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   29629篇
  免费   436篇
  国内免费   4篇
  2023年   75篇
  2022年   67篇
  2021年   135篇
  2020年   211篇
  2019年   169篇
  2018年   3662篇
  2017年   2993篇
  2016年   2520篇
  2015年   425篇
  2014年   352篇
  2013年   1052篇
  2012年   1063篇
  2011年   2792篇
  2010年   2769篇
  2009年   1717篇
  2008年   2046篇
  2007年   2518篇
  2006年   359篇
  2005年   547篇
  2004年   486篇
  2003年   392篇
  2002年   358篇
  2001年   209篇
  2000年   186篇
  1999年   174篇
  1998年   139篇
  1997年   138篇
  1996年   108篇
  1995年   93篇
  1994年   88篇
  1993年   95篇
  1992年   108篇
  1991年   97篇
  1990年   105篇
  1989年   79篇
  1988年   65篇
  1987年   85篇
  1986年   84篇
  1985年   91篇
  1984年   89篇
  1983年   87篇
  1982年   67篇
  1981年   87篇
  1980年   77篇
  1979年   89篇
  1978年   78篇
  1977年   79篇
  1976年   79篇
  1975年   74篇
  1974年   83篇
排序方式: 共有10000条查询结果,搜索用时 14 毫秒
1.
2.
3.
4.
Range of electric vehicles (EVs) has long been considered a major barrier in acceptance of electric mobility. We examined the nature of how range is experienced in an EV and whether variables from other adaptation contexts, notably stress, have explanatory power for inter‐individual differences in what we term comfortable range. Forty EVs were leased to a sample of users for a 6‐month field study. Qualitative and quantitative analyses of range experiences were performed, including regression analyses to examine the role of stress‐buffering personality traits and coping skills in comfortable range. Users appraised range as a resource to which they could successfully adapt and that satisfied most of their daily mobility needs. However, indicators were found that suggested suboptimal range utilisation. Stress‐buffering personality traits (control beliefs, ambiguity tolerance) and coping skills (subjective range competence, daily range practice) were found to play a substantial role in comfortable range. Hence, it may be possible to overcome perceived range barriers with the assistance of psychological interventions such as information, training, and interface design. Providing drivers with a reliable usable range may be more important than enhancing maximal range in an electric mobility system.  相似文献   
5.
6.
7.
OBJECTIVE: To test a theoretical model of how ethnic pride and self-control are related to risk and protective factors. DESIGN: A community sample of 670 African American youth (mean age = 11.2 years) were interviewed in households. MAIN OUTCOME MEASURES: Measures of cigarette smoking, alcohol use, and sexual behavior (lifetime to past month). RESULTS: Structural modeling analyses indicated parenting was related to self-control and self-esteem, and racial socialization was related to ethnic pride. Self-control and self-esteem variables were related to levels of deviance-prone attitudes and to perceptions of engagers in, or abstainers from, substance use and sexual behavior. The proximal factors (behavioral willingness, resistance efficacy, and peer behavior) had substantial relations to the criterion variables. Participant gender and parental education also had several paths in the model. Results were generally similar for the 2 outcome behaviors. CONCLUSIONS: In this population, self-esteem and self-control are related to parenting approaches and have pathways to attitudes and social perceptions that are significant factors for predisposing to, or protecting against, early involvement in substance use and sexual behavior.  相似文献   
8.
9.
10.
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