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231.
Estimation of age in individuals has received considerable attention in forensic science, in which it is a widely used method for individual identification, together with paleo-demographic analyses to establish mortality patterns in past populations. The present investigation, which is a continuation of a previously published pilot study, was conducted to examine the possible application of the pulp/tooth area ratio by peri-apical images as an indicator of age at death. A total of 200 peri-apical X-rays of upper and lower canines were assembled from 57 male and 43 female skeletons of Caucasian origin, aged between 20 and 79 years. They belong to the Frassetto osteological collection of Sassari (Sardinia) and are housed in the Museum of Anthropology, Department of Experimental and Evolutionistic Biology, University of Bologna. For each skeleton, dental maturity was evaluated by measuring the pulp/tooth area ratio on upper (x(1)) and lower (x(2)) canines. Very good agreement was found between intraobserver measurements. Statistical analysis was performed in order to obtain multiple regression formulae for dental age calculation, with chronological age as dependent variable, and gender, and upper and lower canines as independent variables. Stepwise regression analysis showed that gender did not contribute significantly to the fit (p=0.881) whereas variables x(1) and x(2) and the first-order interaction between them did. These two variables explained 92.5% of variations in estimated chronological age and the residual standard error was 4.06 years. Lastly, two simple linear regression equations were obtained for age estimation using canines from the maxilla and mandible separately. Both models explained 86% of variations in estimated chronological age and allowed an age-at-death estimate with a residual standard error of about 5.4 years.  相似文献   
232.
Changes in the size of the pulp canal, caused by apposition of secondary dentine, are the best morphometric parameters for estimating age by X-rays. The apposition of secondary dentine is the most frequently used method for age estimation in adult subjects. In two previous papers, we studied the application of the pulp/tooth area ratio by peri-apical X-rays as an indicator of age at death. The aim of the present study was to test the accuracy of age evaluation by combined analysis of labio-lingual and mesial peri-apical X-rays of lower and upper canines. A total of 200 such X-rays were assembled from 57 male and 43 female skeletons of Caucasian origin, aged between 20 and 79 years. For each skeleton, dental maturity was evaluated by measuring the pulp/tooth area ratio according to labio-lingual and mesial X-rays on upper (x(1), x(2)) and lower (x(3), x(4)) canines. Very good agreement was found between intra-observer measurements. Statistical analysis showed that all variables x(1), x(2), x(3), and x(4) and the first-order interaction between x(1) and x(3) contributed significantly to the fit, so that they were included in the regression model, yielding the following regression formula: Age = 120.737 - 337.112x(1) - 79.709x(2) - 364.534x(3) - 65.655x(4) + 1531.918x(1)x(3) . The residual standard error of estimated ages was 3.62 years, with 94 degrees of freedom, and the median of the residuals was -0.155 years, with an interquartile range of 4.96 years. The accuracy of the method was ME = 2.8 years, where ME is the mean prediction error. The model also explained 94% of total variance (R(2) = 0.94).  相似文献   
233.
Abstract:  Human scent evidence is utilized as an investigative tool through canine scent discriminations based on the premise that human scent is an individualizing characteristic. This study describes the development of what is effectively a human scent barcode consisting of the relative ratios of an individual's "primary odor" compounds utilized to determine a reproducible and individualizing profile which can be stored in a searchable database for a proof of concept of human scent as a biometric measure. Triplicate hand odor samples were evaluated from 10 subjects utilizing solid phase micro-extraction gas chromatography/mass spectrometry (SPME-GC/MS) and compared via Spearman Rank Correlations. Narrowing the compounds considered for each subject to only those common in all three samples, or a subject's "primary odor constituents," produced a greater degree of both individualization and discrimination; at both correlation thresholds of 0.9 and 0.8, the individuals were correctly discriminated and identified in 99.54% of the cases.  相似文献   
234.
Abstract: We investigated toxicological and pharmacogenetic factors that could influence methadone toxicity using postmortem samples. R‐ and S‐methadone were measured in femoral blood from 90 postmortem cases, mainly drug users. The R‐enantiomer concentrations significantly exceeded that of the S‐enantiomers (Wilcoxon’s test, p < 0.001). The samples were divided into four groups according to other drugs detected (methadone only, methadone and strong analgesics, methadone and benzodiazepines, or methadone and other drugs). There was no significant difference in any of the R‐methadone/total methadone ratios among the four groups. The median R/S ratio was 1.38, which tends to be higher than that reported for the plasma of living subjects. In addition, we investigated whether small nucleotide polymorphisms in the MDR1 gene that encode the drug transporter P‐glycoprotein were associated with the concentrations of R‐ and S‐methadone and its metabolite 2‐ethylidene‐1,5‐dimethyl‐3,3‐diphenylpyrrolidine. No significant association was detected.  相似文献   
235.
