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Anterior cruciate ligament (ACL) reconstruction was performed in a single hind limb of 30 sheep using a doubled semitendinosus tendon graft. Three additional animals were used as controls. Histologic and biomechanical analysis was performed from 4-52 weeks postoperatively. Perpendicular collagen fibers were found connecting the tendon graft to the bone tunnels at 8 weeks. These fibers were seen circumferentially at 12 weeks. By 24 weeks, the bone tunnel was well-defined, and no further changes were observed at 52 weeks. Tendon incorporation within the femoral and tibial tunnels was similar at each interval. Although the small sample size did not permit statistical testing, the reconstruction strength was similar up to 12 weeks (15%-19% of controls). This increased at 24 (28%) and 52 (40%) weeks. The stiffness primarily increased from 4-8 weeks (18%-39%) and 24-52 weeks (52%-82%). Up to 12 weeks, failures occurred by graft pull-out from the bone tunnel. All 24- and 52-week specimens ruptured through the intra-articular portion of the graft, further indicating sufficient graft incorporation within the bone tunnels.  相似文献   
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Objective. To review imaging studies of isolated involvement of the sacrum due to tuberculosis and determine the role of imaging in the diagnosis and management of these patients. Design and patients. A retrospective analysis of 15 cases of isolated sacral tuberculosis imaged with MR imaging was performed. The CT images were also reviewed where available, and the various lesion characteristics were identified. We also reviewed the medical records in an attempt to determine the impact of the imaging studies on the management of these patients. Results. Fifteen patients (5 male, 10 female) presented with symptoms of 3–15 months’ duration. Chronic localized backache with muscle spasm was the commonest presenting symptom; discharging sinuses with abscess formation was found in six patients, five of whom were children. MR imaging of the sacrum revealed a hypointense marrow signal on T1-weighted images and hyperintense signal on T2-weighted images in 14 of 15 patients, the S2 vertebra being always involved. CT revealed osteolytic changes in the sacrum in all the five patients in whom CT was performed. All patients showed marked clinical improvement within 1 year of anti-tuberculous chemotherapy. Conclusion. Isolated tuberculosis of the sacrum is uncommon but should be suspected in patients presenting with chronic low backache or children with discharging sinuses/abscesses and showing sacral destruction on CT or MR imaging. MR imaging can identify cases and enables early institution of anti- tuberculous chemotherapy. Received: 31 August 1999 Revision requested: 1 November 1999 Revision received: 27 March 2000 Accepted: 14 April 2000  相似文献   
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Gamma Surgery for Hemangiopericytomas   总被引:6,自引:0,他引:6  
A retrospective analysis of a consecutive series of 12 patients with 15 intracranial hemangiopericytomas treated at the University of Virginia using Gamma surgery is presented. Clinical and radiographic follow up of 3 to 56 months is available for 10 patients with 12 tumors. There was one tumor present at the time of initial Gamma surgery in each patient. Two new tumors occurred in patients previously treated. Nine of the tumors decreased in volume and three remained stable. Four of the nine tumors that shrank later progressed at an average of 22 months after treatment. Of the tumors that decreased in volume and have not progressed, the response has been for an average of 11 months. The follow-up for two tumors that remained unchanged was 10 and 34 months (average 22 months). A third tumor was unchanged at 42 months but the patient died of new disease adjacent to the treated area in the anterior skull base. There were no complications and the quality of life following the procedure was maintained or improved in every case. Gamma surgery is effective in palliating the patients by decreasing tumor volume and delaying recurrence.  相似文献   
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Wound complications following operative fixation of calcaneal fractures   总被引:36,自引:0,他引:36  
Al-Mudhaffar M  Prasad CV  Mofidi A 《Injury》2000,31(6):461-464
The aim of our study was to find the incidence of wound complications following operative fixation of fractured calcanea and identify the risk factors contributing to them. We retrospectively reviewed the results of operative treatment of 33 calcaneal fractures in 30 patients over a 4-year period. We report an overall wound complication rate of 18.1%. Wound infection, haematoma, dehiscence and heel necrosis were noted in our series with or without underlying osteomyelitis. We identified the following as risk factors to the causation of post-operative wound complications: (a) fall of more than 3.4 m (p<0.005); (b) surgery within 7 days (p<0.05); (c) operating time in excess of 2 h (p<0.05); (d) tourniquet time in excess of 1.5 h (p<0.001). We recommend careful attention to these factors in treating calcaneal fractures.  相似文献   
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INTRODUCTION: Promoting appropriate use of drugs is an essential element in achieving quality of health and medical cares for patients and the community, and also to minimize financial burden. OBJECTIVE: The objective of this paper is to assess the successful intervention for sustainability and effects in post research phase. To address these problems, a variety of educational, managerial and regulatory strategies to improve prescribing have been tried in Nepal. When training is combined with a managerial intervention i.e. peer-group discussion, it results into improved changes in prescribing practices of paramedics in several practices. METHODOLOGY: A prospective, three-way design study consisting of small group training, small group training followed by peer-group discussion and control was conducted in three regions of Nepal including one hill and two terai (plains) districts from each region. The study included all health post from the sampled districts, making 80 health posts the study population. RESULTS: The study revealed the effectiveness of the peer-group discussion approach in improving the prescribing practices. An assessment to identify the sustainability of the strategy and its effect within the district healthcare system after the completion of the research phase was undertaken. The study found that peer-group discussion was discontinued in all targeted districts and the improved practices were not sustained after the completion of the research. Various reasons have been found for not continuing the effective intervention.  相似文献   
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