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Postmortem investigation is increasingly supported by computed tomography (CT) and magnetic resonance imaging, in which postmortem minimal invasive angiography has become important. The newly introduced approach using an aqueous contrast agent solution provided excellent vessel visualization but was suspected to possibly cause tissue edema artifacts in histological investigations. The aim of this study was to investigate on a porcine heart model whether it is possible to influence the contrast agent distribution within the soft tissue by changing its viscosity by dissolving the contrast agent in polyethylene glycol (PEG) as a matrix medium. High-resolution CT scans after injection showed that viscosities above c. 15 mPa s (65% PEG) prevented a contrast agent distribution within the capillary bed of the left ventricular myocardium. Thereby, the precondition of edema artifacts could be reduced. Its minimal invasive application on human corpses needs to be further adapted as the flow resistance is expected to differ between different tissues.  相似文献   
175.
The Suicide Risk Assessment Scale (SRAS; nine items) is useful in correctional settings but needed further validation. First, 44 inmates originally screened as suicidal with the SRAS were evaluated by institutional psychologists according to five criteria: suicidal urgency, risk, appropriateness of referral, need for short- or long-term watch. On the whole, the SRAS was judged to be as effective as a more elaborate test. Second, 242 suicidal and non-suicidal inmates were tested with the SRAS. Their results correlated better with suicidal risk (.71) than with urgency (.50). Receiver operating characteristic (ROC) analysis even showed that the SRAS performed better than a more elaborate test in predicting risk.  相似文献   
176.
The occurrence of two null alleles for the same individual was suspected because of the discrepancy at two loci (vWA and THO1) between genotypes characterized by the mean of two different commercial kits. Reanalysis of the samples indicated there was no null allele, and that this abnormality was indeed related to an automatic laser power shutdown. The laser power supply was set to a value (6.4V) too close to the automatic shutdown threshold (6.0V). The alleles were undetected because of the absence of emission at the time of migration of the two alleles through the detection device. However, since no alarm is triggered in such an event, the users should monitor their laser power supply values.  相似文献   
177.
A collaborative study was conducted in France in order to determine the prevalence of cannabinoids, opiates, cocaine metabolites and amphetamines in blood samples from drivers killed in road accidents in 2003 and 2004 and to compare these values with those of a previous study performed during the period 2000-2001 involving 900 drivers. Blood samples were provided from 2003 under 30-year-old drivers, killed in a traffic accident. Drugs of abuse were determined by gas chromatography-mass spectrometry using the same analytical procedures in all the 12 laboratories. The most frequently observed compounds were by far cannabinoids, that tested positive in 39.6% of the total number of samples. Delta9 tetrahydrocannabinol (THC), the most active of the principle constituents in marijuana (cannabis sativa), was detected in the blood of 28.9% drivers and was the single drug of abuse in 80.2% of the positive cases. It was associated with amphetamines in 7.4% and with opiates and cocaine in 1.9 and 4.8%, respectively. Amphetamines were present in 3.1% of the total number of samples, cocaine metabolites in 3.0% and opiates in 3.5%. When comparing these results with those of a previous study performed 3 years before, a significant increase is observed for THC (28.9% versus 16.9%), cocaine metabolites (3.0% versus 0.2%) and amphetamines (3.1% versus 1.4%). This study demonstrates the critical necessity of implementing in France as soon as possible systematical roadside testing for drugs of abuse.  相似文献   
178.
A 30-year-old man was admitted with chest trauma after a road traffic accident. The patient was paraplegic and suffered from transient monoparesia of the left arm. The chest X-ray revealed a severe right tension pneumothorax and thoracic spine fractures. Emergency right thoracic drainage was carried out followed by angiography. Unfortunately the patient died and an autopsy was not permitted. Consequently post-mortem multi-slice computed tomography (MSCT) was performed, revealing presence of air inside the right cerebral arteries, bilateral pneumothorax accompanied by a severe right tension pneumothorax, bilateral haematic pleural effusion, pneumomediastinum and bilateral lung contusions. Air was also observed within the right coronary artery, ascending aorta and right ventricle. Thoracic and cervical spinal epidural emphysema were diagnosed. Venous air embolism followed by arterial air embolism producing paradoxical embolism was diagnosed. To the best of our knowledge, this is the first case illustrating by post-mortem MSCT such simultaneous complications after chest trauma as spinal epidural emphysema and cerebral and coronary air embolism.  相似文献   
179.
A prospective study of 161 victims of falls from height is reported. The aim was to determine the interest of systematic qualitative and quantitative toxicological analysis in such fatalities. The primary cause of death was suicide (84.5%), followed by accidents (7%) and homicide (1%). In the remaining 7.5%, cause of death was undetermined. In the suicides, there was evidence of psychotropic medicines in 57% of the observations, with a much higher proportion of benzodiazepines and antidepressants in women than in men. Quantitative toxicologic analysis showed overdosing on medication in 16 suicide victims, with toxic levels in 11 of these. Systematic qualitative and quantitative toxicologic analysis made a significant contribution to the diagnosis of suicide by revealing either an unknown psychiatric treatment or a toxic level.  相似文献   
180.
Allele frequencies for 18 STR autosomal loci (D3S1358, VWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317, D7S820, D16S539, TH01, TPOX, CSF1PO, Penta D, Penta E, D19S433, D2S1338 and SE33) were obtained from a sample of 191-500 unrelated individuals from Costa Rica, Central America.  相似文献   
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