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681.
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684.
Hull MJ Juhascik M Mazur F Flomenbaum MA Behonick GS 《Journal of forensic sciences》2007,52(6):1383-1388
Fatalities associated with fentanyl hydrochloride are increasingly seen in Massachusetts. Between September 2005 and November 2006, 5009 medicolegal investigations associated 107 deaths with licit or illicit fentanyl use, along with a co-detection of an opiate/opioid or cocaine/benzoylecognine, or both. Deaths associated with illicit fentanyl use occur in younger people (39.4 vs. 61.5 years) with higher fentanyl (17.1 ng/mL vs. 4.4 ng/mL) and lower morphine (76.9 ng/mL vs. 284.2 ng/mL) postmortem blood concentrations, and more frequent cocaine co-intoxication (65% vs. 3%), than deaths associated with illicit fentanyl use. A wide range of postmortem blood concentrations of fentanyl was detected (trace-280 ng/mL), with a minimum concentration of 7 ng/mL of fentanyl strongly associated with illicit use of fentanyl in poly-drug cases. The most commonly detected opiates/opioids in illicit fentanyl users were: morphine (29%), oxycodone (14.5%), and methadone (14.5%). Ethanol, cannabinoids, diazepam, citalopram, and diphenhydramine were each detected in greater than 10% of the licit fentanyl cases. Most fentanyl abusers died at their own home and their deaths were most often classified as accidental. Mapping of primary residences of decedents revealed conspicuous clustering of the illicit fentanyl use cases, as opposed to the random pattern in licit use cases. Fentanyl misuse is a public health problem in Massachusetts. 相似文献
685.
Validation of new methods 总被引:8,自引:0,他引:8
Reliable analytical data are a prerequisite for correct interpretation of toxicological findings in the evaluation of scientific studies, as well as in daily routine work. Unreliable analytical data might not only be contested in court, but could also lead to unjustified legal consequences for the defendant or to wrong treatment of the patient. Therefore, new analytical methods to be used in forensic and/or clinical toxicology require careful method development and thorough validation of the final method. This is especially true in the context of quality management and accreditation, which have become matters of increasing relevance in analytical toxicology in recent years. In this paper, important considerations in analytical method validation will be discussed which may be used as guidance by scientists wishing to develop and validate analytical methods. 相似文献
686.
In the last years the research output of forensic medicine has sometimes been regarded as insufficient and as of poor quality, especially when parameters as impact factors and external funding were taken into account. However, forensic medicine has different tasks compared to clinical medicine. The main difference between basic subjects, clinical and forensic medicine is not a lack of scientific efficiency in forensic medicine but is a result of the questions asked, the available methods and specific aims. In contrast to natural-scientific research, forensic science has furthermore important intersections with arts and socio-scientific disciplines. Etiologic and pathogenetic research is of only limited relevance in forensic medicine. Thus, forensic medicine is excluded from these research fields, which are mainly supported by external funding. In forensic medicine research mainly means applied research regarding findings, the probative value and reconstruction as well as examination at different points of intersection between medicine and law. Clinical types of research such as controlled randomised, prospective cross-sectional, cohort or case-control studies can only rarely be applied in forensic medicine due to the area specific research fields (e.g. thantatology, violent death, vitality, traffic medicine, analytical toxicology, hemogenetics and stain analysis). The types of studies which are successfully established in forensic medicine are comparison of methods, sensitivity studies, validation of methods, kinetic examinations etc. Tasks of research in forensic medicine and study types, which may be applied will be addressed. 相似文献
687.
Wehner F Stiegler A Schulz MM Heinz-Dieter W Martin D 《Archiv für Kriminologie》2007,219(5-6):180-190
In cases of penetrating stab wounds by different knives it is highly relevant to prove which knife caused which injury, especially if one of the injuries was lethal. This is possible by immunocytochemical examination of cellular material remaining on the injuring blade because some organs have organ-specific antigen determinants such as alpha-l-fetoprotein in the liver cells or cardiac troponin I in the heart muscle cells, to which antibodies can bind. Even when penetrations occur through several layers of clothing, enough cells from the injured organ remain on the blade of a knife to allow immunohistochemical examination. These cells can be collected by means of adhesive film or wiping the blade and can be stained immunocytochemically. The organ specificity of the examined proteins allows proof of their origin. The present study shows that immunocytochemical alpha-l-fetoprotein and cardiac troponin I staining of the cells remaining on a knife blade enables proof of whether the knife blade injured the heart or the liver, or both. 相似文献
688.
The authors report on a suicide of a 41-year-old man with acetylsalicylic acid. According to his own statement the man had taken about 200 tablets of Aspirin (65 g acetylsalicylic acid) and initially showed no symptoms of intoxication. 4-5 hours after ingestion he vomited twice, but clear intoxication symptoms like convulsions and cardiac arrhythmia occurred not earlier than 11 hours after ingestion. Resuscitation by the emergency physician was not successful. The chemical-toxicological analysis (HPLC-DAD) of blood samples taken in the hospital approximately 12 h after ingestion showed salicylate in concentrations of 475 mg/L to 557 mg/L. The post-mortem concentrations of salicylate were within the lethal-toxic range, i.e. 762 mg/L in heart blood and 215 mg/L in femoral blood. All tested organs contained equally lethal salicylate levels (e.g. 503 mg/L in the liver and 251 mg/L in the brain). 相似文献
689.
When one thinks of the so-called barrel or wide-angle distortion, grotesquely warped faces may come to mind. For less extreme cases with primarily inconspicuous facial proportions, the question, however, still arises whether there may be a resulting impact on the identification of faces. In the first experiment, 3 test persons were photographed at a fixed camera-to-object distance of 2 m. In the second experiment, 18 test persons were each photographed at a distance of 0.5 m and 2.0 m. For both experiments photographs were taken from a fixed angle of view in alignment with the Frankfurt Plane. An isolated effect of the focal length on facial proportions could not be demonstrated. On the other hand, changes in the camera-to-object distance clearly influenced facial proportions and shape. A standardized camera-to-object distance for passport photos, as well as reconstruction of the camera-to-object distance from crime scene photos and the use of this same distance in taking photographs for comparison of suspects are called for. A proposal to refer to wide-angle distortion as the nearness effect is put forward. 相似文献
690.
When a corpse is found that cannot be identified, one of the forensic tasks is to determine how old the person was when she or he died. To solve this frequently asked question in forensic practice, the enamel protein amelogenin was marked immunohistochemically in 249 extracted teeth. Amelogenin is already produced during prenatal development and is gradually used up throughout life into old age. Hence, the demonstrability decreases with age. The extent of the labelling can be quantified by measuring the mean optical density (MOD). While it is not possible to determine the age on the basis of the mean optical density measurements alone, logistic regression of the MOD together with dichotomisation of the teeth according to age allows statements as to whether the person was younger or older than 30 years. 相似文献