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121.
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   
122.
123.
Suicide is second only to accidents as the most common cause of death for children and adolescents age 10 to 19 in Canada. All of the pediatric cases that were referred to the Hamilton Regional Forensic Pathology Unit from 1993 to 2002 were reviewed. For the purpose of this study, pediatric deaths were defined as deaths in the age group of 1 day up to and including 19 years of age. Specific criteria for suicide were applied to each case, independent of the manner of death issued by the coroner. The criteria were 3-fold. First, homicide had to be ruled out by the police investigation and autopsy findings. Second, the method had to be consistent with self-infliction. Finally, there had to be some evidence of suicidal intent. Questionable cases were discussed among the authors, and if reasonable intent could not be established, then the case was excluded. The autopsy and police reports were examined in detail regarding age, sex, location and method of suicide, presence of suicide notes, and any contributing psychologic factors or stressors. Of the 501 pediatric autopsies performed during the 10-year period, 31 (6%) met the criteria of suicide. The majority of cases (87%) were in older adolescents (age 15 to 19), and the male to female ratio was 2.4:1. Psychologic factors were identified in some of the cases, including depressed mood (77%), suicidal ideation (45%), previous suicide attempts (23%), and drug or alcohol problems (19%). Most of the suicides (61%) occurred in the victim's home, and 12 (39%) cases left a suicide note. In 9 cases (29%), alcohol or street drugs were detected postmortem, though in 8 cases toxicology was not performed. Hanging (48%) was the most common method of suicide, followed by firearms (13%), poisoning (10%), drowning (10%), and blunt force vehicular trauma (10%). Almost 60% of the male suicides were by hanging. No specific trend was identified in the 9 female suicides. These results were compared with similar studies within Canada and other countries. Overall, the method of suicide is dictated by what is convenient and readily available, though the acceptance of various suicide methods can change over time. Suicide prevention efforts should be tailored to address local trends.  相似文献   
124.
We present a case of an accidental autoerotic death involving the inhalation of a propane-butane gas mixture, also known as LPG (liquefied petroleum gas). A 19-year-old male was found dead in supine position in his bed in a residential accommodation one day after he was last seen alive. On a personal computer at the end of the bed, a pornographic movie was still running. On his left shoulder, an empty rubber balloon and on the bedside 2 empty "Kisag-Gas" cartridges were found. Toxicologic investigations revealed an intoxication with propane and butane, together with a recent consumption of cannabis. This case report compares the toxicologic findings with other recently published cases, and the theories of the toxic effects are discussed.  相似文献   
125.
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   
126.
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   
127.
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   
128.
Four multi-elementary metal and metalloid quantification methods using inductively coupled plasma mass spectrometry (ICP-MS) were developed and validated in human whole blood, plasma, urine and hair by means of a single preparation procedure for each sample. The ICP-MS measurements were performed using a Thermo Elemental X7CCT series and PlasmaLab software without a dynamic reaction cell. With this procedure 27-32 elements can be simultaneously quantified in biological matrices: Li, Be, B, Al, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Rb, Sr, Mo, Pd, Ag, Cd, Sn, Sb, Te, Ba, W, Pt, Hg, Tl, Pb, Bi, U. Whole blood, plasma and urine samples (0.4 ml each) were diluted with purified water, acid, triton X100 and butanol. Rhodium was used as internal standard. The urine sample results were corrected for enzymatic creatinine determination. Twenty-five milligrams hair samples were acid mineralized after a decontamination procedure and diluted as previously described for biological fluids. To be validated, each element had to show linearity with a correlation coefficient higher than 0.99. The intra-assay and inter-assay inaccuracy, measured as the variation coefficient, were below 5 and 10% respectively. Global performance was assessed by a quality control program. Our laboratory is a registered participant of the Institut National de Santé Publique du Québec (Sainte-Foy, Canada) inter-laboratory comparison program for whole blood, urine, and beard hair of non-occupationally exposed individuals spiked with selected elements. In our study multi-element metal and metalloid analysis was assessed for 27 elements in whole blood, 27 elements in plasma, 30 elements in urine and 32 elements in hair, from 0 to 25, or 250 to 1000 ng/ml, depending on the element. Quantification limits ranged from 0.002 ng/ml (U) to 8.1 ng/ml (Al) for whole blood, from 0.002 ng/ml (U) to 7.7 ng/ml (Al) for plasma, from 0.001 ng/ml (U) to 2.2 ng/ml (Se) for urine, and from 0.2 pg/mg (Tl) to 0.5 ng/mg (B) for hair. Normal values were determined in whole blood (n=100), plasma (n=100), urine (n=100), and hair (n=45) of healthy volunteers, leading to approximately 10,000 analyses. All results are presented and discussed. Clinical toxicology and forensic toxicology applications are also reported. ICP-MS has made significant advances in the field of clinical biology, particularly in toxicological analysis. This is due to the use of extremely effective equipment that permits better clinical and forensic toxicological analysis of metal and metalloid status of each individual patient.  相似文献   
129.
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   
130.
In paternity test, especially in motherless cases, the allele inherited from father (obligatory gene, OG) often cannot be determined. The paternity exclusion probability (PE) of a genetic marker is reduced considerably. Therefore, it is necessary to develop a new technique, by which the parental origin of alleles can be determined without genealogical analysis. In this paper, we explored the possibility of using parent-of-origin specific DNA methylation markers to determine the parental origin of alleles, choosing the imprinted single nucleotide polymorphism (SNP) locus rs220028 (A/G) as a model system. We typed the SNP by mutagenically separated PCR (MS-PCR). The frequencies of alleles were A = 0.5085, G = 0.4915; the unbiased heterozygosity was 0.5020. In order to discriminate between the maternal allele and paternal allele, post-digestion MS-PCR, a novel PCR based methylation analysis and SNP typing technique was developed and performed on 18 heterozygous children, and the methylated maternal allele was detected specifically. As a pilot study on the use of epigenetic markers in forensic genetics, our results demonstrated the feasibility of using parent-of-origin specific DNA methylation markers to determine the parental origin of alleles.  相似文献   
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