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   249篇
  免费   11篇
各国政治   20篇
工人农民   18篇
世界政治   23篇
外交国际关系   14篇
法律   99篇
政治理论   83篇
综合类   3篇
  2023年   2篇
  2022年   3篇
  2021年   3篇
  2020年   6篇
  2019年   7篇
  2018年   9篇
  2017年   8篇
  2016年   11篇
  2015年   6篇
  2014年   14篇
  2013年   46篇
  2012年   2篇
  2011年   9篇
  2010年   2篇
  2009年   5篇
  2008年   4篇
  2007年   12篇
  2006年   6篇
  2005年   5篇
  2004年   7篇
  2003年   6篇
  2002年   9篇
  2001年   4篇
  2000年   6篇
  1999年   6篇
  1998年   2篇
  1995年   3篇
  1994年   4篇
  1993年   4篇
  1992年   2篇
  1991年   1篇
  1990年   2篇
  1989年   1篇
  1988年   3篇
  1987年   6篇
  1986年   3篇
  1985年   3篇
  1984年   3篇
  1983年   2篇
  1982年   3篇
  1981年   1篇
  1980年   2篇
  1979年   3篇
  1978年   3篇
  1977年   2篇
  1976年   1篇
  1974年   3篇
  1973年   2篇
  1972年   1篇
  1971年   1篇
排序方式: 共有260条查询结果,搜索用时 15 毫秒
191.
192.
The importance of identification using the frontal sinus has been previously demonstrated in case reports. In this study, 39 cases of identification using frontal sinus comparison from the Ontario Chief Coroner's Office were reviewed and differences between antemortem and postmortem radiographs examined. All cases involved decedents older than twenty years. Three cases were rejected due to poor antemortem and postmortem film quality. One subject had no frontal sinus. Thirty-five cases provided conclusive postmortem to antemortem pattern matches. Sixteen cases also yielded metric (quantitative) matches. Duration between antemortem and postmortem radiographic examinations, age, gender, and cause of death did not affect the ability to obtain a match. This is the largest study undertaken on actual cases and demonstrates the validity of frontal sinus pattern matching for forensic identification.  相似文献   
193.
194.
195.
196.
This paper reports a bilaterally symmetrical cranio-facial fracture pattern that is observed in self-inflicted, midline gunshot wounds. Five cases of self-inflicted gunshots wounds are presented as follows: two high-powered rifle cases, two shotgun cases, and one handgun case. In all five cases the remains were either decomposing or skeletonized and submitted to forensic anthropologists. Following identification, the main focus of the anthropological examination was the analysis of perimortem trauma to the skeleton. In each case, the skull was submitted in a highly fragmented state. Nevertheless, by focusing on the pattern of perimortem cranio-facial fractures, the anthropologists contributed key information regarding the circumstances of death. The observed symmetrical cranio-facial fracture patterns in the above cases are described in detail and interpreted. The specific location of the linear fractures is discussed, as well as the theoretical rationale behind the location in terms of skeletal architecture, such as buttresses, struts, and sutures. The interpretive framework provided by this paper may prove helpful to others who are faced with similar cases of cranio-facial fracturing.  相似文献   
197.
We present a validated method for the simultaneous analysis of basic drugs which comprises a sample clean-up step, using mixed-mode solid-phase extraction (SPE), followed by LC-MS/MS analysis. Deuterated analogues for all of the analytes of interest were used for quantitation. The applied HPLC gradient ensured the elution of all the drugs examined within 14 min and produced chromatographic peaks of acceptable symmetry. Selectivity of the method was achieved by a combination of retention time, and two precursor-product ion transitions for the non-deuterated analogues. Oral fluid was collected with the Intercept, a FDA approved sampling device that is used on a large scale in the US for workplace drug testing. However, this collection system contains some ingredients (stabilizers and preservatives) that can cause substantial interferences, e.g. ion suppression or enhancement during LC-MS/MS analysis, in the absence of suitable sample pre-treatment. The use of the SPE was demonstrated to be highly effective and led to significant decreases in the interferences. Extraction was found to be both reproducible and efficient with recoveries >76% for all of the analytes. Furthermore, the processed samples were demonstrated to be stable for 48 h, except for cocaine and benzoylecgonine, where a slight negative trend was observed, but did not compromise the quantitation. In all cases the method was linear over the range investigated (2-200 microg/L) with an excellent intra-assay and inter-assay precision (coefficients of variation <10% in most cases) for QC samples spiked at a concentration of 4, 12 and 100 microg/L. Limits of quantitation were estimated to be at 2 microg/L with limits of detection ranging from 0.2 to 0.5 microg/L, which meets the requirements of SAMHSA for oral fluid testing in the workplace. The method was subsequently applied to the analysis of Intercept samples collected at the roadside by the police, and to determine MDMA and MDA levels in oral fluid samples from a controlled study.  相似文献   
198.
199.
200.
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