全文获取类型
收费全文 | 16530篇 |
免费 | 234篇 |
专业分类
各国政治 | 696篇 |
工人农民 | 1357篇 |
世界政治 | 740篇 |
外交国际关系 | 641篇 |
法律 | 9646篇 |
中国共产党 | 1篇 |
中国政治 | 87篇 |
政治理论 | 3536篇 |
综合类 | 60篇 |
出版年
2020年 | 93篇 |
2019年 | 118篇 |
2018年 | 1398篇 |
2017年 | 1365篇 |
2016年 | 1174篇 |
2015年 | 189篇 |
2014年 | 198篇 |
2013年 | 1013篇 |
2012年 | 362篇 |
2011年 | 1096篇 |
2010年 | 1160篇 |
2009年 | 731篇 |
2008年 | 945篇 |
2007年 | 904篇 |
2006年 | 253篇 |
2005年 | 264篇 |
2004年 | 362篇 |
2003年 | 348篇 |
2002年 | 190篇 |
2001年 | 300篇 |
2000年 | 258篇 |
1999年 | 243篇 |
1998年 | 121篇 |
1997年 | 102篇 |
1996年 | 98篇 |
1995年 | 109篇 |
1994年 | 120篇 |
1993年 | 88篇 |
1992年 | 135篇 |
1991年 | 175篇 |
1990年 | 164篇 |
1989年 | 158篇 |
1988年 | 165篇 |
1987年 | 183篇 |
1986年 | 167篇 |
1985年 | 162篇 |
1984年 | 149篇 |
1983年 | 142篇 |
1982年 | 99篇 |
1981年 | 96篇 |
1980年 | 72篇 |
1979年 | 143篇 |
1978年 | 109篇 |
1977年 | 88篇 |
1976年 | 69篇 |
1975年 | 96篇 |
1974年 | 97篇 |
1973年 | 89篇 |
1972年 | 68篇 |
1971年 | 59篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
921.
Denise B. Kandel Victoria H. Raveis Mark Davies 《Journal of youth and adolescence》1991,20(2):289-309
The interrelationships of depression and suicide with adolescent drug use, delinquency, eating disorders, and the risk factors for these different problems were investigated among 597 9th and 11th graders in an urban high school. There is a strong association of drug use with suicidal ideation among girls, and a stronger relationship with attempts among girls and boys. Suicidal youths are ill-adjusted and display a lack of attachment and commitment to family and school. Causal models indicate that poor interpersonal interactions with parents, absence of peer interactions, and life events lead to depression, which in turn leads to suicidal ideation. Depressive symptoms are the strongest predictors of suicidal ideation. Among females, depression predicts drug involvement, and in turn, drug use increases suicidal ideation. Drug use is only one class of problem behaviors that constitutes a risk factor for suicidal behavior in adolescence. Delinquency and eating disorders also have direct effects on suicidal ideation beyond those of depressive affect. As for drug involvement, these problem behaviors are more predictive of suicidal behavior among girls than boys. Similarity and specificity of the predictors for problem behaviors within and between the sexes are discussed. Although young women use drugs to handle feelings of depression, drug use appears ineffective in the long run in relieving these depressive feelings. Understanding the dynamics of suicidal ideation in adolescence has important public health implications, since ideation is a strong predictor of attempts, especially among females.Revised version of a presentation at the Workshop on Adolescent Depression, Princeton, NJ, June 3, 1987.Work on this research has been partially supported by Research Grants DA00064, DA01097, DA03196, and DA02867, and by Research Scientist Award DA00081 from the National Institute on Drug Abuse; and awards from the John D. and Catherine MacArthur Foundation and the Research Foundation for Mental Hygiene, New York State Psychiatric Institute. Partial support for computer costs was provided by Mental Health Clinical Research Center Grant MH30906-07 from NIMH to the New York State Psychiatric Institute.Received Ph.D. in Sociology from Columbia University. Research interests include adolescent psychosocial development, epidemiology and risk factors for drug use, and interpersonal networks.Work on this research was carried out while a Research Associate at the School of Public Health, Columbia University. Received Ph.D. in Sociology from Columbia University. Research interests include personal networks and social support systems in chronic illness, societal factors in mental health, psychosocial consequences of drug use and abuse, panel mortality, and survey methodology.Received M.P.H. from Columbia University. Research interests include reliability and child psychiatry. 相似文献
922.
