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Banknote evidence is often submitted after a suspect has attempted to disguise or remove red dye stain that has been released because of an anti-theft device that activates after banknotes have been unlawfully removed from bank premises. Three chlorinated compounds have been synthesized as forensic chemical standards to indicate bank security dye bleaching as a suspect's intentional method for masking a robbery involving dye pack release on banknotes. A novel, facile synthetic method to provide three chlorinated derivatives of 1-(methylamino)anthraquinone (MAAQ) is presented. The synthetic route involved Ultra Clorox bleach as the chlorine source, iron chloride as the catalyst, and MAAQ as the starting material and resulted in a three-component product mixture. Two mono-chlorinated isomers (2-chloro-1-(methylamino)anthraquinone and 4-chloro-1-(methylamino)anthraquinone) and one di-chlorinated compound (2,4-dichloro-1-(methylamino)anthraquinone) of the MAAQ parent molecule were detected by gas chromatography mass spectrometry (GC-MS), and subsequently isolated by liquid chromatography (LC) with postcolumn fraction collection. Although GC-MS is sensitive enough to detect all of the chlorinated products, it is not definitive enough to identify the structural isomers. Liquid-state nuclear magnetic resonance (NMR) spectroscopy was utilized to elucidate structurally the ortho- and para-mono-chlorinated isomers once enough material was properly isolated. A reaction mechanism involving iron is proposed to explain the presence of chlorinated MAAQ species on stolen banknotes after attempted bleaching.  相似文献   
64.
We have analyzed variation of the mitochondrial DNA (mtDNA) hypervariable segments I and II (HVS-I and HVS-II) in 185 randomly chosen individuals from Korea to provide an expanded and reliable Korean database. Combined sequence comparison of HVS-I and HVS-II led to the identification of 167 different haplotypes characterized by 154 variable sites. One hundred and fifty-one of the haplotypes were individual-specific, 14 were found in two individuals and 2 were found in three individuals. A pairwise comparison of the 185 HVS-I/II sequences found an average of 10.11 +/- 4.63 differences between individuals. The random match probability and gene diversity for the combined hypervariable regions were estimated at 0.66% and 0.9988, respectively. Analyzing the expanded database including three previously reported data sets and the present data using haplogroup-based comparisons and comparison with closely related sequences allowed errors to be detected and eliminated, thus considerably improving data quality. Sample division comparisons based on PhiST genetic distance measures revealed no significant population differentiation in the distribution of mtDNA sequence variations between the present data set and a database in The Scientific Working Group on DNA Analysis Methods (SWGDAM), but did indicate differences from other sets of data. Based on the results of mtDNA profiles, almost all of the mtDNA types studied here could be classified into subsets of haplogroups common in east Asia, and show that the Koreans possess lineages from both the southern and the northern haplogroup complexes of east Asian populations. The new data, combined with other mtDNA sequences, demonstrate how useful comparison with closely related mtDNA sequences can be for improving database quality, as well as providing haplotype information for forensic and population genetic analyses in the Korean population.  相似文献   
65.
A method is suggested that allows the use of loci that have shown allelic dropout in kinship analysis as used for disaster victim identification (DVI) and missing person work (MP). This approach uses an extension of a previously published approach to modelling allelic dropout. This method may salvage some information in cases where allelic dropout is hindering DVI or MP work particularly in reconciliations involving a large number of bodies and pedigrees. It should not replace the pursuit of more complete DNA profiles by the normal rework process for such samples.  相似文献   
66.
The purpose of this study was to determine the performance characteristics of the Cozart Amphetamine Microplate EIA for detecting amphetamine in oral fluid. Oral fluid samples were collected using the Cozart RapiScan Collection System from 135 volunteer donors from drug treatment clinics. A further 35 oral fluid samples were collected from volunteer donors who were not drug users. The samples were analyzed in the laboratory using the Cozart Amphetamine Microplate EIA and confirmed using gas chromatography-mass spectrometry (GC-MS). The samples were stored frozen until analysis by GC-MS. The intra-assay precision for the Cozart Amphetamine Microplate EIA for amphetamine in oral fluid over forty assays was 2.74-7.1% CV (within assay) and 3.4-7.0% CV (within day). A total of 78 samples were positive for various amphetamines and related designer drugs. The Cozart Amphetamine Microplate EIA, using a cutoff of 45 ng/ml amphetamine equivalents in neat oral fluid, had a sensitivity of 91.7+/-3.3% and a specificity of 95.9+/-1.9% versus GC-MS using a cutoff of 30 ng/ml. A series of potential adulterants of oral fluid were evaluated and shown not to alter the outcome of the test result.  相似文献   
67.
Discriminant analysis of both observational and records data from two juvenile court systems is used to assess differences in the type and activities of the people involved in legal processing of status and nonstatus offenders. The analysis indicates that there are differences between the processing of the two categories of offenders; however, contrary to expectations, the most powerful discriminating variables (detention and petitioner) are not those related to the degree in which the justice system has implemented the formalities mandated by the Gault decision. It is concluded that statutory distinctions between legal categories of juveniles have virtually no relevance for the degree of formality with which these cases are processed by the courts.  相似文献   
68.
Developing countries are pressured to adopt administrative solutions that the international community considers best practice. Some claim that these practices do not fit such contexts. How could one assess the fit or relevance of a best practice? This article suggests a basic answer: Look at the degree of difference between the proposed adoption context and the context in which such practice emerged as ‘best’. This answer emerges from a discussion on the basis of the new institutional ideas about change and diffusion. An empirical analysis of public financial management reform in African countries suggests support for this answer: Good practices are most evident in countries least different to the developed nations where practices originated and least evident in countries most different to these developed nations. The article contributes to a literature on best practice and yields fundamental messages for development, including the point that best practices are limited as administrative solutions in many developing countries. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
69.
The U.S. electricity market, like electricity markets in most countries, is heavily dependent on fossil-fuel generation from centralized power applications. This paper reviews the factors that led to the sector??s reliance on fossil fuels and presents a future vision of the U.S. electricity sector based on a varied spectrum of sustainable energy resources ranging in scale from large, centralized facilities to small, localized energy systems. This spectrum includes low-emissions energy and energy efficiency, as well as macro-generation, micro-grids, distributed generation, micro-generation and end-user conservation. We discuss the evidence that each element of this spectrum is a viable and proven technology, the balanced integration of which could shape an electricity sector that adheres to sustainability principles. This paper concludes with a discussion of the institutional barriers that need to be addressed to successfully achieve a transition toward a more future sustainable electricity sector based on the variations in scale.  相似文献   
70.

Purpose

This article provides a critical review of the state of research on the gang membership-violent victimization relationship.

Methods

This study examines a comprehensive list of published quantitative studies that have assessed the relationship between gang membership and violent victimization.

Results

By examining strengths and weaknesses of the design features of various studies, this article identifies theoretical, conceptual, methodological, and statistical issues that should be considered when interpreting the causal effect of gang membership on violent victimization. Some of the methodological and design issues discussed include, but are not limited to, consequences of failing to establish temporal order, failure to conduct sensitivity analyses to determine treatment effects, use of bootstrapping methods with propensity score analysis, measurement of violent victimization, and corrections for dependence in matched samples of gang and non-gang members.

Conclusion

Suggestions for future research are provided that will help advance the empirical study of the gang membership-violent victimization nexus.  相似文献   
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