全文获取类型
收费全文 | 22487篇 |
免费 | 679篇 |
专业分类
各国政治 | 1004篇 |
工人农民 | 838篇 |
世界政治 | 1883篇 |
外交国际关系 | 795篇 |
法律 | 13314篇 |
中国共产党 | 2篇 |
中国政治 | 109篇 |
政治理论 | 4992篇 |
综合类 | 229篇 |
出版年
2020年 | 273篇 |
2019年 | 335篇 |
2018年 | 450篇 |
2017年 | 494篇 |
2016年 | 526篇 |
2015年 | 375篇 |
2014年 | 426篇 |
2013年 | 2299篇 |
2012年 | 523篇 |
2011年 | 564篇 |
2010年 | 468篇 |
2009年 | 511篇 |
2008年 | 571篇 |
2007年 | 589篇 |
2006年 | 596篇 |
2005年 | 512篇 |
2004年 | 512篇 |
2003年 | 529篇 |
2002年 | 505篇 |
2001年 | 813篇 |
2000年 | 744篇 |
1999年 | 617篇 |
1998年 | 363篇 |
1997年 | 319篇 |
1996年 | 260篇 |
1995年 | 269篇 |
1994年 | 307篇 |
1993年 | 286篇 |
1992年 | 427篇 |
1991年 | 482篇 |
1990年 | 424篇 |
1989年 | 455篇 |
1988年 | 415篇 |
1987年 | 455篇 |
1986年 | 452篇 |
1985年 | 448篇 |
1984年 | 400篇 |
1983年 | 429篇 |
1982年 | 338篇 |
1981年 | 315篇 |
1980年 | 250篇 |
1979年 | 321篇 |
1978年 | 229篇 |
1977年 | 191篇 |
1976年 | 188篇 |
1975年 | 168篇 |
1974年 | 193篇 |
1973年 | 177篇 |
1972年 | 151篇 |
1971年 | 134篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
901.
Willeke A. Manders Jan M. A. M. Janssens William L. Cook Johan H. L. Oud Eric E. J. De Bruyn Ron H. J. Scholte 《Journal of youth and adolescence》2009,38(10):1328-1338
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
902.
Roger J. R. Levesque 《Journal of youth and adolescence》2009,38(10):1281-1281
903.
Everyday interactions with same-racial/ethnic others may confer positive benefits for adolescents, but the meaning of these interactions are likely influenced by individual differences and larger structural contexts. This study examined the situation-level association between contact with same-ethnic others and anxiety symptoms among a diverse sample of 306 racial/ethnic minority adolescents (Mage = 14 years; 66 % female), based on (1) individual differences in ethnic identity centrality and (2) developmental histories of transitions in diversity between elementary, middle, and high school. The results indicated that at the level of the situation, when adolescents interacted with more same-ethnic others, they reported fewer anxiety symptoms. Further, for adolescents who had experienced a transition in school diversity, the positive benefits of contact with same-ethnic others was only conferred for those who felt that their ethnicity was very important to them. The importance of examining individual differences within larger developmental histories to understand the everyday experiences of ethnic minority adolescents are discussed. 相似文献
904.
Jean Marie McGloin Christopher J. Sullivan Kyle J. Thomas 《Journal of youth and adolescence》2014,43(9):1436-1452
This article focuses on the degree to which friends’ influence on substance use is conditioned by the consistency between their behavior and that of schoolmates (individuals enrolled in the same school, but not identified as friends), contributing to the literature on the complexity of interactive social influences during adolescence. Specifically, it hypothesizes that friends’ influence will diminish as their norms become less similar to that of schoolmates. The authors also propose that this conditioning relationship is related to the density of the friendship group. This study uses data from the National Longitudinal Survey of Adolescent Health (AddHealth) (n ~ 8,000, 55 % female) to examine the interactive relationship between friend and schoolmate influences on adolescent substance use (smoking and drinking). The sample contains students ranging from age 11 to 22 and is 60 % White. The findings demonstrate that, as the substance use of the friendship group becomes more dissimilar from schoolmates’ substance use, the friendship group’s influence on adolescent substance use diminishes. Further, the results demonstrate that this conditioning relationship does not emerge when the friendship group is highly dense. 相似文献
905.
Prior research has identified a vast number of correlates for delinquent behavior during adolescence, yet a considerable number of errors in prediction remain. These errors suggest that behavioral development among a portion of youths is not well understood, with some exhibiting resilience and others a heightened vulnerability to risks. Examining cases that do not confirm prediction outcomes provides an opportunity to achieve a greater understanding of the relationships between risk factors and delinquency, which can be used to improve theoretical explanations of behavior. This study explores the contribution of genetic and environmental factors to differences in individual responses to cumulative risk for delinquency among a sample of adolescent twins (N = 784 pairs, 49 % female) in the National Longitudinal Study of Adolescent Health. The results indicate that additive genetic and unique environmental factors significantly contribute to variation in responses to cumulative risk across 14 risk factors spanning individual, familial, and environmental domains. When analyzed separately, the majority of the difference between vulnerable youths and the overall population was attributed to genetic influences, while differences between resilient youths and the population were primarily attributed to environmental influences. The findings illustrate the importance of examining both genetic and environmental influences in order to enhance explanations of adolescent offending. 相似文献
906.
