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131.
The identification of sex from the skeleton is an important demographic assessment in medicolegal investigations. Rama Purkait developed a method for estimating sex using measurements from a triangle defined by three points on the proximal end of the femur using skeletal material from Bhopal, India. This method was tested with measurements on 200 Indo-European and African American adult femora from the Terry collection using discriminant function analysis to determine if Purkait's method was valuable for determining sex in Americans. A side-by-side analysis was conducted of Purkait's "triangle method" and the maximum diameter of the femoral head to determine their relative value in assessing sexual dimorphism. In the study sample a single variable from Purkait's method provided 85.5% prediction accuracy, similar to 87% for the head diameter. Combining threshold values for a single variable from Purkait's method and the femoral head diameter raised the predictability to greater than 90% for both sexes. 相似文献
132.
目的探讨小鼠皮肤切创愈合过程中损伤区磷酸化p38MAPK(p-p38MAPK)的表达情况,以及不同损伤时间p-p38MAPK的变化规律。方法应用免疫组织化学和Westernblot的方法检测33例小鼠皮肤切创后各个时间段p-p38MAPK表达情况。结果正常组织中有少量的p-p38MAPK表达。伤后3~12h损伤区p-p38MAPK主要表达于中性粒细胞中,1~5dp-p38MAPK阳性表达主要为单核细胞和成纤维细胞。7~14dp-p38MAPK阳性表达主要以成纤维细胞为主。阳性细胞率3~12h逐渐升高,1d有所下降,3、5d阳性细胞率保持在高水平,7~14d阳性细胞率逐渐降低。Westernblot显示各个时间段均有p-p38MAPK的表达。其中12h和3d为2个p-p38MAPK含量的高峰。结论在小鼠切创愈合过程中p-p38MAPK在损伤区对诱导中性粒细胞、单核细胞和成纤维细胞的凋亡起重要的作用,同时p-p38MAPK的规律性表达可用于损伤时间的推断。 相似文献
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134.
摘要:本文简析了“韬光养晦”外交战略的历史与现实,并结合《孙子兵法》的相关论述,指出中国必须全面审视、理解和坚持“韬光养晦”策略,并要正确认识到“韬光养晦”相较于一种手段更是一种价值。该文认为,破除激进主义的简单思维,破除盛世的迷梦,冷静地正视,有效地反击,运用东方文明的智慧,从而最大限度地突破围堵,为国家的和平发展营造最佳的战略环境,才是当前中国外交战略的根本所在。 相似文献
135.
犯罪均值频率——一种犯罪时间分布的测度指标 总被引:1,自引:0,他引:1
犯罪在时间分布方面有其特定规律,常规的犯罪总数或平均数等统计量存在不稳定性、偏差性和数据保密性等问题,不利于犯罪时间分布特征的客观对比分析。犯罪均值频率指标克服了传统时间分布统计量存在的问题,可以用来分析犯罪是否偏好发生于特定的时间内,满足了犯罪时间分布规律分析需求。运用该指标对某市5年内的入室盗窃犯罪在星期日别、月份上的时间分布规律进行了实证研究,结果表明,入室盗窃在该市3月份和9-12月份表现为高发期,而在周末则表现为犯罪低谷期。 相似文献
136.
Schäffer M Gröger T Pütz M Dieckmann S Zimmermann R 《Journal of forensic sciences》2012,57(5):1181-1189
Abstract: The chemical profiling of illicit drugs is an important analytical tool to support the work of investigating and law enforcement authorities. In our work, comprehensive two‐dimensional gas chromatography–time‐of‐flight mass spectrometry (GC × GC‐TOFMS) combined with nontargeted, pixel‐based data analysis was adapted for the chemical profiling of 3,4‐methylenedioxymethamphetamine (MDMA). The validity and benefit of this approach was evaluated by analyzing a well‐investigated set of MDMA samples. Samples were prepared according to a harmonized extraction protocol to ensure the comparability of the chemical signatures. The nontargeted approach comprises preprocessing followed by analysis of variances as a fast filter algorithm for selection of a variable subset followed by partial least squares discriminant analysis for reduction to promising marker compounds for discrimination of the samples according to their chemical profile. Forty‐seven potential marker compounds were determined, covering most of the target impurities known from the harmonized one‐dimensional profiling as well as other compounds not previously elucidated. 相似文献
137.
138.
Abstract: The quality and efficiency of a standard organic DNA isolation method and a silica‐based method using the QIAGEN Blood Maxi Kit were compared to obtain human DNA and short tandem repeats (STRs) profiles from 39 exhumed bone samples for paternity testing. DNA samples were quantified by real‐time PCR, and STR profiles were obtained using the AmpFlSTR® Identifiler® PCR amplification kit. Overall, the silica‐based method recovered less DNA ranging from 0 to 147.7 ng/g (average 7.57 ng/g, median = 1.3 ng/g) than did the organic method ranging from 0 to 605 ng/g (average 44.27 ng/g, median = 5.8 ng/g). Complete profiles (16/16 loci tested) were obtained from 37/39 samples (95%) using the organic method and from 9/39 samples (23%) with the silica‐based method. Compared with a standard organic DNA isolation method, our results indicate that the published silica‐based method does not improve neither the quality nor the quantity of DNA for STR profiling. 相似文献
139.
This case study illustrates the use of the date function on an automatic wristwatch to help identify a Vietnam War helicopter crash site. The location of a crash incident can sometimes be uncertain because of inadequate or inaccurate wartime records and the passage of time. Artifacts recovered from a prospective crash scene are regularly used to correlate the loss incident. In this case study, a recovered automatic watch displayed a date 2 days later than the reported loss incident. Although the date conflicts with the aircraft crash incident report, it is observed that a fully wound automatic watch continues to work for c. 2 days after movement of the watch ceases. Thus, the watch's date in fact correlates with the aircraft crash incident report. It is noted that automatic watches may also be used to date scenes of crime. 相似文献
140.
Lee UY Han SH Park DK Kim YS Kim DI Chung IH Chun MH 《Journal of forensic sciences》2012,57(1):166-171
The aims of this study were to investigate the sex discriminating potential of the talus in Koreans and compare this with other analyses in different populations. Statistical analyses were performed using data from nine measurements acquired from 140 tali (70 men, 70 women). The talus of Koreans is dimorphic between sexes in all measurements (p < 0.01). Discriminant function equations were generated by univariate, multivariate, and stepwise methods with a range of accuracy from 67.1 to 87.1%. Stepwise equations of other populations did not discriminate the sex of the Korean sample as accurately as each equation's own accuracies. The variables with high accuracy in this study are useful for sex determination of Koreans on the basis of confirmation of population specificity. 相似文献