无明显电流斑电损伤鉴定的研究进展

低压电电击死的法医学鉴定在形态上主要依据皮肤电流斑来确定,但在实际工作中尚有电流斑不明显,甚至缺如的案例,使鉴定工作产生一定难度.本文依据文献资料对电击伤的机制及无明显电流斑的电损伤的各种相关指标进行综述。     

无明显电流斑电损伤鉴定的研究进展

低压电电击死的法医学鉴定在形态上主要依据皮肤电流斑来确定，但在实际工作巾尚有电流斑不明显，甚至缺如的案例．使鉴定工作产生一定难度．本文依据文献资料对电击伤的机制及无明显电流斑的电损伤的各种相关指标进行综述。     

傅里叶变换显微红外光谱结合机器学习算法鉴定电击伤

目的基于傅里叶变换显微红外光谱结合机器学习算法分析猪皮肤电击伤、烧伤及擦伤的差异,构建3种皮肤损伤鉴定模型,筛选电击伤特征性标志物,为皮肤电流斑鉴定提供新方法。方法建立猪皮肤电击伤、烧伤及擦伤的模型,使用传统HE染色检验不同损伤的形态学改变。运用傅里叶变换显微红外技术检测表皮细胞光谱,运用主成分、偏最小二乘法分析损伤的分类情况,运用线性判别和支持向量机构建分类模型,因子载荷筛选特征性标志物。结果与对照组相比,电击伤、烧伤及擦伤组的表皮细胞均呈现出极化现象,以电击伤、烧伤组更为明显。通过主成分和偏最小二乘法分析可区分不同类型损伤,线性判别、支持向量机模型均能够有效诊断不同损伤。2 923、2 854、1 623、1 535 cm-1吸收峰在不同损伤组显示出明显的差异,电击伤的2 923 cm-1吸收峰峰强最高。结论傅里叶变换显微红外光谱结合机器学习算法为诊断皮肤电击伤、鉴定电击死提供了新技术。     

混合斑中无精子精斑DNA检验的研究

在日常性侵犯案件的DNA 检验中,经常遇到无精子精斑的混合斑,按照常规的二步消化分离法提取DNA进行STR检验则难以成功,对于此类案件常常不予检验,不能充分发挥DNA在案件中的证据作用.籍针对此类案件以Y-Plex6试剂盒对无精子精斑及其混合斑进行了检验,取得成功,现报道如下:     

家兔皮肤低电压电损伤组织病理学研究

目的研究不同数值低电压对家兔皮肤电损伤的组织病理学变化,为皮肤电损伤的法医学鉴定提供一定依据。方法选取家兔35只,随机分为36V、110V、220V生前和死后电击组各3组及正常对照组,共7组,每组5只。应用自制电击装置对家兔进行生前不同数值电压电击和死后不同时间电击,然后对电击处皮肤取材,常规石蜡包埋及HE染色制片并进行组织病理学观察研究。结果 36V生前和死后电击皮肤组织学未见改变;110V、220V生前和死后不同时间予以电击均出现电流斑改变;220V和110V生前与死后电流斑形态无差异;220V较110V电击皮肤电流斑明显。结论电流斑与电压的数值大小存在相关性,电压越高电流斑越明显,36V交流电不能形成电流斑;相同数值电压下电击,生前和死后组电流斑无明显形态学差异,电流斑在36V、110V、220V电压时不能用于区分电击损伤是否为生前或死后所致。     

电击死亡心肌收缩带的研究(附10例)

<正> 目前在电击死法医学鉴定中,主要是依据皮肤的电流斑,但在实际案例中常遇到皮肤无电流斑或电流斑不显著,给鉴定带来困难。因此必须研究电击对其他脏器损伤的证据。本文对电击死亡心肌收缩带在法医学鉴定中的意义进行了研究。     

37例电击死的法医学分析

随着电器在日常生活中的广泛使用，触电事故也逐渐增多。法医学对电击死鉴定的关键在于寻找皮肤电流损伤斑迹，但由于触电环境、电流强度、电压高低的不同，所造成的损伤形态特征或电流斑也各有不同。本文通过对37例电击死亡案件的鉴定分析，对鉴定中一些问题进行探讨。     

