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971.
Neeleman J 《危机》2002,23(3):114-120
The effect of exposure to risk factors for suicidal behavior varies from place to place and from period to period. This may be due to contextual influences, which arise if individuals' suicide risk depends not only on their personal exposure to risk or protective factors, but also on how these are distributed in their social, cultural, economic, or even physical environments. There has been relatively little explicit attention in suicide research for such contextual influences even though they are an important component of the cross-level bias, which can arise when aggregate level associations are assumed to also apply in individuals and vice versa. Contextual effects are conceptually related to the issues of social selection vs. causation, population density, and network effects. Because of a lack of prospective multilevel research, it is unclear exactly which mechanisms underlie the phenomenon that the distribution of risk factors in an individual's context may affect their suicide risk above and beyond their personal exposure. A number of mechanisms, like deviancy amplification, formalization of restraints, and buffering effects of social support are proposed. Contextual effects may result in a concentration of suicide risk in persons when the risk factors they are exposed to become rare--whether spontaneously or through focused prevention. This has important but mostly overlooked implications for population-based prevention strategies.  相似文献   
972.
Wright R 《Time》2002,159(10):64
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973.
The authors report on the case of a 18-year-old student who died suddenly and unexpectedly of a pericardial tamponade after perforated ulcer-polypous endocarditis of the aortic valve. The detection of aerococcus urinae--which usually causes urinary tract infection--on the inflamed aortic valve demonstrates an unusual pathogenetic chain linking complexes of findings in the urogenital system and the heart.  相似文献   
974.
975.
The concentrations of ten elements in 209 unrelated glass specimens received as evidence were used to assess the frequencies of errors of false association (Type II errors) using several comparison criteria at specified significance levels (Type I errors). Pairwise comparisons of the samples using either the equal-variance t-test or Welch's modification (unequal variances) result in a small number of errors of false association, even when adjusting the significance level (Bonferroni correction) for multivariate comparisons. At the 95% confidence level (overall Type I error of 0.05, or individual element comparison error of 0.005), only two Type II errors are made in 21736 comparisons (0.009%) when using the equal-variance t-test for comparison of sample means. In this study, the range overlap test using three replicate measurements per specimen results in no errors of false association. Most specimen pairs in this data set are readily discriminated either by differences in the concentrations of several elements or by an extremely large difference in the concentrations of one or more element.  相似文献   
976.
Tumescent liposuction is a common cosmetic procedure that is performed as an outpatient service in physician's offices and is largely believed to be safe. The protuberant areas of the body containing the undesirable fat deposits are injected with normal saline containing lidocaine and epinephrine for pain control and hemostasis, and the waterlogged cells are suctioned out via cannula through a small incision. We recently encountered three cases in which deaths were attributed to this procedure. Two showed fat embolization in the lung and one died from fluid overload. The osmium tetroxide post-fixed lung sections showed fat emboli in the interstitial capillaries and arterioles. We reviewed the recent literature and found that pulmonary thromboemboli, fat embolization, fluid overload, and lidocaine and epinephrine intoxication are found at autopsy in many cases. Forensic pathologists responsible for determining the cause and manner of death should become familiar with the postmortem findings and risks of liposuction therapy and communicate them to their clinical colleagues and communities.  相似文献   
977.
Ketosis occurs in ketoacidosis or malnourishment. When either is suspected in relation to a death, it may be important to analyze for ketosis at autopsy. We encountered a case where starvation was suspected in a deceased nursing home resident, where the body had been embalmed prior to autopsy. Gas chromatography (GC) was unable to separate acetone from formaldehyde, a component of embalming fluid. The Acetest is a simple test that can detect acetone and acetoacetate in body fluids. We validated the Acetest with GC on vitreous. The Acetest and GC were consistent except at very low levels of acetone or acetoacetate. The sensitivity of the Acetest for acetoacetate in vitreous was 10 mg/dL, consistent with early starvation. Significant interference from embalming fluid did not occur. The Acetest was negative in the described case. The Acetest is a simple and useful test for the detection of ketosis in embalmed autopsies.  相似文献   
978.
979.
Six ninhydrin analogues containing oxygen, sulfur, and selenium substituents at the C-5 position, 5-(4-nitrophenyl)ninhydrin, and benzo[f]furoninhydrin were evaluated as fingerprint development reagents. The analogues all showed good fingerprint color development but were not superior to ninhydrin in this respect. The benzo[f]furoninhydrin complex was strongly luminescent at room temperature following zinc complexation, while the remaining analogues required cooling to -196 degrees C to produce optimum luminescence. The benzo[f]furo, nitrophenyl, and methyl selenide analogues showed the best potential as fingerprint reagents with the benzo[f]furo analogue comparing favorably with DFO.  相似文献   
980.
Antitrust law represents the principal legal tool that the United States employs to police private markets, yet it often relegates quality and nonprice considerations to a secondary position. While antitrust law espouses the belief that vigorous competition will enhance quality as well as price, little evidence exists of the practical ability of courts to deliver on that promise. In this Article, Professors Hammer and Sage examine American health care as a vehicle for advancing understanding of the nexus among competition, quality, and antitrust law. The Article reports results of a comprehensive empirical review of judicial opinions in health care antitrust litigation between 1985 and 1999, with specific attention to courts' handling of quality and other nonprice concerns. Professors Hammer and Sage conclude that, although antitrust law cannot be expected to serve as the sole oversight mechanism for industries as complex and quality dependent as health care, courts have been successful incorporating some nonprice factors into antitrust analysis.  相似文献   
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