全文获取类型
收费全文 | 381篇 |
免费 | 15篇 |
专业分类
各国政治 | 15篇 |
工人农民 | 10篇 |
世界政治 | 34篇 |
外交国际关系 | 23篇 |
法律 | 179篇 |
中国政治 | 1篇 |
政治理论 | 127篇 |
综合类 | 7篇 |
出版年
2023年 | 2篇 |
2022年 | 4篇 |
2021年 | 4篇 |
2020年 | 5篇 |
2019年 | 7篇 |
2018年 | 14篇 |
2017年 | 12篇 |
2016年 | 11篇 |
2015年 | 7篇 |
2014年 | 10篇 |
2013年 | 65篇 |
2012年 | 7篇 |
2011年 | 4篇 |
2010年 | 12篇 |
2009年 | 7篇 |
2008年 | 10篇 |
2007年 | 12篇 |
2006年 | 15篇 |
2005年 | 9篇 |
2004年 | 13篇 |
2003年 | 9篇 |
2002年 | 16篇 |
2001年 | 6篇 |
2000年 | 3篇 |
1999年 | 5篇 |
1998年 | 6篇 |
1997年 | 9篇 |
1996年 | 10篇 |
1995年 | 2篇 |
1994年 | 6篇 |
1993年 | 4篇 |
1992年 | 4篇 |
1991年 | 7篇 |
1990年 | 5篇 |
1989年 | 7篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 3篇 |
1985年 | 8篇 |
1984年 | 6篇 |
1983年 | 6篇 |
1982年 | 7篇 |
1981年 | 6篇 |
1978年 | 6篇 |
1976年 | 3篇 |
1975年 | 6篇 |
1974年 | 2篇 |
1973年 | 4篇 |
1970年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有396条查询结果,搜索用时 0 毫秒
341.
Latent Fingermark Aging Patterns (Part III): Discontinuity Index as One Indicator of Degradation 下载免费PDF全文
Josep De Alcaraz‐Fossoul Ph.D. Carme Barrot Feixat Ph.D. Clara Carreras‐Marin M.Sc. Jack Tasker B.Sc. Sara C. Zapico Ph.D. Manel Gené Badia Ph.D. 《Journal of forensic sciences》2017,62(5):1180-1187
This article is the third in a series of reports exploring quantifiable visual parameters of the aging process of latent fingermarks. On this occasion, research is focused on the occurrence of ridge discontinuities (i.e. breakages) as a function of time. Experiment variables included type of secretion (eccrine and sebaceous), substrate (glass and plastic), and exposure to natural light (dark, shade, and direct light) over a 6 months period. Fingermarks were sequentially visualized with titanium dioxide powder, photographed, and the number of naturally occurring ridge discontinuities subsequently evaluated. A semi‐quantitative value, named Discontinuity Index, was used to better characterize this aging parameter. Results indicated that ridges of sebaceous depositions on glass were generally less affected by the environmental conditions compared with those on plastic surface. In addition, aging in darkness was not always the best condition for preservation, and the direct exposure to light seemed not to affect the degradation under certain conditions. 相似文献
342.
David Terburg Barak Morgan Jack van Honk 《International journal of law and psychiatry》2009,32(4):216-223
Social aggression is an escalating hazard for individuals and society. It is most frequently observed as impulsive–reactive aggression in antisocial personality disorder (APD), but in psychopathic aggressive personalities instrumental social aggression is more prominent. However, the psychobiological mechanisms underlying human social aggression are still poorly understood. Here we propose a psychobiological mechanism that may explain human social aggression wherein the steroid hormones cortisol and testosterone play a critical role. High levels of testosterone and low levels of cortisol have been associated with social aggression in several species but it seems that in those individuals wherein these hormonal markers combine social aggression is most violent. In this review we discuss fundamental and clinical research which underscores the potential of the testosterone–cortisol ratio as a possible marker for criminal aggressive tendencies. 相似文献
343.
Josep De Alcaraz‐Fossoul Ph.D. Carme Barrot‐Feixat Ph.D. Sara C. Zapico Ph.D. Michelle Mancenido Ph.D. Jennifer Broatch Ph.D. Katherine A. Roberts Ph.D. Clara Carreras‐Marin M.Sc. Jack Tasker B.Sc. 《Journal of forensic sciences》2018,63(4):1085-1091
A methodology to estimate the time of latent fingerprint deposition would be of great value to law enforcement and courts. It has been observed that ridge topography changes as latent prints age, including the widths of ridges that could be measured as a function of time. Crime suspects are commonly identified using fingerprint databases that contain reference inked tenprints (flat and rolled impressions). These can be of interest in aging studies as they provide baseline information relating to the original (nonaged) ridges’ widths. In practice, the age of latent fingerprints could be estimated following a comparison process between the evidentiary aged print and the corresponding reference inked print. The present article explores possible correlations between inked and fresh latent fingerprints deposited on different substrates and visualized with TiO2. The results indicate that the ridge width of flat inked prints is most similar to fresh latent fingerprints, and these should be used as the comparison standard for future aging studies. 相似文献
344.
