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211.
《Justice Quarterly》2012,29(1):157-182
This paper tests a variety of explanations for variation in distrust of local police in the US. As with other attitudes toward the police, there is a substantial race gap in distrust of the police. Our analysis is based upon citizen survey data from 33 cities and data on policing characteristics and the city context for those same cities. It reveals that individual‐level factors representative of a psychological model are of substantial importance in accounting for variation in distrust of the police. City‐level attributes tapping differences in police performance are also important predictors of citizen distrust of the police, even once individual‐level attributes are controlled; and there are important racial differences in the impact of these police performance variables as well, resulting in a largely full accounting of the initial race gap.  相似文献   
212.
How do Belgian citizens see the future of federalism? In the typical consociational Belgium citizens have not had much to say about the federalization process, which has been largely elite-driven. And actually not so much is known about the future of Belgian federalism through the eyes of the citizens. Survey research shows some differences in identity and in institutional preferences between the two language groups, but also a low salience of the issue when they cast a vote. This article, therefore, looks at alternative methods to capture the perceptions of the citizens: focus groups, deliberative experiments and mental maps.  相似文献   
213.
The reduction of modern commercially cremated remains into a fine powder negates the use of traditional methods of skeletal analysis. The literature on the use of cremains weight for estimating aspects of the biologic profile is limited, often with conflicting results. This study re-evaluates the value of weight in the assessment of biologic parameters from modern cremated remains. A sample of adults was collected in northern California (n = 756), with a cremains weight averaging 2737.1 g. Males were significantly heavier than females (mean = 3233.2 g versus mean = 2238.3 g, respectively; p<0.001). Comparison of this sample with other previously reported samples from southern California, Florida, and Tennessee indicates a consistent sex difference, with the most similar mean values to the Tennessee study. Although cremains weight decreases with age as expected, the relationship is weak; thus, cremains weight cannot accurately predict age-at-death. While sex estimation shows considerable accuracy (86.3% for males and 80.9% for females), sectioning points may be population specific.  相似文献   
214.
This study involved the comparative analysis and discrimination of 90 electrical tape adhesives. The objectives included the evaluation of the ability of individual techniques to discriminate samples and the assessment of the ability of the techniques combined to distinguish samples. The techniques utilized were stereomicroscopy, Fourier transform infrared spectroscopy (FTIR), pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), and scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS). Stereomicroscopy, to assess adhesive colors of black, clear/colorless, and clear adhesives with brown tint, resulted in a discrimination of 53%. FTIR analysis yielded eight distinct groups with a discrimination of 67%. Py-GC/MS analysis resulted in 16 groups with a discrimination of 83%. These analyses confirmed and further subdivided the FTIR groups. SEM/EDS resulted in five separate groups at 17% discrimination, increasing the overall discrimination to above 85%.  相似文献   
215.
为了解广西地区猪繁殖与呼吸综合征病毒(PRRSV)流行毒株的分子遗传进化情况,对2004-2010年间广西的PRRSV阳性病料进行了ORF5、ORF7基因扩增和序列分析。结果显示,所获得的毒株均属于美洲型毒株,其ORF5基因间的氨基酸序列同源性为89.6%~99.5%,与VR-2332、Ch-1a、JXA1株的氨基酸序列同源性分别为84.6%~91%、89.6%~95.5%和93%~99%,而与LV的同源性为54.7%~56.7%;ORF7基因间的氨基酸序列同源性为87.1%~99.2%,与VR-2332、Ch-1a、JXA1株的氨基酸序列同源性分别为91.1%~96%、91.9%~96%和89.5%~99.2%,而与LV的同源性为55.6%~58.1%。基于ORF5和ORF7基因核苷酸序列绘制的遗传进化树,可将所有PRRSV分离株分为4个亚群,广西地区的毒株分布在以CH-1a为代表的Ⅱ亚群、以HB-1为代表的Ⅲ亚群和以JXA1为代表的Ⅳ亚群,以Ⅳ亚群为主。表明当前广西PRRSV流行毒株以美洲型Ⅳ亚群为优势基因亚群,并且各毒株间的ORF5和ORF7基因序列存在一定差异,但没有明显的地域特征。  相似文献   
216.
