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141.
The cause of drowning deaths in good swimmers may be difficult to solve. After homicide, suicide and other kinds of immersion deaths have been ruled out, not only alcohol and narcotics, but also other psychotropic substances such as thornapple and angel's trumpet should be taken into consideration--at least in adolescents and young adults. The article reports on an accidental death by drowning under the influence of tropane alkaloids after consumption of a decoction of the flowers of angel's trumpet.  相似文献   
142.
A 27-year-old man was carrying in his digestive tract 99 packages each containing about 10 g of a 86% cocaine powder. The courier died by acute cocaine intoxication due to inflation and rupture of four packages during a flight from Bogotá to Rome. At the autopsy, the external examination was unremarkable. The internal examination showed edema and generalized congestion of the organs. Toxicological analyses were performed by gas chromatography-mass spectrometry after solid phase extraction using Bond Elut Certify columns and derivatization with BSTFA/TMCS. High levels of cocaine and benzoylecgonine were found in blood (4.0 microg/mL and 17.0 microg/mL), urine (152.0 microg/mL and 512.0 microg/mL), bile (99.8 microg/mL and 54.0 microg/mL), vitreous humor (7.1 microg/mL and 5.8 microg/mL), brain (7.5 microg/mL and 3.5 microg/mL), and hair (55.5 ng/mg and 27.7 ng/mg). The presence of the cocaine and its metabolite in the hair suggested that the man was a cocaine user.  相似文献   
143.
The glucuronide conjugation is a minor pathway of ethanol metabolism. The determination of ethyl glucuronide (EG) in serum and urine has gained importance in forensic and other legal decisions. To prospectively calculate the serum concentration of this non-oxidative ethanol metabolite, the computer program developed includes a parameter fitting routine. Multiple ethanol doses can be handled.The mathematical modeling was based on the following assumptions and simplifications, respectively. A single enzyme system is responsible for ethanol conjugation at one distinct site; the distribution of EG into the systemic circulation is delayed; the elimination of EG follows first-order kinetics.The concentration of EG was calculated using three kinetic parameters: a rate constant for the first-order formation of EG from serum ethanol, a transfer constant for an obstructed transfer of EG from the formation site (FS) into the central compartment (CC) and an exponential elimination constant.The program was applied to the data collected from 21 drinking experiments. The fitting algorithm optimized the three kinetic parameters, until the sum of concentration error squares of the data points was minimized. The means+/-standard deviation of the rate constant for the first-order formation of EG from serum ethanol was 0.0011+/-0.0006 h(-1), the transfer constant for an obstructed transfer of EG from the FS into the CC was 0.43+/-0.1996 h(-1) and the exponential elimination constant was 3.0+/-1.45 h(-1).Using the range of these parameters, it is now possible to calculate minimum and maximum serum concentrations of EG based on ethanol doses and drinking times. The comparison of calculated and measured concentrations can prove the plausibility of an alleged ethanol consumption. This can be crucial when the serum ethanol concentration (SEC) itself is not meaningful.  相似文献   
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In a double-blind placebo controlled study on psychomotor skills important for car driving (Study 1), a 75 mg dose of +/- 3,4-methylenedioxymethamphetamine (MDMA) was administered orally to 12 healthy volunteers who were known to be recreational MDMA-users. Toxicokinetic data were gathered by analysis of blood, urine, oral fluid and sweat wipes collected during the first 5h after administration. Resultant plasma concentrations varied from 21 to 295 ng/ml, with an average peak concentration of 178 ng/ml observed between 2 and 4h after administration. MDA concentrations never exceeded 20 ng/ml. Corresponding MDMA concentrations in oral fluid, as measured with a specific LC-MS/MS method (which required only 50 microl of oral fluid), generally exceeded those in plasma and peaked at an average concentration of 1215 ng/ml. A substantial intra- and inter-subject variability was observed with this matrix, and values ranged from 50 to 6982 ng/ml MDMA. Somewhat surprisingly, even 4-5h after ingestion, the MDMA levels in sweat only averaged 25 ng/wipe. In addition to this controlled study, data were collected from 19 MDMA-users who participated in a driving simulator study (Study 2), comparing sober non-drug conditions with MDMA-only and multiple drug use conditions. In this particular study, urine samples were used for general drug screening and oral fluid was collected as an alternative to blood sampling. Analysis of oral fluid samples by LC-MS/MS revealed an average MDMA/MDEA concentration of 1121 ng/ml in the MDMA-only condition, with large inter-subject variability. This was also the case in the multiple drug condition, where generally, significantly higher concentrations of MDMA, MDEA and/or amphetamine were detected in the oral fluid samples. Urine screening revealed the presence of combinations such as MDMA, MDEA, amph, cannabis, cocaine, LSD and psilocine in the multiple-drug condition.  相似文献   
147.
