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991.
This case concerns an unusual suicidal plastic bag suffocation. An elderly white man was found dead and partially disrobed in his apartment lying supine on a sofa with a plastic bag closed by a rope over the head and the upper and lower extremities tightly tied with two other ropes, the end of both arranged into slipknots (self-rescue mechanism). Police investigations found no pornography in the apartment, and circumstantial data alleged no psychiatric disorders or suicidal intentions. The autopsy excluded signs of struggle and sexual intercourse as well as any type of injury or physical illness. Chemical analyses on the peripheral blood excluded acute drugs and/or alcohol intoxication. A differential diagnosis of the manner of death was performed, including scenarios of accidental autoerotic asphyxiation, homicide during either sexual activity or ritualistic, elderly suicide. The collected data most strongly supported the hypothesis of a suicidal asphyxiation simulating homicide to devolve a life insurance to the victim's sons because of economic difficulties.  相似文献   
992.
Abstract: This study assesses the predictive value of anterior sacral curvature for sex estimation from skeletonized remains. Sacra from a sample of 125 American adults of known age and sex were examined. Nine measurements describing anterior sacral curvature were used in the analysis. Statistical treatment of the data included univariate statistics and discriminant function analysis for sex classification. A bootstrap validation method was employed to assess the classification error rates. Sacral curvature was significantly greater in men than in women at the level of the S2–S3 and S3–S4 articulations (p < 0.05). Correct classification estimates for the discriminant function range from 66–72%. Although sexually dimorphic, metric observations of sacral curvature are not as reliable at predicting sex as other skeletal elements. Anterior sacral curvature should only be used for sex estimation in the absence of other, more reliable, indicators.  相似文献   
993.
Abstract: Pyrodex ® and Triple Seven ® are black powder substitutes that often find use as fillers in improvised explosive devices, such as pipe bombs. These propellants have essentially the same overall appearance and oxidizers, but different fuels. For example, Pyrodex ® contains sulfur, sodium benzoate, and dicyandiamide (DCDA), whereas Triple Seven ® lacks sulfur but also contains 3‐nitrobenzoic acid. In this method, intact particles and postblast solid residues were reacted with bis(trimethylsilyl)trifluoroacetamide + 1% trimethylchlorosilane in acetonitrile for 30 min at 60°C. The resultant trimethylsilyl derivatives of the organic fuels were then analyzed by gas chromatography–mass spectrometry. Each derivative was clearly resolved from other components, and high‐quality mass spectra were obtained. In addition, characteristic fragments resulting from loss of a methyl radical from the molecular ion (m/z 163 for sulfur, m/z 171 for DCDA, m/z 179 for benzoic acid, and m/z 224 for nitrobenzoic acid) were able to be monitored.  相似文献   
994.
Laser detection of latent fingerprints on a white paper has been performed, previously. Ultraviolet fluorescence from various kinds of printer toner and ink used for home printers were measured to study fluorescence imaging of fingerprints on a color-printed white paper. The experimental system consisted of a nanosecond pulsed tunable laser and a cooled CCD camera. Excitation wavelengths are 230 and 280 nm. Fourteen printers consisting of three color laser printers, three color inkjet printers, five monochrome laser printers, two monochrome copy machines, and a color copy machine were tested. Toner and ink of most printers exhibited fluorescence in the region from 360 to 550 nm. In most cases, clear fluorescence images were obtained by time-resolved imaging with a band-pass filter and 280-nm excitation. However for toners from laser color printers that showed strong fluorescence, better results were obtained with 230-nm excitation. Latent fingerprints on a photograph page and a black-character page of a newspaper were also imaged.  相似文献   
995.
Measurement of the amount of fat in femoral bone marrow can provide a quantitative assessment of the nutritional status of an individual animal. An analytical method is presented for quantitating the percent fat in bone marrow from three domestic species: bovine, canine, and equine. In this procedure, fat is extracted from bone marrow using pentane, and the percent fat recovered is determined gravimetrically. Based on analyses from adult animals (normal body condition scores), the average percentage of fat in the bone marrow was >80%. In cases in which animals have been diagnosed as emaciated or exhibit serous atrophy of fat (body scores of 1 or 2), the femoral bone marrow fat was less than 20%. In domestic animals, bone marrow fat analysis can be a useful, quantitative measure that, when used in conjunction with all other data available, can support a diagnosis of starvation or malnutrition.  相似文献   
996.
