全文获取类型
收费全文 | 553篇 |
免费 | 32篇 |
专业分类
各国政治 | 18篇 |
工人农民 | 53篇 |
世界政治 | 71篇 |
外交国际关系 | 25篇 |
法律 | 292篇 |
中国政治 | 3篇 |
政治理论 | 120篇 |
综合类 | 3篇 |
出版年
2024年 | 1篇 |
2023年 | 9篇 |
2022年 | 4篇 |
2021年 | 8篇 |
2020年 | 18篇 |
2019年 | 22篇 |
2018年 | 33篇 |
2017年 | 25篇 |
2016年 | 28篇 |
2015年 | 23篇 |
2014年 | 13篇 |
2013年 | 76篇 |
2012年 | 24篇 |
2011年 | 15篇 |
2010年 | 15篇 |
2009年 | 31篇 |
2008年 | 15篇 |
2007年 | 14篇 |
2006年 | 15篇 |
2005年 | 25篇 |
2004年 | 16篇 |
2003年 | 23篇 |
2002年 | 18篇 |
2001年 | 17篇 |
2000年 | 14篇 |
1999年 | 9篇 |
1998年 | 2篇 |
1997年 | 7篇 |
1996年 | 2篇 |
1995年 | 6篇 |
1994年 | 5篇 |
1993年 | 6篇 |
1992年 | 4篇 |
1991年 | 4篇 |
1990年 | 2篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 5篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1977年 | 3篇 |
1975年 | 2篇 |
1973年 | 2篇 |
排序方式: 共有585条查询结果,搜索用时 15 毫秒
351.
Research Summary
This article discusses the paucity of data available for assessing the "life span" of a terrorist group. It introduces a new methodology that allows researchers to examine when terrorist groups perform their preincident activities. The findings suggest that differences exist in the temporal patterns of terrorist groups: environmental terrorist groups engage in a relatively short planning cycle compared with right-wing and international terrorists. The article concludes by examining a case study on "the Family," which is a unique environmental terrorist group that conducted activities over a relatively long period of time. This group provides an interesting contrast to other environmental terrorists. Despite significant organizational differences, their patterns of preparatory conduct were highly similar.
Policy Implications
The findings suggest that (1) temporal and spatial data about preincident terrorist activity can be collected from unclassified and open sources and (2) law-enforcement agencies that are investigating environmental groups have relatively little time to observe and infiltrate their individual cells (compared with right-wing and international terrorists). Finally, the data suggest that environmental terrorists—at least so far—have engaged in attacks that are less deadly than the comparison groups. 相似文献
This article discusses the paucity of data available for assessing the "life span" of a terrorist group. It introduces a new methodology that allows researchers to examine when terrorist groups perform their preincident activities. The findings suggest that differences exist in the temporal patterns of terrorist groups: environmental terrorist groups engage in a relatively short planning cycle compared with right-wing and international terrorists. The article concludes by examining a case study on "the Family," which is a unique environmental terrorist group that conducted activities over a relatively long period of time. This group provides an interesting contrast to other environmental terrorists. Despite significant organizational differences, their patterns of preparatory conduct were highly similar.
Policy Implications
The findings suggest that (1) temporal and spatial data about preincident terrorist activity can be collected from unclassified and open sources and (2) law-enforcement agencies that are investigating environmental groups have relatively little time to observe and infiltrate their individual cells (compared with right-wing and international terrorists). Finally, the data suggest that environmental terrorists—at least so far—have engaged in attacks that are less deadly than the comparison groups. 相似文献
352.
Child custody evaluations need to be studied systemically as a human service system. There is little research on the history, caseload dynamics, economics, delivery systems, or impact of custody evaluations. This article identifies five systems‐level questions about custody evaluations and examines one, outcomes assessment, in detail by developing seven outcome hypotheses. The article concludes that such research could improve the practice and use of child custody evaluations. 相似文献
353.
Raman spectroscopy was used to compare body fluids commonly found at crime scenes in a nondestructive manner. The dry traces of semen, vaginal fluid, sweat, saliva, and blood were analyzed using confocal Raman microscopy with a 785-nm excitation. The results show that the five fluids can be differentiated from one another by visual comparison of their Raman spectra, and that the laser radiation does not damage the sample. The Raman signature of each body fluid is specific and correlates with the known composition of the fluid. Dry traces of human and canine semen exhibited distinctly different Raman signatures. Overall, this preliminary study demonstrates the great potential of Raman spectroscopy for nondestructive, confirmatory identification of body fluids for forensic purposes. 相似文献
354.
