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851.
The authors have reported a macro- and microscopic study of brain lesions in 120 victims of fatal road traffic accidents, independent of the survival time. Diffuse vascular injury (DVI) was found in 14 patients (11.7%). All patients with DVI died within 24 h after the accident. The 14 patients with DVI also showed severe (Grade 2 or 3) diffuse axonal injury (DAI). Since DVI is restricted to road traffic accidents and incompatible with life, the high frequency observed in our series could be explained by the fact that all 120 patients were victims of road traffic accidents, and 69.2% had died within 24 h after the accident. The association between DVI and severe DAI (Grades 2 and 3) suggests that both lesions depend on the same mechanism, with the degree of axonal and vascular damage being determined by the intensity of the head acceleration. Our results show a relationship between DVI and DAI that suggest there may be a spectrum or at least a continuum between these entities as distinct from DVI being a separate entity.  相似文献   
852.
Gene and genotype frequencies in relation to the low density lipoprotein receptor (LDLR), glycophorin A (GYPA), hemoglobin G gammaglobin (HBGG), D7S8, and group specific component (Gc) loci were determined in a sample of 344 unrelated individuals (250 whites and 94 mulattoes) living in the city of S?o Paulo, Brazil. DNA was extracted from 5 mL of peripheral blood obtained from each of the 344 volunteers by the salting-out procedure. Polymerase chain reaction and reverse dot-blot analysis were performed with the Amplitype PM PCR Amplification and Typing Kit (Polymarker Multiplex; Applied Biosystems, Foster City, CA) under conditions recommended by the manufacturer. Estimated allele frequencies in the white sample were in the usual range of that of other United States and European population groups. In any case, genotype distributions for these loci did not deviate significantly from Hardy-Weinberg equilibrium proportions. Only 1 marginally significant (0.01 < P < 0.05) association, between loci HBGG and Gc, was detected in our mulatto sample out of a total of 20 possible pairwise comparisons of the 5 loci for both data sets. Allele frequencies were significantly different (P < 0.001) at the HBGG and Gc loci when the white and mulatto samples were compared. Biologic relationship exclusion probabilities (test powers) were calculated for the data. A Brazilian database has thus been established for the loci LDLR, GYPA, HBGG, D7S8, and Gc, 5 polymerase chain reaction-based loci systems that have been shown to be a useful tool for biologic relationship identification and exclusion.  相似文献   
853.
A collaborative case-control study was conducted in France in order to determine the prevalence of alcohol, cannabinoids, opiates, cocaine metabolites, amphetamines and therapeutic psychoactive drugs in blood samples from drivers injured in road accidents and to compare these values with those of a control population. Recruitment was performed in emergency departments of six university or general hospitals and comprised 900 drivers involved in a non-fatal accident and 900 patients (controls) who attended the same emergency units for a non-traumatic reason. Drivers and controls were matched by sex and age. Alcohol was determined by flame ionization-gas chromatography, drugs of abuse (DOA) by gas chromatography-mass spectrometry with the same analytical procedures in the six laboratories, and medicines by high performance liquid chromatography with diode array detection. Blood alcohol concentration exceeding 0.5 g/l (i.e. the legal French threshold) was found in 26% of drivers and 9% of controls. In the 18-27 years age range, alcohol was the only toxic found in blood samples of 17% drivers and 5% controls, leading to an odds-ratio (OR) of 3.8. A significant relationship was found between alcohol blood concentrations and OR values. All age groups confounded, the main active substance of cannabis, Delta(9) tetrahydrocannabinol (THC), was found in 10% of drivers and 5% of controls. In the less than 27 years old, THC (>1 ng/ml) was detected alone in the blood of 15.3% drivers and of 6.7% controls, giving OR=2.5, whereas there was no link between THC blood concentrations and OR value. THC was found alone in 60% of cases and associated with alcohol in 32%, with OR=4.6 between drivers and controls for this association. The difference in morphine prevalence between drivers (2.7%) and controls (0.03%) was highly significant (P<0.001), with OR=8.2. The number of positive cases for amphetamines and cocaine metabolites was too low for reaching any interpretation. The most frequently observed psychoactive therapeutic drugs were by far benzodiazepines, that were found alone in 9.4% of drivers and 5.8% of controls, which led to OR=1.7 (P<0.01).This study demonstrates a higher prevalence of opiates, alcohol, cannabinoids and the combination of these last two compounds in blood samples from drivers involved in road accidents than in those from controls, which suggests a causal role for these compounds in road crashes.  相似文献   
854.
