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Calciphylaxis – a topical overview   总被引:3,自引:0,他引:3  
'Calciphylaxis', a calcification syndrome associated with ischaemic cutaneous necrosis, is acquired naturally in humans in disease states. It is a life and limb-threatening complication, usually observed in patients with renal disease and secondary hyperparathyroidism, but known to occur in the absence of renal or parathyroid disease. The reported mortality rate, which ranges from 60-80%, relates to wound infection, sepsis and organ failure. It is a small-vessel vasculopathy, which is estimated to occur in about 4% of haemodialysis patients. Clinically, violaceous, reticulate areas of cutaneous necrosis and eschar may be evident, particularly in the extremities. In addition to the clinical picture, a raised calcium phosphorous product, an elevated parathyroid hormone level, radiographic evidence of vessel and soft-tissue calcification and the finding of mural calcification affecting small arteries and arterioles on histopathology help to confirm the diagnosis of this entity which generally has a poor prognosis. A high index of suspicion and an active multidisciplinary management approach, with rigorous attention to wound care and prevention of sepsis, are vital in the management of these patients. In this overview, we discuss the pathophysiology, clinical features and associations, risk factors, diagnosis and management issues relating to calciphylaxis.  相似文献   
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Since 1982 eight patients under 1 year of age with end-stage renal failure have been treated by chronic peritoneal dialysis (CPD) following insertion of an abdominal Tenckhoff catheter. We routinely perform a partial omentectomy now, and in males undertake bilateral exploration of the groins at the time of catheter insertion, with herniotomy or ligation of the patent processus vaginalis as required. Up to January 1990, 19 straight double-cuff catheters had been inserted with a total follow-up of 244.5 patient months. The median age at the initial catheter insertion was 14.6 weeks (range, 2 days to 11 months) and the median weight was 3.89 kg (range, 2.2 to 5.5). Peritonitis was the most common complication, with 46 episodes, representing one episode of peritonitis per 5.3 patient months on dialysis. The frequency of peritonitis has decreased in the last 6 months since all patients have been dialysed by two caregivers. The present rate of peritonitis is 1 episode per 10 patient months on dialysis. One patient has died of septicemia secondary to associated congenital abnormalities, one patient has regained renal function, and two patients have been transplanted, one successfully. Five patients are currently dialysing via their abdominal Tenckhoff catheters and awaiting transplantation. We conclude that neonates and infants under 1 year of age can be treated satisfactorily by CPD to enable successful preparation for transplantation later in childhood.  相似文献   
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Backround  

Diverticulosis is a common disease in the western society with an incidence of 33–66%. 10–25% of these patients will develop diverticulitis. In order to prevent a high-risk acute operation it is advised to perform elective sigmoid resection after two episodes of diverticulitis in the elderly patient or after one episode in the younger (< 50 years) patient. Open sigmoid resection is still the gold standard, but laparoscopic colon resections seem to have certain advantages over open procedures. On the other hand, a double blind investigation has never been performed. The Sigma-trial is designed to evaluate the presumed advantages of laparoscopic over open sigmoid resections in patients with symptomatic diverticulitis.  相似文献   
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OBJECTIVE: To describe information requests expressed during clinical teaching. SETTING: Residents' work rounds, attending rounds, morning report, and interns' clinic in a university-based general medicine service. SUBJECTS: Attending physicians, medical house staff, and medical students in a general medicine training program. METHODS: An anthropologist observed communication among study subjects and recorded in field notes expressions of a need for information. We developed a coding scheme for describing information requests and applied the coding scheme to the data recorded. Based on assigned codes, we created a subset of strictly clinical requests. MEASUREMENTS: Five hundred nineteen information requests recorded during 17 hours of observed clinical activity were selected for detailed analysis. These requests related to the care of approximately 90 patients by 24 physicians and medical students. Sixty-five requests were excluded because they were not strictly clinical, leaving a subset of 454 clinical questions for analysis. MAIN RESULTS: On average, five clinical questions were raised for each patient discussed. Three hundred thirty-seven requests (74%) concerned patient care. Of these 337 questions, 175 (52%) requested a fact that could have been found in a medical record. Seventy-seven (23%) of these questions, motivated by the needs of patient care, were potentially answerable by a library, a textbook, a journal, or MEDLINE. Eighty-eight (26%) of the questions asked for patient care required synthesis of patient information and medical knowledge. CONCLUSIONS: Clinicians in the study settings requested information frequently. Many of these information needs required the synthesis of patient information and medical knowledge and thus were potentially difficult to satisfy. A typology is proposed that characterizes information needs as consciously recognized, unrecognized, and currently satisfied.  相似文献   
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