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The otherwise extensive historiography of slavery in colonial America has rather neglected the overseer and his family, as indeed the wider historiography of colonial society has often neglected the white poor. By considering, specifically, the role of overseers' wives, this article seeks to recover the history of poor white women who, although often vilified by their employers for their allegedly wayward behaviour, made a significant contribution, economically and socially, to the plantation community. By so doing, it casts fresh light upon white women who lived on the margins of wider colonial society and the shadowy ‘edges’ of slavery itself.  相似文献   
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Spatially offset Raman spectroscopy (SORS) is a powerful new technique for the non-invasive detection and identification of concealed substances and drugs. Here, we demonstrate the SORS technique in several scenarios that are relevant to customs screening, postal screening, drug detection and forensics applications. The examples include analysis of a multi-layered postal package to identify a concealed substance; identification of an antibiotic capsule inside its plastic blister pack; analysis of an envelope containing a powder; and identification of a drug dissolved in a clear solvent, contained in a non-transparent plastic bottle. As well as providing practical examples of SORS, the results highlight several considerations regarding the use of SORS in the field, including the advantages of different analysis geometries and the ability to tailor instrument parameters and optics to suit different types of packages and samples. We also discuss the features and benefits of SORS in relation to existing Raman techniques, including confocal microscopy, wide area illumination and the conventional backscattered Raman spectroscopy. The results will contribute to the recognition of SORS as a promising method for the rapid, chemically specific analysis and detection of drugs and pharmaceuticals.  相似文献   
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This research examined the “mental health literacy” of adolescents concerning eating-disordered behavior. A vignette describing a fictional 16-year old female meeting diagnostic criteria for bulimia nervosa was presented to 522 female high school students, followed by a series of questions concerning treatment of and treatment-seeking for the problem described. Results indicated that primary care practitioners, mothers and close female friends were most highly regarded as potential sources of help. Self-help interventions, including the use of vitamins and minerals, were also highly regarded, whereas participants were less positive about the benefits of mental health specialists and ambivalent about the use of anti-depressant medication. Most participants believed that the problem described would be difficult to treat, and that relapse was likely even given appropriate treatment. An additional finding of note was that among participants with a high level of eating disorder symptoms (n=36, 6.9%), recognition of an eating problem was poor. We conclude that beliefs likely to be conducive to low and/or inappropriate treatment-seeking for eating problems may be common among adolescent girls. In addition, the findings suggest that prevention programs for the eating disorders need to target not only at-risk individuals, but also individuals in their immediate social environment.  相似文献   
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Using panel data that track individual students from year to year, we examine the effects of charter schools in North Carolina on racial segregation and black‐white test score gaps. We find that North Carolina's system of charter schools has increased the racial isolation of both black and white students, and has widened the achievement gap. Moreover, the relatively large negative effects of charter schools on the achievement of black students is driven by students who transfer into charter schools that are more racially isolated than the schools they have left. Our analysis of charter school choices suggests that asymmetric preferences of black and white charter school students (and their families) for schools of different racial compositions help to explain why there are so few racially balanced charter schools. © 2006 by the Association for Public Policy Analysis and Management.  相似文献   
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It is clear that urban economic development practices in Ontario tend to cluster in certain classifications. The most widely and consistently used practices are in the area of marketing. On average, nine out of eleven techniques are practised by the cities surveyed. Governance tools and infrastructure investments are also fairly widely employed, with an average of six out of ten uniformly used. Governmental regulations, land and property management activities, and financial tools are less widely employed, with averages of five of thirteen, four of eleven, and two of twelve techniques practised by all cities respectively. In total, cities in Ontario employ an average of twenty-five out of fifty-seven economic development techniques listed. The ten most widely practised techniques across all categories are identified in Table 6. Again, marketing activities figure predominantly. However, landbased incentives and initiatives such as land acquisition, industrial zoning and industrial parks, and infrastructure improvements also are important. Based on these findings, it appears that cities in Ontario offer a range of economic development incentives which conforms closely to those widely practised by other cities. Marketing, site acquisition, and infrastructure improvement are among the most commonly used techniques according to literature. Indeed, because much of the literature focuses on cities in the United States, this research also suggests that similar economic development incentives are offered by cities in Canada and the United States. However, financial incentives such as tax abatements, loans, and loan guarantees are notable by their absence in Ontario cities. Does the limitation on bonuses affect economic development practices in the other categories? In other words, what appears to be the result of provincial restrictions on bonuses? Based on survey results and personal interviews with a small sample of economic development officials in Ontario, it does seem that restrictions have had some impact. While common techniques do centre in the marketing and land based areas, it appears that Ontario cities are also more likely to use more innovative means of attracting economic development. For example, business incubators and training programs are utilized by over 25 per cent of the cities. Thus these techniques, often promoted in the literature as more advantageous to cities, seem to be used more widely in Ontario than in many other cities. Regulations to limit or control certain facets of development also seem more prevalent than easing governmental regulations to promote development. Finally, some innovative techniques such as awards for research and development are also evident. While many economic development officials acknowledge that provincial restrictions limit their ability to compete with other cities, particularly those in the United States (52 per cent agree), they are split over whether such restrictions are too extreme (40 per cent feel they are too restricted, 43 per cent feel that they are not). In interviews it was often suggested that such limitations do reduce the inter-city competition for development which often drives economic development policies in cities that are allowed to offer tax abatements and other incentives. Further research is warranted to explore more fully the effect of restrictions on economic development bonuses. If such limitations regularly result in practices that are judged to be effective in promoting economic development, then such policies as those contained in the Municipal Act appear promising.  相似文献   
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