电击伤与电击死的法医学研究进展

电击伤和电击死是法医实践工作中常遇到的案例,尽管有许多学者从电击伤(死)后各个组织器官的形态学以及分子水平的变化进行了大量的研究,但实际检案中,法医工作者对其诊断(主要是对无电流斑的死因推断)仍没有统一的标准和直接客观的特异性指标,且对电击工具的推断、生前电击和死后电击的鉴别以及电击死后死亡时间的判断都有一定的困难,故其一直是法医学研究的热点。本文针对以上问题对电击伤(死)的法医学研究进展做一综述,为对其进一步研究提供一些思路。     

远离电击部位电流通路上骨骼肌的病理学研究

研究电损伤时骨骼肌中肌红蛋白(Mb)和纤维连接蛋白(Fn)的异常分布情况。采用大鼠模型和人体电击死标本,对电流通路上骨骼肌组织进行肌红蛋白、纤维连接蛋白免疫组化(LSAB)检测。结果显示:电流通路上肌细胞呈现深浅不同竹节样改变,免疫组化法见Mb脱失,Fn呈阳性,呈蟒蛇状纹理。电流通路上骨骼肌竹节样和蟒蛇纹理改变对无典型电流斑法医学鉴定有实用价值。     

电击伤活体鉴定1例

电击伤的活体鉴定在法医学实践中并不多见,也很少有此类报道,本文试图通过一例典型案例的分析,来共同探讨电击伤的活体鉴定问题。1案例某男,18岁。某年6月4日,应邀到某汽车修理厂检修汽车时电击致伤,伤后即被送到某县人民医院、某大学附属医院等多家医院住院治疗,伤者目前呈植物人状态。据家属介绍,现场有工业电路(380V)及汽车电路(24V)两种电路,由于汽车修理厂否认电击事实,声称张某目前情况为自身疾病所致,为查明致伤原因,进行法医学鉴定。据伤后某县人民医院住院病历记载:6月4日17:30时许,张某检修汽车电路过程中突然摔倒,意识丧失,急呼…     

Homicidal manual strangulation and multiple stun-gun injuries.

Stun guns are electric shock devices that are used by a number of law enforcement agencies to subdue violent offenders, but sometimes are discharged into human bodies as offensive weapons. We autopsied a 22-year-old woman who was strangled and had many stun-gun injuries on her head, chest, abdomen, arms, and legs. The stun-gun injuries consisted of many pairs of round erythemas with or without central paleness, some of which were accompanied by circumferential abrasions. To determine whether the electric shocks were administered before or after her death, we studied stun-gun injuries on pigs before and after death and found that the shocks after death did not mark the animal skin. Based on this experiment, all of the stun-gun injuries on the victim's body were concluded to have been inflicted before her death.     

电流斑的光镜和扫描电镜观察以及能谱测定

为了找出电流斑在扫描电镜下的特征性改变,作者用扫描电镜和能谱测定,配合光镜观察,对电击死者的22个皮肤电流斑和尸体上造成的18个皮肤电流斑和金属灼伤,进行了对比观察。结果表明,光镜下电流斑的形态改变与过去学者所述基本一致。非典型的电流斑难与热灼伤相鉴别。扫描电镜下电流斑的形态特征为:(1)损伤底部和壁上可见散在的小孔穴,直径为30～100μm,深浅不一,边缘不规则;(2)损伤组织表面大量细胞碎屑和颗粒;(3)组织和脱落细胞表面有裂纹;(4)损伤区内有散在的异物颗粒沉积,其形态为球形、方形或不规则形,电子密度较大。作者认为这些改变是电流作用造成,热灼伤不具备这些改变,故在扫描电镜下极易区别电流斑和热灼伤。所有电流斑均可测出与导体化学组成相同的金属元素。作者提出,扫描电镜下的上述形态改变和能谱测定结果可以作为诊断电流斑的依据。     

Metallization at the Exit Wound—An Unusual Finding in Fatal Electrocution

Electrocution injuries represent a severe occupational hazard. Those at work usually ignore the importance of safety training and safe practices while the electric source is nearby the work area. Death due to electrocution can occur with or without any electric mark on the body. Limbs are the commoner site for electric entry and exit wounds. Various uncommon sites for electric exit wounds have also been reported in the literature. We report a rare case of fatal electrocution, where a 28-year-old male carpenter sustained electric injuries at the worksite. Multiple exit wounds were present over the back of the chest, an uncommon site for the exit wounds, and notably, both entry and exit wounds showed evidence of metallization. The present case emphasizes on the significance of death scene investigations in the reconstruction of events and need for complete autopsy supplemented with chemical and histopathological examination of the electric wounds.     

