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881.
Variation in the mitochondrial DNA (mtDNA) control region as detected by sequence-specific oligonucleotide (SSO) probes is described for 2282 individuals from African-American, European-American, and Hispanic subpopulations from five broadly defined regions of North America (Northeast, Southeast, Central, Northwest, Southwest). Population diversity estimates were uniformly high for all subpopulations and for each major ethnic group. Only the Pennsylvania Hispanic group was remarkable with respect to its mitochondrial DNA types, having both six low frequency population specific types (ranging from 1.2-8.6%) and three high frequency shared types (10-20% each). There was no statistically significant subpopulation heterogeneity present within any of the three major groups at either the subpopulation level or the regional level (p > 0.01). However, statistically significant heterogeneity was measured when comparing the three major groups to each other, with the variance component attributable to this large division accounting for 18.60% of the total variance (p < 0.001). Overall mtDNA is a satisfactory forensic typing locus within broadly defined African-American, European-American, and Hispanic groups from North America, based on the high diversity estimates and absence of heterogeneity, as characterized by SSO typing.  相似文献   
882.
When the anterior thoracic wall is within the hypostatic area, postmortem lividity in the region of the nipples and their immediate vicinity is less intense or absent. Where hypostatic skin haemorrhages (so-called vibices) are present, these are also found outside the areola of the nipple only. This phenomenon is visible not only externally, but is particularly pronounced on the cut surface. A possible explanation may be the different distribution pattern of connective tissue, smooth muscles and blood vessels inside and outside the areola mammae. Based on 13 cases from the forensic autopsy material--mostly drug related deaths--the macromorphological findings and their histological correlates are presented.  相似文献   
883.
The authors tested whether use of an electro shock weapon (stun gun) leaves marks on skin which can be found in an exterior examination. On pig skin such marks could not be produced postmortally. An experiment on one of the authors caused reddish skin marks which persisted for about 2 h. Inability to act as promised by the weapons' manufacturers did not occur in our experiments, exactly as previously described by other authors. Use of an air tester which shoots barbed electrodes ought to produce bleedings if the electrodes actually penetrate the skin.  相似文献   
884.
Two species of blow flies (Diptera: Calliphoridae) were reared on tissues from rabbits administered different dosages of morphine. These species, Protophormia terraenovae and Calliphora vicina are among the first wave of insects colonizing a dead body. Two series of 3 rabbits were given dosages of 10, 20, and 40 mg/h of morphine over a 3 h period via ear artery perfusion. A morphine blood level plateau was attained after 1 h of perfusion. Two other rabbits were used as controls. Samples of tissues collected from rabbits using a coelioscopic technique were determined to have morphine concentrations similar to those encountered in human overdoses and were correlated with dosages of morphine administered. All samples from control rabbits were negative for morphine. Larvae and puparia of both species were regularly collected from each rabbit for toxicological analysis. Concentrations of morphine in larvae reared on rabbit carcasses containing morphine were significantly lower than concentrations found in the tissues. There was a decrease in concentration in morphine observed in transition from feeding 3rd instar larva to puparium. A correlation between larval concentration and tissue concentration was found only in feeding 3rd instar larvae.  相似文献   
885.
886.
The Anti-Referral laws are omnipresent in the practice of health law. Perhaps as a result of their wide scope in application, those laws have had a number of unintended consequences. This Article closely examines one aspect of those laws: the exception applicable to otherwise forbidden conduct that takes place between employer and employee. The author concludes that this exception does nothing to advance the policy of the laws, has led to much confusion, and has had the unintended consequence of accelerating the business consolidation of physicians with each other and with clinics and hospitals. Consequently, she asserts that this exception should be repealed.  相似文献   
887.
This Article analyzes potential conflicts that arise from both the judicial and administrative approval processes that govern the closure of charitable hospitals through a sale of all or substantially all of their assets. Examining the recent closure attempt by the Manhattan Eye, Ear & Throat Hospital as an example, the Article highlights the various public health and corporate law issues that are raised when a not-for-profit hospital seeks closure. The Article thoroughly discusses both the statutorily and judicially required approval schemes applicable to the closure of charitable hospitals. The Article also suggests ways in which these conflicts might be avoided or remedied, as well as gives advice regarding hospital board decisionmaking.  相似文献   
888.
889.
The heterozygous condition characterized by the presence of hemoglobin AS (sickle-cell trait) occurs in approximately 8% of the American black population. Unlike the homozygous state (sickle-cell disease), sickle-cell trait is not widely recognized as a cause of life-threatening illness or death despite over 30 case reports describing fatal or serious complications of exercise in young black males with this condition. These reports identify heat stress, dehydration, viral illness, and poor physical conditioning as factors which may contribute to exertional rhabdomyolysis and sudden death, suggesting multifactorial etiology. However, since sickling is known to occur postmortem, it remains controversial as to whether the pathogenesis of these exercise related deaths involves microvascular obstruction by sickled erythrocytes. We describe three young black individuals with no significant past medical history who died following physical exertion. In all three cases, postmortem hemoglobin electrophoresis demonstrated hemoglobin AS. In none of the cases was the body temperature found to be elevated. These cases serve to remind the forensic community that, in the proper setting, sickle-cell trait must be viewed as a potentially fatal disorder.  相似文献   
890.
Morphine was detected by immunohistochemistry on sections of third stage larvae of Calliphora vomitoria (Diptera, Calliphoridae) reared on minced beef meat previously treated with morphine hydrochloride. The detection was performed with an avidin-biotin-peroxidase-complex method. Positive specimens showed specific staining of the haemolymph and a more intense immunoreaction in an area located at the limit between exocuticle and endocuticle. These results constitute an evidence of morphine accumulation inside the cuticle of Diptera larvae during their development. During the pupariation, the larval cuticle is transformed into the sclerotized puparium. This study consequently points out the possibilities of analyzing empty pupariae when suitable tissues or living necrophagous insects are absent.  相似文献   
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