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   311篇
  免费   25篇
各国政治   46篇
工人农民   13篇
世界政治   38篇
外交国际关系   27篇
法律   157篇
政治理论   52篇
综合类   3篇
  2023年   7篇
  2022年   5篇
  2021年   7篇
  2020年   8篇
  2019年   15篇
  2018年   22篇
  2017年   26篇
  2016年   22篇
  2015年   14篇
  2014年   21篇
  2013年   62篇
  2012年   9篇
  2011年   12篇
  2010年   14篇
  2009年   5篇
  2008年   8篇
  2007年   10篇
  2006年   4篇
  2005年   9篇
  2004年   11篇
  2003年   7篇
  2002年   11篇
  2001年   5篇
  1998年   1篇
  1997年   4篇
  1996年   1篇
  1993年   2篇
  1992年   1篇
  1991年   1篇
  1990年   2篇
  1989年   1篇
  1988年   1篇
  1986年   2篇
  1985年   1篇
  1984年   1篇
  1979年   2篇
  1975年   1篇
  1966年   1篇
排序方式: 共有336条查询结果,搜索用时 46 毫秒
311.
312.
The present article tests predictions of rational political business cycle models using a large and previously unexplored data set of Portuguese municipalities. This data allows for a clean test of these predictions due to the high level of detail on expenditure items, an exogenous fixed election schedule, and homogeneity of Portuguese local governments with respect to policy instruments and institutions. Estimation results clearly reveal the opportunistic behaviour of local governments. In pre-electoral periods, they increase total expenditures and change their composition favouring items that are highly visible to the electorate. This behaviour is consistent with an effort to signal competence and increase chances of re-election.  相似文献   
313.
Allele and haplotype frequencies of 15 chromosome STR loci included in the kit PowerPlex16 System from Promega, were determined in a sample of unrelated males from Guiné-Bissau, a country from the west African coast. All individuals were subjected to an interview in order to make sure that their ancestors belonged to the same ethnic group. This way we intended to look for possible inter-ethnic differences. PowerPlex 16 includes STRs not studied before in any multi-ethnic population. The kit includes two new allele markers (Penta D and Penta E), which are very useful either in forensics or population genetic studies. The Guinean population presents significant differences when compared with other African populations.  相似文献   
314.
Nitrites are commonly used in the chemical, pharmaceutical, and food industries. Recently, they have been identified in cases of voluntary intoxication. We report the case of a 13-year-old girl who was found lifeless on her bed next to a glass containing a white powder and a bottle containing a white powder with a moistened appearance. External examination and autopsy revealed a nonspecific asphyxia syndrome, which was confirmed by the pathological analysis. Analysis of the samples revealed metoclopramide in the peripheral blood at a concentration of 0.402 mg/L (LC–HRMS). An analysis of the gastric contents was carried out after sodium nitrite was detected in the powders found near the body (Raman spectrometry). Nitrites were found in the gastric fluid at a concentration of 30.9 mg/L. Death occurred secondary to anoxia, following ingestion of nitrites; suicide kits are available on the web and nitrites are relatively easy to source and inexpensive. Nitrites are delivered in powder form to be dissolved in liquid, which may then be consumed with metoclopramide (or an alternative anti-emetic drug) to maximize absorption and reduce emesis. The toxic effect of nitrites lies in their oxidizing power, causing the transformation of hemoglobin into methemoglobin, which, when it accumulates, induces tissue anoxia resulting in death. There has been an alarming increase in the number of cases linked to suicide using nitrites or a nitrite suicide kit. The fact that nitrites are readily available online underscores the importance of establishing effective preventive measures such as limiting the access and use of this chemical.  相似文献   
315.
