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Toxicological findings in all military aircraft fatalities investigated by the Division of Forensic Toxicology at the Armed Forces Institute of Pathology from 1986-1990 are presented. Carbon monoxide saturation levels greater than 10% were found in 4% of the 535 cases where appropriate specimens were collected. Positive ethanol findings were more indicative of postmortem formation than antemortem consumption. In only 1 case were abused drugs (cannabinoids in a passenger) detected. Other drugs identified included nicotine, chloroquine and over-the-counter analgesic agents, antihistamines and sympathomimetic drugs. 相似文献
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This presentation attempts to demonstrate the value of the use of improved methods in the excavation of buried bodies involved in a criminal investigation. Care in the removal of the skeleton and proper recording will document the interrelationship of all objects found in and around the grave and can, to a certain extent, recreate the event. Carelessness will result in evidence being irretrievably lost. The crime scene investigator's problem, arachaeologically, includes the nature of the remains, dating the time of burial, and techniques of excavation. Archaeological recovery techniques should be adopted in homicide investigation involving buried bodies. 相似文献
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The role of the federal government in groundwater regulationis likely to increase over the next few decades. A combinationof eventsincluding recent federal court decisions, pastfederal intervention in state groundwater utilization, the publicpronouncements by a variety of federal actors, and increasingconcern over the inability of states to control overdraftingallsuggest that the federal role in groundwater management maybe increasing. These events are examined here, and it is arguedthat, without change in state groundwater management practicesto mitigate the negative effects of state competition for groundwater,federal intervention in groundwater management seems likely. 相似文献
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False negative and false positive radioimmunoassay results for cannabinoids in urine are reported. Such results occur infrequently and appear to be due to non-specific binding of the radiolabel by interfering substances, possibly proteins, in the specimens. False negatives arise when these substances and the non-specifically bound radiolabel are precipitated by polyethylene glycol in the separation stage of the assay, increasing the radioactivity in the bound fraction and thus lowering the assay result. False positives occur when the interfering substances and non-specifically bound radiolabel remain in solution during the separation stage, increasing the radioactivity in the free fraction and giving an erroneously high result. False positives could also occur in assays involving solid-phase antibodies or second-antibody separations. Methanol treatment of the samples prior to analysis precipitates the interfering substances and eliminates the aberrant effect. The interfering substances have not been identified through common serum proteins and semen have been excluded. No common factor in the circumstances of the cases that can account for the results has been identified. 相似文献
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