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   8479篇
  免费   178篇
各国政治   445篇
工人农民   443篇
世界政治   449篇
外交国际关系   293篇
法律   5449篇
中国政治   48篇
政治理论   1477篇
综合类   53篇
  2020年   72篇
  2019年   87篇
  2018年   196篇
  2017年   153篇
  2016年   234篇
  2015年   125篇
  2014年   141篇
  2013年   773篇
  2012年   261篇
  2011年   231篇
  2010年   155篇
  2009年   164篇
  2008年   186篇
  2007年   195篇
  2006年   202篇
  2005年   528篇
  2004年   242篇
  2003年   183篇
  2002年   140篇
  2001年   287篇
  2000年   233篇
  1999年   233篇
  1998年   96篇
  1997年   80篇
  1996年   73篇
  1995年   65篇
  1994年   74篇
  1993年   67篇
  1992年   142篇
  1991年   179篇
  1990年   173篇
  1989年   173篇
  1988年   171篇
  1987年   189篇
  1986年   186篇
  1985年   162篇
  1984年   144篇
  1983年   131篇
  1982年   83篇
  1981年   92篇
  1980年   71篇
  1979年   136篇
  1978年   94篇
  1977年   77篇
  1975年   91篇
  1974年   107篇
  1973年   94篇
  1972年   71篇
  1971年   74篇
  1970年   57篇
排序方式: 共有8657条查询结果,搜索用时 15 毫秒
261.
The U.S. electric power sector has experienced a substantial shift of the generation mix since the turn of the century, moving from heavy reliance on coal‐powered generation to one drawing more from natural gas and, more recently, renewables. This transition has been forged by a mix of macroeconomic factors (recession and recovery); technological breakthroughs (horizontal drilling coupled with hydraulic fracturing; improvements in natural gas plant efficiency); clean energy policies at federal, state, and local levels of government; and private sector demands for carbon‐free energy sources. These factors have combined to reduce carbon emissions from electric power generation substantially this century. In this article we examine the extent of this transition, its causes, as well as the distinct American institutional factors steering it, including energy and environmental federalism, electoral politics, and the political economy of clean energy policy enactment and resistance.  相似文献   
262.
The current study examined the process by which attachment to parents influences satisfaction with and ease in forming friendships at college. One hundred seventy-two female college freshmen completed a measure of parental attachment security the summer before their first semester of college (July 2006) and measures to assess satisfaction with and ease in forming close relationships at the end of their first semester (December 2006). Students ranged in age from 18 to 20 years (M = 18.09, SD = 0.33) and were diverse in their racial makeup (30% racial minority). Consistent with predictions derived from attachment theory, secure attachment to parents was positively associated with ease in forming friendships among racial minority and white participants and satisfaction with friendships among minority participants. Moreover, indirect effects of parental attachment security on relationship outcomes through social anxiety were significant for minority participants but not for white participants. Findings may be useful in the development of retention programs targeted at incoming university freshmen, particularly minority students.  相似文献   
263.
Research on the mechanisms by which interparental conflict (IPC) affects child depression suggests that both parenting and children’s conflict appraisals play important roles, but few studies have explored the role of general cognitive style or included both parenting and cognitions in the same design. Moreover, the effects of IPC on minority children are not well understood. In this longitudinal study, parenting was examined as a mediator of the relation between increasing IPC and change in depression. General cognitive style was included as a moderator. The combined influence of parenting and cognitions was also explored. A racially and ethnically diverse sample of 88 fifth and sixth graders from two urban schools reported their cognitive style, depressive symptoms, and perceptions of conflict and parenting at two time points separated by one year. Parental warmth/rejection mediated the relation between IPC and depression, and general cognitive style acted as a moderator. Parenting, cognitive style, and IPC did not significantly interact to predict change in depression over time. Findings indicate that both parenting and children’s general cognitive style play a role in understanding the impact of increasing IPC on children’s well-being.  相似文献   
264.
265.
