Karger B, Rand S P, Brinkmann B
Institut für Rechtsmedizin, Westfälische Wilhelms-Universität, Münster, Germany.
Int J Legal Med. 1998;111(1):17-21. doi: 10.1007/s004140050104.
The differentiation between contact bloodstains and stains produced by projected droplets on fabric can be crucial in crime scene reconstruction since suspects can explain bloodstains on their clothing by contact with the victim post mortem. Experimental smear and contact pressure stains on three different types of fabric were compared with stains produced by falling and projected droplets ("dynamic" stains) of equivalent size. The morphology of the small stains (0.1-10 microliters) was investigated with a macroscope. Characteristic for "dynamic" stains are symmetry and rhythmicity (secondary droplets) of the stain and a zonal drying pattern. Contact stains lack the characteristic features of "dynamic" stains and show a clear impregnation of the material resulting in a blood-soaked reverse side of cambric and cotton and in a paler overall colour. The mode of formation of microstains (blood volume 1 < microliter) on irregular surfaces (e.g. terry cloth) can be difficult to determine since the rough surface structure and the small blood volume reduce the characteristics of dynamic stains. In these cases, comparison with experimental stains on the same surface material is recommended.
在犯罪现场重建中，区分织物上的接触血迹和抛洒血滴形成的血迹至关重要，因为嫌疑人可能会解释其衣物上的血迹是在受害者死后与其接触所致。将三种不同类型织物上的实验性涂抹血迹和接触压力血迹，与同等大小的坠落和抛洒血滴（“动态”血迹）形成的血迹进行了比较。用体视显微镜研究了小血迹（0.1 - 10微升）的形态。“动态”血迹的特征是血迹具有对称性和节律性（次生血滴）以及带状干燥模式。接触血迹缺乏“动态”血迹的特征，且会使材料明显浸染，导致细薄布和棉布的背面被血浸透，整体颜色变浅。在不规则表面（如毛巾布）上形成微血迹（血量小于1微升）的方式可能难以确定，因为粗糙的表面结构和少量的血量会降低动态血迹的特征。在这些情况下，建议与相同表面材料上的实验血迹进行比较。
