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961.
962.
An elevated serum tryptase concentration is considered to be a specific marker for systemic mast-cell activation, a central feature of anaphylaxis, which has been observed in some cases of sudden infant death syndrome (SIDS). However, it is still unclear whether anaphylaxis is involved in the etiology for SIDS. In the present study, we measured serum tryptase levels in 21 infants with SIDS, and 14 control infants from forensic autopsy cases by Uni-CAP TRYPTASE Fluoroenzyme immunoassay system, which detects both alpha- and beta-tryptase. The assay did not show any significant elevation of tryptase levels in the SIDS group compared with controls. Additionally, increased concentrations of tryptase were not observed in any SIDS case. Our results indicated that anaphylaxis does not seem to be involved in the etiology of SIDS.  相似文献   
963.
964.
This paper presents an overview of the organisation and the results of the collaborative exercises (CE) of the European DNA Profiling (EDNAP) Group's mitochondrial DNA population database project (EMPOP). The aim of the collaborative exercises was to determine whether uniformity of mtDNA sequencing results could be achieved among different laboratories. These were asked to sequence either the complete mtDNA control region or the two hypervariable regions HVI (16024-16365) and HVII (73-340) from DNA extracts, buccal swabs or bloodstains, proceeding in accordance with the protocol and strategies used in each individual laboratory. The results of the collaborative exercises were employed to identify possible sources of errors that could arise during the analysis and interpretation of mtDNA profiles. These findings were taken as a basis to tentatively make suitable arrangements for the construction of a high quality mtDNA database. One hundred fifty mtDNA profiles were submitted to the evaluating laboratory, and disaccording profiles were classified into four groups corresponding to the source of error: clerical errors, sample mix-ups, contaminations and discrepancies with respect to the mtDNA nomenclature. Overall, 14 disaccording haplotypes (16 individual errors) were observed. The errors included 10 clerical errors, 3 interpretation problems, 2 cases of sample mix-up and 1 case of point heteroplasmic mixture, where the 2 sequencing reactions brought inconsistent base calls. This corresponds to an error rate of 10.7% in a virtual mtDNA database consisting of the collaborative exercise results. However, this estimate is still conservative compared to conclusions drawn by authors of meanwhile numerous publications critically reviewing published mtDNA population databases. Our results and earlier published concerns strongly emphasize the need for appropriate safety regulations when mtDNA profiles are compiled for database purposes in order to accomplish the high standard required for mtDNA databases that are used in the forensic context.  相似文献   
965.
Today in modern times, traumatic injuries caused by crossbows are a rarity. The largest collection of cases so far is presented in this study, consisting of four fatalities (two homicides and two suicides) and two non-fatal injuries (grievous bodily harm and an accident). All the victims were male having an age between 31 and 54. The weapons, which were used, were mainly high-performance precision crossbows with telescopic sights and hunting bolts. The parts of the body involved were the facial/head area in three of the cases and the thorax in three of them. There were either deep or total penetration injuries to the cranium and thorax with the bolt remaining in the wound in four out of six cases. The persons with non-fatal crossbow injuries exhibited comparatively few symptoms, despite the sometimes extensive involvement of the interior of the cranium (cerebrocranial penetration, in one instance). The two cases of suicide favoured the body areas often found with gun-users. The aetiological classification of crossbow injuries may be difficult after the removal of the bolt. The external morphology is strongly dependent on the type of tip used. Multiple-bladed hunting broadheads produce radiating incised wounds, whereas conical field tips produce circular to slitlike defects. Correspondingly, the external injuries can be reminiscent of the effects of a violent attack by sharp force or of a gunshot wound. The possibility, supported by clinical data, that the victim might have the ability to act or even to survive for a period of time, even with penetration of the brain, should be taken into account when the cause of death is being investigated.  相似文献   
966.
967.
Through an examination of cases of non-consensual sterilization for learning disabled persons in Canada and England, this article considers the role that law plays in framing the thoughts, beliefs, and norms that fashion the ways we think about bodies, sex, gender, and sexuality. The author asks how it is that Canadian and English law, while both claiming to protect bodily integrity, have reached opposing conclusions about whether non-therapeutic sterilization can be in a person's best interests. She hypothesizes that the answer could lie in the manner in which courts have constructed the bodies of learning disabled men and women in the sphere of sexuality and reproduction. Where the overriding concern in the sterilization cases is the containment of the sexuality of a learning disabled person perceived as "out of control" or "vulnerable to seduction", sterilization is cast as a just and humane solution that will advance the welfare of the individual concerned. Conversely, where the overriding concern is the preservation of the integrity of a law committed to the principle of equality, sterilization is thought to be a violation of the bodily integrity of the person. The author shows that these two views engender very different legal and cultural discourses about best interests and bodily integrity. The debate highlighted by the sterilization cases and the commentary surrounding them reflect larger tension within legal discourse between the commitment to liberal values and the maintenance of a particular social order.  相似文献   
968.
969.
In this study, we investigated the application of the internal standard method to determine age from aspartic acid (Asp) racemization. D-Methionine (D-Met) and D-norleucine (D-Nleu) were tested as internal standards for the purpose of validating the derivatization and gas chromatographic measurements. Using a set of standard amino acids plus the internal standards in constant volume, calibration plots with reasonable linearity (R > 0.98) were constructed. Based on the analysis of sample chromatograms, D-Met appeared to meet the criteria for internal standards, hence it was selected for use in D- and L-Asp quantification. The correlation between dentin age and D-/L-Asp ratios from the peak areas as well as from the absolute concentrations was investigated. Correlation coefficients were calculated as 0.98 and 0.90, respectively. The slight decrease in accuracy was attributed to the conversion of D-Asp/D-Met ratios to concentrations employing the calibration curves figured from pure Asp. Because the application of the internal standard method produced reproducible and precise measurements, the employment of internal standards in age estimation based on Asp racemization appears to provide quality assurance by avoiding possible errors arising from sample preparation.  相似文献   
970.
Preparation of degraded human DNA under controlled conditions   总被引:7,自引:0,他引:7  
DNA typing through analysis of short tandem repeats (STRs) and mitochondrial DNA (mtDNA) by means of the polymerase chain reaction (PCR) and sequencing are the common methods for the forensic identification of persons and reconstruction of kinship, especially when skeletal human remains have to be analyzed. Furthermore, samples typically found at crime scenes may be both quantitatively and qualitatively inadequate since they may contain very scarce and often degraded DNA due to exposure to heat, light, humidity, and microorganisms. In order to improve the performance of STR typing technology in those cases where DNA availability is limited, it would be desirable to have a source of degraded DNA with known properties. For this purpose, we have developed a method to prepare artificially degraded DNA under controlled conditions. By treatment of genomic DNA with sonication and DNAse I we have produced DNA fragments within a defined range of lengths. STR typing of this degraded DNA with a commercially available multiplex kit could only produce partial profiles as indicated by the absence of STR alleles with sizes >200 bp. This artificially degraded DNA can be used for the improvement and standardization of STR typing protocols when only highly degraded DNA is available for analysis.  相似文献   
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