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641.
Epidermal naevi are common and can cause marked cosmetic disability. Ablative laser treatment may be successful in their removal, but may result in significant scarring. Surprisingly the erbium:YAG laser is rarely reported for this indication even though it produces minimal tissue damage. We report our experience using this laser to treat six patients with epidermal naevi. Patients (five female, one male; aged 4-41 years) underwent treatment with pulsed 2940 nm erbium:YAG laser at 0.4-0.45 J/cm(2), 2 mm spot size at 4 pulses/s. All six patients had excellent cosmetic results at follow up ranging from 6 to 60 months. The favourable results were dependent on selection of cases with superficial or small, discrete lesions which could be ablated accurately. The erbium:YAG laser is therefore an effective treatment for relatively nonverrucous or papular epidermal naevi.  相似文献   
642.
Sevelamer, or more precisely 'sevelamer hydrochloride', is a weakly basic anion-exchange resin in the chloride form that was introduced in 1997 for the treatment of the hyperphosphataemia of patients with end-stage renal failure, usually those on long-term haemodialysis. The rationale for this therapy was that sevelamer would sequester phosphate within the gastrointestinal tract, so preventing its absorption and enhancing its faecal excretion. Over the succeeding years, large numbers of patients have been treated with sevelamer, and it has fulfilled expectations in helping to control the hyperphosphataemia of end-stage renal failure. However, it is only one of many anion-exchange resins that could be used for this purpose, some of which are currently available for clinical use and are much less costly than sevelamer. Theoretical considerations suggest that some of these other resins might be at least as efficient as sevelamer in sequestering phosphate in the gastrointestinal tract. Neither sevelamer, nor any of these other agents, has been submitted to a proper metabolic balance study to measure the amount of phosphate sequestered by the resin in the bowel, and without this information it is impossible to judge which is the ideal resin for this purpose.  相似文献   
643.
Microalbuminuria and associated cardiovascular risk factors in the community.   总被引:11,自引:0,他引:11  
The prevalence of microalbuminuria and relationship to cardiovascular risk factors was examined in a cross-sectional community survey of cardiovascular risk factors. Microalbuminuria (when classified as albumin concentration greater than 20 micrograms/ml) was present in 6.3% of subjects but in conjunction with an albumin/creatinine ratio greater than 3.5 in only 2.2%. Diastolic blood pressure, prevalence of abnormal electrocardiographs, and to a lesser extent systolic blood pressure and fibrinogen concentration, were greater in those with albuminuria concentrations greater than 20 micrograms/ml. The strongest positive univariate correlates of albumin/creatinine ratios in those with detectable albuminuria were age, fibrinogen, blood pressure, total- and low density lipoprotein-(LDL) cholesterol, apo B and alcohol intake, whereas fasting insulin and insulin resistance were inversely correlated. Multiple regression analysis revealed that age, gender, systolic blood pressure and insulin resistance independently accounted for 37% of the variability in albumin/creatinine ratios. When those 10 subjects with microalbuminuria and albumin/creatinine ratios greater than 3.5 were matched with 20 with normoalbuminuria for age, gender and body mass index, the microalbuminuric subjects had significantly lower LDL cholesterol/apo B ratios and a tendency to lower high density lipoprotein (HDL) cholesterol and HDL cholesterol/apo A1 ratios. Microalbuminuria is uncommon in the general population, and is related to ageing, blood pressure and other vascular risk factors. It may reflect the presence of established cardiovascular disease.  相似文献   
644.
OBJECTIVES: In this study we aimed to define the rate of early surgery for Crohn's disease and to identify risk factors associated with early surgery as a basis for subsequent studies of early intervention in Crohn's disease. METHODS: We assembled a retrospective cohort of patients with Crohn's disease diagnosed between 1991 and 1997 and followed for at least 3 yr, who were identified in 16 community and referral-based practices in New England. Chart review was performed for each patient. Details of baseline demographic and disease features were recorded. Surgical history including date of surgery, indication, and procedure were also noted. Risk factors for early surgery (defined as major surgery for Crohn's disease within 3 yr of diagnosis, exclusive of major surgery at time of diagnosis) were identified by univariate analysis. Multiple logistic regression was used to identify independent risk factors. RESULTS: Of 345 eligible patients, 69 (20.1%) required surgery within 3 yr of diagnosis, excluding the 14 patients (4.1%) who had major surgery at the time of diagnosis. Overall, the interval between diagnosis and surgery was short; one half of all patients who required surgery underwent operation within 6 months of diagnosis. Risk factors identified by univariate analysis as significantly associated with early surgery included the following: smoking; disease of small bowel without colonic involvement; nausea and vomiting or abdominal pain on presentation; neutrophil count; and steroid use in the first 6 months. Disease localized to the colon only, blood in the stool, use of 5-aminosalicylate, and lymphocyte count were inversely associated with risk of early surgery. Logistic regression confirmed independent associations with smoking as a positive risk factor and involvement of colon without small bowel as a negative risk factor for early surgery. CONCLUSIONS: The rate of surgery is high in the first 3 yr after diagnosis of Crohn's disease, particularly in the first 6 months. These results suggest that improved risk stratification and potent therapies with rapid onset of action are needed to modify the natural history of Crohn's disease.  相似文献   
645.
A detailed pathological study of the coronary arteries was carried out on 130 random white subjects (91 male and 39 female) who died suddenly in the Glasgow area. In 30 there was a clearly defined cause of death that was not due to ischaemic heart disease. In eight subjects the cause of death was in doubt. Ninety two of the 130 showed coronary stenosis resulting in a loss of more than 75% of coronary artery cross sectional area and/or acute coronary events with no other cause of death. Of these 92 subjects considered to have died suddenly of ischaemic heart disease, 64% showed plaque rupture and thrombosis which occurred at sites of previous high grades of stenosis. Twenty two subjects had intraluminal thrombosis unrelated to plaque fissuring. Thirty eight (41%) showed histological evidence of recent myocardial necrosis; acute coronary events occurred in 34 of these. There was no correlation between the duration of symptoms before death and the occurrence of acute coronary events. Acute coronary events, mainly in the form of plaque rupture, are a common finding in sudden coronary death when a careful study is made of the whole coronary arterial tree.  相似文献   
646.
A detailed analysis of the extent of coronary artery atherosclerosis was made in 92 white subjects (66 men and 26 women) who died suddenly from ischaemic heart disease. Stenoses resulting in loss of greater than or equal to 75% of luminal cross sectional area (significant stenosis) were found in 90 subjects and these were more extensive in the proximal coronary tree than in the distal. Thirty nine per cent had triple vessel disease, 37% had double vessel disease, and 23% had single vessel disease. In addition one man had an isolated significant stenosis affecting the left main coronary artery. The frequency of significant stenoses in the left main coronary artery was greater in men than in women. The arteries that were least affected were the distal branches of the right coronary artery. A notable feature was the widespread nature of the coronary atherosclerosis: only 26 of the total of 1840 segments of coronary artery examined in the 92 victims could be described as having a normal intima (less than or equal to 10% loss of the area within the internal elastic lamina).  相似文献   
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