首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   7129篇
  免费   476篇
各国政治   338篇
工人农民   226篇
世界政治   466篇
外交国际关系   233篇
法律   5024篇
中国政治   34篇
政治理论   1249篇
综合类   35篇
  2020年   156篇
  2019年   166篇
  2018年   177篇
  2017年   207篇
  2016年   210篇
  2015年   196篇
  2014年   181篇
  2013年   741篇
  2012年   155篇
  2011年   168篇
  2010年   205篇
  2009年   225篇
  2008年   165篇
  2007年   159篇
  2006年   169篇
  2005年   164篇
  2004年   176篇
  2003年   159篇
  2002年   138篇
  2001年   309篇
  2000年   250篇
  1999年   227篇
  1998年   97篇
  1997年   65篇
  1996年   69篇
  1995年   80篇
  1994年   86篇
  1993年   89篇
  1992年   151篇
  1991年   156篇
  1990年   145篇
  1989年   155篇
  1988年   122篇
  1987年   137篇
  1986年   126篇
  1985年   132篇
  1984年   101篇
  1983年   116篇
  1982年   82篇
  1981年   78篇
  1980年   55篇
  1979年   108篇
  1978年   69篇
  1977年   58篇
  1976年   50篇
  1975年   47篇
  1974年   55篇
  1973年   55篇
  1972年   44篇
  1968年   40篇
排序方式: 共有7605条查询结果,搜索用时 15 毫秒
241.
A new political geography has emerged in the Middle East and North Africa (MENA) after the Arab Spring. The transformative impact of the popular upheavals appeared to put an end to long-term authoritarian regimes. Today, the region is far from stable since authoritarian resilience violently pushed back popular demands for good governance and is pushing to restore former state structures. However, the collective consciousness of the popular revolts endures, and a transformative prospect may emerge on the horizon. The chaotic situation is the result of an ongoing struggle between those who seek change and transformation and others in favour of the status quo ante. A critical evaluation of the Arab Spring after five years indicates a continuous process of recalculation and recalibration of policies and strategies. There are alternative routes for an eventual settlement in the MENA region, which are in competition against both regional and transregional quests for a favourable order.  相似文献   
242.
This paper studies Hindu untouchable sweepers of Bangladesh, using a case study of two sweeper communities in Dhaka city. Due to their untouchability, Hindu sweepers in Bangladesh have historically been subjected to discrimination and marginalisation, and are deprived of choices such as free selection of occupation, access to housing, education and other benefits. Contending with the conventional notion that Hinduism maintains social order by caste hierarchies and divisions of labour, this shows how the sweepers of Dhaka city respond to the notion of untouchability and show resistance to caste discrimination. This paper also argues that it is not only a Hindu religious ideology but also historical, colonial, economic, political and social aspects of caste-based discrimination that can explain construction of the notion of Dalit and the marginalisation and resistance of Bangladeshi sweepers.  相似文献   
243.
This study presents a number of pseudo-operational trials on plastic bags investigating the double- and co-fuming process of a one-step fluorescent cyanoacrylate (LumicyanoTM) in comparisons with the two-step process with basic yellow 40 (BY40) staining for the detection of latent fingermarks. The results demonstrate that both Lumicyano solution and dye contribute to the increased detection of latent fingermarks during the double-fuming process (trial 1). Co-fuming the Lumicyano solution and dye separately (at a concentration of 8%) but simultaneously was less effective than 8% Lumicyano (trial 2). Co-fuming Lumicyano 8% and an additional 8% Lumicyano dye by weight was more effective than Lumicyano 8% (trial 3), possibly due to increased fluorescent material deposition during co-fuming allowing for better visualization. The use of BY40 after Lumicyano resulted in a considerable increase in detected fingermarks.  相似文献   
244.
Many studies in the literature have highlighted the utility of virtual 3D databanks as a substitute for real skeletal collections and the important application of radiological records in personal identification. However, none have investigated the accuracy of virtual material compared to skeletal remains in nonmetric variant analysis using 3D models. The present study investigates the accuracy of 20 computed tomography (CT) 3D reconstruction models compared to the real crania, focusing on the quality of the reproduction of the real crania and the possibility to detect 29 dental/cranial morphological variations in 3D images. An interobserver analysis was performed to evaluate trait identification, number, position, and shape. Results demonstrate a false bone loss in 3D models in some cranial regions, specifically the maxillary and occipital bones in 85% and 20% of the samples. Additional analyses revealed several difficulties in the detection of cranial nonmetric traits in 3D models, resulting in incorrect identification in circa 70% of the traits. In particular, pitfalls included the detection of erroneous position, error in presence/absence rates, in number, and in shape. The lowest percentages of correct evaluations were found in traits localized in the lateral side of the cranium and for the infraorbital suture, mastoid foramen, and crenulation. The present study highlights important pitfalls in CT scan when compared with the real crania for nonmetric analysis. This may have crucial consequences in cases where 3D databanks are used as a source of reference population data for nonmetric traits and pathologies and during bone-CT comparisons for identification purposes.  相似文献   
245.