Currently, SEM-EDS is used to detect gunshot residue (GSR) from the presence of Ba, Pb, and Sb in the sample. However, the development of new nontoxic ammunition (NTA) has prevented conventional metals from being found. In this work, we aim to determine the presence of an inorganic luminescent chemical marker based on rare earth in gunshot residues using the technique of squarewave voltammetry (SWV). After firing, the luminescent complex [(Eu2Zr)(btc)3(Hbtc)0.5.6H2O], which is used as a chemical marker, can be detected under a UV lamp. An aqueous solution with 0.1 mol L−1 KCl as supporting electrolyte can be easily collected on carbon paste electrode surfaces for SWV analysis A = 100 mV, f = 10 Hz, and step potential of 5 mV are required. The luminescent marker incorporated into the carbon paste electrode showed two anodic peak currents in the region of 0.4 V (vs Ag/AgCl) and at 0.75 V (vs Ag/AgCl) and also a cathodic one in 0.4 V (vs Ag/AgCl). SEM-EDS was able to analyze the same voltammetric results for conventional and nontoxic ammunition containing the luminescent marker. Therefore, voltammetry and SEM-EDS are valid for detecting the new residue marker in GSR. Despite this, the electrochemical method is still more advantageous because of its low cost and lack of expensive equipment and supplies in forensic laboratories.  相似文献   
316.
Human remains detection dogs (HRDD) are commonly used by law enforcement agencies to search for cadavers. Biological material is typically used as a training stimulus, also called aids, to train dogs to recognize the smell of cadavers. While HRDD training approaches have received extensive attention, information remains limited on the olfactory cues used to train them. Here, we aimed to decipher the chemical basis of detection dog olfaction. Five specific objectives were explored to precise whether the composition or the concentration of the training aids drives the HRDDs responses. We recorded the behavioral responses of four HRDDs exposed to different cadaveric-like smells. We found that HRDDs recognized a simplified synthetic aid composed of cadaveric compounds. The lowest concentration at which HRDDs continued to perceive the cadaveric smell was determined. HRDDs were not impacted by slight modifications to the chemical composition of a blend of odors that they have been trained with. HRDDs associated sulfur and nitrogen compounds as human cadaver. Our findings highlight a lack of specificity of HRDDs to cadaveric compounds, which could lead to error of detection. Moreover, all dogs did not positively respond to the same blends, despite being trained with the same aids and procedure. However, we confirmed that dogs could be trained with a simplified blend of molecules. The chemical composition of a training aid has, therefore, high consequences on the performance of the trained animal, and this conclusion opens additional questions regarding olfaction-based detection animals.  相似文献   
317.
This study explores how local governments and their development partners—that is, donors, non‐governmental organisations and private companies—structure their partnerships as they work together to provide services to communities. Cases of collaboration between four organisations working in the rural water supply sector and six local governments in Malawi are studied. Using a cross‐case qualitative methodology, we illustrate how power and control translate into practices, leading to different levels of local government involvement in service delivery. This study contributes to the literature on cross‐sector partnerships in particular by developing empirically‐based propositions that help explain the dynamic trajectories that partnerships between local governments and their development partners can take. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
318.
Globalization is generating new forms of citizenship that often go beyond the institutional perception of social identity. These new forms of citizenship are developed in a scalable way to a greater extent than rights and obligations, and are entirely managed by the citizens themselves. To demonstrate empirical support for this issue, the case of minority communities in Turkey constitutes one of the most relevant examples, since citizenship in this country has long been associated with an idea of political loyalty and total allegiance to the nation-state. The main purpose of this article is to show how urban space and urban protest allow minorities to find alternative forms of expression for their collective identity, and to create a new understanding of citizenship beyond the classical definition, being based instead on institutional representation. The aim of this research is to examine the process of urban transformation in Istanbul, how this phenomenon shapes the structure of cities and how it gives rise to social resistance and protest, especially in neighborhoods housing minority communities. In this context, the article focuses on planning movements in Turkey through a comparative study of two urban planning projects and the citizens' protests against them.  相似文献   
319.
Much of the existing literature suggests that ethnic diversity undermines economic development. However, there are also ways in which local ethnic diversity might be beneficial, and we show that in the case of Ethiopian child health, the benefits of diversity can outweigh the costs. We find that children in relatively diverse communities are better nourished and more likely to receive a full set of vaccinations. There is some evidence that one explanation for this effect is that women in relatively diverse communities are better informed about health issues and more empowered in making healthcare decisions.  相似文献   
320.
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