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991.
A clear positive case for anabolic steroids doping was confounded by alleged urine tampering during doping control procedures. Review of the chain of custody showed no flaws, but nevertheless the athlete was adamant that the urine sample should be analyzed for DNA in order to support her contention that she was not the donor of the sample. The results obtained showed that the urine sample that scored positive for steroids contained nuclear DNA that could not be matched to the DNA obtained from the athlete's blood. On the other hand, the same urine sample contained mitochondrial DNA whose nucleotide sequences spanning the hyper variable regions HV1 and HV2 proved to be identical to those determined in mitochondrial DNA amplified from the athlete's blood. The occurrence of an extraneous genotype is compatible with exogenous nuclear DNA admixture to the athlete's urine. Alternatively, taking in consideration the mitochondrial DNA, we could not exclude that a sibling or a maternal relative of the athlete could have acted as a donor of the urine utilized for doping control and DNA analysis. Both situations point to possible tampering of the urine by the athlete. Adjudication at CAS maintained previous national and international federation decision that there was no proof of a chain of custody flaw to justify the athlete's allegation of urine substitution after collection.  相似文献   
992.
993.
Samples containing DNA from two or more individuals can be difficult to interpret. Even ascertaining the number of contributors can be challenging and associated uncertainties can have dramatic effects on the interpretation of testing results. Using an FBI genotypes dataset, containing complete genotype information from the 13 Combined DNA Index System (CODIS) loci for 959 individuals, all possible mixtures of three individuals were exhaustively and empirically computed. Allele sharing between pairs of individuals in the original dataset, a randomized dataset and datasets of generated cousins and siblings was evaluated as were the number of loci that were necessary to reliably deduce the number of contributors present in simulated mixtures of four or less contributors. The relatively small number of alleles detectable at most CODIS loci and the fact that some alleles are likely to be shared between individuals within a population can make the maximum number of different alleles observed at any tested loci an unreliable indicator of the maximum number of contributors to a mixed DNA sample. This analysis does not use other data available from the electropherograms (such as peak height or peak area) to estimate the number of contributors to each mixture. As a result, the study represents a worst case analysis of mixture characterization. Within this dataset, approximately 3% of three-person mixtures would be mischaracterized as two-person mixtures and more than 70% of four-person mixtures would be mischaracterized as two- or three-person mixtures using only the maximum number of alleles observed at any tested locus.  相似文献   
994.
Infectious microorganisms are important to multiple communities engaged in biodefense and biosecurity, including the agencies responsible for health, defense, law enforcement, agriculture, and drug and food safety. Many agencies have created lists of high priority infectious microorganisms to prioritize research efforts or to formally control the possession and distribution of specific organisms or toxins. However, the biological classification of infectious microorganisms is often complex and ambiguous, leading to uncertainty and confusion for scientists involved in biosecurity work. To address this problem, we created a database, known as the Microbial Rosetta Stone, which resolves many of these ambiguities and includes links to additional information on the microbes, such as gene sequence data and scientific literature. Here we discuss the efforts to coordinate organism names from pathogen lists from various governmental agencies according to biological relatedness and show the overlap of high-priority organisms from multiple agencies. To our knowledge, this is the first comprehensive coordination of pathogens, synonyms, and correct taxonomic names. The organized tables and visual aids are freely available at http://www.microbialrosettastone.com. This website provides a single location where access to information on a broad range of disease-causing organisms and toxins is available to members of the biosecurity community.  相似文献   
995.
Selenium is a ubiquitous element in the environment essential to the human diet and widely utilized in industrial processes. Fatal human selenium intoxication is rare. The authors report a case in which investigators recovered a bottle of gun-bluing agent beside a 24-year-old man. He exhibited signs and symptoms typical of acute selenium intoxication presenting with nausea and vomiting, followed by pulmonary edema and rapid cardiovascular collapse approximately 3 to 4 h after ingestion. Classic electrocardiographic (EKG) changes, which have been reported to occur in acute selenium intoxication, included sinus tachycardia with ST wave alteration. Toxicological results confirmed elevated blood and tissue concentrations. The cause of death was ascribed to acute selenium intoxication, which ensued rapidly after oral consumption. The manner of death was suicide. This case report, which presents an overview of acute and chronic selenium poisoning, underscores the value of thorough toxicologic analyses of tissue and body fluids in humans.  相似文献   
996.
