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391.
Clarkson JE Lacy JM Fligner CL Thiersch N Howard J Harruff RC Logan BK 《Journal of forensic sciences》2004,49(5):1101-1105
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
392.
It has recently been reported that purity of illicit tablets of ecstasy (MDMA) is now high. Our objective was to confirm whether hair of drug users, who request only ecstasy from their supplier, contains MDMA in the absence of other drugs. GC-MS analysis of scalp hair segments disclosed the presence of MDMA in 19 of 21 subjects and amphetamine/methamphetamine in eight subjects. Surprisingly, seven subjects had hair levels of the MDMA metabolite, MDA, equal to or greater than those of MDMA, suggesting use of MDA in addition to that of MDMA. These amphetamine derivatives might be included by clandestine laboratories to enhance effects of the drug cocktail or because of a perception that MDA synthesis might be simpler than that of MDMA. Drug users and investigators examining possible brain neurotoxic effects of MDMA need to consider that "ecstasy" tablets can contain MDA and methamphetamine despite no demand for the drugs. 相似文献
393.
Multiplex analysis of genetic markers has become increasingly important in a number of fields, including DNA diagnostics and human identity testing. Two methods for examination of single nucleotide polymorphisms (SNPs) with a potential for a high degree of multiplex analysis of markers are primer extension with fluorescence detection, and allele-specific hybridization using flow cytometry. In this paper, we examined 50 different SNPs on the Y-chromosome using three primer extension multiplexes and five hybridization multiplex assays. For certain loci, the allele-specific hybridization method exhibited sizable background signal from the absent alternate allele. However, 100% concordance (>2000 alleles) was observed in ten markers that were typed using both methods. A total of 18 unique haplogroups out of a possible 45 were observed in a group of 229 U.S. African American and Caucasian males with the majority of samples being assigned into 2 of the 18 haplogroups. 相似文献
394.
Low explosives such as smokeless powder, black powder, and black powder substitutes have been used in illicit pipe bombings throughout the United States. Some of the newer black powder substitutes are formulated with ascorbic acid, which gradually decomposes as the powder ages, making it difficult if not impossible for the forensic chemist to identify it by traditional bulk techniques. A sensitive method for the identification of residual levels of ascorbic acid in black powder substitutes is presented. Powder samples are extracted with a mixture of acetonitrile and bis(trimethylsilyl)acetamide (BSA), which converts carboxylic acid and alcohol functional groups to trimethylsilyl esters and ethers, respectively. Samples are then analyzed by gas chromatography-mass spectrometry (GC-MS). Results have shown that trace amounts of ascorbic acid can be identified at detection limits that are well below those for traditional bulk techniques. Degradation products for ascorbic acid (hydroxylated carboxylic acids, furanones, and lactones) can also be detected. 相似文献
395.
396.
Weight force during prone restraint and respiratory function 总被引:1,自引:0,他引:1
Chan TC Neuman T Clausen J Eisele J Vilke GM 《The American journal of forensic medicine and pathology》2004,25(3):185-189
Prone maximal restraint position (PMRP, also known as hogtie or hobble) is often used by law enforcement and prehospital personnel on violent combative individuals in the field setting. Weight force is often applied to the restrained individual's back and torso during the restraint process. We sought to determine the effect of 25 and 50 lbs weight force on respiratory function in human subject volunteers placed in the PMRP. We performed a randomized, cross-over, controlled trial on 10 subjects placed in 4 positions for 5 minutes each: sitting, PRMP, PRMP with 25 lbs weight force (PMRP+25), and PRMP with 50 lbs weight force placed on the back (PMRP+50). We measure pulse oximetry, end-tidal CO2 levels, and forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1). FVC and FEV1 were significantly lower in all restraint positions compared with sitting but not significantly different between restraint positions with and without weight force. Moreover, mean oxygen saturation levels were above 95% and mean end-tidal CO2 levels were below 45 mm Hg for all positions. We conclude that PMRP with and without 25 and 50 lbs of weight force resulted in a restrictive pulmonary function pattern but no evidence of hypoxia or hypoventilation. 相似文献
397.
Recent studies have reported comparable rates of violence among men and women with mental disorder, raising important issues for clinical risk assessment. This study examines the relationship between gender and violence using data from the MacArthur Violence Risk Assessment Study. Patients in acute psychiatric wards were interviewed 5 times over the year following their discharge to the community. Results showed some differences between men and women in the violence committed immediately following discharge, with rates for men being higher. But the prevalence of violence over the 1 year was similar for female and male discharged patients. However, there were substantial gender differences in the situational context of the violence committed. Men were more likely to have been drinking or using street drugs, and less likely to have been adhering to prescribed psychotropic medication, prior to committing violence. The violence committed by men was more likely to result in serious injury than the violence committed by women, and men were more likely than women to be arrested after committing a violent act. Women were more likely to target family members and to be violent in the home. 相似文献
398.
When testifying in court, witnesses are motivated to try as hard as possible to give an accurate account. This study tested the proposition that extra effort by eyewitnesses during a memory test can lead to higher confidence ratings without any accompanying changes in accuracy. Participant-witnesses answered multiple-choice questions about a classroom visitor who had spoken 5 days earlier. In the high-motivation condition participants could earn prizes based on their memory test performance; in the low-motivation condition there were no special incentives. Although the motivation manipulation did not affect mean witness confidence, the confidence–accuracy and effort–accuracy correlations were substantially smaller in the high-motivation condition than in the low-motivation condition. Furthermore, the confidence ratings for those participants who reported expending high levels of effort in both motivation conditions were significantly higher than the confidence ratings for the low-effort participants, despite the fact that response accuracy did not differ as a function of reported effort. These findings have important implications for understanding how pressures to perform well in the courtroom can affect eyewitness confidence. 相似文献
399.
400.
ASTM standards for fire debris analysis: a review 总被引:7,自引:0,他引:7
The American Society for Testing and Materials (ASTM) recently updated its standards E 1387 and E 1618 for the analysis of fire debris. The changes in the classification of ignitable liquids are presented in this review. Furthermore, a new standard on extraction of fire debris with solid phase microextraction (SPME) was released. Advantages and drawbacks of this technique are presented and discussed. Also, the standard on cleanup by acid stripping has not been reapproved.Fire debris analysts that use the standards should be aware of these changes. 相似文献