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Results obtained from three commercial immunoassay kits, Abuscreen, TDx, and EMIT, commonly used for the initial test of urine cannabinoids (and metabolites) were correlated with the 11-nor-delta 9-tetrahydrocannabinol-9-carboxylic acid (9-THC-COOH) concentration as determined by GC/MS. Correlation coefficients obtained based on 26 (out of 1359 total sample population) highly relevant samples, are 0.601 and 0.438 for Abuscreen and TDx. Correlation coefficients obtained from a parallel study on a different set of 47 (out of 5070 total sample population) highly relevant specimens are 0.658 and 0.575 for Abuscreen and Emit. The immunoassay concentration levels, that correspond to the commonly used 15 ng/ml GC/MS cutoff value for 9-THC-COOH, as calculated from the regression equations are 82 ng/ml and 75 ng/ml for TDx and EMIT and 120 ng/ml and 72 ng/ml for Abuscreen manufactured at two different time periods. The difference of these calculated corresponding concentrations provides quantitative evidence of the reagent specificity differences.  相似文献   
948.
Hazards of mattresses, beds and bedding in deaths of infants   总被引:2,自引:0,他引:2  
Of 52 infants who had died suddenly and were referred to autopsy, nine had lain on adult water beds for the first time; five had died as a result of accidents; two had died on water beds; two were in beds with widely spaced slats; and one had died as a result of strangulation. Three deaths were due to overlying. Three other infants had been placed on sheepskin rugs for the first time and were found dead shortly thereafter. These infants ranged in age from 2 to 9 months, except for a severely mentally retarded nine-year-old with spastic paraplegia. We believe that a general warning should be issued concerning water beds and that soft bedding should not be used for infants. Infants should not be placed unattended or left to sleep on water beds; only beds recommended for infants should be used. Overlying of a young infant is most likely to occur on a water bed, or if the parent is obese or has consumed alcohol.  相似文献   
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The external beveling caused by an entrance gunshot wound to the skull has not been completely explained, but the mechanism is probably a combination of several factors including the angle of shot, twisting force of a rotating bullet, blow-back effect, velocity, shape and size of the bullet, outspread of the kinetic energy from the bullet, and resistance of the skull.  相似文献   
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