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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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Imaging of renal transplants   总被引:1,自引:0,他引:1  
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The characteristics and outcome of pregnancy complicated by gestational glucose intolerance are described in a consecutive series of 69 Bengali Asian patients and a parallel group of 22 Caucasian patients. The Bengali patients were older and of higher parity than the Caucasians and more frequently required insulin therapy. However, the outcome of pregnancy was similar in terms of antenatal clinic attendance, the number of antenatal hospital admissions, glycaemic control, birthweight and mode of delivery. Of those patients who attended for postnatal glucose tolerance test, 20% of the Bengali population demonstrated persisting abnormality of glucose tolerance, whereas no abnormalities were evident in the Caucasian group. These findings are consistent with the high prevalence and early age of onset of non-insulin-dependent diabetes in Asian populations. The World Health Organisation (WHO) criteria for the diagnosis of impaired glucose tolerance proved insufficiently sensitive for the diagnosis of gestational diabetes. This was particularly demonstrated by four patients with apparently normal glucose tolerance by WHO criteria who subsequently required insulin therapy.  相似文献   
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Stimulation of the human motor cortex through the scalp   总被引:24,自引:0,他引:24  
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R Kino  R O Day  G A Pearce  G W Fulde 《Chest》1991,100(6):1572-1577
An experimental technique designed to predict theophylline doses needed to attain therapeutic theophylline concentrations in 43 emergency department (ED) patients was compared with a standard conventional regimen in 46 ED patients. The experimental protocol utilized a computer-assisted dosage prediction program that incorporated baseline theophylline concentration rapidly obtained using a bedside assay. The standard protocol used conventional loading and infusion rates, as well as an estimate of time of last theophylline dose based on patient history. Plasma theophylline concentrations, estimated 1 and 6 hours after commencement of aminophylline therapy in each regimen, were compared. The experimental protocol was equally rapid but much more accurate in achieving targeted theophylline concentrations. Experimental dosage prediction was associated with a higher proportion of theophylline concentrations in the therapeutic range at 1 (81 percent vs 26 percent; p less than 0.001) and 6 hours (91 percent vs 37 percent; p less than 0.001). There was a trend toward fewer toxic concentrations recorded at 1 (0 percent vs 7 percent; p = 0.27) and 6 hours (0 percent vs 10 percent; p = 0.08). This protocol, which was performed quickly and without difficulty by residents in a busy hospital ED, offers an opportunity to improve the efficacy and decrease the toxicity of theophylline use in asthma emergencies.  相似文献   
40.
Second primary tumors in patients with oral cancer.   总被引:7,自引:0,他引:7  
G L Day  W J Blot 《Cancer》1992,70(1):14-19
BACKGROUND. Patients with cancer of the oral cavity and pharynx have been described to be particularly susceptible to the development of new cancers. METHODS. Using data collected during 1973-1987 by nine population-based cancer registries in the United States, the authors evaluated risks of second primary cancers among 21,371 patients in whom oral and pharyngeal cancers were diagnosed. RESULTS. The rate of development of second tumors was 3.7% per year. The risk of a second primary cancer was 2.8 times greater than expected, with 20-fold excesses of second oral or esophageal cancers and 4-fold to 7-fold increases of respiratory cancers. Increased risks persisted unabated for cancers diagnosed 5 or more years after oral cancer, suggesting that the second cancers were new primary tumors and not misdiagnosed metastases. The increased risks of second primary tumors were found among both men and women and black and white patients; they were most prominent among patients who were 60 years or younger. CONCLUSIONS. The exceptionally high rate of cancer recurrence among patients with oral cancer (exceeding that for all other cancers) points to the need for close medical surveillance. Special emphasis should be placed on advising patients to avoid or limit consumption of tobacco and alcohol, the main risk factors for oral and most second cancers.  相似文献   
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