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111.
A Computational Framework for Age‐at‐Death Estimation from the Skeleton: Surface and Outline Analysis of 3D Laser Scans of the Adult Pubic Symphysis 下载免费PDF全文
Bridget F. B. Algee‐Hewitt Ph.D. Jieun Kim Ph.D. Dennis E. Slice Ph.D. 《Journal of forensic sciences》2017,62(6):1434-1444
In forensic anthropology, age‐at‐death estimation typically requires the macroscopic assessment of the skeletal indicator and its association with a phase or score. High subjectivity and error are the recognized disadvantages of this approach, creating a need for alternative tools that enable the objective and mathematically robust assessment of true chronological age. We describe, here, three fully computational, quantitative shape analysis methods and a combinatory approach that make use of three‐dimensional laser scans of the pubic symphysis. We report a novel age‐related shape measure, focusing on the changes observed in the ventral margin curvature, and refine two former methods, whose measures capture the flatness of the symphyseal surface. We show how we can decrease age‐estimation error and improve prior results by combining these outline and surface measures in two multivariate regression models. The presented models produce objective age‐estimates that are comparable to current practices with root‐mean‐square‐errors between 13.7 and 16.5 years. 相似文献
112.
目的观察双侧阴茎背神经、海绵体神经损伤.以及联合神经损伤后阴茎海绵体组织细胞凋亡表达。方法(1)将78只SD大鼠随机分为术后1、2、4、8、16和32d组,每组分别分为海绵体神经离断组、阴茎背神经离断组、阴茎背神经和海绵体神经联合离断组、手术对照组和非手术对照组。通过DNA梯带法(DNAladder)进行定性、TUNEL法进行凋亡细胞检测;用actin-α标记平滑肌细胞。用CD31标记内皮细胞,进行凋亡细胞定位。结果双侧海绵体神经损伤及联合损伤组分别与阴茎背神经损伤组、手术对照组和非手术对照组之间的凋亡率均有显著差异(P〈0.0046),但两组之间的差异无显著性(P〉0.0046),双侧阴茎背神经损伤组与手术对照组之间细胞凋亡率差异无显著性(P〉0.0046)。海绵体平滑肌细胞凋亡平均数与内皮细胞的凋亡平均数差异具有显著性(P〈0.05)。结论海绵体神经损伤可引起阴茎海绵体平滑肌的凋亡;阴茎背神经损伤对阴茎组织细胞凋亡无明显影响;联合损伤对海绵体平滑肌细胞凋亡的影响同单纯海绵体神经损伤。 相似文献
113.
脑损伤后普遍存在的炎性反应激活补体并通过多种途径导致和加重继发性脑损伤。膜攻击复合物具有直接破坏血脑屏障、促使红细胞溶解、促进释放细胞因子、氧自由基和金属基质蛋白、加剧炎症反应的生物特性,从而加重继发性脑损伤。本文对膜攻击复合物造成继发性脑损伤的研究进行综述,希望能对相关研究和法医学鉴定提供参考。 相似文献
114.
Cross R 《Journal of forensic sciences》2006,51(1):93-99
Two case studies are presented involving fatal falls of adult females from a height. One involved a launch at low speed from a balcony, and one involved a launch at high speed from the top of a cliff. Crime scene evidence obtained on the balcony itself provided a strong indication of homicide, but subsequent investigation showed that the fall was accidental. No crime scene evidence was obtained for the cliff fall since the fall initially appeared to be just another suicide from a popular suicide spot. Subsequent investigations indicated homicide based on measurements of cliff height, horizontal distance to the impact, and available runup distance, plus measurements of possible run, jump, and throw speeds. It was found that a female weighing 61 kg (134 lb) can be thrown at speeds up to 4.85 m/s by a strong male, more than enough to account for the estimated launch speed (4.5 m/s). Given the available 4.0 m runup distance, it was found that women of better than average rather than elite athletic ability can dive at speeds of about 3.5 m/s or jump feet first at speeds of about 4.0 m/s, both being less than the estimated launch speed. The decedent had no athletic ability and landed head first after falling through a height of 29 m. 相似文献
115.
