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251.
Spontaneous pneumomediastinum commonly occurs in healthy young men or parturient women in whom an increased intra-alveolar pressure (Valsalva maneuver, asthma, cough, emesis) leads to the rupture of the marginal pulmonary alveoli. The air ascends along the bronchi to the mediastinum and the subcutaneous space of the neck, causing cervico-fascial subcutaneous emphysema in 70-90% of cases. Ninety-five forensic cases, including five cases of hanging, were examined using postmortem multi-slice computed tomography (MSCT) and magnetic resonance imaging (MRI) prior to autopsy until December 2003. This paper describes the findings of pneumomediastinum and cervical emphysema in three of five cases of hanging. The mechanism of its formation is discussed based on these results and a review of the literature. In conclusion, when putrefaction gas can be excluded the findings of pneumomediastinum and cervical soft tissue emphysema serve as evidence of vitality of a hanged person. Postmortem cross-sectional imaging is considered a useful visualization tool for emphysema, with a great potential for examination and documentation.  相似文献   
252.
Steamer accidents, through contact with the bucket wheel, are very seldom today. No publication of such a kind of fatal accident could be found in literature. We present the case of a fatal steamer accident, in which the findings of a blunt traumatization of a person by the ship was completely documented by post-mortem combined multi-slice computed tomography (MSCT) and magnetic resonance imaging (MRI) examinations. A rupture of the aorta was detected using both radiological methods without use of radiopaque material. Radiological examination revealed a comminuted fracture of the thorax vertebrae at the same level as the aortic rupture. Injuries of the soft tissues of the back, caused by the bucket wheel of the steamer, were also diagnosed. In addition to the signs of blunt force trauma the findings of drowning such as an over inflation of the lungs, fluid in the stomach and duodenum were revealed. Furthermore, algological analysis detected diatoms in the lung tissue and blood from the left heart. Therefore, the cause of death was considered being a combination of fatal hemorrhage, caused by the aortic rupture, and drowning. We conclude that virtual autopsy using combined post-mortem MSCT and MRI is a useful tool for documentation, visualisation and analysis of the findings of blunt force trauma and drowning with a large potential in forensic medicine.  相似文献   
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Prevention science has produced information about risk and protective factors that predict adolescent drug use and related problem behaviors. This paper investigates the Communities That Care Youth Survey that measures multiple risk and protective factors. Using a sample of 172,628 students who participated in surveys administered in seven states in 1998, analyses were conducted to test the factor structure of these risk and protective factors and to test the equivalence of the factor models across five racial/ethnic groups (African Americans, Asians or Pacific Islanders, Caucasians, Hispanic Americans, and Native Americans), four grade levels (6th, 8th, 10th, and 12th) and both gender groups. Results support the construct validity of the surveys risk and protective factor scales and indicate that the measures are equally reliable across males and females and five racial/ethnic groups. Implications of these findings for science-based prevention planning are discussed.  相似文献   
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Telephone conference calls could be used to extend participation in public decision-making. In order to clarify the involved problems and prospects we conducted 16 nine-member conference calls discussing and voting on a public issue. The discussions were recorded for analysis and a questionnaire was administered. The meetings worked well despite the isolation of the participants and the lack of visual contact. Access to the floor was easy, attention good, and participation was eager. The participants felt that the analysis of the topic had been effective. The chairman's guidance of the discussion was judged effective, and his actions legitimate. Additionally, the data suggest what we might call greater intellectual elbow room—less pressure to go along with the group opinion than in face-to-face meetings, and more ease in changing opinions and positions. The disagreements about the issue did not spill over into emotional hostility. The participants were quite pleased with the conduct and efficacy of the electronic meetings. These findings suggest that a mass participatory system, based upon such electronic meetings, can also be used to provide wider involvement in decision-making in our society.This study is part of a much larger project exploring the use of technology to extend political participation. The project is supported by the National Science Foundation, grant # GI-29940. Dr. Amitai Etzioni and Dr. Stephen Unger are Co-Principal Investigators for the MINERVA Project, which is being carried out at the Center for Policy Research in New York. The author is particularly indebted to Dr. Etzioni for many important contributions to the conception, design and analysis of the study reported in this paper. Dr. Unger also made significant contributions to the development of the study. Camille Gubello, Joshua Freeman and Nancy Gershon were of central importance in conducting the experiments, assembling the data and preparing this report.  相似文献   
256.
The author surveys and compares the legal professions of 15 nations, including both civil law and common law countries. The essay is organized around the ways that legal professionals control their markets—first by controlling "production of producers" or who and how many enter the profession (with formal education or apprenticeship requirements, examinations, access to entry-level positions). Legal professionals also control "production by producers"—both external competitors and lawyers themselves. This occurs, for example, through definition and defense of the professional monopoly, control of competition between licensed professionals, and creation of demand. The discussion takes place against the background of the legal profession's recent history—assessing changes in its composition (by race, age, gender), in lawyers' practice settings, in the categories of work they perform, and in the income and status associated with these categories and with the profession in general.  相似文献   
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The medical indemnity crisis in Australia forced doctors, lawyers and insurers to re-appraise the way they handle claims for compensation for medical error. This article examines some of the new approaches available in Australia when patients claim compensation from their doctors.  相似文献   
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