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941.
David M. Konisky Department of Political Science, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Room E53-386, Cambridge, MA 02139 e-mail: sda{at}mit.edu e-mail: konisky{at}mit.edu (corresponding author) Studies of voter turnout across states find that those withmore facilitative registration laws have higher turnout rates.Eliminating registration barriers altogether is estimated toraise voter participation rates by up to 10%. This article presentspanel estimates of the effects of introducing registration thatexploits changes in registration laws and turnout within states.New York and Ohio imposed registration requirements on all oftheir counties in 1965 and 1977, respectively. We find thatthe introduction of registration to counties that did not previouslyrequire registration decreased participation over the long termby three to five percentage points. Though significant, thisis lower than estimates of the effects of registration fromcross-sectional studies and suggests that expectations aboutthe effects of registration reforms on turnout may be overstated.  相似文献   
942.
  • This paper explores the institutional and political dynamics of the Business Council of Australia (BCA), a unique form of big business association which relies on the active involvement of its one hundred or so CEO members. The paper argues that associations such as the BCA confront a range of serious institutional problems in their attempts to wield political power, or more modestly perhaps, policy influence. First, they confront a disconnect between ‘structural’ and ‘instrumentalist’ articulations of business power. The key source of business power resides in business control over the economy and the investment process, a form of power wielded at the company level not at the level of business associations. When engaged in instrumentalist or overt forms of political activism, the BCA also confronts serious collective action problems. It is also argued that the influence of the BCA seems to have declined over time and that this can partly be traced back to declining CEO commitment rooted in changing institutional and structural dynamics in the corporate world.
Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
943.
In forensic image processing, it is often important to be able to separate a feature from an interfering background or foreground, or to demonstrate colors within an image to be different from each other. In this study, a color deconvolution algorithm that could accomplish this task is described, and it is applied to color separation problems in document and fingerprint examination. Subtle color differences (sometimes invisible to the naked eye) are found to be sufficient, which is demonstrated successfully for several cases where color differences were shown to exist, or where colors were removed from the foreground or background. The software is available for free in the form of an Adobe Photoshop-compatible plug-in.  相似文献   
944.
Age-related changes of arachnoid foveae have been described, but objective, quantitative analyses are lacking. A new quantitative method is presented for estimation of change in total volume of arachnoid foveae with age. The pilot sample consisted of nine skulls from the Palmer Anatomy Laboratory. Arachnoid foveae were filled with sand, which was extracted using a vacuum pump. Mass was determined with an analytical balance and converted to volume. A reliability analysis was performed using intraclass correlation coefficients. The method was found to be highly reliable (intraobserver ICC = 0.9935, interobserver ICC = 0.9878). The relationship between total volume and age was then examined in a sample of 63 males of accurately known age from the Hamann-Todd collection. Linear regression analysis revealed no statistically significant relationship between total volume and age, or foveae frequency and age (alpha = 0.05). Development of arachnoid foveae may be influenced by health factors, which could limit its usefulness in aging.  相似文献   
945.
Prostitute women have the highest homicide victimization rate of any set of women ever studied. We analyzed nine diverse homicide data sets to examine the extent, trends, and perpetrators of prostitution-related homicide in the United States. Most data sources substantially under-ascertained prostitute homicides. As estimated from a conservative capture-recapture analysis, 2.7% of female homicide victims in the United States between 1982 and 2000 were prostitutes. Frequencies of recorded prostitute and client homicides increased substantially in the late 1980s and early 1990s; nearly all of the few observed pimp homicides occurred before the late 1980s. These trends may be linked to the rise of crack cocaine use. Prostitutes were killed primarily by clients, clients were killed mainly by prostitutes, and pimps were killed predominantly by pimps. Another conservative estimate suggests that serial killers accounted for 35% of prostitute homicides. Proactive surveillance of, and evidence collection from, clients and prostitutes might enhance the investigation of prostitution-related homicide.  相似文献   
946.
Reported herein is the suicidal asphyxiation of a young man due to exhaustion of oxygen in the interior of a sealed automobile into which the exhaust emissions were diverted. His blood carboxyhemaglobin concentration was less than 5% saturation. The car was equipped with a catalytic converter and when tested, the exhaust carbon monoxide concentration was 0.01%.  相似文献   
947.