A well-documented case of so-called Spontaneous Human Combustion is reported. Review of the literature shows that these strange observations have been reported since the 17th century, even in famous novels. There are several main features that may lead to help the diagnosis: the vicinity of the body is intact or nearly intact, some parts of the body are turned into ashes (usually the middle third of the body), whereas other parts are intact or nearly intact, burning of the body usually occurs postmortem, the cause of death is usually natural, there is often (but not always) high concentrations of blood alcohol, there is a source of heat near the body. It is indispensable to rule out a homicide by the examination of the body in situ, the autopsy, the toxicological and histopathological samples, the arson assessment, and a thorough police inquiry.  相似文献   
997.
Abstract: Amussat’s sign is typically a transverse laceration of the intimal layer of carotid arteries described in cases of hanging. Subtotal laceration of the carotid artery is not strictly specific for hanging and can be also caused by blunt neck trauma, extreme overstretching, or whiplash‐injuries. In a prospective autopsy study of 178 cases of hanging, Amussat’s sign was found in 29 cases (a relative frequency of 16.1%). A statistically significant association between the occurrence of tears in the intimal layer of carotid arteries and the victims’ age was discovered in the cases studied (the frequency increased with age; p < 0.05). The occurrence of Amussat’s sign was independent of gender, weight, completeness of the victim’s body suspension, and position of the ligature knot on the neck. The study demonstrates the fact that the most probable cause of Amussat’s sign is a combination of direct compression of the artery by the rope and indirect stretching because of the gravitational drag produced by the weight of the body.  相似文献   
998.
甲基苯丙胺和乙醇在染毒大鼠体内联用的实验研究   总被引:1,自引:1,他引:0  
目的研究甲基苯丙胺(MA)和乙醇联合应用在急性、亚急性染毒大鼠体内的情况。方法以MA1.0 mg/kg剂量对慢性自由饮酒大鼠多次腹腔注射,分别建立急性、亚急性染毒大鼠模型;处死后即时检测血中乙醇浓度、体液和组织样品中MA的浓度。结果多次注入MA药后,亚急性中毒大鼠体内的MA浓度高于急性中毒大鼠;急性和亚急性联合中毒大鼠体内MA浓度均高于急性和亚急性单一药物组。结论无论是否联用乙醇,14d内增加注射次数会在大鼠体内产生不同程度的MA残留;与乙醇联用可加速MA在大鼠体内的吸收,其药物浓度的升高程度随生物样品不同存在差异。  相似文献   
999.
目的探讨兔重伤后机体内铜(Cu)含量及其代谢酶铜锌超氧化物歧化酶(Cu/Zn-SOD)、细胞色素c氧化酶(CCO)活性变化与继发性多器官衰竭(MOF)及死亡的关系。方法参照国际通用的创伤程度量化评分标准(ISS),建立致MOF的家兔重伤模型,检测伤后不同时段血清及组织Cu含量与Cu/Zn-SOD和CCO的活性,分析其变化规律与继发MOF及死亡的关系。结果①重伤组家兔(包括死亡组家兔)血清Cu含量在伤后12h显著下降,36h后逐步回复;脑、心、肺组织中Cu含量伤后下降,肝脏组织Cu含量于伤后12h显著升高,36h后回落。伤后死亡组家兔脑、心、肺、肝Cu含量均较对照组降低,其中脑、肝组织Cu含量下降显著。②重伤组家兔血清Cu/Zn-SOD活性伤后12h下降3,6h之后呈升高的趋势,肝脏组织中的Cu/Zn-SOD活性伤后持续显著升高。③重伤后家兔(包括死亡组家兔)大脑皮质、心、肝CCO活性变化不明显,但脑干组织CCO活性显著升高。伤后死亡组家兔脑、心、肺、肝等器官的大体及组织学呈MOF改变。结论严重创伤可引发兔血清和组织Cu水平及Cu/Zn-SOD、CCO活性变化,这些变化可能与继发多器官衰竭和死亡相关。  相似文献   
1000.
中暑死与冻死在法医学鉴定实际工作中并不常见,但由于其病理学表现往往不够明显,在法医实际鉴定时易被漏诊。本文作者查阅了国内外相关文献资料,并结合作者实际法医学鉴定经验将中暑死与冻死的法医学鉴定要点作出初步的总结。  相似文献   
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