全文获取类型
收费全文 | 22795篇 |
免费 | 618篇 |
专业分类
各国政治 | 901篇 |
工人农民 | 863篇 |
世界政治 | 1810篇 |
外交国际关系 | 772篇 |
法律 | 13995篇 |
中国共产党 | 2篇 |
中国政治 | 118篇 |
政治理论 | 4745篇 |
综合类 | 207篇 |
出版年
2020年 | 292篇 |
2019年 | 340篇 |
2018年 | 434篇 |
2017年 | 517篇 |
2016年 | 557篇 |
2015年 | 385篇 |
2014年 | 467篇 |
2013年 | 2209篇 |
2012年 | 549篇 |
2011年 | 587篇 |
2010年 | 474篇 |
2009年 | 510篇 |
2008年 | 590篇 |
2007年 | 638篇 |
2006年 | 618篇 |
2005年 | 535篇 |
2004年 | 537篇 |
2003年 | 569篇 |
2002年 | 514篇 |
2001年 | 890篇 |
2000年 | 834篇 |
1999年 | 661篇 |
1998年 | 352篇 |
1997年 | 298篇 |
1996年 | 268篇 |
1995年 | 261篇 |
1994年 | 307篇 |
1993年 | 269篇 |
1992年 | 435篇 |
1991年 | 478篇 |
1990年 | 430篇 |
1989年 | 457篇 |
1988年 | 420篇 |
1987年 | 452篇 |
1986年 | 429篇 |
1985年 | 448篇 |
1984年 | 380篇 |
1983年 | 421篇 |
1982年 | 317篇 |
1981年 | 306篇 |
1980年 | 232篇 |
1979年 | 319篇 |
1978年 | 231篇 |
1977年 | 197篇 |
1976年 | 174篇 |
1975年 | 160篇 |
1974年 | 185篇 |
1973年 | 169篇 |
1972年 | 146篇 |
1971年 | 139篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
921.
Jordan Bechtold Caitlin Cavanagh Elizabeth P. Shulman Elizabeth Cauffman 《Journal of youth and adolescence》2014,43(11):1903-1913
Although impulsivity is one of the strongest psychological predictors of crime, it is unclear how well impulsivity, measured at a specific moment in adolescence, predicts criminal behavior months or years into the future. The present study investigated how far into the future self-reports and parents’ reports of a youth’s impulsivity predicted whether he engaged in illegal behavior, whether one reporter’s assessment was more predictive than the other’s, and whether there is value in obtaining multiple reports. Data were obtained from a 6-year longitudinal study of adjudicated juvenile offenders (n = 701 mother-son dyads). Youth (m = 15.93 years old; sd = 1.14) and their mothers independently reported on adolescents’ impulsivity at the initial assessment. We examined the prospective correlation of these measures with illegal behavior, assessed by official records of arrests and youths’ self-reports of offending across the 72-month study period. Youths’ and mothers’ reports of the adolescents’ impulsivity were weakly, but significantly, correlated with one another. Furthermore, mothers’ ratings of their sons’ impulsivity predicted arrest up to 6 years into the future, whereas youths’ reports did not significantly predict arrest beyond 30 months. With respect to youths’ self-reports of offending, mothers’ ratings of impulsivity again predicted farther into the future (as late as 6 years later) than did youths’ self-reports of impulsivity, which were not predictive beyond 4 years. However, across the first 4 years, youths’ self-reports of impulsivity explained more variance in self-reported offending than did mothers’ ratings. The results underscore the endurance of the predictive utility of an assessment of impulsivity and the importance (and accuracy) of parents’ reports of developmental constructs, even when their children are adolescents. 相似文献
922.
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
923.
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
924.
Jungmeen Kim-Spoon Julee P. Farley Christopher Holmes Gregory S. Longo Michael E. McCullough 《Journal of youth and adolescence》2014,43(5):745-756
Empirical evidence suggests that religiousness is related negatively to adolescent substance use; yet, we know little about how such protective effects might occur. The current study examined whether parents’ and adolescents’ religiousness are associated positively with parental, religious, and self-monitoring, which in turn are related to higher self-control, thereby related to lower adolescent substance use. Participants were 220 adolescents (45 % female) who were interviewed at ages 10–16 and again 2.4 years later. Structural equation modeling analyses suggested that higher adolescents’ religiousness at Time 1 was related to lower substance use at Time 2 indirectly through religious monitoring, self-monitoring, and self-control. Higher parents’ religiousness at Time 1 was associated with higher parental monitoring at Time 2, which in turn was related to lower adolescent substance use at Time 2 directly and indirectly through higher adolescent self-control. The results illustrate that adolescents with high awareness of being monitored by God are likely to show high self-control abilities and, consequently, low substance use. The findings further suggest that adolescents’ religiousness as well as their religious environments (e.g., familial context) can facilitate desirable developmental outcomes. 相似文献
925.
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
926.
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
927.
Hafen CA Allen JP Mikami AY Gregory A Hamre B Pianta RC 《Journal of youth and adolescence》2012,41(3):245-255
Student engagement is an important contributor to school success, yet high school students routinely describe themselves as
disengaged. Identifying factors that alter (increase) engagement is a key aspect of improving support for student achievement.
This study investigated students’ perceptions of autonomy, teacher connection, and academic competence as predictors of changes
in student engagement within the classroom from the start to the end of a course. Participants were 578 (58% female) diverse
(67.8% White, 25.2% African American, 5.1% Hispanic, 1.2% Asian American) high school students from 34 classrooms who provided
questionnaire data both at the start and the end of a single course. Novel results from a cross-lagged model demonstrated
that students who perceived their classrooms as allowing and encouraging their own autonomy in the first few weeks increased
their engagement throughout the course, rather than the typical decline in engagement that was demonstrated by students in
other classrooms. This finding is unique in that it extended to both students’ perceptions of engagement and observations
of student engagement, suggesting a fairly robust pattern. The pertinence of this finding to adolescent developmental needs
and its relationship to educational practice is discussed. 相似文献
928.
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
929.
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
930.
Schwartz SJ Klimstra TA Luyckx K Hale WW Meeus WH 《Journal of youth and adolescence》2012,41(9):1208-1225
The longitudinal effects among self and identity processes, and between these processes and internalizing symptoms, are not well understood. As a result, the present study was designed to ascertain the over-time effects among identity commitment, reconsideration of commitments, and self-concept clarity, as well as to map the interplay of these self and identity processes with anxiety and depressive symptoms in early adolescence. A sample of 923 Dutch adolescents (mean age 12.4 years at Time 1; 49.3% female) participated at each of five annual assessments. Multivariate growth curve and cross-lagged panel models indicated that the association between self-concept clarity and commitment was bidirectional, that reconsideration occurs based on problems or dissatisfaction with self-concept clarity and with identity commitments, and that self-concept clarity (but not commitment or reconsideration) temporally precedes depressive and anxiety symptoms. Results are discussed in terms of the structure of the self-system and its associations with internalizing symptoms. 相似文献