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861.
We describe the gross and microscopic neuropathological changes in the brain of a 17-year-old male who died 4 days after being poisoned with cyanide. Previous reports indicate that following cyanide intoxication, the brain develops diffuse hypoxic/ischemic changes, predominantly of the basal ganglia. The case we describe here had similar features but in addition showed striking laminar necrosis of the cerebral cortex. This finding in cyanide poisoning has been previously demonstrated by neuroimaging, but not pathologically.  相似文献   
862.
Despite recent and growing media attention surrounding obesity in the United States, the so-called obesity epidemic remains a highly contested scientific and social fact. This article examines the contemporary obesity debate through systematic examination of the claims and claimants involved in the controversy. We argue that four primary groups-antiobesity researchers, antiobesity activists, fat acceptance researchers, and fat acceptance activists-are at the forefront of this controversy and that these groups are fundamentally engaged in framing contests over the nature and consequences of excess body weight. While members of the fat acceptance groups embrace a body diversity frame, presenting fatness as a natural and largely inevitable form of diversity, members of the antiobesity camp frame higher weights as risky behavior akin to smoking, implying that body weight is under personal control and that people have a moral and medical responsibility to manage their weight. Both groups sometimes frame obesity as an illness, which limits blame by suggesting that weight is biologically or genetically determined but simultaneously stigmatizes fat bodies as diseased. While the antiobesity camp frames obesity as an epidemic to increase public attention, fat acceptance activists argue that concern over obesity is distracting attention from a host of more important health issues for fat Americans. We examine the strategies claimants use to establish their own credibility or discredit their opponents, and explain how the fat acceptance movement has exploited structural opportunities and cultural resources created by AIDS activism and feminism to wield some influence over U.S. public health approaches. We conclude that notions of morality play a central role in the controversy over obesity, as in many medical disputes, and illustrate how medical arguments about body weight can be used to stymie rights claims and justify morality-based fears.  相似文献   
863.
PENDULUM--a guideline-based approach to the interpretation of STR mixtures   总被引:2,自引:0,他引:2  
Several years ago, a theory to interpret mixed DNA profiles was proposed that included a consideration of peak area using the method of least squares. This method of mixture interpretation has not been widely adopted because of the complexity of the associated calculations. Most reporting officers (RO) employ an experience and judgement based approach to the interpretation of mixed DNA profiles. Here we present an approach that has formalised the thinking behind this experience and judgement. This has been written into a computer program package called PENDULUM. The program uses a least squares method to estimate the pre-amplification mixture proportion for two potential contributors. It then calculates the heterozygous balance for all of the potential sets of genotypes. A list of "possible" genotypes is generated using a set of heuristic rules. External to the programme the candidate genotypes may then be used to formulate likelihood ratios (LR) that are based on alternative casework propositions. The system does not represent a black box approach; rather it has been integrated into the method currently used by the reporting officers at the Forensic Science Service (FSS). The time saved in automating routine calculations associated with mixtures analysis is significant. In addition, the computer program assists in unifying reporting processes, thereby improving the consistency of reporting.  相似文献   
864.
The rapid further development of computed tomography (CT) and magnetic resonance imaging (MRI) induced the idea to use these techniques for postmortem documentation of forensic findings. Until now, only a few institutes of forensic medicine have acquired experience in postmortem cross-sectional imaging. Protocols, image interpretation and visualization have to be adapted to the postmortem conditions. Especially, postmortem alterations, such as putrefaction and livores, different temperature of the corpse and the loss of the circulation are a challenge for the imaging process and interpretation. Advantages of postmortem imaging are the higher exposure and resolution available in CT when there is no concern for biologic effects of ionizing radiation, and the lack of cardiac motion artifacts during scanning. CT and MRI may become useful tools for postmortem documentation in forensic medicine. In Bern, 80 human corpses underwent postmortem imaging by CT and MRI prior to traditional autopsy until the month of August 2003. Here, we describe the imaging appearance of postmortem alterations--internal livores, putrefaction, postmortem clotting--and distinguish them from the forensic findings of the heart, such as calcification, endocarditis, myocardial infarction, myocardial scarring, injury and other morphological alterations.  相似文献   
865.
A new retrieval system for a 3D facial image database was designed and its reliability was experimentally examined. This system has two steps, firstly to automatically adjust the orientation of all 3D facial images in a database to that of the 2D facial image of a target person, and then to identify the facial image of the target person from the adjusted 3D facial images in the database using a graph-matching method. From the experimental study [M. Yoshino, K. Imaizumi, T. Tanijiri, J.G. Clement, Automatic adjustment of facial orientation in 3D face image database, Jpn. J. Sci. Tech. Iden. 8 (2003) 41-47], it is concluded that the software developed for the first step will be applicable to the automatic adjustment of facial orientation in the 3D facial image database. In 28 out of 110 sets (25.5%), the 3D image of the target person was chosen as the best match (from a database of 132 3D facial images) according to the similarity of the facial image characteristics based on the graph matching. The 3D facial image of the target person was ranked in the top of 10 of the database in 75 out of 110 sets (68.2%). These results suggest that this system is inadequate for the identification level, but may be feasible for screening method in a small database. It will be necessary to further pursue the possibility of realization of a facial image retrieval system for a large database such as suspects' facial images in future.  相似文献   
866.
