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   188篇
  免费   12篇
各国政治   14篇
工人农民   12篇
世界政治   18篇
外交国际关系   7篇
法律   125篇
中国政治   1篇
政治理论   22篇
综合类   1篇
  2023年   4篇
  2022年   2篇
  2021年   3篇
  2020年   12篇
  2019年   10篇
  2018年   9篇
  2017年   9篇
  2016年   12篇
  2015年   7篇
  2014年   7篇
  2013年   27篇
  2012年   6篇
  2011年   4篇
  2010年   2篇
  2009年   7篇
  2008年   5篇
  2007年   10篇
  2006年   7篇
  2005年   12篇
  2004年   15篇
  2003年   10篇
  2002年   5篇
  2001年   6篇
  2000年   2篇
  1999年   3篇
  1998年   1篇
  1996年   2篇
  1991年   1篇
排序方式: 共有200条查询结果,搜索用时 15 毫秒
151.
Seven Y-specific STR loci (DYS19, DYS389I, DY5389II, DYS390, DYS391, DYS392 and DYS393) were studied in five populations from the Iberian Peninsula: Andalusia, Valencia, Basque Country, Galicia and Northern Portugal. Haplotype and allele frequencies of these seven Y-chromosome STRs were estimated. Observed haplotype diversities are in a range between 0.96 (Basque Country) and 0.99 (Valencia and Andalusia). Significant population differentiation was registered between Basques and all the other Iberian populations and also between Valencia and Northern Portugal.  相似文献   
152.
This research has been designed with the purpose of analysing the influence of both the composition of academic spin-offs’ management teams and the potential conflict emerged within such teams on the degree of entrepreneurial orientation exhibited by academic spin-offs. To this end, we have used the upper echelon theory as theoretical background and have analysed the impact of the proportion of non-academic managers within management teams, the heterogeneity of such teams with respect to the age and main educational area of their managers, as well as the potential mediating role of the conflict emerged. Drawing on a database of 167 Spanish academic spin-offs, results show, on the one hand, that the presence of non-academic managers within management teams is a key factor in the academic spin-offs' exhibitions of higher levels of entrepreneurial orientation and, on the other hand, that conflict fully mediates the relationship between management teams' age heterogeneity and entrepreneurial orientation.  相似文献   
153.
154.
155.
Ecstasy is the name given to a large group of substances known as “club drugs” traded in the form of tablets, powder and liquid that present a varied composition, including mainly 3,4-methylenedioxymethamphetamine (MDMA) and analogous substances, in addition to the growing presence of new psychoactive substances. Based on this, clandestinely produced tablets (“ecstasy tablets”) seized by police in Santa Catarina in the period from 2011 to 2017 were analyzed. During the study period, 3472 seizures occurred, which resulted in total 498,443 tablets seized. Seventy nine substances were identified. In the year 2011, about 90% of the tablets contained MDMA. This number decreased to 66.6% in 2017. On the other hand, there was an increase in the number of tablets that mainly contained synthetic cathinones, as well as tryptamine and piperazine derivatives. Police seizures in the metropolitan region of Florianópolis and on the coast prevailed over the rest of the state.  相似文献   
156.
The concentrations of lead (Pb), barium (Ba), and antimony (Sb), characteristic of GSR, were determined in soil sediments and immature (larvae) of cadaveric flies of the family Calliphoridae, by inductively coupled plasma mass spectrometry (ICP-MS). This research refers to a case study from two real crime scenes in which the corpses were in an advanced state of decomposition. In case 1, the victim had holes similar to gunshot wounds, and in case 2, there was no evidence of perforations in the corpse. Soil sediment collection was performed at three different points of the terrain, at a minimum distance of 10 m from the corpse, for cases 1 and 2. In relation to the collection of immatures, larvae were collected in regions of the mouth, nose, and orifices similar to the entry of firearms projectile into the body, for case 1, and collection of larvae and pupae, located on the body and underneath it, for case 2. It was possible to detect and quantify the three elements of interest (Pb, Ba, and Sb) by ICP-MS in both sediment and cadaveric larvae. Concentrations of 4.44, 8.74, and 0.08 μg/g were obtained for Pb, Ba, and Sb, respectively, in the soil for case 1. For the case 2, the concentrations in Pb, Ba, and Sb were from 16.34 to 26.02 μg/g; from 32.64 to 57.97 μg/g and from 0.042 to 0.30 μg/g, respectively. In the larvae, Pb, Ba, and Sb were quantified in cases 1 and 2 with a concentration of 6.28 and 1.78 μg/g for Pb, 1.49 and 2.94 μg/g for Ba, 0.50 μg/g and <LD for Sb, respectively. These new results present the detection of characteristic elements of GSR in cadaveric larvae in humans in a real crime scene, besides highlighting the importance of the study of immature flies, using the ICP-MS technique in forensic analysis.  相似文献   
157.
This article uses the concept of entrepreneurial powers to discuss how and under what circumstances Brazil successfully accomplishes its goals in international crises. The concept of entrepreneurial power focuses on systematic evidence of middle‐power behavior and its relation to foreign policy tools. Brazil resorts to three agency‐based foreign policy tools that are the substance of its entrepreneurial power. These instruments are always mediated by a structural condition, the dominant power pivotal position in the crisis. This study applies qualitative comparative analysis methodology to 32 international crises since the early 1990s in which Brazil played a role. It finds that for regional crises, the use of only one agency‐based tool is sufficient for success, regardless of the dominant power position; and for global crises, the use of only one agency‐based tool is a necessary and sufficient condition for Brazil to accomplish its goals, despite the dominant power position on the issue.  相似文献   
158.
159.
This investigation intends to study materials and techniques used for biological evidence collection in sexual assault cases and is divided into two stages: in stage one, methods for biological evidence collection (the single swab (including three variants) and the “double swab technique”) were compared; in stage two, swabs’ component material was compared. The sampling was composed of 42 heterosexual couples who provided mock samples. The collection methods in which the whole swab is covered by evidence presented significantly better outcomes (< 0.001), such as the “double swab technique.” Additionally, nylon swabs proved to present significantly better features regarding the capacity of sample elution, providing significantly higher amounts of DNA ( 0.034). This study provides guidelines for better collection of biological evidence regarding the collection method using a swab and the proper swab material to utilize.  相似文献   
160.
Self-Report Delinquency scales have formed the basis of much understanding of juvenile delinquency today, but further improvement and extensive measurement research on self-report measures of crime are needed. The present study examined the psychometric properties of the shorter general delinquency scale version of the classic commonly used Self-Report of Delinquency (SRD) measure created for the original National Youth Survey (NYS) using a sample (N = 412) of male (n = 200) and female (n = 212) at-risk Portuguese youths. The shorter version of the SRD demonstrated satisfactory validity and reliability, namely in terms of its latent one-factor structure, internal consistency, convergent validity, divergent validity, concurrent criterion validity and discriminant groups validity that overall justifies its use among this population. The shorter general delinquency scale version of the SRD is a valid and reliable measure from a modern psychometric perspective that can be used with at-risk youths.  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