全文获取类型
收费全文 | 3779篇 |
免费 | 128篇 |
专业分类
各国政治 | 130篇 |
工人农民 | 120篇 |
世界政治 | 231篇 |
外交国际关系 | 121篇 |
法律 | 2656篇 |
中国政治 | 35篇 |
政治理论 | 601篇 |
综合类 | 13篇 |
出版年
2021年 | 27篇 |
2020年 | 49篇 |
2019年 | 52篇 |
2018年 | 75篇 |
2017年 | 90篇 |
2016年 | 81篇 |
2015年 | 67篇 |
2014年 | 76篇 |
2013年 | 278篇 |
2012年 | 87篇 |
2011年 | 111篇 |
2010年 | 80篇 |
2009年 | 87篇 |
2008年 | 109篇 |
2007年 | 84篇 |
2006年 | 105篇 |
2005年 | 88篇 |
2004年 | 98篇 |
2003年 | 95篇 |
2002年 | 91篇 |
2001年 | 186篇 |
2000年 | 133篇 |
1999年 | 104篇 |
1998年 | 38篇 |
1997年 | 47篇 |
1996年 | 35篇 |
1995年 | 50篇 |
1994年 | 44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 | 86篇 |
1983年 | 80篇 |
1982年 | 38篇 |
1981年 | 36篇 |
1979年 | 34篇 |
1978年 | 32篇 |
1975年 | 31篇 |
1974年 | 45篇 |
1973年 | 24篇 |
1972年 | 27篇 |
1971年 | 31篇 |
1970年 | 30篇 |
1968年 | 32篇 |
排序方式: 共有3907条查询结果,搜索用时 15 毫秒
141.
Breana N. Peace M.S. James T. Pokines Ph.D. Peter M. Cummings M.Sc. M.D. Allen G. Harbaugh Ph.D. 《Journal of forensic sciences》2020,65(5):1416-1423
Hacking trauma is prevalent in forensic cases involving genocide and dismemberment, but research into the identification of this type of trauma is lacking. The present study examines characteristics of hacking and blunt force skeletal trauma in order to determine if there is a point at which blunt force trauma becomes distinguishable from hacking trauma. Ten implements with a range of blade angles (i.e., the striking surface of the implement) were used in conjunction with a controlled-force hacking device to impact 100 limb bones of white-tailed deer (Odocoileus virginianus). Observations of the trauma included the occurrence and degree of fragmentation, the entrance widths of the impacts, and composite scores of six hacking characteristics, especially the distinctive V-shaped kerf. ANOVA tests and regression analyses were used to assess the relationships between these characteristics and the blade angles. A significant relationship (p-value = 0.011) was found between the composite hacking scores and the blade angles, indicating that blunt force and hacking trauma can be distinguished. The entrance widths of the impacts exhibited a significant relationship with the blade angles (p-value = 0.037). There was also a significant relationship between the visibility of a V-shaped kerf in the bones (p-value = 0.003), with visibility decreasing around the 60° blade angle. These data should assist in establishing guidelines to differentiate hacking and blunt force skeletal trauma in cases where the implement is on a spectrum between sharp and blunt. 相似文献
142.
Owen Esaias M.Sc. Grant W. Noonan D.P.S. Shane Everist M.Sc. Michell Roberts B.B.Sc. Cassie Thompson M.Sc. Matt N. Krosch Ph.D. 《Journal of forensic sciences》2020,65(3):722-728
An important component of crime scene reconstruction is bloodstain pattern analysis (BPA). Where BPA concerns impact patterns, estimating the area of origin is critical information for scene reconstruction. Traditionally, this is achieved by measuring individual bloodstains and performing trigonometric calculations; however, 3D scanning has been proposed as a viable alternative for overcoming logistical and practical concerns with the manual method. Therefore, this project aimed to establish whether the FARO Focus 3D scanner and FARO Zone 3D software can improve the accuracy of area of origin estimates relative to the manual method. We created a series of eight bloodstain impact patterns and performed paired analysis using the two methods to estimate areas of origin for each pattern. Our data suggested that FARO-derived estimates were generally more accurate than using the manual method. FARO-estimated heights of origin areas were generally closer to the true distance. Both methods underestimated the distance from the wall for most patterns originating 150mm or greater from the wall, but overestimated distances for patterns originating closer to the wall. The degree to which distances were underestimated increased significantly the further the blood source was from the wall and was greater for FARO-derived estimates. The results of this research contribute to the validation of these instruments for operational implementation for BPA and should be considered alongside the practical benefits of 3D scanning relative to manual methods. Further, 3D scanning can provide reliable BPA reconstruction documentation for technical review and court presentation. 相似文献
143.
This article describes the current state and range of information protection in the growing number of states and Canadian provinces that employ parenting coordination in an effort to reduce repeat custody litigation. The predominant approach—in which what is revealed during the process is not confidential—is analyzed in terms of its compatibility with the parenting coordinator's multiple tasks of educating parents, seeking to facilitate agreements, and, if necessary, providing the court with a report, a recommended decision, or an arbitrated result. Using a case scenario with multiple parts, the article then examines such confidentiality schemes in practice by providing an action‐oriented series of questions that illustrate how much of this topic must be resolved through a parenting coordinator's exercise of discretion in the absence of rule clarity. The article then raises a number of policy questions about whether current parenting coordination confidentiality norms strike the optimal or even the correct balance on information protection and concludes by identifying several policy options that might address these questions. 相似文献
144.
