全文获取类型
收费全文 | 710篇 |
免费 | 22篇 |
专业分类
各国政治 | 35篇 |
工人农民 | 146篇 |
世界政治 | 34篇 |
外交国际关系 | 40篇 |
法律 | 339篇 |
中国政治 | 13篇 |
政治理论 | 122篇 |
综合类 | 3篇 |
出版年
2023年 | 2篇 |
2021年 | 4篇 |
2020年 | 7篇 |
2019年 | 17篇 |
2018年 | 26篇 |
2017年 | 28篇 |
2016年 | 14篇 |
2015年 | 15篇 |
2014年 | 20篇 |
2013年 | 111篇 |
2012年 | 17篇 |
2011年 | 19篇 |
2010年 | 18篇 |
2009年 | 27篇 |
2008年 | 23篇 |
2007年 | 22篇 |
2006年 | 25篇 |
2005年 | 16篇 |
2004年 | 25篇 |
2003年 | 18篇 |
2002年 | 25篇 |
2001年 | 14篇 |
2000年 | 16篇 |
1999年 | 14篇 |
1998年 | 10篇 |
1997年 | 14篇 |
1996年 | 15篇 |
1995年 | 11篇 |
1994年 | 4篇 |
1993年 | 6篇 |
1992年 | 14篇 |
1991年 | 14篇 |
1990年 | 9篇 |
1989年 | 13篇 |
1988年 | 8篇 |
1987年 | 7篇 |
1986年 | 8篇 |
1985年 | 9篇 |
1984年 | 9篇 |
1983年 | 7篇 |
1982年 | 11篇 |
1981年 | 6篇 |
1980年 | 10篇 |
1979年 | 4篇 |
1978年 | 5篇 |
1977年 | 5篇 |
1976年 | 2篇 |
1973年 | 2篇 |
1970年 | 1篇 |
1969年 | 2篇 |
排序方式: 共有732条查询结果,搜索用时 15 毫秒
701.
Budowle B Adamowicz M Aranda XG Barna C Chakraborty R Cheswick D Dafoe B Eisenberg A Frappier R Gross AM Ladd C Lee HS Milne SC Meyers C Prinz M Richard ML Saldanha G Tierney AA Viculis L Krenke BE 《Forensic science international》2005,150(1):1-15
A total of 2443 male individuals, previously typed for the 13 CODIS STR loci, distributed across the five North American population groups African American, Asian, Caucasian, Hispanic, and Native American were typed for the Y-STR loci DYS19, DYS385a/b, DYS389I/II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438 and DYS439 using the PowerPlex Y System. All population samples were highly polymorphic for the 12 Y-STR loci with the marker DYS385a/b being the most polymorphic across all sample populations. The Native American population groups demonstrated the lowest genetic diversity, most notably at the DYS393 and DYS437 loci. Almost all of the 12-locus haplotypes observed in the sample populations were represented only once in the database. Haplotype diversities were greater than 99.6% for the African Americans, Caucasians, Hispanics, and Asians. The Native Americans had the lowest haplotype diversities (Apaches, 97.0%; Navajo, 98.1%). Population substructure effects were greater for Y-haplotypes, compared with that for the autosomal loci. For the apportionment of variance for the 12 Y-STRs, the within sample population variation was the largest component (>98% for each major population group and approximately 97% in Native Americans), and the variance component contributed by the major population groups was less than the individual component, but much greater than among sample populations within a major group (11.79% versus 1.02% for African Americans/Caucasians/Hispanics and 15.35% versus 1.25% for all five major populations). When each major population is analyzed individually, the R(ST) values were low but showed significant among group heterogeneity. In 692 confirmed father-son pairs, 14 mutation events were observed with the average rate of 1.57x10(-3)/locus/generation (a 95% confidence bound of 0.83x10(-3) to 2.69x10(-3)). Since the Y-STR loci reside on the non-recombining region of the Y chromosome, the counting method is one approach suggested for conveying an estimate of the rarity of the Y-haplotype. Because the Y-STR loci are not all in disequilibrium to the same extent, the counting method is a very conservative approach. The data also support that autosomal STR frequencies can be multiplied by the upper bound frequency estimate of a Y-haplotype in the individual population group or those pooled into major population groups (i.e., Caucasian, African American, Hispanic, and Asian). These analyses support use of the haplotype population data for estimating Y-STR profile frequencies for populations residing in North America. 相似文献
702.
The Internet opens a vast array of communication, entertainment, and educational resources for children; however, it also opens a gateway to home and school for offenders who wish to exploit children. A convenience sample of 225 cases published in the news media was examined. The cases were classified using law enforcement terminology to describe Internet offenders as traders, travelers, or combination trader-travelers. The media is seen as a critical source of information for the public to be aware of how the Internet is being used to commit sexual exploitation and sex crimes against children. 相似文献
703.
This paper illustrates one strategy for testing a theory ofeconomic influences on voting. We use a competitive equilibriummodel of the economy to determine the impact of an individual'seconomic position on his or her economic interests and, ultimately,political interests. We then test whether this impact is observedin voting behavior, addressing the resulting specification andestimation problems in the context of U.S. presidential electiondata. Our empirical results suggest that, despite these formidableproblems, we can usefully connect politicaleconomic modelsand discrete-choice (probit) models of voting. 相似文献
704.
705.
706.
Two studies were conducted to investigate the relationship between several nonintellectual personal attributes and satisfaction with acceleration among intellectually gifted students. First, two cohorts of gifted students (top 1% in ability and separated in age by five years) who had utilized acceleration during the course of their education were surveyed at age 18 and again at age 23. Overall, no strong relationships were found between satisfaction with acceleration and the nonintellectual factors at either age. Second, similar analyses were conducted for a subgroup of subjects, using the Adjective Check List and the Study of Values. Again, few significant correlations were found; the correlations that were statistically significant were small. These findings indicate that some non-intellectual personal attributes, which are often assumed important to the selection of students for acceleration or to the evaluation of participants in accelerative programs, actually may not be appropriate for these purposes.This research was supported by grants to Camilla Benbow from the National Science Foundation (MDR-8651737 and MDR-8855625) and an anonymous service agency. Further support was provided by scholarships to Mary Ann Swiatek from Oberlin College and from the Kappa Kappa Gamma Fraternity.Received M.S. in counseling psychology from Iowa State University. Research interests include social and emotional aspects of giftedness, and social coping among gifted adolescents.Received Ed.D. in educational psychology from the Johns Hopkins University. Research focuses upon intellectual talent. 相似文献
707.
708.
709.
Jacquelyn C. Campbell Paul Miller Mary M. Cardwell Ruth Ann Belknap 《Journal of family violence》1994,9(2):99-111
A longitudinal study of 114 women, all having serious problems in intimate relationships, recruited from the community was undertaken in order to investigate relationship and battering status over time. In the original sample (N=193), 97 women were battered and 96 were not battered, as determined by an adaptation of the Conflict Tactics Scale. Of the 114 who returned approximately 2 and 1/2 years later, only 25% of the 51 originally battered women were still in that category. Discriminant function analysis using a combination of variables from established instruments (depression, self-esteem, physical symptoms, self-care agency) and in depth interview (education, relationship control, relationship duration, childhood abuse) failed to distinguish those battered from those not abused at Time 2. Results do not support a learned helplessness model for most women experiencing abuse, and they suggest that battered women seen in the health care and/or social services systems should be supported in a process of healthy decision making about their relationship status. 相似文献
710.