全文获取类型
收费全文 | 2905篇 |
免费 | 620篇 |
专业分类
各国政治 | 111篇 |
工人农民 | 19篇 |
世界政治 | 28篇 |
外交国际关系 | 139篇 |
法律 | 2165篇 |
中国共产党 | 17篇 |
中国政治 | 158篇 |
政治理论 | 582篇 |
综合类 | 306篇 |
出版年
2024年 | 6篇 |
2023年 | 21篇 |
2022年 | 26篇 |
2021年 | 66篇 |
2020年 | 101篇 |
2019年 | 201篇 |
2018年 | 170篇 |
2017年 | 161篇 |
2016年 | 179篇 |
2015年 | 164篇 |
2014年 | 209篇 |
2013年 | 403篇 |
2012年 | 298篇 |
2011年 | 244篇 |
2010年 | 194篇 |
2009年 | 164篇 |
2008年 | 176篇 |
2007年 | 188篇 |
2006年 | 140篇 |
2005年 | 75篇 |
2004年 | 75篇 |
2003年 | 87篇 |
2002年 | 57篇 |
2001年 | 39篇 |
2000年 | 17篇 |
1999年 | 9篇 |
1998年 | 10篇 |
1997年 | 2篇 |
1996年 | 5篇 |
1995年 | 2篇 |
1994年 | 7篇 |
1993年 | 2篇 |
1992年 | 3篇 |
1991年 | 5篇 |
1990年 | 4篇 |
1989年 | 4篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1983年 | 2篇 |
排序方式: 共有3525条查询结果,搜索用时 15 毫秒
61.
Accurate age estimates of immature necrophagous insects associated with a human or animal body can provide evidence of how long the body has been dead. These estimates are based on species-specific details of the insects’ aging processes, and therefore require accurate species identification and developmental stage estimation. Many professionals who produce or use identified organisms as forensic evidence have little training in taxonomy or metrology, and appreciate the availability of formalized principles and standards for biological identification. Taxonomic identifications are usually most readily and economically made using categorical and qualitative morphological characters, but it may be necessary to use less convenient and potentially more ambiguous characters that are continuous and quantitative if two candidate species are closely related, or if identifying developmental stages within a species. Characters should be selected by criteria such as taxonomic specificity and metrological repeatability and relative error. We propose such a hierarchical framework, critique various measurements of immature insects, and suggest some standard approaches to determine the reliability of organismal identifications and measurements in estimating postmortem intervals. Relevant criteria for good characters include high repeatability (including low scope for ambiguity or parallax effects), pronounced discreteness, and small relative error in measurements. These same principles apply to individuation of unique objects in general.
Key points
- Metrological rigour can increase in forensic entomology by selecting measurements based on their metrological qualities.
- Selection of high-quality features for morphological identification of organisms should consider these criteria: (1) pronounced discreteness of features (minimising group overlap or maximizing interval); (2) high repeatability of assessment (such as symmetrical width rather than asymmetrical length); (3) small relative error in measurement (selecting the physically largest continuous rigid feature for measurement).
- These metrological principles also apply to individuation of unique objects in general.
62.
A plethora of literature has been undertaken to study the validity of the Feldstein–Horioka (FH) puzzle. However, divergent views continue to persist in the FH puzzle literature. This study explores the empirical validity of the FH puzzle in the case of South Asian countries using annual data from 1960 to 2017. Both panel data approach and Markov‐switching regression approach are used to empirically analyze the FH puzzle. The results of the cointegration test confirm the long‐run relationships between saving and investment in the selected South Asian countries. The results of Markov‐switching regression confirm that the saving‐retention coefficient has shifted from high to low values and also from low to high values. Thus, the FH puzzle exists for a particular time period and mostly depends on the regime shifts in the South Asian countries. The results of panel fully modified ordinary least squares (FMOLS) and dynamic ordinary least squares (DOLS) methods also confirm that FH puzzle holds for the South Asian countries. Therefore, the study suggests that any saving promotion policies are desirable for enhancing investment among the South Asian regions. 相似文献
63.