This review brings together a complex and extensive literature to address the question of whether it is possible to distinguish human from nonhuman bone using the histological appearance of cortical bone. The mammalian species included are rat, hare, badger, racoon dog, cat, dog, pig, cow, goat, sheep, deer, horse, water buffalo, bear, nonhuman primates, and human and are therefore not exhaustive, but cover those mammals that may contribute to a North American or Eurasian forensic assemblage. The review has demonstrated that differentiation of human from certain nonhuman species is possible, including small mammals exhibiting Haversian bone tissue and large mammals exhibiting plexiform bone tissue. Pig, cow, goat, sheep, horse, and water buffalo exhibit both plexiform and Haversian bone tissue and where only Haversian bone tissue exists in bone fragments, differentiation of these species from humans is not possible. Other primate Haversian bone tissue is also not distinguishable from humans. Where differentiation using Haversian bone tissue is undertaken, both the general microstructural appearance and measurements of histological structures should be applied. Haversian system diameter and Haversian canal diameter are the most optimal and diagnostic measurements to use. Haversian system density may be usefully applied to provide an upper and lower limit for humans.  相似文献   
217.
218.
This paper reports the results of a series of experiments carried out to determine the precision of soil trace comparisons based on elemental peak height ratios determined by energy-dispersive X-ray analysis (EDXRA) in a variable pressure scanning electron microscope (VP-SEM). Experiments were conducted on 'bulk' soil aggregates, ground powders prepared from the <150 microm soil fractions and on smears of both the bulk soil and <150 microm material placed on cotton cloth. X-ray count data were obtained using area scans and spot analyses at different magnifications. The effects on elemental peak height ratios of varying the SEM chamber pressure, beam spot size, emission current and accelerating voltage were also examined. The peak height ratios for oxygen, silicon, aluminium, potassium, calcium and iron were found to show little variation as a function of chamber pressure, spot size and emission current over the ranges examined, but a strong dependency on accelerating voltage was observed. Within-sample variation in results, expressed by the percentage coefficient of variation, was found to be lowest for area scan analyses of the ground <150 microm fractions and greatest for the spot analyses of the bulk soil aggregates and the <150 microm fractions. We conclude that comparison of elemental peak height ratios determined by EDXRA can be a useful tool for rapid screening of soil samples, especially when combined with investigation of other attributes of the soil traces such as colour, fabric and the composition, shapes and surface textures of individual particles or aggregates within the soil traces. If sufficient material is available and can be readily separated without contamination or loss, higher resolution and more precise elemental data should be obtained by methods such as inductively coupled plasma atomic-emission spectrometry (ICP-AES) or mass-spectrometry (ICP-MS).  相似文献   
219.
The extent and ways in which popular preferences influence government policy are absolutely central to our understanding of modern democracy. Paul Warwick's discussion of these in the European Journal of Political Research in 2010 puts itself at the heart of the debate with its critique of the median mandate theory of McDonald and Budge, proposing an alternative ‘bilateralist’ concept of representation. This article questions whether this concept has much to add to our theoretical understanding of representational processes. However, Warwick's further conceptual points deserve serious consideration. These concern the time horizons within which representative processes work, and the status of the median position given multi‐motivated voting. At the evidential level, Warwick argues that survey‐based measures of voter and party left–right positions fail to produce the correspondence between median and government policy positions that median mandate theory would have us expect. However, survey‐based measures of median voter and party placements obscure important cross‐national variation. Using the Comparative Study of Electoral Systems ( CSES 2007 ), as Warwick does, this article shows that survey respondents norm their own and their country's party positions to their national context. The consequence is to make the political centre in all nations appear similar. Allowing for the relevant cross‐national differences brings the relationship between the median voter and government position back in line with expectations.  相似文献   
220.
This study extends previous work on the sorption of explosives to the hair matrix. Specifically, we have studied the interaction of 2,4,6-trinitrotoluene (TNT) and triacetone triperoxide (TATP) as a function of chemical pretreatment with acetonitrile, neutral and alkaline hydrogen peroxide, methanolic KOH and potassium permanganate, and the morphological changes that accompany these treatments. While differences in vapor pressure can account for quantitative differences between TNT and TATP sorption, both are markedly affected by the chemical rinses. Examination of the hair surface shows different degrees of smoothening following rinsing, suggesting that the attachment to hair is largely a surface phenomenon involving the 18-methyleicosanoic acid lipid layer. Density functional theory calculations were employed to explore possible nucleation sites of TATP microcrystals on the hair. We conclude that some of the sites on melanin granular surfaces may support nucleation of TATP microcrystals. Moreover, the calculations support the experimental finding that dark hair adsorbs explosives better than light hair.  相似文献   
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