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141.
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143.
Following ingestion of 30 mg of presumed benztropine (Cogentin) a 39-year-old male developed nausea, vomiting and diarrhea. His admission to hospital was soon followed by collapse and death. Histological examination, however, revealed increased numbers of mitotic figures in otherwise normal epithelial cells of the esophagus and bronchioles, a feature characteristic of colchicine toxicity. Subsequent toxicological analyses confirmed the presence of colchicine in the urine, but not in the blood. A dispensing error had resulted in substitution of colchicine for Cogentin. Histological findings had, therefore, provided evidence of colchicine toxicity and had guided subsequent toxicological evaluation. In suspected cases of colchicine toxicity, histological samples should, therefore, be taken from multiple sites along the gastrointestinal and respiratory tract in addition to other organs and tissues so that diagnostic morphological changes can be looked for.  相似文献   
144.
Two cases of dangerous sleeping environments in the elderly are reported to demonstrate similarities and differences of these "sleeping accidents" to similar episodes that occur in infants and children. CASE REPORTS: An 87-year-old wheelchair-bound man with a history of dementia was found in his nursing home room hanging off the side of the bed from a vertical metal bar, and an 87-year-old woman with epilepsy, ischemic heart disease, and insulin-dependent diabetes mellitus was found in hospital wedged between an inflatable mattress and the bars of her bed. These cases demonstrate that, as in the very young, relatively poor coordination and strength in the elderly often with limited comprehension and ability to deal with dangerous environments may predispose to sleeping accidents. Significant underlying organic disease may, however, make determination of the precise lethal mechanisms difficult. Modification of beds should only be undertaken when safety issues have been carefully evaluated.  相似文献   
145.
Tracheostomy is widely used to facilitate respiration by protecting the airways. It may be performed to relieve upper airway obstruction from congenital stenoses or from acquired conditions such as foreign body impaction, swelling from neck trauma or anaphylaxis, benign or malignant tumors, and infection. Tracheostomy may also be performed in individuals with respiratory impairment who require suctioning for accumulated mucoid secretions and in those with obstructive sleep apnea. Review of autopsy files and the literature was undertaken to demonstrate the range of lethal circumstances that may involve tracheostomy. Unexpected death may result from incorrect positioning of an endotracheal tube with failure of oxygenation, tracheal perforation with pneumothorax, mucus plugging, accidental extubation, and hemorrhage from tracheovascular fistulas. Lethal tracheovascular fistulas usually involve the innominate artery and result from mural perforation by the tip of a tracheostomy tube, mural necrosis from a high-pressure cuff, prolonged intubation, radiotherapy, and low tracheal incisions. Increased movement of tubes in patients with impaired consciousness and excessive head movements may also increase the chances of hemorrhage, as may infiltrating tumors. Given the wide range of potential fatal mechanisms that may be found in such cases, careful autopsy evaluation and dissection will be required to demonstrate the exact nature and site of the lethal lesion in individuals who underwent tracheostomy and die unexpectedly.  相似文献   
146.
An 84-year-old woman is reported whose death was associated with strenuous exercise on an extremely hot day (maximum temperature=43.1 °C, 109.6 °F). At autopsy there was evidence of exposure to high environmental temperatures with early putrefactive changes and mummification. There was underlying cardiomegaly with mild pulmonary emphysema. No significant injuries were detected. Toxicology revealed therapeutic levels of oxybutynin prescribed for urinary stress incontinence. Death was considered to be heat related, exacerbated by oxybutynin therapy, exercise, and cardiomegaly. Given that it has been predicted that there may be an increase in the number of heatwaves and in their intensity and duration, it is possible that such cases may be encountered more often in future. The assessment of all deaths occurring during conditions of extreme heat will require consideration of postmortem toxicology, particularly if there are underlying conditions such as stress incontinence that may be associated with anticholinergic drug therapy.  相似文献   
147.