Gonzalo Ordez‐Matamoros Michelle Vernot‐Lpez Ornella Moreno‐Mattar Luis Antonio Orozco 《政策研究评论》2020,37(2):174-200
International research collaboration (IRC) is associated with both positive and negative effects on the performance of research in emerging economies. While some authors claim that North–South collaborations improve scientific quality and visibility for Southern countries, others claim that it may entail the reorientation of research to comply with Northern agendas. South–South collaborations are thought to increase the focus on local affairs, therefore leading to a relatively small number of scientific international publications appearing in “high quality” journals. Research on the impact of IRC beyond publications in international journals has been neglected despite the importance of other products in knowledge creation. This research uses a broad range of scientific outputs to empirically assess such assumptions and explore the outcomes of IRC in Colombia. Results from multivariate regressions and nonparametric analyses show that, contrary to common assumptions, Colombian research teams collaborating with partners from the global South report higher scientific production, while those collaborating with Northern countries seem to contribute to local knowledge the most. 相似文献
64.
Scholars and practitioners have repeatedly questioned the democraticness and the authority of transnational multi‐stakeholder organizations, especially those that regulate the internet. To contribute to this discussion, we studied the “democratic anchorages” and the regulatory authority of 23 internet regulators. In particular, we conducted a fuzzy‐set qualitative comparative analysis assessing whether and which anchorages correspond to necessary and/or sufficient conditions for exerting regulatory authority. Our results show that strong anchorage in democratic procedures is specifically relevant for this outcome. Further, we find that weak anchorage in democratically elected politicians leads to high regulatory authority, confirming the significance of non‐state actors in this policy field. More generally, our findings support but also qualify expectations about the compatibility and mutual reinforcement of democratic quality and regulatory authority at the transnational level. 相似文献
65.
Richard A. Warshak 《Family Court Review》2020,58(2):432-455
Involvement in custody cases that include accusations of parental alienation—whether as an evaluator, expert witness, lawyer, judge, therapist, provider of a specialized intervention, or researcher—incurs both professional and personal risks. Some risks relate to false negative or false positive identifications of parental alienation that can lead to regulatory agency complaints and public condemnation by the parent who feels wronged by the case outcome. Other risks stem from providing services in an emerging area of practice and working with children who overtly oppose repairing the relationship with their rejected parent. These risks include: unfounded accusations of mistreating children; negatively biased commentary and sensationalist attacks in the media and in social media, professional conferences and journals, and in courtroom testimony; harassment, vilification, and invasion of privacy; threats of violence and public humiliation; shunning and rumor spreading by colleagues; and complaints to regulatory agencies. This article examines circumstances, beliefs, and dynamics that give rise to these risks, suggests precautions to reduce the risk of false accusations against professionals, and offers recommendations for dealing with regulatory agencies. Criticisms that a court or service provider has mistreated a child merit careful scrutiny in the context of the case evidence and empirical data. While some interventions for alienated children raise legitimate concerns, others have been maligned by anecdotal complaints that studies show do not represent the experience of most participants. 相似文献
66.
67.
68.
Trishawn Raffington 《Family Court Review》2020,58(1):243-257
The current administration's zero tolerance stance on illegal immigration has resulted in the separation of thousands of families and the de facto termination of parental rights. While undocumented parents were always at risk of detainment, expanded immigration enforcement under the Trump administration has greatly increased that risk. Detainment has directly and indirectly resulted in the prolonged separation of parents from their children. This Note proposes a Department of Homeland Security Regulation that will require ICE to use the least restrictive methods to achieve its goals while emphasizing efforts to keep families together. 相似文献
69.
70.
Mária Kondeková Radoslav Beňuš Ph.D. Soňa Masnicová Ph.D. Petra Švábová Ph.D. 《Journal of forensic sciences》2020,65(4):1303-1309
Minutiae are small distinguishing features found along every ridge flow, which make each friction ridge print unique. The most common friction ridge prints found at the crime scene are fingerprints; therefore, the most of the minutiae studies are focused exactly on this kind of prints. The authors believe that further examination and enlargement of the palm print database could result in better use of the palm prints for personal identification. We analyzed a total of 160 palm prints from 40 females and 40 males aged between 18 and 70 years from Slovakia. For the evaluation of the minutiae, the area of the hypothenar had to be marked out. The classification of the minutiae used for this study was based on a modified version of the classification system using the total of 13 types of minutiae. The frequency of every minutiae type was calculated and, using the chi-square test with Yates's correction, bilateral and sex differences were assessed. The relationship between the different types of minutiae was examined with Pearson's correlation test. During the initial phases of the identification process, the focus should be on the least common types of minutiae (Y or M and return), which were found not to correlate; thus, their mutual occurrence is random (e.g., overlap—Y or M, crossbar—return, or Y or M—dock). The results of the present study show which specific minutiae types are the most suitable for personal identification. These findings may be beneficial in more effective outcome of the identification process. 相似文献