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We report the second case of cutaneous myelofibrosis with a documented JAK2 activating mutation involving the scalp of a 67‐year‐old woman with primary myelofibrosis in her marrow. In contrast to the previous case, the biopsy revealed extensive lesional collagen deposition and closely mimicked a fibrohistiocytic proliferation. Similar rare lesions occurring in the setting of myeloproliferative neoplasms have been called sclerosing extramedullary hematopoietic tumors. These entities appear histomorphologically and etiologically distinct from extramedullary hematopoiesis, and their diagnosis should prompt the workup for a myeloproliferative neoplasm in the absence of an antecedent diagnosis. The presence of the JAK2 mutation in our case confirmed that the lesions represented skin involvement by a neoplastic myeloid proliferation and not compensatory extramedullary hematopoiesis. Our patient died of disease several months following the appearance of her lesions, which is in keeping with other reports that suggest that cutaneous myelofibrosis may serve as an independent poor prognostic sign in otherwise advanced primary myelofibrosis. A review of the literature further emphasizes the importance of distinguishing this entity from mesenchymal neoplasms and acute myeloid leukemia involving the skin.  相似文献   
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Aims of treatment for Crohn disease have moved beyond the resolution of clinical symptoms to objective end points including endoscopic and radiological normality. Regular re-evaluation of disease status to safely, readily and reliably detect the presence of inflammation and complications is paramount. Improvements in sonographic technology over recent years have facilitated a growing enthusiasm among radiologists and gastroenterologists in the use of ultrasound for the assessment of inflammatory bowel disease. Transabdominal intestinal ultrasound is accurate, affordable and safe for the assessment of lumi-nal inflammation and complications in Crohn disease, and can be performed with or without the use of intravenous contrast enhancement. Perianal fistulizing disease is a common, complex and often treatment-refractory complication of Crohn disease, which requires regular radiological monitoring. Endoanal ultrasound is invasive, uncomfortable and yields limited assessment of the perineal region. Although magnetic resonance imaging of the pelvis is established, timely access may be a problem. Transperineal ultrasound has been described in small studies, and is an accurate, painless and cost-effective method for documenting perianal fluid collections, fistulas and sinus tracts. In the present article, the authors review the literature regarding perineal ultrasound for the assessment of perianal Crohn disease and use case examples to illustrate its clinical utility.  相似文献   
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IntroductionThe Royal College of Surgeons of England (RCS) has issued guidance regarding the use of reoperation rates in the revalidation of UK-based orthopaedic surgeons. Currently, little has been published concerning acceptable rates of reoperation following primary surgical management of orthopaedic trauma, particularly with reference to revalidation.MethodsA retrospective review was conducted of patients undergoing clearly defined reoperations following primary surgical management of trauma between 1 January 2010 and 31 December 2011. A full case note review was undertaken to establish the demographics, clinical course and context of reoperation. A review of the imaging was performed to establish whether the procedure performed was in line with accepted trauma practice and whether the technical execution was acceptable.ResultsA total of 3,688 patients underwent primary procedures within the time period studied while 70 (1.90%, 99% CI: 1.39–2.55) required an unplanned reoperation. Thirty-nine (56%) of these patients were male. The mean age of patients was 56 years (range: 18–98 years) and there was a median time to reoperation of 50 days (IQR: 13–154 days). Potentially avoidable reoperations occurred in 41 patients (58.6%, 99% CI: 43.2–72.6). This was largely due to technical errors (40 patients, 57.1%, 99% CI: 41.8–71.3), representing 1.11% (99% CI: 0.73–1.64) of the total trauma workload. Within RCS guidelines, 28-day reoperation rates for hip, wrist and ankle fractures were 1.4% (99% CI: 0.5–3.3), 3.5% (99% CI: 0.8%–12.1) and 1.86% (99% CI: 0.4–6.6) respectively.ConclusionsWe present novel work that has established baseline reoperation rates for index procedures required for revalidation of orthopaedic surgeons.  相似文献   
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The present study examined the influence of maternal and child characteristics on parenting behaviors in a genetically informative study. The participants were 976 twins and their mothers from the Colorado Longitudinal Twin Study and the Twin Infant Project. Indicators of positive parenting were coded during parent–child interactions when twins were 7–36 months old. Child cognitive abilities and affection were independent correlates of positive parenting. There were significant gender differences in the magnitude of genetic and environmental influences on positive parenting, with shared environmental influences on parenting of girls and additive genetic influences on parenting of boys. Girls received significantly more positive parenting than boys. Differences in etiology of positive parenting may be explained by developmental gender differences in child cognitive abilities and affection, such that girls may have more rewarding interactions with parents, evoking more positive parenting.  相似文献   
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BACKGROUND: The optimal route for administration of exogenous erythropoietin remains controversial, particularly after the increased incidence in pure red cell aplasia. In Canada, the majority of hemodialysis units have converted to the intravenous route for administration of erythropoietin to potentially decrease the risk of pure red cell aplasia. OBJECTIVE: To compare the difference in the weight-adjusted, weekly erythropoietin dose (units/kg/wk) administered by the subcutaneous compared with the intravenous route in a chronic hemodialysis population followed for 12 months. METHODS: This prospective cohort study recruited patients receiving subcutaneous erythropoietin for at least 3 months while undergoing dialysis in a tertiary care hemodialysis program. Participants were switched to intravenous erythropoietin, and the average weekly dose was recorded at 1, 2, 3, 6, and 12 months. Anemia management and hemoglobin, iron, and delivered dialysis dose targets remained constant throughout the study. RESULTS: The erythropoietin dose increased by 24.5 units/kg/wk (95% CI 12.7 to 36.3; p < 0.001), representing a 20.2% increase (95% CI 10.5% to 29.9%; p < 0.001) 12 months after conversion from the subcutaneous to intravenous route of administration. Both patients with and without residual renal function at baseline required a significant increase in the intravenous dose. CONCLUSIONS: A 20.2% increase in erythropoietin dose was required to maintain hemoglobin targets between 11 and 12 g/dL after conversion from a subcutaneous to intravenous formulation. Healthcare funding agencies need to reexamine the cost benefit of using intravenous erythropoietin in the hemodialysis population with a low incidence of pure red cell aplasia.  相似文献   
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