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51.
利用积温和昆虫发育历期推测死亡时间的研究 总被引:2,自引:0,他引:2
目的积累尸食性蝇类虫态发育历期和积温的资料。方法采用动物尸体作诱饵,分别对自然飞到诱饵上繁殖生长的6种尸食性蝇类的虫态发育历期和积温进行观察研究。结果经过观察,取得了棕尾别麻蝇、丝光绿蝇、紫绿蝇、宽丽蝇、巨尾阿丽蝇、大头金蝇等6种尸食性蝇类的虫态发育历期和积温的基础数据。并采用倒计积温的方法推测实际案例中死者死亡时间,破案后证实推测时间与实际死亡时间一致。结论本文数据可为利用尸食性蝇类虫态育历期的积温推测死亡时间提供依据。 相似文献
52.
大鼠弥漫性脑损伤后早期病理学及烯醇化酶表达 总被引:2,自引:0,他引:2
目的观察烯醇化酶(NSE)在弥漫性脑损伤(DB I)动物模型中的变化。方法采用M arm arou的弥漫性脑损伤模型,于伤后15m in,30m in,1h,3h,6h,12h,24h取脑组织,运用免疫组化SABC法染色结合北航MAIS图像分析系统进行图像分析。结果打击后15m in,阳性细胞灰度值较正常对照组减弱,随伤后时间的延长,灰度值持续下降,伤后6h为最低(P<0.01),伤后24h仍显著低于正常对照组。伤后12h阳性细胞数明显减少(P<0.01),并持续到伤后24h。特殊染色观察到轴突断端球形改变及神经纤维脱髓鞘改变。结论DB I具有复杂的病理学改变,烯醇化酶(NSE)可用于早期鉴定及损伤经过时间的推断。 相似文献
53.
从近几年的冬季征兵、夏季特招士官和军校高招来看,当代青年再现应征参军热潮。这其中无论是普通社会青年,还是莘莘学子,促成其崇尚参军报国的深层背景中,有个人长期的军旅夙愿和传统的爱国情怀,也有国庆阅兵等时事宣传,以及"大学生好兵高明"的示范效应,更有国家新出台的对大学生入伍优惠政策等外部因素,是全社会共同营造的良性氛围点燃了这种热切与激情。 相似文献
54.
在兴边富民行动开展10周年之际,评估兴边富民行动的实施效果具有重大的理论和现实意义。本文利用内蒙古边境旗市统计数据定量分析了兴边富民行动的实施效果。回归结果表明,总体而言内蒙古兴边富民行动实施效果并不令人满意,尽管第二产业获得加速发展,公路建设成效显著,也促进了边境地区的商品贸易,但基本上没有实现加速当地经济发展、加快改善农牧民生活水平的目的,而且卫生事业发展相对落后。 相似文献
55.
56.
《崇陵传信录》是常被有关论著征引的一部著名私家笔记。长期以来,人们一直认其成书时间在满清退位以前,所据为恽毓鼎在本书的"弁言"后署时"宣统三年辛亥四月"。其实,这是恽毓鼎的故弄玄虚。真实情况是,该书于1912年8月6日开笔,随即又搁置下来,直至次年9月22日才脱稿。此中原委,今借助恽毓鼎《澄斋日记》的有关记录得以弄清楚。另外,梁启超、罗惇融、饶智元等人与该书在有关报刊的连载及一次性全文发表均有关系,但长期以来鲜有提及者。 相似文献
57.
This study evaluated the use of different degree day (DD) models, developmental thresholds and developmental data sources for estimating postmortem interval (PMI) based on developmental rates of blow flies (Diptera: Calliphoridae). Blow fly evidence was collected from three mock crime scenes and sent for blind analysis of PMI. PMI estimates were calculated using averaging, single sine, double sine, single triangle, and double triangle models of DD calculation with minimum developmental thresholds of 0, 6 and 10 °C and Anderson's, Byrd and Allen's, Greenberg's, Nishida's and Kamal's developmental data sets. These estimates were compared with the actual PMI to determine which combination of DD model, developmental threshold and developmental data provided the most accurate estimate. For all three cases, at least one method gave a PMI estimation that was within 1 day of the actual date of death. There was no variability between PMI estimated using the five models of DD calculation. Overall, as lower developmental threshold increased, the PMI interval estimates increased. Depending on the developmental data set used, increasing the lower developmental threshold caused some overestimations of the date of oviposition, with estimates given that were prior to the actual death. Future PMI estimates should include error ranges, so that overestimation of PMI is avoided. 相似文献
58.
Survival analysis: A survey 总被引:1,自引:0,他引:1
This paper is a survey of statistical methods used to analyze the length of time until a specified event occurs. These models have often been used to analyze the survival times (i.e., time until death) of medical patients, and so the term survival analysis is natural. In criminology, the main application of these models has been to analyze the time until recidivism, but many other applications are possible. The paper summarizes the statistical literature on survival analysis, and describes its applications in criminology. The methods are illustrated by an application to the prediction of time until recidivism for a sample of North Carolina prison releasees. 相似文献
59.
Abstract: A new screening method for detecting gamma-hydroxybutyric acid (GHB) in drink matrices, using the IonSense, Inc. (Saugus, MA) direct analysis in real time (DART) ion source coupled to a JEOL exact mass time-of-flight mass spectrometer (AccuTOF), was validated and compared with the current screening methodology. The DART ion source allows for analysis of samples under ambient conditions with little to no sample preparation. Fifty drink specimens were spiked at levels of 1, 2, 3, and 4 mg/mL GHB, and analyzed on the AccuTOF-DART. Positive detection of GHB occurred for each of the samples at each concentration level, giving 100% accuracy for the samples tested. Twenty-five of the 50 drink specimens were spiked at 1 mg/mL GHB and tested using a color test known as the GHB Color Test #3. Only two of these 25 specimens tested positive for the presence of GHB, giving only 8% accuracy. Implementation of this new methodology as a screening tool for GHB analysis will quickly eliminate negative specimens allowing the examiner to focus analysis time on those that screened positive. 相似文献
60.
William Rhodes 《Journal of Quantitative Criminology》1986,2(2):113-137
Researchers are frequently interested in estimating the elapsed time until the occurrence of an event, such as an arrest following release from prison, dissolution of a marriage, and death following the onset of a disease. Estimation is often hindered by the occurrence of a competing event, which prevents the event of interest from being observed, and by limited follow-up periods. A parametric procedure developed in this paper is suitable for dealing with nonrepeatable competing events when the events are correlated and when independent righthand censoring also exists. Weak distributional assumptions are accommodated by using a Box-Cox transformation and by explicit modeling of heteroscedasticity. The procedure is applied to data pertaining to failure on probabation and parole. 相似文献