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951.
Childhood sporting deaths   总被引:1,自引:0,他引:1  
  相似文献   
952.
Personal identification based on radiographic vertebral features   总被引:4,自引:0,他引:4  
Personal identification of human remains constitutes about 10% of the normal caseload of any forensic medicine practice. Identification can be achieved by a variety of methods, one of which is the comparison of antemortem and postmortem radiographs. There are numerous accounts of cranial and dental radiographic features useful for identification, whereas the availability of postcranial radiographs and especially plates that depict the vertebral column is less widespread among the forensic community. The authors here review the various vertebral features instrumental in positive identification that can be identified on radiographs of the spine.  相似文献   
953.
954.
Death resulting from ruptured cerebral artery aneurysm: 219 cases   总被引:1,自引:0,他引:1  
To characterize the demographics of ruptured cerebral artery aneurysm as a cause of death and to examine the effect of improved diagnostic and therapeutic techniques on the incidence of sudden death associated with the condition, the authors reviewed 219 autopsies performed at the Dallas County Medical Examiner's Office between 1977 and 1997 in which the cause of death was ruptured cerebral artery aneurysm. Ruptured cerebral artery aneurysms accounted for 1.5% of 15,033 natural deaths and 0.4% of all deaths (45,492) followed by autopsy during this period. The majority (56%) of cases occurred in females, with Caucasian females composing the largest group (38%). Seventy-seven percent of cases occurred in individuals between the ages of 31 and 70 years, with the highest concentration in the 41- to 50-year decade (29%). The most common location for ruptured aneurysms was the middle cerebral artery distribution (39%). Multiple aneurysms occurred in 22 (9.1%) cases. Other factors, such as medical history, coexisting disease, symptoms, activity at onset of symptoms, survival time, and toxicology results are also presented. Compared with literature reports before 1980, when ruptured cerebral artery aneurysms were reported as the cause of death in approximately 4% to 5% of sudden natural deaths, the results of this study suggest that despite improved diagnostic and therapeutic techniques during the past two decades, morbidity and mortality from ruptured aneurysms remain a significant health problem.  相似文献   
955.
Since 1958 NASA has invested approximately $3.7 billion in life sciences R&D in the support of the successful human space flight program. There are numerous studies documenting the spin-off technologies that can be traced to NASA research and development activities. Most of these studies describe the technologies and their uses; however only a few measure the economic impact of the spin-offs and most of these are benefit/cost studies that tend to overstate benefits or underestimate costs. This study takes a different approach, measuring only economic impacts to the companies that developed successful spin-off products from NASA life sciences investments. A personal interview was conducted with each company and the benefits are conservatively estimated as the value-added by the NASA technology to the company's output and the amount of additional private R&D stimulated by the NASA R&D.This pilot study of fifteen companies, using a very conservative measurement technique, found a large return to companies that have successfully commercialized NASA life sciences spin-off products. Value-added benefits totaled over $3.7 billion in life sciences R&D in the support of the successful human space flight program. There are numerous studies documenting the spin-off technologies that can be traced to NASA research and development activities. Most of these studies describe the technologies and their uses; however only a few measure the economic impact of the spin-offs and most of these are benefit/cost studies that tend to overstate benefits or underestimate costs. This study takes a different approach, measuring only economic impacts to the companies that developed successful spin-off products from NASA life sciences investments. A personal interview was conducted with each company and the benefits are conservatively estimated as the value-added by the NASA technology to the company's output and the amount of additional private R&D stimulated by the NASA R&D.This pilot study of fifteen companies, using a very conservative measurement technique, found a large return to companies that have successfully commercialized NASA life sciences spin-off products. Value-added benefits totaled over 1.5 billion and a NASA R&D total investment in these 15 technologies of 64 million was found to stimulate an additional64 million was found to stimulate an additional 200 million in private R&D.  相似文献   
956.
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   
957.
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   
958.
959.
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   
960.
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