1案例资料例1某男,40岁。某年10月在铁路线上背向蹲位吸烟时被火车撞碾致死。尸体位于线路中心,撞击点与尸体相距约5m,其间的石枕中部端楞上有间断的、向火车运行方向擦蹭的血迹,个别石枕上附着有多根毛发。死者上身衣着由下向上翻卷至颈部,并有明显的擦蹭痕迹。外裤前侧膝部有明显纵行磨擦痕迹及多 Case data example 1 a man, 40 years old. One year in October on the railway line back to squatting smoking was hit by a train crash grind to death. The body is located in the center of the line, the impact point and the body about 5m, during which the middle of the stone pillow on the end of the intermittent, rubbing the blood to the direction of the train running, individual stone pillow attached to the hair. The dead corset rolled up from the bottom to the neck, and there are obvious signs of rubbing. Pants on the front knee obvious longitudinal friction marks and more