扫描电子显微镜下生前和死后枪弹创的对比观察

本文用扫描电镜,对11例生前枪弹创和12例死后不同时间形成的枪弹创作对比观察。结果发现,生前枪弹创有大量红细胞和血小板凝块,纤维蛋白网形成,死后10min内的枪弹创亦有少许散在红细胞和纤维蛋白形成,很少见纤维蛋白网。死后25min的标本仍可见稀疏的红细胞,但无纤维蛋白形成。作者认为在扫描电镜下诊断生前枪弹创,需全面观察,综合分析。     

大鼠皮肤损伤纤维蛋白形成能力荧光法定量研究

本文报告采用荧光分光光度法检测损伤皮肤纤维蛋白形成能力,以探讨生前伤与死后伤的区别及不同存活时间的生前损伤之间的关系。实验结果证明,生前1min至3h的损伤皮肤纤维蛋白形成能力逐渐升高,生前30min损伤与死后伤的形成能力相比有显著差异,形成能力的检出率与死后放置时间长短和温度有关,而与该部位有无尸斑无关。     

家兔死后体表锐器伤出血现象的研究

目的对家兔死后体表锐器损伤出血现象进行研究,以期能够贴近实际办案需要,找到一个更为实用的鉴别生前锐器伤和死后锐器伤的方法。方法家兔脱毛,制作锐器损伤模型,采用大体观察结合HE染色镜下组织病理学观察。结果死后锐器损伤出血量均较少,随着时间延长出血量减少,出血速度慢。死后30min的锐器损伤在形成过程与生前损伤有所区别,但在死后12h肉眼观察结果与生前损伤难以区别。死后1h以上的锐器损伤与生前损伤不同之处在于创缘不会被血染。结论位于尸体低下位置的死后30min内的锐器创与生前锐器创的区别是出血量相对较少。死后60min-90min的锐器伤出血量少,创缘皮肤不被血染,肌肉的出血较局限,与生前损伤相鉴别较容易。     

死后肌肉切创创壁纤维蛋白的扫描电镜观察

用扫描电镜观察大鼠肌肉组织切创创壁纤维蛋白网的形成和形态,发现生前和死后8小时内的切创壁,均有纤维蛋白网形成,两者形态无显著差异。死后16小时,切创创壁无纤维蛋白网形成。     

用RT-PCR法区别生前与死后伤

12只SD大鼠随机分为生前伤、死后伤、麻醉伤和正常对照四组，损伤时间为15min，取创缘皮肤为检材；IL－6引物为寡聚核着酸引物（27hP），内对照引物为Tx基因（20hP），用TRIZOLTMTotalRNA提取试剂盒抽据总RNA，AMV逆转录酶使mRNA逆转录成cDNA，PCR扩增得出：在生前伤、麻醉伤以及正常皮肤中均能扩增出IL－6cDNA片段（590hp）和内对照Tx基因片段（188b），在死后伤组只能扩增出Tx基因片段；图像分析凝胶灰度扫描；生前损伤组与麻醉组无显著性差异，而二者与正常皮肤组有统计学差异。藉此，运用RT－PCR法可以准确区别大鼠实验性损伤的生前伤与死后伤。     

纤维蛋白及其法医学意义

纤维蛋白及其法医学意义刘敏，廖志钢，吴家损伤时间的推断是法医学领域中机械性损伤鉴定的重要任务之一，要完成这一任务，首先应明确损伤是生前形成或是死后所致；其次，若是生前伤，应估计受伤到死亡时经过的时间，即伤后存活时间。但损伤时间的推断至今仍有许多问题有...     