The aim of the present investigation was to reconstruct the chronological age based on the dental developmental stages of third molars evaluated on orthopantomograms. A total of 1175 orthopantomograms were assembled from patients of Caucasian origin between 16 and 22 years of age. Each third molar present was scored by two observers according to a 10-stage developmental scale. The kappa statistics measured the intra- and inter-observer reliability. The general statistical analysis was based on multiple regression analysis in order to obtain multiple regression formulas for dental age estimation based on the number of third molars present on the evaluated orthopantomogram. No regression models were statistically significant when there was only one-third molar present because of the relatively small number of orthopantomograms that fitted this criterion. A strong agreement was found between the intra- and inter-observer measurements. The statistical analysis revealed both for males and females high Pearson correlation coefficients between contralateral third molars and smaller coefficients between antimeres. The obtained multiple regression formulas are only applicable in certain specified conditions, for instance when four third molars are present the following formulas should be used in a Caucasian male "age=10.2000+0.5122UL+0.5273LL" (developmental stage of upper and lower left third molars) or in case of a female "age=13.6206+0.1933UR+0.5080LR" (developmental stage of upper and lower right third molars). This investigation revealed that the chronological age of a Caucasian individual may be estimated based on regression formulas with a S.D. of 1.52 or 1.56 years for males and females, respectively, when all four third molars are present.  相似文献   
148.
The paper presents final results of the studies concerning the usefulness of knee, ankle, hip, pelvis and neck injuries in reconstructing the circumstances of car-to-pedestrian accidents. Each type of injuries was evaluated with regard to possible reconstruction of the victim's position (upright or recumbent) at the moment of collision and in the upright hits-the side of the pedestrian's body hit. In each group, a chance of proper reconstruction of the pedestrian's location (which determined the frequency of injury pattern assumed as the typical one of a given position or impact side) and error risk (percentage of cases in which the injury pattern showed improper position or impact side) were calculated. These data were compared with similarly calculated possibilities of deducing based on the classical "bumper" injuries to soft tissues and "bending" fractures of the lower limb bone diaphyses. It was shown that the bone bruises within the knee epiphyses were very specific evidence for upright hits as they confirm the limb load by body mass at the moment of pathological dislocation of joint structures on impact. The evidential value of knee injuries was found to be similar to that of other "classical" methods based on bumper injuries or even higher in lateral and front hits. The injuries to the remaining structures were less frequently found and their correlation with the victim's position or impact side was lower. Nevertheless, once the whole complex of these injuries is taken into consideration the chances of proper reconstruction of the pedestrian-vehicle location increase and the risk of opinion error is minimized.  相似文献   
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An intoxication following administration of morphine, tramadol and atracurium in a suicide case is reported. The route of administration and the amount of the particular drug were known from the investigation of the death scene and the findings of the postmortem examination. Tramadol was present in the gastric contents as well as in blood, liver, kidney and brain samples, whereas the drug could not be detected in muscle. All body fluids and tissues investigated contained morphine as well as its 3- and 6-glucuronides with the exception of muscle tissue. The concentrations of morphine and its glucuronide metabolites were determined by LC/MS following solid phase extraction. Interestingly, the concentration of M6G in brain, liver and kidney were close to the concentration of M3G in the particular tissue. This phenomenon might be explained by a preferential hydrolysis of M3G or by a preferential formation of M6G postmortem. Measurement of morphine and M6G in femoral blood and cerebrospinal fluid may be a useful indicator in rapid deaths.  相似文献   
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