Understanding the prevalence and correlates of decisional autonomy within specific cultural contexts is necessary to fully
comprehend how family processes are embedded within culture. The goals of this study were to describe mothers’ and fathers’
decision-making with adolescents (M = 12.51 years, SD = 0.58; 51% female), including parent-unilateral, joint, and youth-unilateral decision-making, and to examine
the socio-cultural and family characteristics associated with these different types of decision-making in 246 Mexican-origin
families. Mothers reported more joint and youth-unilateral decision-making and less parent-unilateral decision-making than
did fathers. Fathers reported more youth-unilateral decision-making with sons than with daughters. Further, for mothers, more
traditional gender role attitudes and higher levels of mother-adolescent conflict were associated with more parent-unilateral
and less joint decision-making. In contrast, for fathers, lower levels of respect values were associated with more youth-unilateral
decision-making with sons, and higher levels of parent-adolescent warmth were associated with more youth-unilateral decision-making
with daughters. The importance of understanding the different correlates of mothers’ and fathers’ decision-making with sons
versus daughters is discussed. 相似文献
907.
This study examined the mediated and moderated effects of a universal family-focused preventive intervention, delivered during young adolescence, on internalizing symptoms assessed in young adulthood. Sixth grade students (N=446; 52% female; 98% White) and their families from 22 rural Midwestern school districts were randomly assigned to the experimental conditions in 1993. Self-report questionnaires were administered at seven time points (pre-test to young adulthood-age 21) to those receiving the Iowa Strengthening Families Program (ISFP) and to the control group. Results showed that growth factors of adolescent internalizing symptoms (grades 6-12) were predicted by ISFP condition and risk status (defined as early substance initiation). Moderation of the condition effect by risk status was found, with higher-risk adolescents benefitting more from the ISFP. Results also supported the hypothesis that the ISFP's effect on internalizing symptoms in young adulthood was mediated through growth factors of adolescents' internalizing symptoms; risk moderation, however, was only marginally significant in young adulthood. The relative reduction rate on clinical or subclinical levels of young adult internalizing symptoms was 28%, indicating that for every 100 young adults displaying clinical or subclinical levels of internalizing symptoms from school districts not offering an intervention, there could be as few as 72 displaying those levels of symptoms in school districts that offered middle school prevention programming. These findings highlight how the positive effects of family-focused universal interventions can extend to non-targeted outcomes and the related potential public-health impact of scaling up these interventions. 相似文献
908.
Kochel KP Miller CF Updegraff KA Ladd GW Kochenderfer-Ladd B 《Journal of youth and adolescence》2012,41(8):1022-1034
An accruing body of evidence supports associations between self-perceived gender typicality and peer relationship difficulties; however, researchers have yet to evaluate peers' perceptions of problem behaviors to gain insight into the social correlates of gender typicality. A short-term longitudinal study was conducted to evaluate associations between gender atypical problem behavior and subsequent peer relational difficulties for 2,076 fifth graders (M age= 10.27; 53% female). Peer nomination methodology was used to assess participants' classroom peer relationships, problem behaviors, and social-emotional characteristics. Findings showed that youth characterized by gender atypical, compared to gender typical, problem behavior (withdrawn boys/aggressive girls vs. withdrawn girls/aggressive boys, respectively) evidenced higher levels of subsequent peer difficulties; moreover, participation in a mutual friendship was associated with decreased risk for peer relationship maladjustment, particularly among youth characterized by gender atypical problem behavior. Results further revealed that, compared to friendless youth, friended youth earned higher prosocial and peer liking scores and, for withdrawn youth, lower emotional sensitivity scores. The present research contributes to our understanding of the potential short-term consequences of youth's gender atypical problem behavior. Findings underscore the need for supplemental conceptualizations of gender typicality as well as multifaceted interventions designed to promote the acceptance of gender nonnormativity, support the development of adaptive peer relationships, and reduce the occurrence of problem behaviors. 相似文献
909.
Roosa MW O'Donnell M Cham H Gonzales NA Zeiders KH Tein JY Knight GP Umaña-Taylor A 《Journal of youth and adolescence》2012,41(3):307-319
Mexican American youth are at greater risk of school failure than their peers. To identify factors that may contribute to
academic success in this population, this study examined the prospective relationships from 5th grade to 7th grade of family
(i.e., human capital [a parent with at least a high school education], residential stability, academically and occupationally
positive family role models, and family structure) and individual characteristics (i.e., externalizing symptoms, bilingualism,
gender, and immigrant status) to the academic performance of 749 Mexican American early adolescents (average age = 10.4 years
and 48.7% were girls in 5th grade) from economically and culturally diverse families as these youth made the transition to
junior high school. Results indicated that while controlling for prior academic performance, human capital and positive family
role models assessed when adolescents were in 5th grade positively related to academic performance in 7th grade. Further,
being a girl also was related to greater 7th grade academic success, whereas externalizing symptoms were negatively related
to 7th grade academic performance. No other variables in the model were significantly and prospectively related to 7th grade
academic performance. Implications for future research and interventions are discussed. 相似文献
910.
Ethnic Microaggressions and the Depressive and Somatic Symptoms of Latino and Asian American Adolescents 总被引:1,自引:0,他引:1
Huynh VW 《Journal of youth and adolescence》2012,41(7):831-846
Ethnic microaggressions are a form of everyday, interpersonal discrimination that are ambiguous and difficult to recognize as discrimination. This study examined the frequency and impact of microaggressions among Latino (n = 247) and Asian American (n = 113) adolescents (M (age) = 17.18, SD = .75; 57 % girls). Latino adolescents reported more frequent microaggressions that dismiss their realities of discrimination and microaggressions characterized by treatment as a second class citizen than Asian Americans, but similar levels of microaggressions that highlight differences or foreignness. There were no ethnic differences in the extent to which adolescents were bothered by microaggressions. Moreover, even supposedly innocuous forms of discrimination are associated with elevated levels of anxiety, anger, and stress, which may increase feelings of depression and sickness. Microaggressions should be recognized as subtle discrimination that send messages about group status and devaluation, and similar to overt discrimination, can evoke powerful emotional reactions and may affect mental health. 相似文献