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Patrick N Smith Jeffrey R Balzer Mustafa H Khan Rick A Davis Donald Crammond William C Welch Peter Gerszten Robert J Sclabassi James D Kang William F Donaldson 《The spine journal》2007,7(1):83-87
BACKGROUND CONTEXT: Intraoperative somatosensory evoked potential (SSEP) monitoring has been shown to reduce the incidence of new postoperative neurological deficits in scoliosis surgery. However, its usefulness during cervical spine surgery remains a subject of debate. PURPOSE: To determine the utility of intraoperative SSEP monitoring in a specific patient population (those with cervical radiculopathy in the absence of myelopathy) who underwent anterior cervical discectomy and fusion (ACDF) surgery. STUDY DESIGN: Retrospective review. PATIENT SAMPLE: A total of 1,039 nonmyelopathic patients who underwent single or multilevel ACDF surgery. The control group (462 patients) did not have intraoperative SSEP monitoring, whereas the monitored group (577 patients) had continuous intraoperative SSEP monitoring performed. OUTCOME MEASURE: A new postoperative neurological deficit. METHODS: SSEP tracings were reviewed for all 577 patients in the monitored group and all significant signal changes were noted. Medical records were reviewed for all 1,039 patients to determine if any new neurological deficits developed in the immediate postoperative period. RESULTS: None of the patients in the control group had any new postoperative neurological deficits. In the monitored group there were six instances of transient SSEP changes (1 due to suspected carotid artery compression; 5 thought to be due to transient hypotension) which resolved with the appropriate intraoperative intervention (repositioning of retractors; raising the arterial blood pressure). Upon waking up from anesthesia, one patient in the monitored group had a new neurological deficit (partial central cord syndrome) despite normal intraoperative SSEP signals. CONCLUSIONS: ACDF appears to be a safe surgical procedure with a low incidence of iatrogenic neurological injury. Transient SSEP signal changes, which improved with intraoperative interventions, were not associated with new postoperative neurological deficits. An intraoperative neurological deficit is possible despite normal SSEP signals. 相似文献
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G. N. Smith Jr E. A. Mickler K. K. Payne J. Lee M. Duncan J. Reynolds B. Foresman D. S. Wilkes 《American journal of transplantation》2007,7(7):1856-1861
Parenchymal disease in the allograft lung is associated with interstitial remodeling believed to be mediated by matrix metalloproteinases (MMPs). Recent studies suggest high levels of MMP-9 are associated with bronchiolitis obliterans syndrome (BOS) in lung transplant recipients. Since BOS occurs late in the posttransplant period and may be preceded by episodes of acute rejection or infection, which are associated with interstitial remodeling, we examined MMP profiles in allograft bronchoalveolar lavage (BAL) fluid in the early posttransplant period (preceding BOS). Gelatin zymography, protein array analysis and specific ELISA on BAL fluids from transplanted lungs indicated that MMP-8, MMP-9 and TIMP-1 were strongly expressed in allograft BAL fluid from stable patients, or those with infection or rejection compared to BAL fluid from normal volunteers. Elevated expression of MMP-8, MMP-9 and TIMP-1 occurred early, and was sustained for the 3.2 years covered in this study. Elevations of MMP-8, MMP-9 and TIMP-1 in the first 2 years posttransplant appear to be associated with lung transplantation itself, and not infection or rejection. These data suggest that ongoing and clinically silent MMP activity could perpetuate progressive disease in the allograft lung. 相似文献
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Paul Roderick Ruth Davies Chris Jones Terry Feest Steve Smith Ken Farrington 《Nephrology, dialysis, transplantation》2004,19(3):692-701
BACKGROUND: The demand for renal replacement therapy (RRT) in England has risen steadily, although from a lower base than many other developed countries. Predicting the future demand for RRT and the impact of factors such as the acceptance rate, transplant supply and patient survival, is required in order to inform the planning of such services. METHODS: A discrete event simulation model estimates the future demand for RRT in England in 2010 for a range of scenarios. The model uses current prevalence and current and projected future acceptance rates, survival rates and the transitions between modalities to predict future patient numbers. National population and mortality data, published literature and data from the UK Renal Registry and UK Transplant, are used to estimate unmet need for RRT, the impact of changing demography and incidence of Type 2 diabetes, patient haemodialysis (HD) survival and transplant supply. RESULTS: By 2010 the predicted prevalence will have increased from about 30,000 in 2000 to between 42 and 51,000 (900-1000 p.m.p.), an average annual growth of 4.5-6%. Changing transplant supply has a small effect on overall numbers but changes the proportion of patients with functioning graft by up to 8%. Even with an optimistic increase in transplant supply (11% p.a. for 5 years), numbers on HD will continue to rise substantially, especially in the elderly. The factors most influencing future patient numbers are the acceptance rate and dialysis survival. CONCLUSION: This model predicts a substantial growth in the RRT population to 2010 to a rate approaching 1000 p.m.p., particularly in the elderly and those on HD, with a steady state not being reached for at least 25 years. 相似文献
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J B Alexis R J Poppiti E Turbat-Herrera M D Smith 《The American Journal of dermatopathology》1991,13(2):189-194
A case of congenital self-healing reticulohistiocytosis in an otherwise healthy newborn boy is presented. Histological, immunohistochemical, and ultrastructural findings are described and the nosologic position of this entity is discussed. 相似文献
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Passenger seating position and the risk of passenger death in traffic crashes: a matched cohort study 总被引:11,自引:0,他引:11 下载免费PDF全文
OBJECTIVE: To estimate the association of passenger seating position with the risk of death for passengers in traffic crashes. Design, setting, PARTICIPANTS: Matched cohort analysis of data from the National Highway Traffic Safety Administration Fatality Analysis Reporting System regarding 56 644 passengers in 23 308 passenger cars, light trucks, vans, and sport utility vehicles that crashed during 1990-2001. MAIN OUTCOME MEASURE: The adjusted risk ratio (aRR) for death of a rear seat passenger compared with a front seat passenger within 30 days of a crash. RESULTS: The aRR for all passengers in the rear seat in a crash was 0.79 (95% CI 0.77 to 0.82). This estimate varied by age, restraint use, and the presence of a front passenger airbag (p<0.001). For restrained passengers in cars with a front passenger airbag, the aRR was 0.62 (95% CI 0.48 to 0.81) for children 0-12 years, 0.96 (95% CI 0.88 to 1.06) for passengers 13-29 years, 1.03 (95% CI 0.93 to 1.15) for passengers 30-59 years, and 1.06 (95% CI 0.90 to 1.26) for passengers 60 years or older. The rear seat was associated with more protection in cars without front airbags and more protection for unrestrained passengers compared with restrained passengers. CONCLUSIONS: Previous studies have reported that the rear seat was safer for persons of all ages; thus seating a young child in the rear has often meant that older children and adults had to assume an increased risk of death by sitting in the front. These results suggest that when front passenger airbags are present and passengers are restrained, putting adults in front and children in back enhances child safety without sacrificing adult safety. 相似文献