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991.
A case is presented of a 10 month old male who went into cardiac arrest at a local store. The infant subsequently expired and was autopsied at the Office of the Chief Medical Examiner, State of Maryland. The only remarkable finding was the detection of oxycodone in the postmortem specimens; the blood and liver oxycodone concentrations were 0.6 mg/L and 1.6 mg/kg, respectively. Oxycodone was identified and quantitated by gas chromatography-nitrogen-phosphorus detection and confirmed by full scan electron ionization gas chromatography-mass spectrometry. The medical examiner ruled that the cause of death was oxycodone intoxication, and the manner of death was homicide. The key toxicologic question in this case was whether or not it was reasonable for the infant to be exposed to oxycodone exclusively through breast milk or through an alternate source. It was concluded that, at best, there were serious concerns about the likelihood of drug exposure through consumption of breast milk.  相似文献   
992.
A simple method for analyzing nitrite in urine has been developed to confirm and quantify the amount of nitrite in potentially adulterated urine samples. The method involved separation of nitrite by capillary electrophoresis and direct UV detection at 214 nm. Separation was performed using a bare fused silica capillary and a 25 mM phosphate run buffer at a pH of 7.5. Sample preparation consisted of diluting the urine samples 1:20 with run buffer and internal standard, and centrifuging for 5 min at 2500 rpm. The sample was hydrodynamically injected, then separated using -25 kV with the column maintained at 35 degrees C. The method had upper and lower limits of linearity of 1500 and 80 microg/mL nitrite, respectively, and a limit of detection of 20 microg/mL. The method was evaluated using the National Committee for Clinical Laboratory Standards (NCCLS) protocol (Document EP10-A2), and validated using controls, standards, and authentic urine samples. Ten anions, ClO-, CrO4(-2), NO3-, HCO3-, I-, CH3COO-, F-, SO4-, S2O8(-2), and Cl-, were tested for potential interference with the assay. Interferences with quantitation were noted for only CrO4(-2) and S2O8(-2). High concentrations of Cl- interfered with the chromatography. The method had acceptable accuracy, precision, and specificity.  相似文献   
993.
A case is reported in which computer fire modeling was used to reevaluate a fire that killed three fire fighters. NIST's Fire Dynamics Simulator (FDS) was employed to model the fire in order to estimate the concentration of carbon monoxide present in the dwelling, which was the immediate cause of death of two of the fire fighters, who appear to have removed their face pieces in order to share available air. This estimate, along with an assumed respiration volume and known blood carboxyhemoglobin, was plugged into a standard equation to estimate the time of exposure. The model indicated that 27 min into the fire, the carbon monoxide concentration had already reached approximately 3600 ppm. At this concentration, and a respiration of 70 L/min, an estimated 3 to 8 min of exposure would have been required to accumulate the concentrations of carboxyhemoglobin (49, 44, and 10%) measured on the fire fighters at autopsy.  相似文献   
994.
Throughout Dr. McCrone's active professional career of over 60 years, he worked on many cases involving the forensic analysis of art. This is an overview of a small portion of these cases. Included (exposed as fakes) are the Shroud of Turin, the Vinland Map, Mayan pottery illustrations and Larionov pastels. Also included, with strong support for authentication, are three paintings attributed to Manet, Giorgione, and Leonardo da Vinci.  相似文献   
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The development of standardized assessments for competency-to-confess evaluations has remained largely neglected for the last several decades. Groundbreaking research was conducted on Miranda waivers during the late 1970s, but researchers have failed to sustain programmatic research. This critical review focuses on four published Miranda measures (Comprehension of Miranda Rights, Comprehension of Miranda Rights-Recognition, Comprehension of Miranda Vocabulary, and Function of Rights in Interrogation). When evaluated by contemporary standards, the validation of these measures is very limited. Major improvements are needed for interrater reliability, test–retest reliability, content validity, construct validity, and criterion-related validity.  相似文献   
1000.
Reported is a case of an assault causing extensive blunt force injuries in which the clinical, radiologic, and postmortem findings were all consistent with death resulting from brain damage arising from the assault. The assailant was charged with murder. Subsequent full neuropathologic (including histologic) examination revealed the unsuspected finding of a widespread meningoencephalitis but no evidence of significant traumatic brain damage. The contributions of the infective process and of the trauma to death were felt to be unclear and a guilty plea to attempted murder was accepted. This case highlights the importance of a full neuropathologic examination, including histology, in cases of trauma to the head, even when the cause of death may initially appear obvious.  相似文献   
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