Children of immigrants who do translations and who interpret for others using their heritage language and English are known as language brokers. Although prior research suggests that children of immigrants’ perceptions of the language brokering experience vary greatly—from feeling a sense of efficacy to feeling a sense of burden—what remains unanswered in the literature is identification of the antecedents and processes that help to explain the varying psychological experience of language brokers. Using data from a two-wave prospective longitudinal study of 256 Chinese American adolescents, the present study tested potential mechanisms that may be responsible for adolescents’ perceptions of the language brokering experience as a sense or burden or sense of efficacy. The results demonstrate that adolescents’ Chinese orientation sets in motion a family process that is linked to variations in the perceptions of adolescents’ language brokering experience. Adolescents who are more Chinese oriented have a stronger sense of familial obligation, and these adolescents are more likely to perceive that they matter to their parents. Adolescents’ perceived sense of mattering to parents, in turn, is associated positively with a sense efficacy, and negatively with a sense of burden as language brokers. Those adolescents who are less Chinese oriented have a weaker sense of familial obligation, and these adolescents are more likely to feel a sense of alienation from their parents. Adolescents’ sense of perceived alienation from parents, in turn, is associated with a sense of burden as language brokers. Implications for developing interventions for children who act as language brokers for their parents are discussed.
Su Yeong Kim (Corresponding author)Email: Email:
  相似文献   
266.
Considerable research has focused on the reliability and validity of informant reports of family behavior, especially maternal reports of adolescent problem behavior. None of these studies, however, has based their orientation on a theoretical model of interpersonal perception. In this study we used the social relations model (SRM) to examine family members’ reports of each others’ externalizing and internalizing problem behavior. Two parents and two adolescents in 69 families rated each others’ behavior within a round-robin design. SRM analysis showed that within-family perceptions of externalizing and internalizing behaviors are consistently due to three sources of variance; perceiver, target, and family effects. A family/contextual effect on informant reports of problem behavior has not been previously reported.  相似文献   
267.
In many EU countries, the so-called social investment perspective has provided new arguments for active welfare state policies. The social investment perspective is characterized by emphasizing the role of the state to increase participation in employment by investing in the working capacity of the population—particularly women—through activation programmes and social policies. In this article we depart from recent debates surrounding this perspective to explore changes in Norwegian work and welfare policies, and the role of gender equality in these changes. In Norway, both female employment and fertility levels are high, but women still have a looser connection to the labour market compared to men, for example due to the large proportion in part-time positions, which makes changes in work and welfare policies an interesting case for exploring the relevance of the social investment perspective in this context. The empirical analysis suggests that ideas of social investment indeed have permeated recent changes in Norwegian work and welfare policies. However, questions of gender equality are not addressed in the documents introducing these changes, except when the problem at hand is the employment rate of migrant women—who are the main recipients of activation policies. In conclusion, we claim that social investment is a relevant lens for analysing changes in Norwegian work and welfare policies, but that a dual-tracked vision of gender equality is emerging, making migrant women the significant target of social investment.  相似文献   
268.
Peer relationships, particularly friendships, have been theorized to contribute to how children and adolescents think about social and moral issues. The current study examined how young adolescent best friends (191 dyads; 53.4 % female) reason together about multifaceted social dilemmas and how their reasoning is related to friendship quality. Mutually-recognized friendship dyads were videotaped discussing dilemmas entailing moral, social-conventional and prudential/pragmatic issues. Both dyad members completed a self-report measure of friendship quality. Dyadic data analyses guided by the Actor-Partner Interdependence Model indicated that adolescent and friend reports of friendship qualities were related to the forms of reasoning used during discussion. Friends who both reported that they could resolve conflicts in a constructive way were more likely to use moral reasoning than friends who reported that their conflict resolution was poor or disagreed on the quality of their conflict resolution. The findings provide evidence for the important role that friendship interaction may play in adolescents’ social and moral development.  相似文献   
269.
270.
Previous studies have indicated homophily in depressive symptoms among adolescent friends, resulting from both peer selection and socialization processes. However, developmental differences and the role of school transitions in these processes have not been elucidated. A sample of 367 (51% female) adolescents was followed from 6th to 11th grade to investigate prospective relationships between adolescents’ and their friends’ depressive symptoms in middle school and in high school. Results revealed that students selected friends with similar levels of depressive symptoms after each school transition. Additionally, friends appeared to socialize adolescents to become more similar in depressive affect in late middle school years. These findings suggest normative selection effects after school transitions, followed by socialization effects in middle school, but not high school.  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