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71.
This study evaluated factors influencing fracture (n = 197) and osteotomy (n = 200) healing in children with moderate to severe OI. Pamidronate treatment was associated with delayed healing after osteotomy, but not after fracture. The data suggest that both pamidronate and mechanical factors influence bone healing in this cohort. INTRODUCTION: Intravenous pamidronate is widely used to treat children with moderate to severe osteogenesis imperfecta (OI). However, the effect of this treatment on bone healing is not well characterized. We therefore retrospectively analyzed the healing of lower limb fractures and osteotomies in children with moderate to severe OI, both before and after the start of pamidronate treatment. MATERIALS AND METHODS: Bone healing was evaluated on standard radiographs after 197 lower limb fractures (132 femur and 65 tibia) in 82 patients (age at fracture, 0.0-19.9 years) and 200 intramedullary rodding procedures in 79 patients (age at surgery, 1.2-19.8 years). Delayed healing was diagnosed when a fracture or osteotomy line was at least partially visible 12 months after the event. RESULTS: Delayed fracture healing was observed more frequently during than before pamidronate treatment. However, the effect of pamidronate was no longer significant when age differences were taken into account (odds ratio [OR], 1.76; 95% CI, 0.61-5.10). Better mobility status was a strong independent predictor of delayed healing after fractures that occurred during pamidronate treatment. After osteotomies, delayed healing was more frequent when pamidronate had been started before surgery (OR, 7.29; 95% CI, 2.62-20.3), and this effect persisted after adjustment for multiple confounders. During pamidronate treatment, older age (OR per year of age, 1.25; 95% CI, 1.06-1.47) and osteotomy of the tibia (OR, 3.51; 95% CI, 1.57-7.82) were independent predictors of delayed healing. CONCLUSIONS: This study suggests that pamidronate therapy is associated with delayed healing of osteotomy sites after intramedullary rodding procedures. Better mobility status, but not pamidronate treatment, seems to be predictive of delayed healing after fractures.  相似文献   
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OBJECTIVE: To develop biomechanical variable models for driver skull base injury mechanisms in motor vehicle collisions. STUDY DESIGN: Retrospective database review. METHODS: Biomechanical collision variables and safety restraint data were analyzed for Crash Injury Research and Engineering Network skull base trauma subjects enrolled during the recruitment period between 1996 and 2005. RESULTS: For drivers satisfying inclusion criteria (n = 26), injury resulted from contact with rigid vehicle structural elements in 82%, and occurred in 50% despite both seatbelt and air bags. Eight percent used neither seatbelts nor air bags. Seventy-two percent involved vector velocity changes greater than 30 mph. The relative morbidity of skull base injuries was also detailed. CONCLUSION: The majority of driver skull base injuries resulted from contact with rigid vehicle structural elements in high velocity crashes. Seatbelt and air bag use could not be definitively correlated with skull base injury. CLINICAL SIGNIFICANCE: Injury mechanism models can be developed that facilitate further investigations to determine impact and scope on a national scale.  相似文献   
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Transplant atherosclerotic coronary disease remains the leading cause of death in heart transplant recipients. We report the first case of coronary stent implantation in a heart graft for epicardial focal stenosis. Due to the lower rate of restenosis after stenting in the native coronary artery, we suggest that coronary stenting be considered an acceptable, first intention therapeutic option instead of angioplasty alone whenever possible.  相似文献   
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Nephritis occurs in 20%–50% of children with Henoch-Schönlein purpura (HSP), and the onset of renal involvement may be delayed for weeks or months in a substantial proportion of patients. The present study was performed to determine whether corticosteroid therapy was effective in preventing delayed nephritis in children with HSP. The medical records of 69 children with HSP were reviewed. Nineteen patients had acute nephritis occurring from 1–12 days after the onset of other signs and symptoms. The remaining 50 patients had no evidence of acute renal involvement. Of these 50 patients, 20 were treated during the acute phase of the illness with corticosteroids, while 30 never received corticosteroid therapy. Delayed nephritis (>3 weeks following an initial normal urinalysis) occurred in 4 of 20 (20%) patients who received prior corticosteroid treatment, and in 6 of 30 (20%) patients who were not treated. These results indicate that early corticosteroid therapy does not prevent delayed nephritis in children with HSP.  相似文献   
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Using a simplified procedure, we have extracted DNA from unstained paraffin sections of needle biopsies of kidney and liver transplants and identified the presence of CMV using the polymerase chain reaction. This method utilizes oligonucleotide primers for two genes shown to be specific for cytomegalovirus (CMV) as well as an internal control gene (hemoglobin) in a single reaction. Utilizing nested PCR amplification with agarose gel electrophoresis, CMV can be detected without radioisotopes to a level of sensitivity equivalent to one one-hundredth of a cytomegalic virocyte per cm2 of a 3-microM paraffin section. This method is applicable to situations where only scarce paraffin-embedded tissue is available.  相似文献   
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