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961.
Hemorrhagic disease of the newborn (HDN) is usually a self-limiting hemorrhagic disorder of childhood that occurs as a result of vitamin K deficiency. It may be defined as early or late form depending on the time of onset related to birth. HDN is recognized as one of several bleeding disorders that can mimic the findings of nonaccidental head injury and may lead to a mistaken diagnosis of child abuse. We present a single fatal case of late-onset HDN with illustration of hematologic assays that can be performed to assist the pathologist in making the correct diagnosis of HDN.  相似文献   
962.
A statistical investigation of the relationship between firing range and the amount and distribution of gunshot residue (GSR), used automated image analysis (IA) to quantify GSR deposit resulting from firings into pig skin, from distances ranging between contact and 45 cm. Overall, for a Ruger .22 semi-automatic rifle using CCI solid point, high velocity ammunition, the total area of GSR deposit on the skin sections decreased in a non-linear fashion with firing range. More specifically there were significant differences in the amount of GSR deposited from shots fired at contact compared with shots fired from distances between 2.5 and 45 cm; and between shots fired from a distance of 20 cm or less, with shots fired at a distance of 30 cm or more. In addition, GSR particles were heavily concentrated in the wound tract only for contact and close range shots at 2.5 cm, while the particle distribution was more uniform between the wound tract and the skin surfaces for shots fired from distances greater than 2.5 cm. Consequently, for future scientific investigations of gunshot fatalities, once standards have been established for the weapon and ammunition type in question, image analysis quantification of GSR deposited in and around the gunshot wound may be capable of providing a reliable, statistical basis for estimating firing range.  相似文献   
963.
Mitochondrial DNA regions HVI and HVII population data.   总被引:2,自引:0,他引:2  
Data from 1393 unrelated individuals have been compiled from eight population groups: African Americans, Africans (Sierra Leone), U.S. Caucasians, Austrians, French, Hispanics, Japanese, and Asian Americans. The majority of the mtDNA sequences were observed only once within each population group (i.e., ranging from a low of 60.3% (35/58) of the Asian American sequences to a high of 85.3% (93/109) of the French sequences). Genetic diversity ranged from 0.990 in the African sample to 0.998 in African Americans. Random match probability ranged from 2.50% in the Asian American sample to 0.52% in U.S. Caucasians. The average number of nucleotide differences between individuals in a database is greatest for the African American and African samples (14.1 and 13.1, respectively), and the least variable are the Caucasians (ranging from 7.2 to 8.4). Substitutions are the predominate polymorphism, and at least 92% of the substitutions are transitions. The most prevalent transversions are As substituted for Cs and Cs substituted for As. For most population groups these transversions occurred predominately in the HVI region; however, the African, African American, and Hispanic samples also demonstrated a large portion of their C to A and A to C transversions in the HVII region (at sites 186 and/or 189). Most insertions occur in the HVII region at sites 309.1 and 315.1, within a stretch of C's. Insertions of an additional C are common in all population groups. The sequence data were converted to SSO mtDNA types and compared with population data on Caucasians, Africans, Asians, Japanese, and Mexicans described by Stoneking et al. [M. Stoneking, D. Hedgecock, R.G. Higuchi, L. Vigilant, H.A. Erlich, Population variation of human mtDNA control region sequences detected by enzymatic amplification and sequence-specific oligonucleotide probes, Am. J. Hum. Genet. 48 (1991) 370-382] using an R x C contingency table test. Differences between major population groups (i.e., between African, Caucasian, and Asian) are quite evident, and similar ethnic population groups carried similar SSO polymorphism frequencies. There were only a few SSO types that showed significant differences between subpopulation groups. The SSO data alone can not be used to describe the population genetics with complete sequence data. However, the results of the SSO comparisons are similar to other analyses, and differences in sequence data in regions HVI and HVII are greater between major population groups than between subgroups.  相似文献   
964.
Prostate specific antigen (PSA, also known as p30), a glycoprotein produced by the prostatic gland and secreted into seminal plasma, is a marker used for demonstrating the presence of seminal fluid. Methods for the detection of PSA include Ouchterlony double diffusion, crossover electrophoresis, rocket immuno-electrophoresis, radial immunodiffusion, and ELISA. The extremely sensitive ELISA technique can detect PSA in concentrations as low as approximately 4 ng/mL. However, all these techniques are cumbersome and time consuming to perform in forensic laboratories, especially when only a few samples per week are processed. Various membrane tests are currently used in clinical settings to screen a patient's serum for the presence of PSA at levels greater than 4 ng/mL. In this study we evaluated three immunochromatographic PSA membrane tests by analyzing semen stains stored at room temperature for up to 30 years, post-coital vaginal swabs taken at different time after intercourse, semen-free vaginal swabs, and various female and male body fluids, including urine. The data demonstrate that PSA membrane test assays offer the same sensitivity as ELISA-based tests and provide a rapid approach for the forensic identification of seminal fluid. Furthermore, when the supernatant from a DNA extraction is used for the assay, there is essentially no DNA consumption for determining the presence of PSA in a forensic sample.  相似文献   
965.