The use of coxal elements for age and sex diagnosis from the skeleton is the primary and most widespread way of bringing us closer to the identity of dead individuals in archaeological and certain forensic scenarios. Diagnosis in sub-adults, especially in fetus and infant age, is not clear; and further studies are needed. This work presents the analysis of the growth of six variables in the ilium, from birth to 97 years of age, in order to evaluate its significance and its capacity for age and sex determination during and after growth. The materials used were 327 specimens from four documented Western European collections. Growth curves were calculated for the three classical variables of the ilium (width, length and index) and three new variables of the acetabulum area (horizontal and vertical diameter of the ilium acetabular surface and the ilium acetabular index). None of the curves showed a lineal growth, except those of the horizontal diameter of the ilium acetabular surface for the male series. The ilium width has the most complicated growth and it is explained by a four-degree polynomial. All the variables studied can be useful for adult sex discrimination with the exception of the ilium width and ilium acetabular index. Furthermore, the most useful variables for subadult and adult age estimation in archaeological samples, as well as in forensic samples, are the absolute measurements (ilium length and width, horizontal and vertical diameter of the ilium acetabular surface); however, the ilium width is the best variable, as this can be applied to all growth ages using both sexual series together up to 20 years of age.  相似文献   
867.
The bodies of socially isolated people may remain undiscovered in their own houses for prolonged periods. Occasionally the body is in situ for sufficient time to become skeletonised, or partially so. Medico-legal investigation of these cases is complicated by degradation and contamination of evidence. Thus, a multidisciplinary forensic investigation is recommended. The potential contributions of forensic pathology, anthropology, odontology and entomology are outlined here with reference to two cases that occurred in Victoria, Australia, in 2003. Forensic pathologists are often unable to determine the cause of death in skeletonised bodies, however, they may find evidence to support either a natural or unnatural mode of death, and they may describe skeletal pathology or trauma, and identify skeletal features to support radiological identification of the deceased. Anthropologists can provide supplementary evidence of skeletal trauma. Additionally, they can assess age, sex, stature and racial affiliation from skeletal remains. Odontologists can identify individuals through comparison with ante-mortem dental records; however, potential difficulties exist in identifying the treating dentist of a socially isolated person. Odontologists may also examine the teeth and oro-facial skeleton for trauma. Entomologists may estimate minimum death time and/or season of death. Entomological examination of insect remains may also confirm that a body has lain in situ for a considerable period.  相似文献   
868.
The 11 Y-chromosomal short tandem repeats (STRs) included in the Promega Corporation PowerPlex Y System (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385, DYS437, DYS438 and DYS439) were typed in three ethnic groups ("Andalusians", Berber and Arab) and one cosmopolitan population (Tunis) from Tunisia, summing up 247 individuals, and 139 different haplotypes. Focusing the analysis on the seven Y-STRs of the YHRD Minimal Haplotype Core (DYS385 excepted), "Andalusians" showed no differences from the Cosmopolitan and the Arab samples previously published (our Arab sample presented an extremely low haplotype diversity), but were different from the Berbers. The Berbers from Tunisia were not different from those from Morocco.  相似文献   
869.
A qualitative and quantitative analytical method was developed and validated for the determination of 49 licit and illicit drugs in oral fluid. Small oral fluid samples, volume 1mL, were collected from volunteers using a modified Omni-Sal device and the analytes were extracted from an oral fluid/buffer mixture using a single Bond Elut Certify solid phase extraction cartridge. Liquid chromatography-tandem mass spectrometry (LC-MS-MS) and gas chromatography-repetitive full scan mass spectrometry (GC-MS) were used in parallel to analyze the extracts for the targeted drugs. Extracts were analyzed by GC-MS in their underivatized form and as their pentafluoropropionyl derivatives. Deuterated internal standards were used for quantification of drugs of abuse by LC-MS-MS to minimize matrix effects. Methadone-d(9) and tumoxetine were used as the internal standards for quantification of non-derivatized and derivatized analytes respectively by GC-MS. Linearity was demonstrated over the range 5-200 ng/mL and limits of detection were less than 4 ng/mL for each drug analyzed. The method demonstrated acceptable recoveries for most of the analytes and good intra- and inter-day precision. Acquisition of data by repetitive full scan GC-MS allows the addition of further analytes to the target menu.  相似文献   
870.
A single nucleotide polymorphism (SNP) multiplex has been developed to analyse highly degraded and low copy number (LCN) DNA template, i.e. <100 pg, for scenarios including mass disaster identification. The multiplex consists of 20 autosomal non-coding loci plus Amelogenin for sex determination, amplified in a single tube PCR reaction and visualised on the Applied Biosystems 3100 capillary electrophoresis (CE) system. Allele-specific primers tailed with shared universal tag sequences were designed to speed multiplex design and balance the amplification efficiencies of all loci through the use of a single reverse and two differentially labelled allele denoting forward universal primers. As the multiplex is intended for use with samples too degraded for conventional profiling, a computer program was specifically developed to aid interpretation. Critical factors taken into account by the software include empirically determined extremes of heterozygous imbalance (Hb) and the drop-out threshold (Ht) defined as the maximum peak height of a surviving heterozygous allele, where its partner may have dropped out. The discrimination power of the system is estimated at 1 in 4.5 million, using a White Caucasian population database. Comparisons using artificially degraded samples profiled with both the SNP multiplex and AMPFISTR SGM plus (Applied Biosystems) demonstrated a greater likelihood of obtaining a profile using SNPs for certain sample types. Saliva stains degraded for 147 days generated an 81% complete SNP profile whilst short tandem repeats (STRs) were only 18% complete; similarly blood degraded for 243 days produced full SNP profiles but only 9% with STRs. Reproducibility studies showed concordance between SNP profiles for different sample types, such as blood, saliva, semen and hairs, for the same individual, both within and between different DNA extracts.  相似文献   
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