水中切创创壁纤维蛋白的扫描电子显微镜观察

水中尸体损伤鉴定是法医损伤鉴定中的一个难题。水中尸体上的损伤由于受到水的浸泡和腐败作用,致使创壁受到影响,常规组织学检查和一些生化、生物测定所获得的结果也因此在很大程度上失去了可信性。七十年代以来,国外有学者报告了应用 SEM观察生前、死后皮肤切创创壁纤维蛋白的情况,借以推断生前伤和死后伤。     

纤维联接蛋白的析出与大鼠皮肤早期损伤的时间关系

采用免疫组化(PAP)方法,检测大鼠皮肤损伤区的FN,发现在生前创伤后15min,创壁FN即呈明确阳性;随着伤后经历时间的延长,创壁FN逐渐增多,并滑创壁呈条带状沉积;而在死后5min的创伤,创壁FN则呈阴性。本文为区别生前与死后皮肤创伤提出了一种新的方法。     

细胞因子(IL-6、TNF-α)在损伤时间中原位杂交法研究

采用原位杂交法，研究大鼠切削皮肤中细胞团子IL－6、TNF－αmRNA表达量，旨在探讨IL－6、TNF－α推断法医损伤时间的应用价值以及其在损伤生活反应中的分子机制。研究结果表明，根据大鼠损伤皮肤中TNF－αmRNA表达量能够区别生前伤与死后伤，并可以利用TNF－αmRNA表达量改变准确区别60min内和60min后损伤时间，但IL－6mRNA表达量在研究组内均未见阳性反应，不能推断损伤时间。     

大鼠索沟生活反应的免疫组化研究

在４０只Ｗｉｓｔａｔ大鼠颈部制成５分钟至１小时生前索沟损伤模型、应用免疫组化技术（ＳＡＢＣ），观察不同损伤时间索沟常规石蜡切片上纤维连结蛋白（Ｆｎ）和纤维蛋白原（Ｆｂ）的阳性着色和分布情况。结果发现，生前索沟损伤５分钟即能在索沟部真皮组织内发现Ｆｎ和Ｆｂ阳性反应，随着损伤时间的延长，阳性反应加深。Ｆｎ和Ｆｂ最强的着色是带状显于索沟表面表皮剥脱处，除个别死后索沟真皮内有Ｆｂ的弱阳性着色外所有对照组均未见阳性反应。结果表明Ｆｎ和Ｆｂ可以作为生前和死后索沟的鉴别指标。     

对纤维蛋白诊断生前伤的评价——45例枪弹创组织的MSB染色和扫描电镜对比观察

生活反应是诊断生前伤的主要根据.近二十年来,法医病理学在研究生前伤和死后伤的诊断中,采用了多种新兴技术,如扫描电镜技术、酶组织化学技术、酶标技术、电泳技术等,促使生前伤的诊断水平有明显提高.伤后存活1小时死亡者,大部分皆可获得明确诊断;立即死亡或在濒死期形成的损伤,由于生活反应甚微,或受腐败等     

扫描电镜下缢沟的形态特征

作者用光镜和扫描电镜对縊沟进行对比观察,得出如下结论:(1)扫描电镜下縊沟组织的改变具有较恒定的特征,出血及纤维蛋白检出率远较光镜为高;(2)在光镜下生活反应不明显的生前缢沟,在扫描电镜下其表面及断面均可见红细胞及纤维蛋白形成,并包裹红细胞。縊沟部位胶原纤维之间可见散在大小不等的圆球形脂肪样小滴。缢沟部位肥大细胞的形态改变,有助于生前与死后缢沟的鉴别诊断。     

损伤皮肤酯酶显微定位、定量与损伤时间推断

作者用显微分光光度计扫描法,对32只 Hartly 豚鼠的实验性损伤以及8例人体损伤的皮肤组织中的酯酶,进行定位、定量研究。发现生前损伤后,创壁0.4mm 以内真皮胶原纤维等间质即刻出现酯酶着色,存活时间越长,着色就越深、范围越大。生前各时间组互相间有显著差异。所有的生前损伤组创缘酯酶含量及平均单位面积酶含量与正常皮肤及死后损伤组差别均极显著。人体损伤皮肤组织酯酶定位及含量变化与豚鼠所见一致。因此,作者认为损伤皮肤酯酶定位定量分析以推断损伤后存活时间,已可应用于法医实际案例鉴定中。作者还根据对抑制剂的反应认为创缘真皮胶原纤维上所显示的酯酶为 B-酯酶。     

Localization and quantification of the nonspecific esterase in injured skin for timing of wounds.

