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   6776篇
  免费   133篇
各国政治   157篇
工人农民   655篇
世界政治   269篇
外交国际关系   218篇
法律   4375篇
中国政治   36篇
政治理论   1186篇
综合类   13篇
  2021年   27篇
  2020年   50篇
  2019年   52篇
  2018年   488篇
  2017年   521篇
  2016年   406篇
  2015年   82篇
  2014年   79篇
  2013年   280篇
  2012年   167篇
  2011年   456篇
  2010年   498篇
  2009年   347篇
  2008年   386篇
  2007年   358篇
  2006年   105篇
  2005年   103篇
  2004年   130篇
  2003年   119篇
  2002年   96篇
  2001年   186篇
  2000年   133篇
  1999年   104篇
  1998年   40篇
  1997年   51篇
  1996年   44篇
  1995年   71篇
  1994年   60篇
  1993年   54篇
  1992年   81篇
  1991年   86篇
  1990年   77篇
  1989年   63篇
  1988年   84篇
  1987年   81篇
  1986年   98篇
  1985年   108篇
  1984年   91篇
  1983年   88篇
  1982年   42篇
  1981年   36篇
  1979年   39篇
  1978年   34篇
  1977年   30篇
  1975年   31篇
  1974年   45篇
  1972年   27篇
  1971年   31篇
  1970年   30篇
  1968年   32篇
排序方式: 共有6909条查询结果,搜索用时 453 毫秒
271.
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   
272.
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   
273.
Although adolescents often participate in multiple extracurricular activities, little research has examined how the breadth of activities in which an adolescent is involved relates to school-related affect and academic performance. Relying on a large, multi-ethnic sample (N = 864; 55.9% female), the current study investigated linear and non-linear relationships of 11th grade activity participation in four activity domains (academic/leadership groups, arts activities, clubs, and sports) to adolescents’ sense of belonging at school, academic engagement, and grade point average, contemporarily and in 12th grade. Results of multiple regression models revealed curvilinear relationships for sense of belonging at school in 11th and 12th grade, grade point average in 11th grade, and academic engagement in 12th grade. Adolescents who were moderately involved (i.e., in two domains) reported a greater sense of belonging at school in 11th and 12th grade, a higher grade point average in 11th grade, and greater academic engagement in 12th grade, relative to those who were more or less involved. Furthermore, adolescents’ sense of belonging at school in 11th grade mediated the relationship of domain participation in 11th grade to academic engagement in 12th grade. This study suggests that involvement in a moderate number of activity domains promotes positive school-related affect and greater academic performance. School policy implications and recommendations are discussed.  相似文献   
274.
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   
275.
Despite evidence that neighborhoods confer both risk and resilience for youth development, the existing neighborhood research has a number of methodological limitations including lack of diversity in neighborhoods sampled and neighborhood characteristics assessed. The purpose of this study was to address these methodological limitations of existing research and to examine the relationship of neighborhood structural and social characteristics to family-level social processes and teacher-reported social competence during early adolescence. The study sample of 3,624 fifth graders (51?% girls) was ethnically diverse, including roughly even proportions of non-Hispanic White, non-Hispanic Black, and Hispanic youth. Neighborhood measures included economic disadvantage derived from the U.S. Census, physical and social disorder obtained by direct observation, and social capital from parental reports. Family-level social processes included parent reported family cohesion and youth reported maternal and paternal nurturance. We found that neighborhood factors significantly associated with youth social aggression and social competence but not social withdrawal, after controlling for individual demographic characteristics and parenting factors. There was limited evidence of moderation of family influences by neighborhood characteristics as well as the moderation of neighborhood effects by children’s gender. Neighborhood physical disorder was associated with increased social aggression among boys but with increased social withdrawal among girls. Implications of the study’s findings for research on neighborhoods and adolescent development and the development of preventive interventions are discussed.  相似文献   
276.
277.
Adolescence is a challenging developmental period marked with declines in emotional well-being; however, self-compassion has been suggested as a protective factor. This cross-sectional survey study (N?=?765, grades 7th to 12th; 53?% female; 4?% Hispanic ethnicity; 64?% White and 21?% Black) examined whether adolescents’ self-compassion differed by age and gender, and secondly, whether its associations with emotional well-being (perceived stress, life satisfaction, distress intolerance, depressive symptoms, and anxiety) also differed by age and gender. The findings indicated that older females had the lowest self-compassion levels compared to younger females or all-age males. Self-compassion was associated with all emotional well-being measures, and gender and/or age moderated the associations with anxiety and depressive symptoms. Among older adolescents, self-compassion had a greater protective effect on anxiety for boys than for girls. Additionally, older adolescents with low and average self-compassion had greater levels of depressive symptoms than those with high self-compassion. These results may inform for whom and at what age self-compassion interventions may be implemented to protect adolescents from further declines in emotional well-being.  相似文献   
278.