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   
948.
The combination of soil's ubiquity and its intrinsic abiotic and biotic information can contribute greatly to the forensic field. Although there are physical and chemical characterization methods of soil comparison for forensic purposes, these require a level of expertise not always encountered in crime laboratories. We hypothesized that soil microbial community profiling could be used to discriminate between soil types by providing biological fingerprints that confer uniqueness. Three of the six Miami-Dade soil types were randomly selected and sampled. We compared the microbial metagenome profiles generated using amplicon length heterogeneity-polymerase chain reaction analysis of the 16S rRNA genes with inductively coupled plasma optical emission spectroscopy analysis of 13 elements (Al, B, Ca, Cu, Fe, K, Mg, Mn, Na, P, S, Si, and Zn) that are commonly encountered in soils. Bray-Curtis similarity index and analysis of similarity were performed on all data to establish differences within sites, among sites, and across two seasons. These data matrices were used to group samples that shared similar community patterns using nonmetric multidimensional scaling analysis. We concluded that while chemical characterization could provide some differentiation between soils, microbial metagenome profiling was better able to discriminate between the soil types and had a high degree of reproducibility, therefore proving to be a potential tool for forensic soil comparisons.  相似文献   
949.
Violent Sex Offenses: How are They Best Measured from Official Records?   总被引:1,自引:1,他引:0  
In the United States, sexually violent predator (SVP) commitment statutes generally require assessment of an offender's risk of subsequent sexual violence. Current actuarial methods for predicting sexual reoffending were actually designed to predict something else—charges or convictions for offenses deemed sexual based on information obtained from police “rapsheets” alone. This study examined the referral and past offenses of 177 sex offenders. Results showed that police rapsheets (and data based on them) underestimated the number and severity of sexually motivated violent offenses for which sex offenders were actually apprehended. Rapsheet violent offenses seemed a more accurate index of the conduct addressed by SVP legislation than were rapsheet sex offenses. We suggest that, when evaluating sex offenders for SVP status, actuarial instruments designed to predict violent recidivism (as measured by rapsheet violent reoffenses) might be preferable to those designed to predict sexual recidivism (as measured by rapsheet sexual reoffenses).
Marnie E. RiceEmail:
  相似文献   
950.
Drug screening through urinalysis is a widely accepted tool for rapid detection of potential drug use at a relatively low cost. It is, therefore, a potentially useful method for detecting and monitoring drug use in a variety of contexts such as the criminal justice system, pre-employment screening and a variety of treatment centers. This article explores the efficacy of two commercially available drug-screening assays: Online KIMS assay (Roche) and EMIT II assays. First, we evaluate the sensitivity and specificity of two immunoassays. A total of 738 urine samples were collected among adult arrestee populations from Chicago, New Orleans and Seattle through the Arrestee Drug Abuse Monitoring (ADAM) program. Partial samples were split within one laboratory and analyzed by both enzymes multiplied immunoassay technique (EMIT) II and kinetic interaction of microparticle in solution (KIMS) assays for a 10-drug panel (amphetamine, barbiturates, benzodiazepines, marijuana, cocaine, methadone, methaqualone, opiate, phencyclidine and propoxyphene). Gas chromatography-mass spectrometry (GC-MS) was used as a confirmation method for all positives from either EMIT II or KIMS for all experiments. Second, the paper examines whether using different testing laboratories plays a role in the final results. The same experiments were repeated at two different testing locations: one in California and one in London and England. Third, the paper studies whether drug testing results vary between two laboratories when each of them had used their own routine screening method: the Forensic Science Service (FSS) at Birmingham, United Kingdom with KIMS assay and Medscreen Limited at London, United Kingdom with EMIT II. In summary, both EMIT II and KIMS assays generate fairly consistent results. The concordance rate against each of the 10 drugs tested is relatively high (97.4-100%). The discrepancies, in most cases, occurred at drug concentrations near the cut-off levels. There were more discrepant results between two laboratories compared to when specimens were analyzed at the same laboratory using two different assays.  相似文献   
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