An extensive body of research documents how governing parties generally suffer electoral defeats. Varying explanations have been offered, most of which touch upon the liabilities of policy responsibility. Although media coverage is generally acknowledged as one of these liabilities, few empirical studies have examined how news content affect government support. Based on the fact that voters get their information about politics, policies and societal issues from the media, this article studies how the constant stream of negative news influences incumbent support over a 20-year period in Denmark. Modeling a previously untested argument on the cost of ruling, it shows that the accumulation of bad news throughout tenure exerts a substantial effect on government support.  相似文献   
246.
There is an ongoing debate among practitioners and scholars about the security consequences of transnational migration. Yet, existing work has not, so far, fully taken into account the policy instruments states have at their disposal to mitigate these risks, and reliable evidence is lacking for the effectiveness of such measures. This article addresses both shortcomings as whether and to what extent national migration policies affect the diffusion of terrorism via population movements are analysed. Spatial analyses report robust support for a moderating influence of states’ policies: while terrorism can travel from one country to another via larger migration populations, this only applies to target countries with extremely lax regulations and control mechanisms. This research sheds new light on the security implications of population movements, and it crucially adds to our understanding of governments’ instruments for addressing migration challenges as well as their effectiveness.  相似文献   
247.
Amidst calls for more scrutiny of the failure of infrastructure public–private partnerships (PPPs), uncertainty about how we can measure failure remains, and little systematic evidence illuminates its likelihood. Our mixed‐methods design explores the notion of failure and identifies the conditions under which it happens. The first phase of our research employs documentary analysis and semistructured expert interviews, and identifies project cancellation as capturing the most severe occurrences of failure. A second phase statistically analyzes a unique World Bank data set capturing the provisions of over 4,000 infrastructure PPPs launched between 1990 and 2015 in 89 countries. We find robust evidence supporting the theoretical claim that PPPs are less likely to be canceled in countries with more veto points among their political institutions to restrain politicians from intervening in policy implementation. Cancellation is a rare, but valid indicator of failure, and the importance of veto players clarifies how political risk operates in this context.  相似文献   
248.
Innovating upon previous field experiments and theories of identity‐based discrimination, we test whether public officials are using searches (“identity‐questing”) to profile citizens and acting on latent biases. Pairs of “institutional” and “noninstitutional” requesters send lower and moderate burden freedom of information (FOI) requests—providing no identity cues apart from undistinctive names, e‐mails, and ID numbers—to nearly 700 of Brazil's largest municipalities. Results show institutional requesters receive one‐fifth more responses than noninstitutional comparators. For moderate versus lower burden requests, noninstitutional requesters are 11% less likely to receive a compliant response than their institutional comparators. The only plausible explanation for these results is identity‐questing, a phenomenon that has far‐reaching policy implications. Most of the world's FOI laws, for example, contain vague ID obligations, which translate incoherently from laws to regulation and practice. Results enjoin public service providers to protect the identities of citizens by default or upon request.  相似文献   
249.
Cholesterol and squalene are fatty materials of latent fingermarks that can be utilized for dating methodologies and visualization techniques. Previous studies have suggested these compounds undergo degradation in fingermarks as a function of time (days) and light at ambient temperature. However, studies assessing how their composition changes at low and high temperatures over short periods of time (hours) have not been published previously. Here, we performed quantitative analysis of cholesterol and squalene in natural fingermark residue using PVDF membrane, after exposure to a range of temperatures (−20 to 100°C) for 4 and 8 h. We found that levels of both fatty materials remained constant at −20 to 60°C, but both showed significant reduction at 100°C, over short exposure times. These results indicate that cholesterol and squalene are detectable at −20 to 60°C, whereas at 100°C or higher, both are lost due to rapid thermal degradation.  相似文献   
250.
Microbial communities have potential evidential utility for forensic applications. However, bioinformatic analysis of high-throughput sequencing data varies widely among laboratories. These differences can potentially affect microbial community composition and downstream analyses. To illustrate the importance of standardizing methodology, we compared analyses of postmortem microbiome samples using several bioinformatic pipelines, varying minimum library size or minimum number of sequences per sample, and sample size. Using the same input sequence data, we found that three open-source bioinformatic pipelines, MG-RAST, mothur, and QIIME2, had significant differences in relative abundance, alpha-diversity, and beta-diversity, despite the same input data. Increasing minimum library size and sample size increased the number of low-abundant and infrequent taxa detected. Our results show that bioinformatic pipeline and parameter choice affect results in important ways. Given the growing potential application of forensic microbiology to the criminal justice system, continued research on standardizing computational methodology will be important for downstream applications.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号