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   17630篇
  免费   1238篇
各国政治   717篇
工人农民   848篇
世界政治   1266篇
外交国际关系   545篇
法律   12298篇
中国共产党   2篇
中国政治   112篇
政治理论   2990篇
综合类   90篇
  2023年   80篇
  2021年   90篇
  2020年   435篇
  2019年   458篇
  2018年   570篇
  2017年   587篇
  2016年   666篇
  2015年   512篇
  2014年   539篇
  2013年   1821篇
  2012年   510篇
  2011年   520篇
  2010年   556篇
  2009年   566篇
  2008年   532篇
  2007年   524篇
  2006年   535篇
  2005年   453篇
  2004年   440篇
  2003年   361篇
  2002年   414篇
  2001年   679篇
  2000年   607篇
  1999年   482篇
  1998年   239篇
  1997年   173篇
  1996年   193篇
  1995年   193篇
  1994年   171篇
  1993年   175篇
  1992年   305篇
  1991年   313篇
  1990年   296篇
  1989年   276篇
  1988年   306篇
  1987年   262篇
  1986年   323篇
  1985年   317篇
  1984年   247篇
  1983年   226篇
  1982年   179篇
  1981年   156篇
  1980年   143篇
  1979年   219篇
  1978年   117篇
  1977年   92篇
  1975年   94篇
  1974年   125篇
  1973年   79篇
  1972年   78篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
881.
This prospective study examined the usefulness of seven selected variables from Jessor and Jessor's problem behavior theory in predicting the future smoking levels of adolescent experimental smokers. Experimental smokers were identified through a survey of 2,550 seventh- and eighth-grade students assessing subjects' current smoking levels as well as subjects' responses to the selected variables. Twelve months later the entire sample was resurveyed to assess subsequent smoking levels of subjects initially reporting experimental smoking. Experimental smokers who responded to both surveys (n=225) were subjects of the present study. The full model discriminant function was significant in discriminating between the two groups; 68% of the subjects were correctly classified. This moderately successful hit rate was 24% better than what could be expected by chance. Increased smokers had lower expectations for academic achievement, had stronger beliefs about the positive functions of smoking, and perceived more smoking among their classmates and close friends. Educational interventions are suggested.Received Ph.D. from the University of Nebraska in 1987. Research interests include human behavior change strategies.Received Ph.D. from University of Illinois in 1968. Research interests include behavior and health.  相似文献   
882.
883.
884.
The stepping-stone theory of progression into drug use is examined, based on the alcohol and other drug use of over 27,000 seventh-through eighth-grade students in New York State. The data show that students do not use illicit drugs unless they also use alcohol. White, black and Hispanic students all tend to initiate the use of drugs in the following order-alcohol, marijuana, pills, and hard drugs. Among blacks and Hispanics, pills are not as important a transition between marijuana and hard drugs as they are among whites. Cigarettes form an important step between alcohol and marijuana use for younger students, particularly for females. Since alcohol serves as the gateway to all other drug use, prevention approaches that control and limit alcohol use among adolescents may be warranted.He received his Ph. D. in Psychology for the State University of New York at Buffalo in 1976. His research interests are the social and psychological correlates of drinking.She received her Ph.D. in Sociology from the State University of New York at Buffalo in 1983.  相似文献   
885.
This study examined the influence of pubertal timing upon family interactions in normal and psychiatric adolescent samples. An important feature of our approach is its emphasis upon micro-analysis of family behaviors (individual speeches) and family processes (theoretically specified speech pairings). Rather than assume that global family patterns (e.g., power) shift in response to pubertal changes, we follow how types of speeches and speech sequences are associated with different pubertal timing. Using the previously constructed family coding system, the Constrainig and Enabling Coding System, we found that on-time adolescents and their parents differed from both off-time groups (early or late). These results are discussed in terms of current implications and suggestions for future research.An earlier version of this paper was presented at the SRCD Study Group on Timing of Maturation, October, 1983, at the Education Testing Service, Princeton, NJ. This research was supported by NICHD Grant 1 R01 HD18684-01, and an NIMH Research Scientist Award (Dr. Hauser).Received his Ph.D. from Harvard University. Research interest is adolescent development within the family and impact of chronic illness on adolescent development and family interaction.Received her B.A. from Wellesley College. Research interests are in humor and attractiveness.Received his M.A. from Boston University. Research interests are in methodology and statistics.Received Ed.D. from Harvard University. Research interests are in adolescent development within the family, and family coping with stress.Received M.D. from University of Chicago. Research interests are in psychosocial aspects of diabetes.Received Ed.D. from Harvard University. Research interests are in developmental psychopathology, and moral and ego development.Received Ph.D. from Ohio State University. Research interests are in assessment of ego development and family systems.Received Ph.D. from University of Miami. Research interests are in family studies and adolescent development.  相似文献   
886.
Relationships among major life events, perceived social support, and psychological disorder were assessed in a sample of older adolescents. Negative life events and satisfaction with social support were significantly and independently related to a range of psychological symptoms. Further, the relationship between negative events and disorder was moderated by gender, the types of events experienced, and anticipated change in the psychosocial environment. The importance of the use of standardized and psychometrically sound measures of life events, social support, and psychological disorder is highlighted.Received his Ph.D. from UCLA in 1980. An assistant professor, he is currently investigating stress and coping among children and adolescents.Received her Ph.D. from the University of Vermont in 1985. An assistant professor, she is currently studying social support.Received Ed. M. from Harvard Universtiy. He is a doctoral student in clinical psychology interested in the role of social support in coping with stress during adolescence.Received her BA from the University of Vermont. She is a doctoral student in clinical psychology.  相似文献   
887.
Over the past two decades states have significantly increased their use of competitive bidding to purchase health and social services from private agencies. Competitive contracting is thought to facilitate program administration, to reduce costs, and to increase the quality of delivered services. We evaluate these claims in light of Massachusetts' experience with competitive contracting for mental health care. We find that few of the expected benefits are achieved. In practice, supposedly competitive bidding systems often degenerate into administratively complicated negotiations between the state and private monopolies. This results in higher costs and lower quality of services. In light of this negative assessment, three strategies for reform are proposed and evaluated.  相似文献   
888.
889.
890.
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