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   8263篇
  免费   3篇
各国政治   200篇
工人农民   1072篇
世界政治   223篇
外交国际关系   279篇
法律   4643篇
政治理论   1849篇
  2023年   3篇
  2021年   1篇
  2020年   4篇
  2019年   4篇
  2018年   1270篇
  2017年   1198篇
  2016年   1011篇
  2015年   58篇
  2014年   14篇
  2013年   17篇
  2012年   187篇
  2011年   913篇
  2010年   1013篇
  2009年   577篇
  2008年   730篇
  2007年   691篇
  2006年   17篇
  2005年   72篇
  2004年   174篇
  2003年   142篇
  2002年   32篇
  2001年   1篇
  2000年   4篇
  1998年   9篇
  1997年   11篇
  1996年   19篇
  1995年   28篇
  1994年   22篇
  1993年   1篇
  1984年   9篇
  1983年   8篇
  1982年   5篇
  1979年   5篇
  1978年   7篇
  1977年   9篇
排序方式: 共有8266条查询结果,搜索用时 15 毫秒
121.
122.
The ability of the minority party to influence legislation in Congress is debated. Most bills are passed with large bipartisan majorities, yet the House, where most legislation is developed, is seen as a majority-party-dominated institution. I develop a theory of House minority-party influence at the committee markup stage as a result of the Senate’s institutional rules. An original data set of congressional committee votes shows that minority-party support in House committees predicts House and Senate passage. During unified party control of the chambers, an increase in Senate majority-party seats results in lower minority-party support for the legislation in the House committee, while during divided party control of Congress, the House majority passes more extreme bills as the chambers polarize. Even in the majority-party-dominated House, the minority’s preferences are incorporated into legislation, and the Senate’s institutional rules moderate bills to a significant degree.  相似文献   
123.
This study developed a composite machine learning algorithm for attribution of materials of forensic interest (like ammonium nitrate) to original sources. k-nearest neighbor and random forest models were used for source elimination and classification, respectively, in a two-step, composite algorithm based on particle color, size/shape, and trace element concentration features. Novel approaches for simulation to supplement within-source reference features based on empirically measured multi-lot analyses, an improved hold-one-lot-out method for cross-validation, an assessment of the likelihood of the presence of a reference sample, fusion of the source probabilities from the respective classification models, and the calculation of metrics for assessing ensemble sourcing performance are described. Excellent sourcing predictions were obtained; the sourcing algorithm identified the correct source as the top choice 89% of the time, and the correct source was identified to be an average of 2.7 times more likely than the most likely incorrect source.  相似文献   
124.
Correspondence in value orientation between parents and their offspring may be due to actual transmission processes between generations, but it may also be due to influences from the general value context in society that are common to parents and their offspring. This common value context is referred to as Zeitgeist. The present study deals with one family relationship value (i.e., parents’ and adolescents’ obligations toward the family). Participants were 1,252 immigrant and 726 national adolescent–parent dyads from 10 Western countries. There were significant relationships between the value placed on family obligations among parents and offspring, and these were independent of gender. Zeitgeist effects, both intergenerational and intragenerational, were found. The strength of these Zeitgeist effects depended on the basis for defining Zeitgeist, either a person’s own ethnic group or the wider community including both nationals and immigrants. For explaining national adolescents’ acceptance of their family obligations, both the ethnic and the national Zeitgeist played a role, whereas in the immigrant groups only the ethnic Zeitgeist played a significant role. In short, in an immigration context it makes sense to distinguish the influence of a person’s own ethnic group from the influence of the wider community, including other ethnic groups. Explanations are suggested and implications are discussed.
Paul VedderEmail:
  相似文献   
125.
Focusing on identity development explorations enables a greater understanding of contexts that affect immigrant adolescents. Utilizing thematic and grounded narrative analysis of 46 journal writings, during a one-month period, from first and second generation Vietnamese adolescents ranging in age from 15 to 18 (26 residents of a culturally and politically active ethnic enclave in Southern California; 20 adolescents living outside the enclave), this study establishes ways in which a focus on social context and exploration processes illuminates the complexity of immigrant adolescents’ identity formation. The two groups shared many similarities, including precipitants to exploration and steps undertaken to explore identity. However, two factors—social and cultural influences and emotional reactions—revealed interesting contrasts distinguishing enclave from non-enclave dwelling Vietnamese adolescents. Data also suggested that immigrant adolescents strive to integrate different domains of identity (ethnicity, gender, career) both with one another and with the historical, social, and cultural contexts they occupy.
Jaan ValsinerEmail:
  相似文献   
126.
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   
127.
This study examined the association between cigarette smoking and dieting behaviors and trends in that association among US adolescents in grades 9–12 between 1999 and 2007. Youth Risk Behavior Survey datasets were analyzed using the multivariable logistic regression method. The sample size of each survey year ranged from 13,554 to 15,273 with girls representing 49–51% of the sample (N = 71,854). About 62% of the entire study participants were whites and 14% were blacks. Prevalence estimates of current smoking and corresponding 95% confidence intervals were computed across four comparison groups formed by gender and body weight. Extreme dieting was an independent predictor of smoking. Extreme dieters showed a higher variability of smoking behavior than their peers. The magnitude of the association between smoking and extreme dieting became smaller in recent years among adolescents but remained unchanged among non-overweight girls over that same time period. When adolescent smoking behavior is examined, the intensity of dieting behavior should be considered within its association with other co-occurring unhealthy behaviors.  相似文献   
128.
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   
129.
The main purpose of this study was to examine the extent to which middle and late adolescents’ depressive symptoms predict their later school burnout and, in turn, the extent to which school burnout predicts depressive symptoms. Drawing on data gathered at ages 15–19 in two-three-wave longitudinal studies, we investigated cross-lagged paths between school burnout and depressive symptoms. In Study 1 the participants were 15-year-old adolescents (Time 1: N = 611, Time 2: N = 614, Time 3: N = 725) who completed the School Burnout Inventory and depressive symptoms twice during their final term of comprehensive school and once after the transition to upper secondary high school or vocational school. In Study 2 the participants were 17-year-old adolescents whose school burnout and depressive symptoms were measured three times annually (Time 1: N = 474, Time 2: N = 412, Time 3: N = 414) during their 3 years of secondary education. Results of both studies revealed moderate stability for both school burnout and depressive symptoms. They also showed that school burnout more strongly predicted subsequent depressive symptoms later on than vice versa. Lastly, they revealed cumulative cycles between school burnout and depressive symptoms.  相似文献   
130.
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