全文获取类型
收费全文 | 812篇 |
免费 | 39篇 |
专业分类
各国政治 | 51篇 |
工人农民 | 133篇 |
世界政治 | 59篇 |
外交国际关系 | 37篇 |
法律 | 399篇 |
中国政治 | 8篇 |
政治理论 | 160篇 |
综合类 | 4篇 |
出版年
2023年 | 4篇 |
2022年 | 9篇 |
2021年 | 16篇 |
2020年 | 29篇 |
2019年 | 40篇 |
2018年 | 48篇 |
2017年 | 52篇 |
2016年 | 53篇 |
2015年 | 26篇 |
2014年 | 31篇 |
2013年 | 145篇 |
2012年 | 40篇 |
2011年 | 35篇 |
2010年 | 18篇 |
2009年 | 28篇 |
2008年 | 32篇 |
2007年 | 35篇 |
2006年 | 17篇 |
2005年 | 27篇 |
2004年 | 17篇 |
2003年 | 21篇 |
2002年 | 31篇 |
2001年 | 12篇 |
2000年 | 8篇 |
1999年 | 9篇 |
1998年 | 5篇 |
1997年 | 5篇 |
1996年 | 9篇 |
1995年 | 10篇 |
1994年 | 1篇 |
1993年 | 7篇 |
1992年 | 6篇 |
1991年 | 1篇 |
1990年 | 4篇 |
1989年 | 1篇 |
1988年 | 4篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
排序方式: 共有851条查询结果,搜索用时 31 毫秒
231.
A reference standard for gamma-hydroxybutyric acid (GHB) free acid is not commercially available, making its analysis in forensic exhibits more difficult. GHB free acid is typically encountered in aqueous solution and in the presence of the lactone, gamma-butyrolactone (GBL), presenting difficulty in Fourier transform infrared (FT-IR) analysis. The strong infrared (IR) absorptivity of the GBL carbonyl band, the shifting of the GBL carbonyl band in aqueous solutions, and the position of the O-H bend for water can mask the main carbonyl band for GHB free acid. Model solutions of beta-hydroxybutyric acid (BHB) and GBL were studied in order to further understand the masking of the GHB free acid carbonyl band in FT-IR analysis. The use of second derivative FT-IR spectroscopy was shown to provide resolution of the free acid carbonyl band, and a presumptive test for GHB free acid was developed and applied. An extension of this work included preparing, for use as a standard reference material, small amounts (< or = 10 mg) of GHB free acid. Preparation was based on the instantaneous reaction of GHB's sodium salt with a stoichiometric amount of hydrochloric acid in aqueous solution, and subsequent isolation of the free acid in neat liquid form. Both FT-IR and proton nuclear magnetic resonance spectra of the neat reference material were obtained and used to verify its identity. The isolation of GHB free acid from actual forensic exhibits is also presented, with identity confirmation using FT-IR. 相似文献
232.
Gilbert MT Menez L Janaway RC Tobin DJ Cooper A Wilson AS 《Forensic science international》2006,156(2-3):208-212
We have investigated the susceptibility of degraded human hair shaft samples to contamination by exogenous sources of DNA, including blood, saliva, skin cells, and purified DNA. The results indicate that on the whole hair shafts are either largely resistant to penetration by contaminant DNA, or extremely easy to successfully decontaminate. This pertains to samples that are both morphologically and biochemically degraded. We suggest that this resistance to the incorporation of contaminant DNA relates to the hydrophobic and impermeable nature of the keratin structures forming the hair shaft. Therefore, hair samples represent an important and underestimated source of DNA in both forensic and ancient DNA studies. 相似文献
233.
Lovett L 《Journal of health politics, policy and law》2005,30(5):803-838
The cartoon character Popeye the Sailor was capable of superhuman feats of strength after eating a can of spinach. Popeye ate spinach because the association of spinach with strength was a product of the first national nutrition crisis in the United States: the 1920s fight against child malnutrition. Spanning the first three decades of the twentieth century, the malnutrition crisis arose from the confluence of many different events including the invention of nutrition science and new standards for height and weight; international food crises created by world war; the rise of consumerism, advertising, and new forms of mass media; and Progressive reformers' conviction that education was a key component of any solution. The history of the malnutrition crisis presented in this essay synthesizes disparate histories concerning advertising, public health, education, consumerism, philanthropy, and Progressive Era reform with original analysis of a major nutrition education program sponsored by the Commonwealth Fund in the 1920s. Because the character of Popeye came to embody one of the nutritional norms advocated in the 1920s, I refer to the influence of culturally constructed social norms on children's beliefs about health and nutrition as the Popeye Principle. The history of the malnutrition crisis demonstrates the importance of understanding the cultural and economic conditions surrounding childhood nutrition, the use and influence of numerical norms, and the mutually reinforcing influences on children's nutritional norms from their parents, peers, teachers, and culture. 相似文献
234.