Pseudoxanthoma elasticum (PXE) is a generalized connective tissue disorder in which there is calcification of elastic fibers within arteries, eyes, and skin. Characteristic features include yellow-orange papular skin lesions, angioid streaks radiating out from the optic discs, and arterial calcification. The prevalence in the general population varies widely from 1/70,000 to 1/160,000. PXE has an autosomal recessive inheritance pattern and results from mutations in the ATP-binding cassette transporter C6 (ABCC6) that has been mapped to 16p13.1. Over 300 loss-of-function mutations have been identified. Individuals with PXE may come to forensic attention because of sudden death involving accelerated coronary atherosclerosis with acute myocardial ischemia, systemic hypertension, mitral valve prolapse, restrictive cardiomyopathy, gastrointestinal hemorrhage, and cerebral ischemia or hemorrhage. Because of the heritable nature of the disease, family counseling and screening are in order when previously unsuspected cases are encountered at autopsy.  相似文献   
148.
Deaths due to the ring-derivative amphetamines are not common and are usually accidental involving dehydration and hyperthermia. Suicides from 3,4-methylenedioxymethamphetamine (MDMA) and related ring-derivative amphetamines overdose are rare. A 15-year-old female who had a history of depression and previous suicide attempts was found dead with a suicide note. Toxicology demonstrated lethal serum concentrations of MDMA (9.3 mg/L), with 34 mg/kg of MDMA in the liver, 2.4 mg/L in the urine, and 530 mg/kg in the stomach. The cause of death was MDMA toxicity, the manner suicide. While MDMA may be detected in victims in other drug-related or traumatic deaths, it is only rarely used in isolation in suicide, with a predominance in the 21- to 25-year-old range. Despite the rarity of such events, the possibility of a nonaccidental manner of death should be considered when high levels of MDMA and associated amphetamines are found at autopsy.  相似文献   
149.
Inkjet ink analysis is the best way to discriminate between printed documents, or even though more difficult, to connect an inkjet printed document with a brand or model of printers. Raman spectroscopy and laser desorption mass spectrometry (LDMS) have been demonstrated as powerful tools for dyes and pigments analysis, which are ink components. The aim of this work is to evaluate the aforementioned techniques for inkjet inks analysis in terms of discriminating power, information quality, and nondestructive capability. So, we investigated 10 different inkjet ink cartridges (primary colors and black), 7 from the HP manufacturer and one each from Epson, Canon and Lexmark. This paper demonstrates the capabilities of three methods: Raman spectroscopy, LDMS and MALDI-MS. Raman spectroscopy, as it is preferable to try the nondestructive approach first, is successfully adapted to the analysis of color printed documents in most cases. For analysis of color inkjet inks by LDMS, we show that a MALDI matrix (9-aminoacridine, 9AA) is needed to desorb and to ionize dyes from most inkjet inks (except Epson inks). Therefore, a method was developed to apply the 9AA MALDI matrix directly onto the piece of paper while avoiding analyte spreading. The obtained mass spectra are very discriminating and lead to information about ink additives and paper compositions. Discrimination of black inkjet printed documents is more difficult because of the common use of carbon black as the principal pigment. We show for the first time the possibility to discriminate between two black-printed documents coming from different, as well as from the same, manufacturers. Mass spectra recorded from black inks in positive ion mode LDMS detect polyethylene glycol polymers which have characteristic mass distributions and end groups. Moreover, software has been developed for rapid and objective comparison of the low mass range of these positive mode LDMS spectra which have characteristic unknown peaks.  相似文献   
150.
Despite advances in child maltreatment research, accurate measurement of exposure remains a key issue. In this study, we evaluated a short form (CEVQ-SF) of the Childhood Experiences of Violence Questionnaire (CEVQ) in a sample of adolescents involved with child protection services in an urban city in Ontario, Canada. Focusing on the two most readily defined maltreatment types, physical and sexual abuse, we evaluated the short form's comparability with the full version of the CEVQ. Both versions had good internal consistency and moderate-to-good 2-week test-retest reliability. The criterion validity of the two CEVQ versions in comparison with the Childhood Trauma Questionnaire was satisfactory. Construct validity for both versions was demonstrated: physically and sexually abused youth had higher odds of reporting clinical traumatic symptoms compared with either type alone. The CEVQ-SF is as reliable and valid as its full version. Implications for its use in large population-based surveys are discussed.  相似文献   
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