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901.
Tubulointerstitial fibrosis (TIF) is a hallmark of chronic kidney disease resulting from diverse etiologies and predicts severity and progression of the kidney disease. To investigate the pathogenesis of TIF, complete unilateral ureteral obstruction (UUO) is the most widely used animal model. However, UUO precludes evaluation of renal function. In the present study, we created a rat model of chronic partial ureteral obstruction (PUO), which allowed assessment of renal function at different intervals after obstruction. We examined the effects of pentoxifylline (PTF), a phosphodiesterase inhibitor used clinically to treat peripheral artery disease, on renal function and TIF. Studies were performed in sham-PUO rats and rats with 14-day PUO or 30-day PUO receiving vehicle in drinking water or PTF (400?mg/liter in drinking water). At day-14 PUO, glomerular filtration rate (GFR) was markedly and similarly depressed in rats receiving vehicle or PTF as compared with sham-operated rats. However, at day-30 PUO, GFR in rats receiving PTF was significantly higher than that in rats receiving vehicle, approaching the level seen in the sham-operated rats. At day-30 PUO, histologic studies also revealed a marked reduction of TIF in rats treated with PTF as compared with the rats receiving vehicle in drinking water. Western blot analysis demonstrated that at day-30 the expression of α-smooth muscle actin (an indicator of renal fibrosis) in the medulla was significantly reduced in PUO rats treated with PTF. In conclusion, PTF treatment ameliorated renal fibrosis and helped preserve renal function in a rodent model of PUO. 相似文献
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Kristen H. Fernandez M.D. Peter Rady M.D. Ph.D. Steven Tyring M.D. Ph.D. M.B.A. Mary S. Stone M.D. 《Pediatric dermatology》2014,31(3):400-402
Abstract: A 4‐year‐old girl with an established diagnosis of atopic dermatitis, previously severe and treated with cyclosporine, developed widespread papules that demonstrated changes consistent with epidermodysplasia verruciformis on biopsy. Human papilloma virus (HPV) typing was performed and was consistent with epidermodysplasia verruciformis‐type HPV (type 5). These lesions rapidly resolved with a 2‐week course of imiquimod. Rapid resolution and no family history of epidermodysplasia verruciformis make this most consistent with acquired epidermodysplasia verruciformis. This case is the first reported case of acquired epidermodysplasia verruciformis in a child without the human immunodeficiency virus and may be linked to cyclosporine use, which also has never been previously reported. 相似文献
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Hollis Day MD MS Elizabeth Eckstrom MD MPH Sei Lee MD MCR Heidi Wald MD MPH Steven Counsell MD Eugene Rich MD 《Journal of general internal medicine》2014,29(6):911-914
As the population ages, the quantity and complexity of comorbidities only increases in the primary care setting. Health systems strive to improve quality of care and enhance cost savings, but current administrative and payment systems do not easily support the implementation of existing evidence and best practices for multimorbid adults in most primary care offices. This perspectives piece sets forth a research agenda in the area of implementation science at the intersection of geriatrics and general internal medicine. We challenge academic medical centers, medical societies, journals, and funders to actively value and support investigation in this area as much as traditional research pathways. 相似文献
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Phaedra S. Corso Justin B. Ingels Steven M. Kogan E. Michael Foster Yi-Fu Chen Gene H. Brody 《Prevention science》2013,14(5):447-456
Programmatic cost analyses of preventive interventions commonly have a number of methodological difficulties. To determine the mean total costs and properly characterize variability, one often has to deal with small sample sizes, skewed distributions, and especially missing data. Standard approaches for dealing with missing data such as multiple imputation may suffer from a small sample size, a lack of appropriate covariates, or too few details around the method used to handle the missing data. In this study, we estimate total programmatic costs for a prevention trial evaluating the Strong African American Families-Teen program. This intervention focuses on the prevention of substance abuse and risky sexual behavior. To account for missing data in the assessment of programmatic costs we compare multiple imputation to probabilistic sensitivity analysis. The latter approach uses collected cost data to create a distribution around each input parameter. We found that with the multiple imputation approach, the mean (95 % confidence interval) incremental difference was $2,149 ($397, $3,901). With the probabilistic sensitivity analysis approach, the incremental difference was $2,583 ($778, $4,346). Although the true cost of the program is unknown, probabilistic sensitivity analysis may be a more viable alternative for capturing variability in estimates of programmatic costs when dealing with missing data, particularly with small sample sizes and the lack of strong predictor variables. Further, the larger standard errors produced by the probabilistic sensitivity analysis method may signal its ability to capture more of the variability in the data, thus better informing policymakers on the potentially true cost of the intervention. 相似文献
909.
Steven P. Van Camp 《The Physician and sportsmedicine》2013,41(9):153-157
Opponents of long-distance running have used the death of Jim Fixx as an l-told-you-so. But Fixx's death was not so much a matter of a neurotic attachment to running as it was his refusal to submit himself to periodic medical evaluations. 相似文献
910.
Steven P. Roy 《The Physician and sportsmedicine》2013,41(11):83-94
Time loss from participation is often used to define injury, but one physician uses different criteria in evaluating wrestlers. 相似文献