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941.
Forensic anthropological examinations typically involve the analysis of human skeletal remains, but in cases where samples are very small and/or physically compromised, it may first be necessary to determine whether the material is even osseous or dental in origin. X-ray fluorescence spectrometry (XRF) is a technique that reveals the elemental composition of materials and is hypothesized to have utility in such cases. XRF analysis was conducted on a variety of tissues and materials in unaltered and altered (damaged) states. With few exceptions, osseous and dental tissues in unaltered and altered conditions contained characteristic levels of calcium and phosphorus, while other materials did not. Materials could be accurately identified as osseous or dental in origin based on the calcium and phosphorus levels identified by XRF, and we therefore conclude that XRF analysis is a valid and effective means of determining osseous or dental origin of unknown material.  相似文献   
942.
《Justice Quarterly》2012,29(1):132-162
Problem‐oriented policing has been suggested as a promising way to understand and prevent complex gang violence problems. A number of jurisdictions have been experimenting with new problem‐oriented frameworks to understand and respond to gun violence among gang‐involved offenders. These interventions are based on the “pulling levers” deterrence strategy that focuses criminal justice and social service attention on a small number of chronically offending gang members responsible for the bulk of urban gun violence problems. As part of the US Department of Justice‐sponsored Project Safe Neighborhoods initiative, an interagency task force implemented a pulling levers strategy to prevent gang‐related gun violence in Lowell, Massachusetts. Our impact evaluation suggests that the pulling levers strategy was associated with a statistically significant decrease in the monthly number of gun homicide and gun‐aggravated assault incidents. A comparative analysis of gun homicide and gun‐aggravated assault trends in Lowell relative to other major Massachusetts cities also supports a unique program effect associated with the pulling levers intervention.  相似文献   
943.
《Justice Quarterly》2012,29(4):827-854

This article examines the relationship between racial discrimination and delinquency. Using longitudinal data collected on approximately 700 African American children, we begin by establishing an association between exposure to discrimination and delinquent behavior. Next, we use structural equation modeling to test various hypotheses regarding the emotional and cognitive factors that mediate this association. For boys, the association between discrimination and delinquency is mediated by feelings of anger and depression and by the belief that aggression is a necessary interpersonal tactic. The results are somewhat different for girls. Although anger and depression mediate part of the effect of discrimination on delinquency, discrimination continues to display a small but significant direct effect. The implications of these findings for criminological theory are discussed.  相似文献   
944.
Powder X-ray diffraction (PXRD) is used widely in forensic science laboratories with the main focus of qualitative phase identification. Little is found in literature referring to the topic of validation of PXRD in the field of forensic sciences. According to EN ISO/IEC 17025, the method has to be tested for several parameters. Trueness, specificity, and selectivity of PXRD were tested using certified reference materials or a combination thereof. All three tested parameters showed the secure performance of the method. Sample preparation errors were simulated to evaluate the robustness of the method. These errors were either easily detected by the operator or nonsignificant for phase identification. In case of the detection limit, a statistical evaluation of the signal-to-noise ratio showed that a peak criterion of three sigma is inadequate and recommendations for a more realistic peak criterion are given. Finally, the results of an international proficiency test showed the secure performance of PXRD.  相似文献   
945.
Abstract: Three classic cases and one exceptional case are reported. The unique case of decapitation took place in a traffic accident, while the others were seen after homicide, vehicle‐assisted suicide, and after long‐jump hanging. Thorough scene examinations were performed, and photographs from the scene were available in all cases. Through the autopsy of each case, the mechanism for the decapitation in each case was revealed. The severance lines were through the neck and the cervical vertebral column, except for in the motor vehicle accident case, where the base of skull was fractured. This case was also unusual as the mechanism was blunt force. In the homicide case, the mechanism was the use of a knife combined with a saw, while in the two last cases, a ligature made the cut through the neck. The different mechanisms in these decapitations are suggested.  相似文献   
946.