目的调查DYS391等24个Y-STR基因座在南京汉族人群的遗传多态性,考察其在法医学中的应用价值。方法应用AGCU Y-PLUS(24)PCR试剂盒对南京580名汉族无关男性个体进行Y-STR基因座扩增检测分型,用软件计算24个基因座的基因频率等群体遗传学参数,并与湖北、辽宁、广东、北京、成都汉族人群数据进行比较。结果南京580名汉族无关男性个体在24个Y-STR基因座共发现580种单倍型,各基因座的基因多样性(GD)为0.294 6~0.939 8,单倍型多样性(HD)为0.983 7。六地人群GD值的差异有统计学意义。结论 DYS391等24个Y-STR基因座在南京地区有法医学价值,可用于案件检验及家系排查。 相似文献
116.
甲基苯丙胺(MA)是近年来在我国公共场所流行滥用的成瘾性药物,俗称冰毒。目前实验研究发现,MA对人体多个系统都具有毒性作用,其中对心血管系统的毒性损害作用较为显著。临床表现上,MA中毒主要导致了以心率和血压改变为特异性表现的一系列症状,以及继发的心脏结构改变所导致的心脏损害;病理学上,MA中毒导致了心肌坏死、心肌间质炎细胞增多、心肌纤维化、心肌梗死等。法医学研究中,发现了MA急性中毒导致死亡的主要原因是MA引起的心律失常和室颤,慢性中毒的死因较多,以MA慢性中毒导致高血压、心肌病、心肌梗死等为主。MA中毒的心肌毒性的分子机制表现为心肌内多种蛋白质表达的改变。目前MA心肌毒性的机制研究较多,但仍未完全查明。本文通过对近年来MA心肌毒性研究现状进行综述,为后续研究提供参考。 相似文献
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119.
An Analysis of the Characteristics of Thoracic and Abdominal Injuries Due to Gunshot Homicides in Israel 下载免费PDF全文
Nicholas R. Maiden Ph.D. Jehuda Hiss M.D. Hadas Gips M.D. Gil Hocherman M.Sc. Nadav Levin M.Sc. Olga Kosachevsky M.Sc. Asya Vinokurov M.Sc. Avraham Zelkowicz M.Pharm. Roger W. Byard M.D. 《Journal of forensic sciences》2016,61(1):87-92
De‐identified wound data from 197 homicidal gunshot postmortems were obtained between 2000 and 2008. Forensic ballistics data were only available for cases between 2004 and 2008. Males represent 91% of gunshot victims and were struck in the thorax/abdomen with an average of 2.3 bullets. The type of firearms involved were semi‐automatic pistols in the predominant caliber 9‐mm Luger and assault rifles in caliber 5.56 × 45 mm and caliber 7.62 × 39 mm Soviet, using full metal jacket bullets. The majority of shootings occurred at ranges of 1 m or greater. The most common bullet path was front to back in 66% of cases. Entry wounds occurred more often on the left side of the thorax, abdomen, and back. The most common critical organs/tissues to sustain bullet trauma in descending order were as follows: heart, lungs, liver, aorta, spleen, kidneys, and vena cava. Ribs were struck by most bullets that entered the thorax. 相似文献
120.
A finding in the autopsy of John Paul Jones, the American Revolutionary War naval hero, may explain his terminal illness. During his last 2 years, he had a persistent productive cough and dyspnea. Ten days before death, he developed rapidly progressive dependent edema and ascites. He died in France in 1792. His body, preserved in alcohol in a lead coffin, was, in 1905, removed to the United States. Glomerulonephritis was noted on an autopsy, performed in France, but there was no comment then or since about ventricular wall thickness being the same in both ventricles at 5–6 mm. Hypertrophy and dilatation with biventricular failure followed by tissue shrinkage during 113 years in alcohol could have resulted in these ventricular wall findings. Systemic hypertension and left ventricular failure are consistent with his respiratory symptoms complicated perhaps by pulmonary emboli, right ventricular failure with tricuspid regurgitation, peripheral congestion, and jaundice. 相似文献