Justice-involved youth have high rates of psychiatric diagnoses, and these youth are often placed out-of-home, although evidence identifies several negative implications of juvenile confinement, especially for youth with psychopathology. Furthermore, youth in the justice system may be processed differently based on gender. As males and females tend to manifest symptoms differently, the psychopathology of youth may act to moderate the relationship between gender and placement in the juvenile justice system. The present study used a large, diverse sample (n?=?9?851, 19.8?% female) to examine whether youth placed in various types of out-of-home facilities differed in terms of externalizing, internalizing, substance use, or comorbid disorders, and to determine the predictive value of mental health diagnoses in placement decisions. The moderation effect of psychopathology and substance use on the relationship between gender and placement also was explored. The results indicated that each type of disorder differed across placements, with internalizing being most prevalent in non-secure, and externalizing, comorbid, and substance use being most prevalent in secure settings. Mental health diagnoses improved the prediction of placement in each out-of-home placement beyond legal and demographic factors such that externalizing and substance use disorders decreased the likelihood of placement in non-secure settings, and internalizing, externalizing, and substance use disorders increased the likelihood of placement in secure and state-secure facilities. The relationship between internalizing pathology and placement in more secure facilities was moderated by externalizing pathology. The relationship between gender and placement was significantly moderated by mental health such that females with mental health diagnoses receive less secure placements. Implications for policymakers and practitioners are discussed, as well as implications for reforming juvenile justice within a developmental approach.  相似文献   
279.
Are internalizing and externalizing behavior problems interrelated via mutually reinforcing relationships (with each behavior leading to increases over time in levels of the other behavior) or mutually suppressing relationships (with each behavior leading to decreases over time in levels of the other behavior)? Past research on the directionality of these relationships has led to ambiguous results, particularly in adolescence. Furthermore, the extent to which prior results will generalize to adolescents with low levels of cognitive abilities remains unknown. This second limit is particularly important, given that these adolescents are known to present higher levels of externalizing and internalizing behaviors than their peers with average-to-high levels of cognitive abilities, and that the mechanisms involved in the reciprocal relationships between these two types of behaviors may differ across both populations. This study examines the directionality of the longitudinal relationships between externalizing and internalizing behavior problems as rated by teachers across three measurement waves (corresponding to Grades 8–10) in matched samples of 138 adolescents (34.78?% girls) with low levels of cognitive abilities and 556 adolescents (44.88?% girls) with average-to-high levels of cognitive abilities. The results showed that the measurement structure was fully equivalent across time periods and groups of adolescents, revealing high levels of developmental stability in both types of problems, and moderately high levels of cross-sectional associations. Levels of both internalizing and externalizing behaviors were higher among adolescents with low levels of cognitive abilities relative to those with average-to-high levels of cognitive abilities. Finally, the predictive analyses revealed negative reciprocal longitudinal relationships (i.e., mutually suppressing relationships) between externalizing and internalizing problems, a result that was replicated within samples of adolescents with low, and average-to-high levels of cognitive ability.  相似文献   
280.
Early alcohol use is associated with multiple negative outcomes later in life, including substance use disorders. Identification of factors related to this very early risk indicator can help inform early prevention efforts. This study prospectively examined the relationship between childhood adversities and early initiation of alcohol use (by age 14) among Puerto Rican youth, the Latino subgroup at highest risk for alcohol use disorders in adulthood. The data come from the Boricua Youth Study, a longitudinal study of Puerto Rican youth in two sites (South Bronx, New York, and the standard metropolitan area of San Juan, Puerto Rico). We focus on youth who were ages 10 and older at Wave 1 [M age at Wave 1 (SE)?=?11.64(0.05), N?=?1259, 48.85?% females]. Twelve childhood adversities were measured at Wave 1 and include 10 adverse childhood experiences commonly studied and two additional ones (exposure to violence and discrimination) that were deemed relevant for this study’s population. Early initiation of alcohol use was determined based on youth report at Waves 1 through 3 (each wave 1 year apart). Cox proportional hazards models showed that, when considered individually, adversities reflecting child maltreatment, parental maladjustment, and sociocultural stressors were related to early initiation of alcohol use. Significant gender interactions were identified for parental emotional problems and exposure to violence, with associations found among girls only. Adversities often co-occurred, and when they were considered jointly, physical and emotional abuse, parental antisocial personality, and exposure to violence had independent associations with early alcohol use, with a stronger influence of exposure to violence in girls compared to boys. The accumulation of adversities, regardless of the specific type of exposure, increased the risk for starting to drink at a young age in a linear way. The associations between childhood adversities and early alcohol use were generally consistent across sociocultural contexts, in spite of differences in the prevalence of exposure to adversity. Our findings highlight the importance of targeting multiple adversities and expanding the notion of adversity to capture the experiences of specific groups more adequately.  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