大鼠肌肉电导率测定与死亡时间的推断  

Determination of the electrical conductivity of rat muscle and estimation of postmortem interval

作　　者：夏志远[1] 翟仙敦[1] 刘蓓蓓[1] 莫耀南[1] 

机构地区：[1]河南科技大学法医学院,河南洛阳471003

出　　处：《中国法医学杂志》2015年第6期574-578,共5页Chinese Journal of Forensic Medicine

基　　金：河南省基础与前沿课题(112300410082);河南科技大学基金资助项目(09001309;13000914;13000696)

摘　　要：目的探讨大鼠肌肉电导率(electrical conductivity,EC)与死后经历时间(postmortem interval,PMI)的关系,为EC用于现场PMI的快速推断提供实验依据。方法 48只健康大鼠,随机分成16组,每组3只,颈部脱臼处死后保存在19℃±1℃环境中,于不同PMI提取肌肉样本,并用超纯水以1g:10m L制备浸渍液,并在25℃、20℃和18℃环境下检测EC值。浸渍液稀释不同浓度后,再次检测其EC值。分析不同温度浸渍液EC差异,并计算温度补偿系数(TCC);分析不同浓度浸渍液EC与稀释倍数的关系;分析浸渍液EC(25℃)与PMI的关系。结果 EC温度补偿系数α=2.0%/℃;不同稀释浓度浸渍液EC与稀释比例之间存在严格的二次相关性(R2=1)。浸渍液EC在24h内随PMI变化不明显,而24h后变化显著,拟合三次回归方程为y=-0.01x3+0.264x2-13.657x+1 769.148(R2=0.925)。结论肌肉浸渍液EC的测定方法准确、简便、快速,可能成为现场晚期尸体死亡时间推断的新方法。Objective To investigate the relationship between electrical conductivity （EC） of rear muscle and postmortem interval （PMI） in order to offer laboratory evidences for further application of EC in rapid estimation of PMI at scene. Methods Forty-eight healthy Sprague-Dawley rats being divided randomly into 16 groups （3 each group） were killed by cervical vertebrae dislocation and kept at 19℃±1℃. Muscle samples were acquired at different PMIs and their extraction liquids were prepared with ultrapure water at the ratio of lg： 10ml. The EC values at different PMI were determined in the liquids at 25℃, 20℃ and 18℃. After extraction liquids were diluted into different concentrations, EC values were determined again in the new diluents. The EC difference of extraction liquids at different temperatures was analyzed and temperature compensation coefficients （TCCs） were calculated. Then it was analyzed to the relationship between the EC of extraction liquids and their dilution multiples, and between the EC of extraction liquids at 25℃ and PMI. Results Temperature compensation coefficient （TCC）of EC was 2.0%/℃. There was strict quadratic correlations （R^2 = 1 ） between EC of different multiple diluents of same liquid samples and their dilution ratios. The EC changed insignificantly with PMI within 24h but significantly after 24h. The regression equation was y = - 0.01 x^3 ＋ 0. 264x^2 - 13. 657x ＋ 1 769. 148 （R^2 = 0. 925 ）. Conclusion EC detection of muscle extraction liquids is accuract, simple and rapid and it is expected to become a new method for estimation of postmortem interval to the late dead body at scene.

关 键 词：法医病理学 死亡时间 死亡时间推断 电导率 浸渍液 

分 类 号：D919[医药卫生—法医学]