The forensic pathologist increasingly relies on the forensic anthropologist to be the consulting expert in human identification. Likewise, if identification is not possible from visual inspection of skeletal remains, the forensic biologist may be called upon to conduct DNA analysis. The possibility of downstream DNA testing needs to be considered when skeletal preparation techniques are employed to deflesh human remains, as they have the potential to strongly impact genetic analyses and subsequent identification. In this study, three cleaning techniques, boiling bone in water, in bleach, and in powdered detergent/sodium carbonate, were tested for their effect on nuclear and mtDNA recovery from a variety of human and non-human bones. A statistically significant reduction in DNA yields occurred in non-human bones cleaned with bleach, and DNA degradation was apparent electrophoretically. The human bones also showed much lower yields from bleach cleaning, while the detergent/carbonate method allowed the largest segments of DNA to be amplified, indicating it may have a less degradative effect on bone DNA than either of the other cleaning processes.  相似文献   
997.
The psychiatrist's assessment of criminal responsibility of an accused in court for an act of crime has always been a matter of great difficulty. In 1997, clause 300a was incorporated into the Penal Code of Israel, thereby permitting a more lenient punishment for murder than mandatory life imprisonment. The clause includes the definition of what is meant by "severe mental disorder" and "significantly restricted capacity" by the defendant to understand the criminal nature of his or her act and to refrain from committing it. Usage of the concepts "disorder" and "significantly restricted capacity" in addressing the issue of diminished responsibility of the mentally ill is new to the Israeli legal code. The emergence and evolvement of the above concepts are presented through a historical review of the Israeli encoded law concerning mental illness, analyzed from a psychiatric perspective.  相似文献   
998.
In this article, we assess the recent performance of the French state at containing costs in health care using political science concepts such as path dependency and incentives, which are central to an economic approach. The article focuses on institutional capacities and cultural immobilism and attempts to lay bare the tensions at play in seizing (or not) opportunities for structural change. In particular, we attempt to delineate what constitutes real change in this policy arena (big reforms versus the accumulation of many small policy movements) and to understand the variables at play in the coming together of conjunctures that provide for the big, as well as the underlying structures that allow the accumulation of the small. Except in cases of favorable conjuncture, the analysis bodes very ill for nonincremental reform and, indeed, for significant change over the long term.  相似文献   
999.
Risk adjustment (RA) consists of a series of techniques that account for the health status of patients when predicting or explaining costs of health care for defined populations or for evaluating retrospectively the performance of providers who care for them. Although the federal government seems to have settled on an approach to RA for Medicare Advantage programs, adoption and implementation of RA techniques elsewhere have proceeded much more slowly than was anticipated. This article examines factors affecting the adoption and use of RA outside the Medicare program using case studies in six U.S. health care markets (Baltimore, Seattle, Denver, Cleveland, Phoenix, and Atlanta) as of 2001. We found that for purchasing decisions, RA was used exclusively by public agencies. In the private sector, use of risk adjustment was uncommon and scattered and assumed informal and unexpected forms. The most common private sector use of RA was by health plans, which occasionally employed RA in negotiations with purchasers or to allocate resources internally among providers. The article uses classic technology diffusion theory to explain the adoption and use of RA in these six markets and derives lessons for health policy generally and for the future of RA in particular. For health policy generally, the differing experiences of public and private actors with RA serve as markers of the divergent paths that public and private health care sectors are pursuing with respect to managed care and risk sharing. For the future of RA in particular, its history suggests the need for health service researchers to consider barriers to use adoption and new analytic technologies as they develop them.  相似文献   
1000.
Carbon monoxide (CO) poisoning as a cause of death is well documented in industrialized countries. The objective of this study was to compare demographic data in deaths due to accidents (in fires) and suicides in the same population between 1988 and 1998. Furthermore, the potential effect of a community wide education effort regarding safety in the home was assessed. Postmortem reports were reviewed for all deaths examined at the Office of the Cuyahoga County Coroner in Cleveland, OH, USA. During the study period, there were 209 accidental deaths due to fires in the home (6.5% of all accidents in the home) and 182 CO deaths by suicide (9.8% of all suicides). Demographic characteristics of the two groups differed: while males represented the majority of cases in both groups (55% of accidents, 70% suicides), race specific death rates were higher for whites than blacks (18/100,000 white, 3/100,000 black) in suicides compared with 29/100,000 deaths for blacks and 11/100,000 for whites in accidental cases. Fire deaths were prevalent in the young (0-9 years) and old (>60) whereas in the suicide group the age specific death rate was highest for those over 70 years. The majority of fire deaths occurred in the city of Cleveland but suicides were prevalent in the suburbs. More fire deaths occurred in December than any other month whereas more suicides occurred in April. In 1992, there was a community wide effort to provide free smoke detectors to residents in Cleveland. In 1992, there were 4.2/100,000 fire deaths in the city. This decreased to 0.6/100,000 in 1996, increased to 1.2/100,000 in 1997 followed by a decrease to 0.8/100,000 in 1998. This suggested that the program may have aided in decreasing these types of deaths. Deaths due to fires in the suburbs were <1/100,000 throughout the study period.  相似文献   
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