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991.
992.
Comparison techniques used in bite mark analysis are many and varied, the choice of technique depending largely on personal preference. Until recently, no one technique has been shown to be better than the others, and very little research has been carried out to compare different methods. This study evaluates and compares the accuracy of direct comparisons between suspects' models and bite marks with indirect comparisons in the form of conventional traced overlays of suspects' models or a new method using photocopier-generated overlays. Artificial bite marks in pigskin were made using standardized sets of models and recorded as photographs and fingerprint powder lifts on tape. The bite mark photographs and fingerprint lifts were coded and randomized so that a blind comparison could be made with the models, traced overlays, and photocopier-generated overlays using a modified version of the American Board of Forensic Odontology Scoring (ABFO) System for Bite Marks. It was found that the photocopier-generated overlays were significantly more accurate at matching the correct bite mark to the correct models irrespective of whether the bite mark was recorded photographically or as a fingerprint lift. The photocopier-generated overlays were also found to be more sensitive at matching the correct bite marks to the correct models than the other two methods used. The modified ABFO scoring system was able to discriminate between a correct match and several incorrect matches by awarding a high score to the correct match.  相似文献   
993.
994.
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996.
We reviewed a series of 66 deaths in Washington State between 1995-2000 in which tramadol (Ultram and Ultracet, Ortho-McNeil) was detected in the decedent's blood, in order to assess the role tramadol was determined to have played. Additionally, we reviewed a series of 83 impaired driving cases in which tramadol was detected in order to establish a non-lethal blood tramadol concentration reference range. In both populations, tramadol was consistently found together with other analgesic, muscle relaxant, and CNS depressant drugs. Death was rarely attributable to tramadol alone. However, tramadol may be a significant contributor to lethal intoxication when taken in excess with other drugs, via the potential interaction with serotonergic antidepressant medications, as well as the potential for increased CNS depression. Although the incidence of tramadol detection has increased consistently over the last eight years, there is no evidence of a corresponding increase in the number of cases in which death was attributed solely to tramadol. Blood drug concentrations in many deaths exceeded the therapeutic serum range of 0.28-0.61 mg/L; however, the concentrations overlapped almost completely with the range identified in living subjects arrested for impaired driving. These findings suggest caution in the interpretation of blood tramadol concentrations outside of the recognized therapeutic range. It also suggests that the drug, even when used in moderate excess, is not a principle cause of death in suicidal or accidental deaths.  相似文献   
997.
An HPLC-APCI-MS(/MS) method for the (trace) analysis of the most commonly encountered peroxide explosives, hexamethylenetriperoxidediamine (HMTD) and triacetonetriperoxide (TATP), has been developed. With this method, HMTD and TATP have been analyzed in the same run. (Pseudo-)molecular ions of these peroxides have been obtained as base peak under the same condition. A series of product ions was produced from these pseudo-molecular ions ([HMTD - 1]+ and [TATP + NH4]+) in the MS/MS analysis. We also pioneered in showing that a TATP molecular ion [TATP + H]+ can be observed with HPLC-MS/MS. The limit of detection for HMTD and TATP was 0.26 and 3.3 ng, respectively, on column by HPLC-MS in the Full Scan mode and 0.08 and 0.8, respectively, by HPLC-APCI-MS/MS in Selected Reaction Monitoring (single mass unit) mode. The method presented has been applied successfully for the identification of peroxides in the bulk solid state (powder sample), as well as in post-blast extracts originating from a forensic case. For the post-blast extracts, the use of tandem MS has been shown clearly to be of crucial importance for the identification and detection of the peroxide explosives.  相似文献   
998.
Gas chromatography-mass spectrometry was used to compare gasoline samples obtained from different sources based on the difference in amounts of certain components found in the headspace of gasoline using target response data. Many suspected arson cases involve comparing an ignitable liquid extracted from fire debris to a liquid found in a suspect's possession to determine if they could have had a common source. Various component ratios are proposed for determining if an unevaporated gasoline sample could have originated from the same source as an evaporated gasoline extracted from fire debris. Fifty and 75% evaporated gasoline samples were both found to contain similar ratios of certain components when compared with its unevaporated source gasoline. The results of the comparisons in this study demonstrate that for cases involving gasoline that has been evaporated up to 50% and extracted from pine, it is possible to eliminate comparison samples as originating from the same source. The results of the 75% comparisons suggest it may be possible to apply the same type of comparison to cases involving 75% evaporated gasoline.  相似文献   
999.
The utility of pulmonary interstitial emphysema (PIE) in live birth determination is not well established. Because the distinction between live birth and stillbirth may be important in criminal proceedings, we undertook this study to investigate the relationship between the histologic finding of PIE and live birth. Sixty-six cases of infant death were retrieved and compared with 21 stillborn infants. Histologic sections of the lungs were characterized as "florid PIE," "equivocal PIE," or "absent PIE." Sixteen cases of florid PIE were identified, all in live born infants. Forty-seven cases of equivocal PIE were found in 36 live born and 11 stillborn infants. In 24 cases (14 live born infants and 10 stillborns), no PIE was identified. We examined the relationship between florid PIE in infants with sudden infant death syndrome (SIDS) or "sudden unexpected death in infancy, manner undetermined" (SUDI), and also its relationship to other variables. No association was found. The presence of equivocal PIE may be an artifact of tissue processing. Florid PIE is found only in live born infants. No correlation between the presence of florid PIE and cause of death could be determined.  相似文献   
1000.
Data are reported on toxicity of a majority of non-steroid anti-inflammatory drugs (NSAD), which are the most frequently used in clinical practice and whose chemical structures are different. The action mechanism and side effects of some NSAD, in particular, of diclofenac, ibuprofen and indometacin, are also in the focus of attention.  相似文献   
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