This paper aims to contribute (1) to the understanding about how small technology-based firms in spite of being constrained by limited resources, can still perform exploratory and exploitative innovation and (2) to extend knowledge about the role of slack resources in the context of small technology-based firms in facilitating those innovation activities. Herein, we focus on two types of slack resources: internal slack, resources that are available within the firms and external slack, additional resources that are gathered through the facilitation of external sources such as business incubators. Using a sample of 141 small technology-based firms located at incubators, this study combined two streams of research on incubator studies and innovation to construct some hypotheses examining the role of slack resources and innovation activities in enhancing the performance of small technology-based firms operating in incubator setting. Our findings demonstrate that neither slack resources nor innovation activities alone explain firm performance. Instead, small technology-based firms fit their innovation activities to their slack resources. While the relationship between internal slack and performance is mediated by exploitative innovation, exploratory innovation plays a role as a mediator for the relationship between external slack and performance. 相似文献
345.
Entrepreneurship and Legal Uncertainty: Unexpected Federal Trademark Registrations for Marijuana Derivatives 下载免费PDF全文
Though several states have legalized marijuana use, the drug remains illegal under federal law. Not surprisingly, the United States Patent and Trademark Office (USPTO) refuses to register trademarks related to marijuana because of the federal prohibition. What is surprising, though, is the willingness to grant trademarks for cannabidiol (CBD), a marijuana derivative that is likewise expressly illegal under federal drug laws. This article explains why the USPTO's divergent treatment of trademark applications for CBD and marijuana products is legally incoherent. Additionally, when viewed from an entrepreneurial perspective, this phenomenon exemplifies how legal uncertainty breeds entrepreneurial opportunity. Specifically, the article argues that the evolving regulatory landscape for CBD and marijuana products has been and continues to be ripe for legal strategists and innovative entrepreneurs to combine forces to create competitive advantage in the emerging marijuana industry. 相似文献
346.
347.
Depending upon specific situations, some victims of sexual assault provide vaginal samples more than 36-48 h after the incident. We have tested the ability of commercial and in-house Y-STR systems to provide DNA profiles from extended interval (> or =3 days) postcoital samples. The commercial Y-STR systems tested included the AmpFlSTR Yfiler (Applied Biosystems), PowerPlex Y (Promega) and Y-PLEX 12 (Reliagene) products whereas the in-house systems comprised Multiplex I (MPI) and Multiplex B (MPB). Three donor couples were recruited for the study. Postcoital cervicovaginal swabs (x2) were recovered by each of the three females at specified intervals after sexual intercourse (3-7 days). Each time point sample was collected after a separate act of sexual intercourse and was preceded by a 7-day abstention period. As a negative control, a precoital swab was also recovered prior to coitus for each sampling and only data from postcoital samples that demonstrated a lack of male DNA in the associated precoital sample was used. A number of DNA profile enhancement strategies were employed including sampling by cervical brushing, nondifferential DNA extraction methodology, and post-PCR purification. Full Y-STR profiles from cervicovaginal samples recovered 3-4 days after intercourse were routinely obtained. Profiles were also obtainable 5-6 days postcoitus although by this stage partial profiles rather than full profiles were a more likely outcome. The DNA profiles from the sperm fraction of a differential lysis were superior to that obtained when a nondifferential method was employed in that the allelic signal intensities were generally higher and more balanced and exhibited less baseline noise. The incorporation of a simple post-PCR purification process significantly increased the ability to obtain Y-STR profiles, particularly from 5- to 6-day postcoital samples. Remarkably an 8 locus Y-STR profile was obtained from a 7-day postcoital sample, which is approaching the reported time limit for sperm detection in the cervix. 相似文献
348.
Jack R. Greene 《Journal of criminal justice》1986,14(6)
The article reports a portion of the findings of a national study of manpower planning in criminal justice. The study and its findings have been reported more fully elsewhere. The present article reexamines and reconsiders the data specifically with respect to public policymaking, the behavior of public organizations, and the role of fact and value in the allocation of government resources. 相似文献
349.
Karim M. Abdel‐Hay Ph.D. Jack DeRuiter Ph.D. C. Randall Clark Ph.D. 《Journal of forensic sciences》2015,60(2):285-294
A number of N‐substituted piperazines have been described as drugs of abuse in recent years. This new drug category includes several series of aromatic ring substituted phenylpiperazines. The wide variety of available precursors makes regioisomerism a significant issue in these totally synthetic compounds. In this study, a complete series of regioisomeric dimethoxyphenylpiperazines were synthesized and evaluated using GC‐MS and FT‐IR. The EI mass spectra show fragments characteristic of both the dimethoxyphenyl and the piperazine portions of the molecules including the dimethoxyphenylaziridinium cation (m/z 180) and dimethoxyphenyl cation (m/z 137). The ion at m/z 56 for the C3H6N+ fragment is characteristic of the piperazine ring and was observed in all the spectra. The perfluoroacyl derivatives were resolved by GC, and their mass spectra showed some differences in relative abundance of ions. FTIR provides direct confirmatory data for differentiation between the regioisomeric dimethoxyphenylpiperazines, and GC separation was accomplished on an Rtx‐200 phase. 相似文献
350.
This article interrogates three key arguments derived from the functional approach to studying the core executive: (1) that coordination is the primary problem that confronts executive decision‐makers; (2) that improved coordination will lead to better governance; and (3) that linkage problems dissipate as policy systems consolidate. Drawing on the experience of hitherto understudied small states, including 112 interviews with political elites, we show how the effects of country size create governance challenges in the form of leader dominance, patronage systems and capacity constraints. Our findings support the call to broaden the focus of functional analysis beyond its traditional emphasis on coordination. For scholars of small states we synthesize existing empirical findings and provide a theoretical justification for future work using an adaptation of the core executive approach. 相似文献