The AmpFlSTR Identifiler kit has recently been accepted for use in DNA databasing of forensic samples in the FBI's National DNA Index System. In the present study, we used this kit to analyze the allele distribution of 15 short tandem repeat markers (STR) in individuals living in Caracas city, Venezuela. The allele frequencies of two of these STR, D2S1338 and D19S433, have not previously been reported for this or any other Latin American population. The results indicate that for the population here studied, the 15 STR tested are useful markers for paternity testing and forensic casework.  相似文献   
855.
POPULATION: African (n=52), Mixed Ancestry (n=5), Caucasian (n=4) SAN (n=1).  相似文献   
856.
A validated gas chromatographic-mass spectrometric method for quantitative analysis of methaqualone (MTQ) in illicit preparations is reported. The method proved to have a coefficient of variation of below 5%. Four batches of seized tablets, two pairs with similar imprints, were analyzed. It was found that the average MTQ concentration in all four batches of tablets differed significantly (p = 0.01) rendering it impossible to conclude that, on the basis of MTQ concentration alone, the batches with a similar logo originated from the same manufacturer or manufacturing batch. Conversely, it can be said that in this case, the four batches originated from either different clandestine laboratories or manufacturing batches.  相似文献   
857.
Adult Hirschsprung's disease diagnosed during forensic autopsy   总被引:2,自引:0,他引:2  
We report a case of fatal Hirschsprung's disease (HD) discovered at autopsy. A 20-year-old man collapsed at home. Emergency medical personnel found him in cardiac arrest and all resuscitative efforts failed. He had a past history of chronic constipation since infancy. Forensic autopsy revealed a megacolon full of gas and stools. Microscopic examination showed absence of ganglion cells in a short segment of the rectum and enterocolitis in the left and transverse colon. HD is rarely described in adults. In many cases, patients complained of constipation since infancy but the affection remained misdiagnosed. The relative good tolerance of the disease is usually due to a short aganglionic bowel segment. Enterocolitis is a frequent and severe complication of HD in children but is rarely described in adults. This case suggests the importance of HD diagnosis in childhood in order to avoid fatal complications with forensic consequences.  相似文献   
858.
We report the case of attempted suicide with amlodipine, chlorthalidone and mefenamic acid and subsequent medical intensive care measures which resulted in total recovery of a 42-year-old male. After admission to the medical intensive care unit the intoxicated patient was deeply hypotensive and needed fluid replacement, dobutamine and norepinephrine. Additionally insulin and calcium gluconate were given. Since hypotension persisted and the patient developed oliguria, terlipressin was applied and finally showed an effect on blood pressure and on urinary output. A volume overload of 7 L in the first 24 h resulted in a pulmonary edema. The patient was started on non-invasive ventilation with continuous positive airway pressure (CPAP) and frusemide was added to the therapy with good success. Quantitative determination of amlodipine in plasma samples was performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The highest amlodipine concentrations was measured in the plasma sample collected approximately 8 h after ingestion of the drug, and was 393 microg/L. Four days later, it was possible to stop the treatment with catecholamines, at that time the amlodipine plasma concentration had declined to 132 microg/L, still tenfold higher than therapeutic (5-18 microg/L). Elimination half-life of amlodipine is approximately 55 h. After 6 days in the intensive care unit the patient was transferred to psychiatric treatment. Intensive care management and plasma levels in this intoxication case are compared to data from literature on other cases.  相似文献   
859.
A heroin distribution chain was simulated by taking three different seizures and preparing four additional samples from each seizure by adding a paracetamol-caffeine mixture in varying amounts, resulting in three different batches each composed of five samples. All of the samples from the three batches were analyzed using HPLC with a UV-PDA detector at a wavelength of 230 nm. The area ratio of various opium alkaloids, acetylation products and components were compared. From the results of the UV area ratios, the fifteen samples could readily be separated into three batches of five samples, with each batch of five samples having a common origin.  相似文献   
860.
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