Normally, the identification of the LSD drug is performed by forensic laboratories, using the Ehrlich spot test. However, this is a nonspecific analysis. Additionally, the Brazilian Federal Police has identified the presence of a new compound in seized blotters: 9,10-dihydro-LSD, an uncontrolled substance. In this work, easy ambient sonic-spray ionization mass spectrometry in the positive ion mode, EASI(+)-MS, was used to characterize LSD and 9,10-dihydro-LSD compositions directly from the surface of blotters. The presence of LSD in the seized blotter samples were also confirmed via high-performance liquid chromatography with ultraviolet detector. In a set of 41 blotters analyzed by EASI(+)-MS, 28 showed positive results for LSD, seven for 9,10-dihydro-LSD, and another six samples showed negative results for both LSD and 9,10-dihydro-LSD. The combination of thin layer chromatography with EASI-MS also demonstrated to be a relatively simple and powerful screening tool for forensic analysis of street drugs.  相似文献   
947.
Abstract: In this study, the specificity, sensitivity, and operability of RSID?‐Urine, a new immunochromatographic test for urine identification, was evaluated and compared with ELISA detection of Tamm‐Horsfall protein (THP). Urine was successfully identified among other body fluids using RSID?‐Urine and ELISA detection of THP. The detection limit of RSID?‐Urine equated to 0.5 μL of urine; although the sensitivity of RSID?‐Urine may be lower than that of ELISA detection of THP, it is thought to be sufficient for application to casework samples. However, results from RSID?‐Urine must be interpreted with caution when the sample may have been contaminated with blood or vaginal fluid, because this might inhibit urine detection. The RSID?‐Urine assay can be performed in just 15 min by dropping the extracted sample onto the test cassette. Therefore, RSID?‐Urine should be an effective tool for the forensic identification of urine, in addition to ELISA detection of THP.  相似文献   
948.
Abstract: In the course of the validation of a new component of the prostate‐specific antigen (PSA) SemiQuant Cassette Test marketed by Seratec®, a false‐positive reaction was observed when testing samples collected from the surface of unused, lubricated condoms. A variety of personal lubricants and condoms were tested to determine the frequency of the false positive, as well as its potential source. Samples were extracted in both water and the manufacturer‐provided buffer, and the test was performed according to the manufacturer’s suggested protocol. The false positive was observed intermittently, but occurred consistently with samples containing nonoxynol‐9, a strong detergent utilized as a spermicide. The reaction may be attributable to the combination of latex and nonoxynol‐9. Because of the unreliability of the test to confirm the presence of PSA in samples collected from condoms, the PSA cassette is an unsuitable method for confirming the presence of seminal fluid in condoms.  相似文献   
949.
This paper uses new research into the derivatives markets to develop our understanding of standard form contracts as transnational law and to show how transnational law theory may be usefully informed by empirical work. Traditionally, it has been assumed that international business communities seek to avoid the courts. However, the paper shows that the national courts play a prominent role in adjudicating disputes involving derivatives. Basing the discussion on the detail of these decisions by the English courts, the paper demonstrates that adjudication does not necessarily undermine widely used standard form contracts, and that it may even reinforce practices that underpin them. This is particularly the case where there is imperfect co‐incidence between a trade association's members and a standard form contract's users. Having explored recent cases, the paper reconciles its findings with a more open and imaginative account of the role of national courts within transnational law theory.  相似文献   
950.
《Justice Quarterly》2012,29(3):309-346
Although intimate partner abuse has been extensively researched over the last thirty years, battered women’s help‐seeking remains perplexingly undertheorized, particularly within criminology. This analysis aims to offer a corrective by applying the feminist pathways theoretical model—which examines women’s and girls’ offending behaviors in the context of their past victimization experiences—to battered women’s help‐seeking. Data from in‐depth life history interviews with 22 battered women in two states indicate that the women’s childhood victimization experiences informed their adult help‐seeking decisions in meaningful ways. The primary theoretical contribution of this analysis is the identification of specific mechanisms—five help‐seeking inhibitors and three help‐seeking promoters—through which childhood victimization influenced participants’ help‐seeking. Results of this analysis demonstrate the benefit of a feminist pathways theoretical model of battered women’s help‐seeking in order to better understand how pathways of victimization and resistance develop over the course of women’s lives.  相似文献   
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