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   5881篇
  免费   266篇
各国政治   401篇
工人农民   204篇
世界政治   622篇
外交国际关系   427篇
法律   2583篇
中国政治   55篇
政治理论   1792篇
综合类   63篇
  2023年   40篇
  2022年   21篇
  2021年   43篇
  2020年   91篇
  2019年   119篇
  2018年   208篇
  2017年   207篇
  2016年   259篇
  2015年   146篇
  2014年   162篇
  2013年   948篇
  2012年   186篇
  2011年   188篇
  2010年   160篇
  2009年   167篇
  2008年   209篇
  2007年   252篇
  2006年   222篇
  2005年   206篇
  2004年   213篇
  2003年   170篇
  2002年   181篇
  2001年   108篇
  2000年   111篇
  1999年   116篇
  1998年   97篇
  1997年   93篇
  1996年   72篇
  1995年   73篇
  1994年   75篇
  1993年   83篇
  1992年   75篇
  1991年   71篇
  1990年   70篇
  1989年   59篇
  1988年   72篇
  1987年   53篇
  1986年   61篇
  1985年   48篇
  1984年   49篇
  1983年   38篇
  1982年   33篇
  1981年   45篇
  1980年   24篇
  1979年   24篇
  1978年   27篇
  1977年   23篇
  1976年   22篇
  1975年   17篇
  1974年   32篇
排序方式: 共有6147条查询结果,搜索用时 15 毫秒
211.
Allegations of child maltreatment and neglect, including child sexual abuse, in the context of child custody disputes pose particular challenges for child protection services, family law professionals and the courts to identify children at risk of harm, as well as children impacted and exposed to other risk factors. Accurately identifying child maltreatment requires assessing the background, the history and the context of the allegations in order to differentiate confirmed, unfounded, and fabricated allegations. The paper provides a review of the history and current understanding of allegations within the context of child custody disputes by considering the connections of fabricated allegations to the theory of alienation and the role of gatekeeping. The paper then examines the social science literature regarding allegations within child protection investigations (the prevalence, types of maltreatment, reporter of allegations, and case outcomes) and explores the factors that have contributed to the challenges faced by child protection services to investigate and make determinations regarding allegations within the context of child custody disputes. We argue for early assessment protocols for child protection services to screen child custody cases, to differentiate allegations of alienation from other types of harm, to enhance role clarity in these volatile situations, to refrain from “taking sides” and to work collaboratively with the family law community. Lastly, we offer legal implications to improve collaboration between child protection services and the family law field to better respond to these complex cases.  相似文献   
212.
213.
A simple, quick, selective, sensitive, and effective field-friendly method capable of being used by nonexperts has been developed for detecting mitragynine in Mitragyna speciosa (kratom) using surface-enhanced Raman spectroscopy (SERS). Over 100 samples and blanks (known to be either positive or negative for the presence of mitragynine) were examined in duplicate using five identical handheld Raman spectrometers, which provided a data set of over 1,000 examinations. Based on the results of these analyses, the method yielded a true-positive rate of 99.3%, a true-negative rate of 97.9%, a false-positive rate of 2.1%, and a false-negative rate of 0.7%. The average minimum detectable concentration (Cm) of mitragynine that reproducibly yielded a match for one of the library spectra on all five instruments was determined to be 342 ng/mL (ppb). This Cm value is a conservative estimate considering that the extraction process was not fully optimized by this study, which was not necessary since the Cm value achieved was well below typical mitragynine concentrations in kratom (1.3–2.3%). The method is ideal (i) for prioritizing samples for additional testing using other more time-consuming laboratory-based techniques needed to detect and quantify mitragynine and (ii) for field use at international mail facility (IMF) satellite laboratories to help interdict kratom and prevent this dangerous product from reaching the U.S. supply chain.  相似文献   
214.