Case reports of suicide with an electric drill

In this report, three cases of suicide by an electric power drill are described. In the first case, a man aged 51 was found with four penetrating wounds of the head and chest. The second case involves a 56-year-old man who suffered a penetrating craniocerebral injury and the third case involves a 53-year-old man who suffered one head injury and two chest injuries. In the first two cases, the victims were found dead. In the third case, the victim survived his injuries for 28 hours. The case histories and the post-mortem examinations revealed no evidence of homicide.     

Dermal surface in electric and thermal injuries. Observations by scanning electron microscopy

The dermal surface (after enzymatic digestion of the dermo-epidermal junction) in electric and heat lesions is described. There do not appear to be elements that help in forming a precise differential diagnosis. It is possible, however, to differentiate these lesions from all traumatic cutaneous injuries and some limited nontraumatic lesions (e.g., verrucae). Remarkably good preservation of the dermal surface even in an advanced state of decomposition does suggest the possibility of certain diagnosis of electric and heat lesions even when postmortem phenomena have greatly damaged or even totally removed the epithelial part of the skin.     

Bite mark or bottle top?

An alleged assault was reported by a 42-year-old female, with initial medical examination revealing an apparent bite mark on the right buttock. Odontological examination, including visual assessment, full history and photographs showed that the injury did not meet the class characteristics of a human bite. Subsequent digital overlay production showed that the injury pattern was consistent with a corrugated bottle top. This case highlights the need for careful assessment of injuries alleged to be caused by human teeth.     

The ultrastructure of the electric burn in man: a transmission electron microscopy-scanning electron microscopy study

The authors describe the ultrastructural aspects of the electric burn observed with the transmission electron microscope (TEM) and the scanning electron microscope (SEM). With the TEM the most apparent feature is the homogenization and arrangement of the filamentous cytoplasmic material in elongated and parallel bundles together with elongation of the nuclei and junctional structures. SEM studies present a three-dimensional vision of the filamentous material that confirms and clarifies the cellular deformation as a whole. An hypothesis is advanced suggesting that the phenomenon is due to the effects produced by the extremely rapid dehydration of the tissue or that the electric current and Joule effect can act upon the filaments and contractile proteins, causing the cell deformation.     

水、油污中无电流斑电击死大鼠皮肤和心肌的病变

目的探讨水中、油污中无电流斑电击死法医学鉴定的病理形态学依据。方法 SD大鼠28只,分为水中、油污中无电流斑电击死各1组,典型电流斑组、正常对照组、死后电击组、死后水中、油污中电击各1组共7组。采用肉眼、光镜及投射电镜观察水中、油污中无电流斑电击死大鼠皮肤和心肌组织病理学改变,并与其它各组进行比较。结果采用肉眼观察,生前水中、油污中无电流斑电击死大鼠皮肤未见明显电流斑。普通光镜观察,可见电击中心部位表皮变性坏死、脱落,表皮细胞变薄、致密,表皮细胞或/和毛囊、汗腺、皮脂腺发生极性化改变。电镜观察,透明层和角质层分离脱落,基底细胞肿胀、细胞器减少、核固缩,汗腺导管上皮肿胀,棘细胞中粗面内质网扩张融合成泡状,线粒体肿胀空泡化;但光镜与电镜的变化与生前电击死比较不明显、典型。而死后电击组皮肤则无明显病理学改变。实验各组大鼠心肌的改变与皮肤改变类同。结论采用光镜和投透射电镜观察在潮湿环境中电击死的组织病理学改变,可为无电流斑电击死提供依据。