Dorothy L. Espelage Kathleen C. Basile Ruth W. Leemis Tracy N. Hipp Jordan P. Davis 《Journal of youth and adolescence》2018,47(9):1880-1893
The Bully-Sexual Violence Pathway theory has indicated that bullying perpetration predicts sexual violence perpetration among males and females over time in middle school, and that homophobic name-calling perpetration moderates that association among males. In this study, the Bully-Sexual Violence Pathway theory was tested across early to late adolescence. Participants included 3549 students from four Midwestern middle schools and six high schools. Surveys were administered across six time points from Spring 2008 to Spring 2013. At baseline, the sample was 32.2% White, 46.2% African American, 5.4% Hispanic, and 10.2% other. The sample was 50.2% female. The findings reveal that late middle school homophobic name-calling perpetration increased the odds of perpetrating sexual violence in high school among early middle school bullying male and female perpetrators, while homophobic name-calling victimization decreased the odds of high school sexual violence perpetration among females. The prevention of bullying and homophobic name-calling in middle school may prevent later sexual violence perpetration. 相似文献
145.
Brian D. Christens Kymberly Byrd N. Andrew Peterson David T. LardierJr. 《Journal of youth and adolescence》2018,47(8):1649-1662
Psychological empowerment encompasses several key aspects of youth civic and sociopolitical development. Most research has focused on psychological empowerment’s emotional component, which entails learned hopefulness about one’s own ability to participate in and lead community change efforts. Fewer studies have assessed critical awareness of how social power operates—psychological empowerment’s cognitive component. The confluence of these two components has been termed critical hopefulness. A complex relationship exists between these two components, and previous research has found relatively small proportions of participants reporting both high levels of critical awareness and simultaneously high levels of hopefulness about their ability to exert influence in the sociopolitical domain. The current study of urban high school students in the Northeastern U.S. (n?=?389; 53.5% female) investigates heterogeneity according to these two components of psychological empowerment. Latent class cluster analyses were conducted and seven distinct groups of participants emerged. Students identifying as Hispanic/Latinx were more likely to be classified into a profile group exhibiting critical hopefulness. Differences were observed between psychological empowerment profile groups on self-reported levels of psychological sense of community, civic engagement, and social justice orientation. Furthermore, a larger proportion of this overall sample was classified into groups that exhibited critical hopefulness than in a previous study of adults. These findings provide useful insights for efforts to engage young people in civic life and to promote sociopolitical development. 相似文献
146.
The most common examination in sexual offences is the identification of spermatozoa in aqueous extracts from swabs. Using Proteinase K with sodium dodecyl sulphate, it is possible to digest all the cellular material apart from the spermatozoa, resulting in a quick and effective method of their isolation. Spermatozoa were detected in 18 extracts using this treatment when the normal method had failed to reveal all but one of them. 相似文献
147.
The eyes of fourteen fatally abused children and sixteen control cases were examined histopathologically. Ten of the abused children showed intraocular change. The most common ocular changes were subdural hemorrhage of the optic nerve and retinal hemorrhage which involved all the layers of the retina, but most commonly the nerve fiber layer, ganglion cell layer and inner nuclear layer. The presence of blood cavities within the retina partially supported the hypothesis of traumatic retinoschisis. The control cases of non-abused children rarely showed intraocular hemorrhage. 相似文献
148.
Katharine N. Rankin Andrea J. Nightingale Pushpa Hamal Tulasi S. Sigdel 《The Journal of peasant studies》2018,45(2):280-299
This paper explores the political field that has opened up in the wake of the recent civil war in Nepal. We focus on cultural-political developments in agrarian districts, where some of the most intriguing openings, and indeed the most pernicious closures, can be witnessed (as opposed to the national-state restructuring that commands more media and popular attention). Our research asks what spaces open up in the emerging political field at the district scale to entrench or transform dominant cultural codes and sedimented histories of socio-economic inequality. Preliminary research identifies specific sectors of local governance that have emerged as significant sites of struggle over the shape and meaning of ‘democracy’, namely forest management and infrastructure development. The primary contribution of the paper lies in specifying an analytical approach to the study of ‘post-conflict’ governance at the local scale via three conceptual terrains of inquiry – governance and planning, political subjectivity, and cultural politics. The ultimate objective is to develop a framework for assessing the conditions of possibility for a democratic restructuring of economy and society to accompany the official political institutions of liberal democracy. 相似文献
149.
Political Behavior - Americans are increasingly turning to social media for political information. However, given that the average social media user only clicks through on a small fraction of the... 相似文献
150.
South Africa, once a pariah state as a result of the apartheid regime destabilization policies in Southern Africa, became a full fledge democratic state following the victory of the African National Congress (ANC) in the first and all‐inclusive democratic elections of 1994. The ANC's vision for Southern Africa was to be routed on the notion of curbing the imbalances of the past (pre‐1994), which had cost the Southern African region great economic loss. Here, one of the many fundamentals that were to drive the ANC's foreign policy doctrine was that of conflict resolution for a more stable and prosperous Africa particularly Southern Africa. Conflict resolution was viewed as a pivotal element for the new democratic government in order to stimulate beneficial relations with other African states post the apartheid era. In light of the above, and using a qualitative method approach, this paper draws a nuanced appraisal and examines the role of South Africa's peacekeeping and mediation initiatives in the Democratic Republic of Congo (DRC) and Lesotho post‐1994. In conclusion, South Africa has been able to utilize its regional hegemonic stance to ensure regional security while ensuring economic stability at home. 相似文献