Postmortem magnetic resonance imaging (MRI) is rarely used for the radiologic assessment of gunshot injuries, although it has clear advantages over postmortem computed tomography (CT) with regard to the imaging of soft tissue injuries. Another benefit in using MRI is that lodged projectiles composed of nonferromagnetic material such as lead present only marginal metal artifacts compared with severe artifacts on CT. This case report presents CT and MRI findings in a case with two gunshot wounds to the neck: a perforating wound and a nonperforating wound with a lead bullet lodged in the cervical spine. The decedent underwent CT and MRI before the scheduled autopsy. A ring of radiopaque material under the dermis in the fatty tissue was identified at both entrance wounds on CT, which was indicative of contact shots. The perforating gunshot was clearly indicated on CT by bullet fragments along the wound channel through the perforated 6th cervical vertebra and the fractured cricoid cartilage at the exit wound. The second trajectory, however, was only assumed based on the presence of gunshot residues at the entrance wound and the position of the lodged bullet. The radiologic assessment was severely impeded by the metal artifacts on CT. Barely noticeable metal artifacts on MRI allowed for clear visualization of the soft tissue injuries and the ruptured medulla oblongata. Only MRI clarified the soft tissue injuries of the brainstem noninvasively, which could provide specific and graphic information on the rapidity of death and the incapacitation of the victim.  相似文献   
215.
This study examined gender differences in cross-gender violence perpetration and victimization (ranging from mild, e.g., push, to severe, e.g., assault with a knife or gun) and attitudes toward dating conflict, among an urban sample of 601 early adolescents (78% African-American). Comparisons across gender groups for cross-gender (e.g., female-to-male) violence perpetration and victimization indicated higher levels of perpetration for girls and higher levels of victimization for boys. Girls also reported higher levels of verbal and physical violence toward partners with regard to attitudes toward dating conflict. A path model was specified and indicated that cross-gender violence perpetration, harsh parenting, peer deviance, low family income, and neighborhood hazards accounted for significant variation in attitudes toward dating conflict. Findings were discussed regarding the need to identify developmental precursors of dating violence in early adolescence and to focus prevention efforts on components (e.g., social skills, coping strategies) necessary to prevent the onset and escalation of adolescent dating violence.
Sylvie MrugEmail:
  相似文献   
216.
The article presents a comparative analysis of the religious underpinnings of 19 liberal democracies in the West and their relevance for contemporary minority politics. The democratic relevance of religion is conceptualised as stemming from actors (churches, religious parties) and from historical and structural factors such as confessional patterns, relationships between state and church and degrees of secularisation in 19 democracies with a Christian background. The article’s historical mapping demonstrates that democratic development has occurred in distinct patterns rooted in the Catholic?Protestant divide. It then demonstrates that there are distinct effects of this divide on minority politics. It is hypothesised that in line with the confessional patterning of democratisation, Catholic countries and actors seem to be more resistant to the pressures arising from religious pluralisation than Protestant ones and that, even after 9/11, there is no cross-national or cross-confessional convergence in these responses.  相似文献   
217.
The investment approach to public service provision is now receiving considerable attention worldwide. By promoting data‐intensive assessments of baseline conditions and how government action can improve on them, the approach holds the potential to transform policy development, service implementation, and program evaluation. Recently, variations on the investment approach have been applied in Australia to explore the effectiveness of specific programs in employment training, criminal justice, and infrastructure development. This article reviews the investment approach, presents a Public Investment Checklist to guide such work, and discusses three examples. It concludes by considering the implications of investment thinking for the work of policy designers and public managers.  相似文献   
218.
219.
This article explores the phenomenon of the enduring state control over the Russian natural gas sector. We suggest that explanations of the underlying motives can be classified under two broad theoretical categories: idealism and utilitarianism. Thus, we argue that state capitalism in the Russian natural gas industry can be understood through the idealistic claims of state power and of serving the national interest, which underpin the dominant perception of natural gas resources as a foreign policy tool. Moreover, we contend that although this perception is often considered as a product of the last decade, in fact it is rooted in history, as a legacy of the Soviet era.  相似文献   
220.
Pay for performance (PFP) remains one of the most controversial policy debates in the New Public Management reform era. Skepticism about PFP in the public sector is often grounded in theories of public service motivation that suggest a misalignment between PFP's focus on extrinsic market‐based pay incentives and intrinsically motivated government workers. Frequently missing from this analysis, however, is any consideration for whether PFP leads to positive “sorting” effects on the composition of a government agency's workforce through attraction, selection, and attrition processes. Using data from two waves of the Schools and Staffing Survey, the authors examine whether PFP influences the sorting patterns of K–12 public schoolteachers across U.S. school districts. Findings show that, on average, school districts that adopted PFP secured new teacher hires who had graduated from colleges and universities with average SAT scores that were about 30 points higher than the new teacher cohorts hired by districts that did not adopt PFP.  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