term food restriction displayed more territorial aggression toward conspecific intruders than controls maintained on a free-feeding diet. In experiment 2, small groups of three adult male rats had access to either a standard laboratory diet or the standard diet plus sucrose. Groups with the sucrose supplement were significantly less aggressive toward intruders than controls. Sucrose availability did not produce appreciable gains in body weight but it did reliably decrease within-colony weight variation. The results suggest the existence of an effective dietary mechanism that enables a social species such as Rattus norvegicus to tolerate each other in dense feeding aggregations when food is abundant. Conversely, when food is limited, social intolerance increases and serves to limit the development of large feeding groups.  相似文献   
915.
We aimed to assess which comorbid problems (oppositional defiant behaviors, anxiety, autistic traits, motor coordination problems, and reading problems) were most associated with Attention-Deficit/Hyperactivity Disorder (ADHD); to determine whether these comorbid problems shared executive and motor problems on an endophenotype level with ADHD; and to determine whether executive functioning (EF)—and motor-endophenotypes supported the hypothesis that ADHD with comorbid problems is a qualitatively different phenotype than ADHD without comorbid problems. An EF—and a motor-endophenotype were formed based on nine neuropsychological tasks administered to 816 children from ADHD—and control-families. Additional data on comorbid problems were gathered using questionnaires. Results indicated that oppositional defiant behaviors appeared the most important comorbid problems of ADHD, followed by autistic traits, and than followed by motor coordination problems, anxiety, and reading problems. Both the EF—and motor-endophenotype were correlated and cross-correlated in siblings to autistic traits, motor coordination problems and reading problems, suggesting ADHD and these comorbid problems may possibly share familial/genetic EF and motor deficits. No such results were found for oppositional defiant behaviors and anxiety. ADHD in co-occurrence with comorbid problems may not be best seen as a distinct subtype of ADHD, but further research is warranted. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
916.
917.
918.
Media psychologists have long puzzled over how individuals can experience enjoyment from entertainment such as tragedies that often elicit profound feelings of sadness. The present research examines the idea that a focus on “meaningful” entertainment and affective responses identified as “elevation” may provide a framework for understanding many examples of sad or dramatic entertainment. The results of this study suggest that many types of meaningful cinematic entertainment feature portrayals of moral virtues (e.g., altruism). These portrayals, in turn, elicit feelings of elevation (e.g., inspiration) that are signified in terms of mixed affect and unique physical responses (e.g., lump in throat). Ultimately, elevation also gives rise to motivations to embody moral virtues, such as being a better person or helping others.  相似文献   
919.
This study examines data from questionnaires to establish the prevalence and correlates of women's binge drinking, defined as four or more drinks per episode, at women's colleges ( n = 508) and at coeducational colleges ( n = 9,624). Results showed that women at women's colleges binged less frequently, had fewer alcohol-related problems, experienced fewer negative effects of others' drinking, and were less likely to drink and drive. The correlates of binge drinking were similar for the two groups of women. The differences appear to be related not to the quantity or amount of socializing but to its quality. The absence of fraternities and coeducational dormitories, the reduced likelihood of a party-centered lifestyle, and self-selection factors at women's colleges all may contribute to a healthier environment for women. Interventions designed to lower the risk of college binge drinking should further explore the peer-group contexts in which problem drinking is reduced.  相似文献   
920.
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