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   219篇
  免费   14篇
各国政治   2篇
工人农民   3篇
世界政治   6篇
外交国际关系   3篇
法律   96篇
中国共产党   10篇
中国政治   15篇
政治理论   11篇
综合类   87篇
  2023年   3篇
  2022年   2篇
  2021年   7篇
  2020年   7篇
  2019年   2篇
  2018年   9篇
  2017年   3篇
  2016年   5篇
  2015年   3篇
  2014年   14篇
  2013年   15篇
  2012年   11篇
  2011年   10篇
  2010年   18篇
  2009年   20篇
  2008年   14篇
  2007年   19篇
  2006年   15篇
  2005年   17篇
  2004年   8篇
  2003年   11篇
  2002年   7篇
  2001年   6篇
  2000年   4篇
  1999年   2篇
  1988年   1篇
排序方式: 共有233条查询结果,搜索用时 15 毫秒
231.
At outdoor crime scenes, cadaver-detection and blood-detection dogs may be tasked with locating blood that is days, weeks or months old. Although it is known that the odour profile of blood will change during this time, it is currently unknown how the profile changes when exposed to the environment. Such variables must be studied in order to understand when the odour profile is no longer detectable by the scent-detection dogs and other crime scene tools should be implemented. In this study, blood was deposited onto concrete and varnished wood surfaces and weathered in an outdoor environment over a three-month period. Headspace samples were collected using solid phase microextraction (SPME) and analysed using comprehensive two-dimensional gas chromatography – time-of-flight mass spectrometry (GC×GC–TOFMS). The chemical odour profiles were compared with the behavioural responses of cadaver-detection and blood-detection dogs during training. Data interpretation using principal component analysis (PCA) and hierarchical cluster analysis (HCA) established that the blood odour could no longer be detected using SPME–GC×GC–TOFMS after two months of weathering on both surfaces. Conversely, the blood-detection dogs had difficulty locating the blood samples after one month of weathering on concrete and after one week of weathering on varnished wood. The scent-detection dogs evaluated herein had not been previously exposed to environmentally weathered blood samples during training. Given that this study was conducted to test the dogs' baseline abilities, it is expected that with repeated exposure, the dogs' capabilities would likely improve. The knowledge gained from this study can assist in providing law enforcement with more accurate training aids for blood-detection dogs and can improve their efficiency when deployed to outdoor crime scenes.  相似文献   
232.
主诉检察官制度赋予主诉检察官较大的职权 ,建立主诉检察官的内部管理监督机制是对主诉检察官权力的制约。本文阐述了建立主诉检察官内部管理监督机制的原则及其具体制度  相似文献   
233.
We explore the strategies implemented by Research Groups' Leaders while coping with unstable contexts, characterized by incoherence and lack of coordination among different policy discourses and instruments, and scarce resources. We focus on a country where these conditions are present: Colombia. In doing so, we study two cases, one in nanotechnology and another one in biomedical engineering. Interviews, focus groups and workshops allowed us to identify and validate strategies grouped in four popular sayings, proper to local idiosyncrasy, highlighting the role of home institutions and principal investigators in facing such situations with resilience and resourcefulness, and even taking advantage of them. We find that Research Groups' Leaders use strategies such as: adapting, balancing agendas and funding sources, networking, and taking advantage of the support programs available at their home institution to continue functioning. These are setting the ground for a further survey which could pretend some generalization. However, policymakers could consider these findings when defining policy instruments or for assessing their effectiveness or impacts.  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