目的建立血、肝组织中芬太尼和舒芬太尼的HPLC-MS/MS分析方法。方法采用Oasis(MCX固相萃取柱进行提取,以XTerraTMRP18柱(2.1mm×100mm,3.5μm)色谱柱分离,以乙腈∶5mmol/L醋酸铵水溶液(氨水调pH=9.5)(65∶35)为流动相,流速为0.2mL/min。结果血及肝组织添加样品的线性范围为10ng/mL~500ng/mL,最小检出限为0.1ng/mL。结论本方法准确、快速,可用于生物检材血、肝组织中芬太尼和舒芬太尼的定性定量分析。  相似文献   
236.
目的利用GC/MS、GC/NPD与固相萃取(SPE)技术相结合,建立血液中苯丙胺类毒品的定性定量分析方法。方法采用Bond—ElutCerti{y固相柱、甲醇淋洗、二氯甲烷/异丙醇/氨水(78/20/2)洗脱固相萃取分离提取,比较了不同PH体系、稀释状态、洗脱溶剂对提取回收率的影响,建立血液中苯丙胺类毒品的GC/MS、GC/NPD定性定量分析方法。结果以GC/NPD分析AM、MA、MDA和MDMA浓度在15ng/mL-2000ng/mL、10ng/mL~1600ng/mL、20ng/mL-3000ng/ml、20ng/mL-3000ng/mL范围内线性关系良好,AM、MA、MDA和MDMA的检测限分别为10ng/mL、8ng/mL、15ng/mL、15ng/mL,方法平均回收率大于85%,标准偏差小于5%,GC/MS-Scan检测限分别为40ng/mL、32.0ng/mL、60.0ng/mL、60.0ng/mL。结论此方法可满足苯丙胺类毒品滥用者的血液定性定量分析。  相似文献   
237.
近几年,公安网交通管理业务处理实现了信息化,如何将公安网交通管理信息系统相关功能实时、安全延伸至路面执勤交警,实现路面执勤交警执法处理工作的信息化成了急待解决的问题。为此,各地投入大量人力、物力研究和推广应用交警专用移动执法系统。但现有系统在功能可用性和全面性、系统安全设计等方面存在较大问题,影响了系统的深入应用。本文根据各地交警专用移动执法系统存在的问题,针对性地提出了总体研究和设计方案,对提高各地交警专用移动执法系统的研究设计水平有很好的指导作用。  相似文献   
238.
第十八届国际艾滋病会议于2010年7月在维也纳召开。会议主要讨论了同性恋、性工作和吸毒非罪化问题及关于艾滋病强制检测、艾滋病隐私和艾滋病传播犯罪问题。此外,有可能开发成功降低艾滋病感染风险的药物和有效预防艾滋病的疫苗。中国代表团参加会议并介绍了我国艾滋病防治的情况。  相似文献   
239.
This article attempts to measure the direct costs that the terrorist attacks of 3/11 had on the economy of the region of Madrid. The evaluation has been made applying conservative criteria, and the results obtained have to be considered as minimum. The result indicates that the terrorist attacks caused a loss of nearly 212 million euros to the regional economy of Madrid, equivalent to 0.16 percent of the regional GDP (0.03 of the national GDP). This confirms that the immediate economic dimension of a terrorist attack such as the one of 3/11—apart from human catastrophic consequences—is relatively low.  相似文献   
240.
为了提高转移因子的稳定性,以壳聚糖和海藻酸钠为囊材,采用乳化外部凝胶法制备猪脾转移因子微囊,并检测了其粒径大小、包封率、载药量等性质;通过小鼠腹腔巨噬细胞吞噬试验和迟发型超敏反应试验检测转移因子微囊的药理活性。结果显示,转移因子微囊呈类圆形,平均粒径为11.05μm,包封率为60.8%,载药量11.60mg/g;转移因子微囊能增强小鼠腹腔巨噬细胞的吞噬功能,提高迟发型超敏反应的能力,效果优于转移因子。结果表明,该制备工艺简单,转移因子微囊具有较好的发展前景。  相似文献   
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