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Site selection for fat autotransplantation: Some observations   总被引:4,自引:0,他引:4  
The use of autologous fat for implantation has recently received renewed attention in the plastic surgery literature. Autologous fat reportedly has been used for the treatment of wrinkles and Romberg's disease, and for buttock and breast augmentation. While some measure of success has been achieved, many surgeons report that substantial resorption of fat tissue occurs at the site of implantation. There is lack of unanimity regarding the ideal site for extraction or injection in order to minimize fat resorption. Adipose tissue samples were taken from women undergoing surgical procedures on the abdomen, gluteal-femoral region, and breast. Facial adipose tissue samples from men and women were also analyzed. Adipocytes were isolated chemically and sized microscopically. Activity of the lipogenic enzyme adipose tissue lipoprotein lipase (ATLPL) was measured in frozen samples. Results suggest that femoral site samples are somewhat larger (NS) and have greater lipogenic activity (p<0.03) than other sites. In our study, small facial samples had very low or unmeasurable levels of ATLPL activity. Perhaps cell size and lipogenic activity should be considered when selecting tissues for autotransplantation.  相似文献   
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A necrotic liver abscess model was studied with magnetic resonance (MR) imaging at 1.5 T before and after intravenous administration of gadoteridol at doses of 0.1, 0.25, and 0.5 mmol/kg in 24 rabbits. Enhancement characteristics and lesion delineation were assessed with both breath-hold and non-breath-hold imaging techniques. Lesion delineation, as assessed both by signal intensity measurements and evaluations by two image readers blinded to imaging technique, was greatest on high-dose (0.5 mmol/kg) breath-hold images. Lesion rim enhancement was seen consistently only on postcontrast images obtained at a dose of 0.5 mmol/kg and progressed with time after injection of contrast material.  相似文献   
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The ability of extracts of a range of cell lines to release methylated bases from a DNA substrate, which had been modified with [3H]dimethyl sulphate, has been compared in cell lines with differing sensitivity to the cytotoxic drug, temozolomide. High performance liquid chromatography profiles of the bases released by these extracts showed that the activity was specific for 3-methyladenine. There was little variation in the level of 3-methyladenine-DNA glycosylase between the different cell lines despite a 40-fold difference in sensitivity to temozolomide and no correlation with the level of O6-alkylguanine-DNA alkyltransferase.  相似文献   
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A series of clinicopathological variables was assessed on 312 patients undergoing surgical resection for primary colorectal cancer. Although the presence of venous invasion was related to mortality (P = 0.02), classifying invasion into involvement of thick-walled or thin-walled veins did not produce a variable of prognostic value. Intestinal obstruction (P = 0.04) and the macroscopic appearance of the tumour (P = 0.04) were related to mortality from colorectal cancer, but not from all causes of death. Duke''s stage, increasing patient age and poorly differentiated tumours were the variables which were individually most significantly related to poor prognosis (P < 0.001 for each analysis). Cox''s regression analysis identified these three variables as independent predictors of outcome in colorectal cancer. This study confirms that Duke''s stage, patient age and tumour differentiation are still the most important clinicopathological variables in colorectal cancer.  相似文献   
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