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981.
982.
Qualitative and quantitative composition and time course of formation of toxic substances during burning of polymers have been studied for two polymers, P-53-P and STBO. The most toxic gaseous products of nitrogen combustion are listed: hydrogen cyanide, nitrites, acid nitriles, aldehydes, aromatic carbohydrates, alkanes, and carbon oxide. Two expert conclusions are presented, including analysis of blood and viscera from subjects who died during fire. The following toxic substances were detected: carbon oxide, hydrogen cyanide, nitrites, acrylonitrile, acetonitrile, benzene, and methane in one case and the same products except carbon oxide in the other. The author considers that the list of tested toxic substances should be extended, particularly in cases with negative results of blood testing for carbon oxide and carboxyhemoglobin.  相似文献   
983.
984.
Advances in the diagnosis of wound vitality: a review   总被引:2,自引:0,他引:2  
The diagnosis of the vital origin of wounds in many cases remains an unsolved problem for the forensic pathologist. Practical experience enables the expert to diagnose the vital or postmortem origin of wounds on the basis of macroscopic examination. In some cases, optic microscopy is used to confirm the diagnosis. In many other cases, additional more sensitive and specific markers of vitality are required. In the past 50 years, comprehensive research on this topic has resulted in a better understanding of the acute inflammatory reaction. The development and application of sensitive and specific markers through research in the areas of histochemistry, enzymology, and biochemistry has provided a partial solution to the problems involved in wound vitality diagnosis. A review of this challenging area of forensic pathology, including an explanation of these methods and markers, is presented in this paper.  相似文献   
985.
986.
A rare and potentially fatal cause of hematemesis is fistula formation between the esophagus and the vascular system. A case report of a 39-year-old woman with congenital aortic arch anomalies hospitalized for treatment of head injuries demonstrates the potential for iatrogenic esophageal trauma to initiate fistula formation between the esophagus and an anomalous arterial system. A literature review revealed 6 other cases of vascular-esophageal fistulae caused by nasogastric esophageal intubation. It is concluded that aortic arch anomalies increase the risk of esophageal injury and subsequent fistula formation from nasogastric esophageal intubation. In addition, the clinical features and pathologic findings of vascular-esophageal fistulae are reviewed.  相似文献   
987.
The diagnosis of sudden infant death syndrome (SIDS) has been an enigma to medical examiners and coroners for decades. The recent drastic decrease in the number of SIDS cases has been associated with infants sleeping supine instead of prone. The apparent relation between sleeping position and SIDS has led to the marketing of several positioning sleep aids. We report a case of the improper use of one such device which resulted in the death of an infant.  相似文献   
988.
A retrospective analysis of 68 cases of fatal childhood pedestrian accidents in South Australia that occurred over a 20-year period from January 1977 to December 1996 was undertaken. The age range was 12 months to 16 years (average, 7.6 years), with a male to female ratio of 41:27. The most common site of significant injury was the head (91.2%), followed by the abdomen (50%), chest (47.1%), and neck (38.2%). The most frequently encountered significant injury combinations involved the head, chest, and abdomen (14.7%); the head and chest (11.8%); and the head, neck, and abdomen (11.8%). Injuries were severe, consisting of extensive compound and comminuted skull fractures, neck fractures, and massive intraparenchymal brain and internal organ damage with avulsions and fragmentation. Non-life-threatening limb injuries occurred in 88% of cases. A distinct subgroup involved infants and younger children playing in driveways at home who were hit by reversing vehicles. The injuries were often of such a severe nature that death was instantaneous and with no possibility of successful medical intervention. More deaths occurred during the winter than summer months.  相似文献   
989.
The present study investigated the effect on witness confidence and accuracy of confusing questions often used by attorneys in court. Participants viewed a videotaped film and were individually questioned about the incident 1 week later. Half the participants were asked questions using six categories of confusing questions (negatives, double negatives, leading, multiple questions, complex syntax, and complex vocabulary); the remaining half were asked for the same information using simply phrased equivalents. Confusing questions reduced participant-witnesses' accuracy and suppressed confidence–accuracy relationships compared with the condition where simplified alternatives were asked. Witness performance was impaired by the fact that mock-witnesses rarely asked for a confusing question to be explained or qualified their answers. This experiment demonstrates the importance of ensuring that lawyers ask witnesses simple, clear, questions.  相似文献   
990.
Hair samples are useful as a matrix for drug testing because drugs can be detected in hair for longer periods than in blood or urine. The authors report a prospective comparison of the detection of cocaine and cocaethylene in routine postmortem biologic specimens to the detection of cocaine and cocaethylene in hair. The authors collected hair samples from various areas of the head in 53 autopsy cases, prepared them, and analyzed them by gas chromatography/mass spectrometry (GC/MS) for cocaine and cocaethylene. The authors compared the results of hair analysis with the results of toxicologic analysis performed on routine postmortem samples by enzyme multiplied immunoassay technique and GC/MS. Cocaine was found in either biologic fluids or in hair in 16 of 53 samples tested. Nine samples were positive for cocaine in both biologic fluids and hair. Five samples contained cocaine only in biologic fluids, and two contained cocaine only in hair. Cocaethylene was present in two cases. Drug screening of hair provides additional information in some autopsy cases, but the authors have not made hair analysis a routine practice. It may prove useful to save hair samples in all cases for later analysis if warranted by additional history or autopsy findings.  相似文献   
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