Chorionic villus sampling (CVS), prior to pregnancy termination (pre-termination CVS), is suggested as a tool for forensic paternity testing. Unlike the abortion material, which consists of ruptured tissues of fetal and maternal origin, extra-embryonic membranes obtained through CVS can provide an uncontaminated source of fetal tissue for genotyping. We discuss the possibility of confined placental mosaicism (CPM) and its implications on the polymerase chain reaction (PCR) based analyses of short tandem repeats (STRs) and the D1S80 loci.  相似文献   
966.
Few studies of autopsy findings of persons dying of head and neck injuries in cyclists have been published. We performed a retrospective analysis of injury severity and the relation between head and neck injuries and helmet use. Seventy-six bicyclists and motorcyclists were collected from among the forensic autopsy at the Jikei University School of Medicine. From autopsy findings and accident reports, the abbreviated injury scale (AIS) and the injury severity score (ISS) were calculated and analyzed epidemiologically. As a result, helmet use significantly decreased the severity of head and neck injuries but had no effect on overall injury severity or the severity of injuries to other body regions. Furthermore, helmets had little effect on injuries remote from the point of impact, injuries resulting from angular acceleration, or injuries at the junction of the head and neck. These findings may be useful for both forensic pathologists and clinicians evaluating injuries in bicyclists and motorcyclists.  相似文献   
967.
Acetaminophen (paracetamol), a widely used analgetic drug, is well tolerated at therapeutic doses, but may cause severe hepatotoxicity when ingested in large overdose. Self-poisoning is still very popular in adults and accidental ingestion of one single overdose occurs occasionally in children. In contrast, lethal intoxication in children after repeated administration of therapeutic doses is a very rare event. This case report describes an iatrogenic acetaminophen overdosing in a 5-year-old child receiving 8.5 g acetaminophen in 48 h. Fulminant liver failure developed within 60 h. Autopsy findings included panlobular liver cell necrosis. Acetaminophen serum levels were rather low compared to cases with ingestion of one single overdose. Postmortem diagnosis of chronic acetaminophen intoxication as cause of death should include the clinical history as well as, if available, the calculated drug serum half-life.  相似文献   
968.
The article compares three memoirs of genetically based disability: Lisa Roney's sweet, invisible body, Georgina Kleege's Sight Unseen, and Alice Wexler's Mapping Fate. The essay explores the tension between the narrow and the broad construction of disability, as demonstrated by the 1999 Supreme Court rulings on the ADA and as experienced by these three memoirists. It concludes that the approach of narrative bioethics, as exemplified by such a study of disability and illness narratives, can offer the medical and public policy community a valuable alternative perspective on genetic disability not as an incapacity, but as a set of social relations and practices.  相似文献   
969.
The "Philosophers' Brief," penned by six of today's most influential philosophers, was submitted as an amicus curiae brief to the Supreme Court as it prepared to consider the cases of Washington v. Glucksberg and Vacco v. Quill. It set precedent as the first such brief submitted by a group representing itself solely as moral philosophers. The brief became an overnight gold standard statement of the liberal philosophical understanding of the relationship of the State to so-called 'private morality.' The main thesis of the brief is that physician-assisted suicide regards the deeply personal event of death, and that individuals have a constitutionally guaranteed right to make decisions for themselves about the intimate details of their lives. In this article, James DuBois calls this the 'liberty thesis,' and he argues that the brief's application of this principle is both contradictory and impracticable. The contradiction arises as the brief proposes restrictions on the right to physician-assisted suicide--restrictions that require the State to abandon neutrality on intimate value judgments about life's worth. The impracticability arises insofar as the brief fails to leave room for a compelling State interest in promoting a minimal level of public virtue. Ironically, one of the strongest arguments that can be proffered on behalf of a State interest in preserving a minimal level of public virtue stems from its role in safeguarding human liberty.  相似文献   
970.
A population study on two new short tandem repeat (STR) loci D2S1338 (a tetranucleotide repeat) and Penta E (a pentanucleotide repeat) was performed on 208 unrelated Italian Caucasians. The DNA was amplified by polymerase chain reaction (PCR) and separation and detection of the amplified STR fragments were carried out by use of a PE/ABD PRISM 377 DNA Sequencer 377 automated system (Applied Biosystems Division/Perkin-Elmer). Both loci meet Hardy-Weinberg expectations. There is no evidence for departures from expectations between the two loci. The combined Probability of Discrimination and Probability of Exclusion for the two STR loci are 0.999155 and 0.944925, respectively. The results demonstrate that these two regions can be useful for differentiating among individuals, particularly in concert with other STR loci.  相似文献   
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