Susan J. Paxton Eleanor H. Wertheim Kay Gibbons George I. Szmukler Lynne Hillier Janice L. Petrovich 《Journal of youth and adolescence》1991,20(3):361-379
Body image and weight loss beliefs and behaviors were assessed in 341 female and 221 male high school students. Estimates of body dissatisfaction varied depending on the measurement strategy used. Despite having similar weight distributions around the expected norm, girls were significantly more dissatisfied with their bodies than boys. Body Mass Index was positively related to body dissatisfaction in girls and boys, while higher exercise levels were related to higher body satisfaction in boys. Nearly two-thirds of girls and boys believed being thinner would have an impact on their lives, but the majority of girls believed this would be positive while the majority of boys believed this would be negative. Thirteen percent of female subjects reported using one or more extreme weight loss behavior at least weekly. Beliefs regarding the effectiveness of different weight loss measures were assessed. Weight loss behaviors in this Australian sample appear similar to comparable U.S. samples.Received Ph.D. from University of Tasmania. Main research interest in body image, weight loss behaviors, and eating disorders.Received Ph.D. from University of Connecticut. Main research interest in body image, eating disorders and weight loss behaviors.Dietitian degree from Melbourne University, Melbourne. Main research interest in eating practices and clinical outcome.M.D. from University of Melbourne, D.P.M. from U.K. FRC Psych. Main research interests in eating disorders.B.B.Sc.(Hons.) received from La Trobe University, Melbourne, B.A. received from University of Minnesota, Duluth. Main research interest in attitudes and attributions.B.A. Received from University of Minnesota, Duluth. Main research interest in adolescence and eating disorders. 相似文献
923.
William H. Riker George Bittlingmayer David N. Laband Randall G. Holcombe 《Public Choice》1991,72(2-3):237-243
924.
925.
Conflicts between favorites and underdogs are everyday phenomena. We examine their strategic behavior in an experimental contest, and find behavior partially consistent with predictions. Favorites given a first-mover advantage do overcommit effort relative to Nash. Underdogs often select the best response effort level given the favorite's move. Overall dissipation of the prize was significantly higher with the strategic commitment relative to Nash. qu]Life is not so mathematically idiotic that it allows only the big to eat the small, for it happens just as often that the bee kills the lion, or at least drives it mad. 相似文献
926.
The influence of self-esteem on the use of status considerations as determinants of interpersonal acceptance was studied in a sample of 722 Israeli students from integrated junior high schools. The students completed a self-esteem questionnaire as well as the Interpersonal Relation Assessment Technique, a measure assessing willingness to engage in activities of increasing intimacy with classmates. Data analysis indicated a general preference for targets of higher educational level and high-status ethnic origin. These categorical preferences were more pronounced among high rather than low self-esteem students, irregardless of their own educational standing or ethnic origin. The findings were consistent with the thrust of cost-benefit analyses suggested by social exchange theories, in which self-esteem is viewed as one's globalized perception of social worth. The results suggest that individuals with high self-esteem may be more likely to see themselves as equals to higher status others and seek out their company than would their low self-esteem counterparts. Alternately, those with high self-esteem may be more motivated by social ambition and less by fear of rejection.Received doctorate from UCLA. Studies issues related to self-esteem and social relationships, as well as stress and coping in childhood and adolescence.Received doctorate from the University of Texas at Austin. Research deals with interethnic relations, religious education, and post traumatic stress disorders. 相似文献
927.
Mark D. Weist Abby H. Freedman David A. Paskewitz Eric J. Proescher Lois T. Flaherty 《Journal of youth and adolescence》1995,24(6):705-721
Explored the influence of life stress as mediated or moderated by locus of control, family environment, social support, and coping style on psychological adjustment and school performance in 164 ninth graders from Baltimore. Gender differences in findings were shown. For boys, family cohesion was the only variable found to protect against the effects of stress. Family cohesion did not serve protective functions for girls, and along with overall social support, was associated with increased vulnerability to school problems. The report of problem-focused coping strategies exerted a number of protective functions for girls only. External locus of control was found to increase boys' and girls' vulnerability to the effects of life stress. Empirical development of interventions to improve the psychosocial adjustment of inner-city adolescents is discussed.Received Ph.D. from Virginia Polytechnic Institute and State University in 1991. Research interests include evaluation of school mental health services, empirical development of interventions for children, and the impact of violence on urban youth.Received B.A. from Cornell University. Interests include stress and coping in children, identification of resilience factors, and evaluation of child mental health systems of care.Received Ph.D. from the University of Oklahoma in 1967. Research interests include psychophysiology, sleep disorders, and biofeedback and instrumentation.Received B.A. from Loyola College. Interested in applied work with adolescents and adults.Received M.D. from Duke University in 1968. Research interests include training in child and adolescent psychiatry, adolescent psychopathology, and the development of school mental health programs. 相似文献
928.
Joseph Fisher R. Mark Isaac Jeffrey W. Schatzberg James M. Walker 《Public Choice》1995,85(3-4):249-266
Numerous laboratory experiments have investigated the performance of several processes for providing public goods through voluntary contributions. This research has been able to identify features of the institution or environment which are reliably likely to produce outcomes “close” to the free riding outcome or “substantially” greater than the pessimistic prediction of standard models. One such feature is the “marginal per-capita return” (MPCR) from the public good. Various authors have altered MPCR between groups or for an entire group at the same time. The experiments reported here address a different question, “What would happen if, within a group, some persons faced a ‘high’ MPCR while others faced a ‘low’ MPCR?” 相似文献
929.
930.