Kelly E. Carter B.A. Macgregor D. Vogelsang B.S. John Vanderkolk B.A. Thomas Busey Ph.D. 《Journal of forensic sciences》2020,65(4):1141-1154
During fingerprint comparisons, a latent print examiner visually compares two impressions to determine whether or not they originated from the same source. They consider the amount of perceived detail in agreement or disagreement and accumulate evidence toward same source and different sources propositions. This evidence is then mapped to one of three conclusions: Identification, Inconclusive, or Exclusion. A limitation of this 3-conclusion scale is it can lose information when translating the conclusion from the internal strength-of-evidence value to one of only three possible conclusions. An alternative scale with two additional values, support for different sources and support for common sources, has been proposed by the Friction Ridge Subcommittee of OSAC. The expanded scale could lead to more investigative leads but could produce complex trade-offs in both correct and erroneous identifications. The aim of the present study was to determine the consequences of a shift to expanded conclusion scales in latent print comparisons. Latent print examiners each completed 60 comparisons using one of the two scales, and the resulting data were modeled using signal detection theory to measure whether the expanded scale changed the threshold for an “Identification” conclusion. When using the expanded scale, examiners became more risk-averse when making “Identification” decisions and tended to transition both the weaker Identification and stronger Inconclusive responses to the “Support for Common Source” statement. The results demonstrate the utility of an expanded conclusion scale and also provide guidance for the adoption of these or similar scales. 相似文献
355.
Kelly P. Kearse Ph.D. 《Journal of forensic sciences》2020,65(5):1716-1721
The use of alternative light sources (ALS) in bloodstain analysis has focused on dried (whole) blood, while information on detection of blood serum is lacking. Serum detection by ALS could provide valuable information at a crime scene, as serum may become separated from blood during clotting and cast off, especially in cases where the victim is moved. Additionally, a perpetrator may concentrate on the removal/scouring of dried blood with small amounts of serum going unnoticed, as it dries relatively clear on certain objects. In this report, the detection of human blood serum was evaluated using ultraviolet (UV) light at two different wavelengths. These results show that ultraviolet (UV) at 365 nm (UV365) was effective in the detection of even small amounts of blood plasma and serum, compared with UV at 395 nm, which was not. UV365 was also found to be useful in distinguishing blood imprints from clotting blood which had been transferred to material versus blood that had been added directly. Taken together, these results demonstrate that UV365 may be utilized as a simple, nondestructive method for blood serum detection. 相似文献
356.
With the adoption of statutes, policies and administrative guidance since the late 1980s, statutory child welfare agencies around the world have been implementing practice approaches to resolving and addressing child abuse and neglect concerns that involve extended family systems in decision making and planning. One such approach is the family group conference (FGC), enshrined in New Zealand law. This article provides a historical context and describes numerous provisions of the family group conference that protect participants and the proceedings. It then describes applications of FGC‐like approaches in the United States where practice models and policies—not laws—guide the implementation of such approaches. 相似文献
357.
358.
Mitragyna speciosa (MS), a plant commonly known as kratom, is a widely used “legal high” opiate alternative for pain relief. DNA extracted from MS and 26 additional plant species was amplified by PCR using primers targeting the strictosidine beta-D-glucosidase (SGD) and secologanin synthase 2 (SLS2) genes and detected by high-resolution melt curves using three intercalating dyes. Amplicon sizes were confirmed using agarose gel electrophoresis. The observed melt temperatures for SGD and SLS2 were 77.08 ± 0.38°C and 77.61 ± 0.46°C, respectively, using SYBR® Green I; 80.18 ± 0.27°C and 80.59 ± 0.08°C, respectively, using Radiant™ Green; and 82.19 ± 0.04°C and 82.62 ± 0.13°C, respectively, using the LCGreen® PLUS dye. The SLS2 primers demonstrated higher specificity and identified MS DNA at 0.05 ng/μL. In a duplex reaction, SLS2 and tetrahydrocannabinoic acid synthase gene primers detected and differentiated MS and Cannabis sativa (CS) by melt peaks at 82.63 ± 0.35°C and 85.58 ± 0.23°C, respectively, using LCGreen® PLUS. 相似文献
359.
Angelique L. Ryan B.S. Cassandra P. O’Hern B.S. Kelly M. Elkins Ph.D. 《Journal of forensic sciences》2020,65(5):1704-1708
A quick, simple, and high-yield nucleic acid isolation process is crucial for high-quality DNA analysis. The ability of the MicroGEM PDQeX phytoGEM system and Omega Bio-tek E.Z.N.A.® Plant DS Mini kit to extract PCR-ready DNA was evaluated by extracting the forensically relevant “legal high” plant species: Ipomoea purpurea, Artemisia absinthium, Mitragyna speciosa, Datura stramonium, and Papaver somniferum. The plant material was pulverized, processed using the manufacturer’s plant protocol for the PDQeX Nucleic Acid Extraction or the manufacturer’s protocol for the Omega extraction, quantified using the Invitrogen Qubit 2.0 Fluorometer, and analyzed for amplifiability by PCR using a Qiagen Rotor-Gene Q instrument and published assays. The DNA amplicons for the legal high species produced high-resolution melt curves concordant with the melts observed when DNA was isolated using the Qiagen DNeasy Plant Mini Kit in previous studies. 相似文献
360.
Mulvey Kelly Lynn Gönültaş Seçil Goff Eric Irdam Greysi Carlson Ryan DiStefano Christine Irvin Matthew J. 《Journal of youth and adolescence》2019,48(3):581-596
Journal of Youth and Adolescence - Youth aggression occurs at high rates. Aggressive acts can be curbed through bystander intervention; yet, little is known about school and family factors that... 相似文献