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11.
The purpose of this study was to assess 7 methods of fixation for a midtarsal osteotomy. Polyurethane foam models (N = 6) and cadaver specimens (N = 4-7) were used to examine the force generated by the different constructs of fixation. A midtarsal osteotomy was performed on each specimen in the test groups. The osteotomies were fixated either with 2 parallel 0.062-in Kirschner wires and 40-mm-long, 4-mm partially threaded, cancellous, cannulated titanium screws, an external ring fixator (frame), a frame with wires tensioned (tension), a frame with wires tensioned and compressed toward the osteotomy (tension and compression), a frame with tension, compression, and parallel Kirschner wires, or a frame with tension, compression, and two 4.0 cannulated parallel screws, respectively. Each model was fixated, and the force generated by the construct across the osteotomy was recorded via the use of pressure-sensitive film. Statistical analysis of the data in the polyurethane foam group determined that the use of frame with tension, compression, and two 4.0 parallel cannulated screws was statistically superior to 1) frame, 2) frame with tension, 3) 2 parallel Kirschner wires, 4) two 4.0 cannulated parallel screws, and 5) frame with tension and compression. A cadaver study determined that the frame with tension, compression, and 2 parallel Kirschner wires was statistically superior to 1) frame and 2) two parallel Kirschner wires. These findings suggest that there is a difference in the force generated by the type of fixation construct across a midtarsal osteotomy.  相似文献   
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We have used 29Si solid-state nuclear magnetic resonance (NMR) spectroscopy to study the chemical structure of the silicone gels in virgin and explanted breast prostheses. Despite evidences of alteration in the morphological appearance of the silicone gel inside the breast prosthesis, our results do not reveal changes in the chemical nature and structure of the silicone gels after implantation. In addition to the main 29Si resonance peak at ?22.26 ppm that corresponds to the resonance frequency of the D repeat unit of the polysiloxane chains, the high sensitivity of our NMR technique allows the detection of very low concentrations of silicone compounds. Within our experimental detection limit of 0.2%, no signal between ?90 ppm and ?150 ppm are observed. This indicates that no silica products are present inside the gel of the prostheses. Furthermore, our 29Si NMR spectra indicate differences in the chemical compositions of the silicone gels from different manufacturers.  相似文献   
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Spontaneous hemothorax is a rare and life threatening complication of neurofibromatosis. Two types of vascular involvement have been described: (a) stenotic or aneurysmal alterations in large vessels such as the aorta and its branches; and (b) dysplastic features in smaller vessels. Thoracotomy and surgical ligation of the bleeding vessels is primarily indicated in the presence of active bleeding with associated hemodynamic compromise. A more conservative approach with endovascular embolization or non-operative management have also been reported in case of hemodynamic stability. We present a rare case of spontaneous hemothorax treated conservatively in a patient with von Recklinghausen's disease.  相似文献   
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The health of a team participating in the 1990 World Solar Car Challenge was recorded for 10 of the 11 race days. Morbidity was collected during daily consultations with the team doctor and the diagnoses were later converted to the ICPC code. Team members' self-perceived health status was also recorded daily, using the Nottingham Health Profile. Team drivers consulted the doctor more often than the support staff and the three full-time drivers had significantly more diagnoses than the support staff. The Nottingham Health Profile scores on sleep, energy and emotional reactions showed correlations between higher minimum temperatures and sleep for all team members and for the three full-time drivers, there were significant correlations between increasing maximum temperatures and emotional reaction scores. The morbidity records and perceived health scores reflect the conditions of the race. Twenty-five per cent of full-time driver consultations dealt with skin, eyelid or finger infections probably caused by the lack of washing water. The scores on sleep and emotional reactions were affected by temperature and previous research reports degradation in concentration and dual tasks with increasing temperature. This may account for the difficulty some drivers had in continuing their shifts. Close supervision of the drivers and the recording of their perceived health status helped reduce the health problems of the team.  相似文献   
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Binge drinking: prevalence, patterns and policy   总被引:4,自引:0,他引:4  
This paper presents analyses of the pattern of ‘bingedrinking’ in Wales, based on data drawn from a 1993 surveyof 12 167 (67%) 18–64 year olds resident in 15 212 householdsin Wales. Binge drinking, defined as drinking half the weeklyrecommended units of alcohol in a single drinking session, wasfound to be most prevalent among young adults, males, the manualsocial group, those who did not undertake any further educationafter secondary school, those who are single, divorced or separated,beer drinkers and those who concentrate most of their drinkingat weekends. 28.2% of men and 8.2% of women reported binge drinkingat least once a week, of whom about 42% felt that their levelof drinking was harmful to their health. About a quarter statedthat they would like to reduce their alcohol consumption butonly a small number had been advised to do so by their GeneralPractitioner. The public health impact of binge drinking isdiscussed. It is recommended that sensible drinking messagesshould emphasize the need to reduce binge drinking as well asto moderate overall weekly consumption and should be supportedby policies to create environments that support sensible alcoholuse.  相似文献   
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