Christy?A.?VisherEmail author Laura?Winterfield Mark?B.?Coggeshall 《Journal of Experimental Criminology》2005,1(3):295-316
One consequence of the tremendous growth in the number of persons under supervision of the criminal justice system, whether incarcerated, on parole, or on probation, is the effect of this criminal history on finding and keeping a job. Ex-offenders, especially those recently released from prison, face substantial barriers to many types of legal employment; nonetheless, stable employment is one of the best predictors of post-release success. Thus, policy-makers concerned about high recidivism rates face an obvious need to improve the employment prospects of ex-offenders. Over the last 25 years, many programs that were designed to increase employment (and, by so doing, reduce recidivism) among ex-offenders have been implemented and evaluated. [Wilson, D. B., Gallagher, C. A., Coggeshall, M. B. & MacKenzie, D. L. (1999). Corrections Management Quarterly 3(4), 8–18; Wilson, D. B., Gallagher, C. A. & MacKenzie, D. L. (2000). Journal of Research in Crime and Delinquency 37(4), 347–368] conducted a quantitative synthesis and meta-analysis of 33 evaluations of educational, vocational, and work programs for persons in correctional facilities. To date, however, the evaluation literature on employment programs for those with a criminal record who are not in custody has not been systematically reviewed. This paper presents the results of a quantitative meta-analysis of eight random assignment studies of such programs, using the Campbell Collaboration methodology. The results indicate that this group of community employment programs for ex-offenders did not reduce recidivism; however, the experimental design research on this question is small and does not include some of the promising community employment programs that have emerged in the last decade. 相似文献
235.
236.
One of the most frequent causes of death in developed countries is sudden natural death (SND), which is the most common indication for medico-legal autopsies. Cardiac diseases are frequently detected among SND. Mitochondrial DNA (mtDNA) is easily damaged by reactive oxygen species, and it may cause dysfunction in tissues, leading to early events in cardiovascular disease. A specific mtDNA deletion of 4977 bp is associated to aging, myocardial dysfunction, and bioenergetic deficit. The potential link between mtDNA damage and SND has not been investigated before. Our aim was to evaluate the accumulation of the common mtDNA4977-deletion in cardiac muscle samples from autopsies of SND in adults (n = 14) in comparison to control samples from unnatural deaths (n = 12). Serial dilution-polymerase chain reaction method was performed to estimate the proportion of the total mtDNA harboring the mtDNA4977-deletion. Coefficient variation intra-assay was 8%, and inter-assay was 12%. MtDNA4977-deletion percentage was higher in samples obtained from victims of SND than in those from subjects who died of unnatural causes (p < 0.05). No differences in mtDNA4977-deletion were found between SND victims 39-51 years old, and no correlation was found between these samples and age, r = 0.30, p = 0.29 while it was significant among control samples, r = 0.68, p < 0.05. The association between mtDNA4977 deletion with SND victims might offer a tool to provide additional information to clarify complex SND investigations. 相似文献
237.
Tishler CL Bartholomae S Katz BL Landry-Meyer L 《Journal of interpersonal violence》2004,19(9):1042-1062
Mediation is an essential component of custody evaluation and reconciliation services in domestic courts. Data from 306 couples with and without a reported history of domestic violence (DV) who were ordered to attend an assessment for mediation were analyzed to determine differences in the mediation process. More than one third reported a history of DV. Chi-square analysis showed that differences in the mediation process exist between couples reporting DV and couples reporting no DV. A greater proportion of couples with reported DV (a) actually attended the court-mandated assessment session, (b) were deemed unsuitable to participate in the mediation process, (c) were in default of child-support payments, and (d) reported drug and alcohol abuse. No significant differences were found between the two groups in the measured mediation outcomes. Implications for the use of mediation with couples who reported DV and recommendations for future research are discussed. 相似文献
238.
Bedard LE Pate KN Roe-Sepowitz DE 《International journal of offender therapy and comparative criminology》2003,47(5):597-607
This investigation is an empirical evaluation of Esuba, an abuse awareness program implemented in the Florida correctional system. Research has indicated a link between violent and abusive behavior and criminal activity. This study specifically addressed whether the Esuba program had an impact on offenders' self-esteem, stability of self, faith in people, and sensitivity to criticism as measured by the Rosenberg Self-Esteem Scale. The results from the application of the Esuba program to an incarcerated offender population are encouraging. The results suggest that the Esuba program does appear to significantly increase offenders' emotional self-preservation. 相似文献
239.
240.
Laura Cram 《管理》2002,15(3):309-324
The question of the "institutional balance" strikes at the very core of what the European Union is and where it is headed. In Declaration 23 of the Treaty of Nice, member states committed themselves to launching "a deeper and wider debate about the future of the Union" (point 3). As the articles in this volume indicate, in addressing the future of the Union, it is crucial that member states and the institutions dispel the myths upon which some of the need for reform has been conceived. In any institutional reform process, it is vital that the architects of reform avoid what Demsetz has referred to as the "Nirvana fallacy." In examining the institutional balance(s) in the EU and addressing the future of the Union, it is important that the realities of contemporary praxis are fully understood and that unrealistic goals are avoided. The EU can no more be expected to conform to some mythical ideal of "good governance" than can the member states of which it is constituted. 相似文献