Histochemical quantification of the nonspecific esterase (NSE) in injured skin was performed using histochemical demonstration of the enzyme and a microspectrophotometric scanning technique on specimens taken from 32 Hartley guinea-pigs and 8 cases of human skin wounds. In all antemortem incisions and lacerations, including those made at the agonal stage, NSE activity could be observed in the dermal tissue of the wound edge. The enzyme activity increases with the antemortem duration of the injuries. Both total content and mean concentration of NSE in the wound edge between antemortem and postmortem wound groups differ significantly (less than 0.01). Multiple range test shows that significant differences (P less than 0.05 or P less than 0.01) of total content of NSE in the wound edge also exist in 0-5 min, 15-30 min, 1-h, 2-h and 4-h antemortem incised wound groups and in 0-min, 5-min, 15-30 min, 1-h and 4-h antemortem laceration groups. The positive NSE reactions in 8 cases of human skin wounds were similar. The study indicates that histochemical quantification of NSE in injured skin is very useful in timing wounds and is exactly applicable in medicolegal practice. According to the different influences of inhibitors on enzymes, it was inferred that the enzyme activity in wound edges was due to B-esterase.     

Determined to Die! Ability to Act Following Multiple Self‐inflicted Gunshot Wounds to the Head. The Cook County Office of Medical Examiner Experience (2005–2012) and Review of Literature

Cases of multiple (considered 2+) self‐inflicted gunshot wounds are a rarity and require careful examination of the scene of occurrence; thorough consideration of the decedent's psychiatric, medical, and social histories; and accurate postmortem documentation of the gunshot wounds. We present a series of four cases of multiple self‐inflicted gunshot wounds to the head from the Cook County Medical Examiner's Office between 2005 and 2012 including the first case report of suicide involving eight gunshot wounds to the head. In addition, a review of the literature concerning multiple self‐inflicted gunshot wounds to the head is performed. The majority of reported cases document two gunshot entrance wound defects. Temporal regions are the most common affected regions (especially the right and left temples). Determining the capability to act following a gunshot wound to the head is necessary in crime scene reconstruction and in differentiation between homicide and suicide.     

Study of elastic fiber changes of human skin in distinction between antemortem and postmortem wounds

Elastic fiber changes of volunteers' antemortem and postmortem skin wounds of various time were observed in order to find possible differences between them. These sections of the wounds were stained by Hart's modification of Weigert's elastic tissue stain.. However, this study showed that there were no differences in the nature and distribution of the elastic fibers in the dermis of volunteers' antemortem and postmortem human skin wounds. Therefore, this suggests that the appearances of the elastic fibers in the dermis should not be as a means of differentiating antemortem skin wounds from postmortem wounds in forensic identification.     

Localization and quantification of histamine in injured skin as parameters for the timing of wounds.

Localization and estimation of the histamine (HA) content in skin wound edges in 86 Sprague-Dawley rats and three cases of human injuries were carried out by a microfluorimetric method specific for this amine which forms a complex with o-phthalaldehyde (OPT). Distribution and density of the mast cells in the same areas were observed at the same time by toluidine blue stain. In all skin specimens with antemortem wounds, both the epidermis and upper dermis exhibit extracellular yellowish fluorescence of the HA-OPT complex. The fluorescent zone spreads in the wound edges with the lapse of time in vital injuries. The HA content increases gradually up to 30 min and then the yellow histamine fluorescence in areas 0-200 microns from the wound edge decreases. None of these features can be observed in normal skin and postmortem-injured skin. Mast cell degranulation can be demonstrated in all antemortem-injured skin. No statistical relationship exists between the number of mast cells and the HA-OPT fluorescence in either ante- or postmortem-injured groups. This study indicates that skin HA microfluorimetry by the OPT method is of practical value for distinguishing ante- from the postmortem wounds and for timing antemortem wounds.