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Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence. 相似文献
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Noninvasive metabolic magnetic resonance (MR) imaging reflecting glucose metabolism in the aldose-reductase-sorbitol (ARS) pathway was performed in the rabbit head; after administration of the fluorinated glucose analogue 3-fluoro-3-deoxy-D-glucose (3FD-glucose), fluorine-19 images were generated. Images of 3FD-glucose showed significant 3FD-glucose uptake by adipose tissue, indicating its buffering effects in case of excess loads of glucose. Images of 3-fluoro-3-deoxy-D-sorbitol (3FD-sorbitol) demonstrated the spatial distribution of aldose reductase activities and significant sorbitol accumulation in the lens. Images of 3-fluoro-3-deoxy-D-fructose (3FD-fructose) showed preferential uptake of fructose by muscle tissue. The extremely low toxicity of 3FD-glucose indicates promise for its clinical application in metabolic imaging. 相似文献
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目的:血小板衍生生长因子在平滑肌细胞的表型转化过程中起重要作用。观察大鼠移植心脏组织中血小板衍生生长因子AmRNA表达的变化及雷帕霉素的干预效应。方法:实验于2005-10/2006-01在中南大学湘雅二医院胸心外科实验室完成。将60只SD大鼠、24只Wistar大鼠按随机数字表法分为3组:①同系移植组:供、受体各12只,均为SD大鼠。②异系移植组:供体为Wistar大鼠(n=24),受体为SD大鼠(n=24),受体大鼠随机分为雷帕霉素组(n=12)和环孢霉素组(n=12),术后分别给予雷帕霉素1.25mg/(kg·d)灌胃及环孢霉素A10mg/(kg·d)皮下注射,给药60d,给药结束后留取移植心脏待检。③另12只SD大鼠直接取心脏组织作为正常对照组。指标检测:①对移植心脏组织行VanGieson染色后采用Miassystem4.1医学图像分析管理系统分析血管狭窄程度。②应用反转录-聚合酶链反应检测血小板衍生生长因子AmRNA在移植心脏组织中的表达情况。结果:36只受体SD大鼠及12只正常SD大鼠全部进入结果分析,无脱失。①同系移植组、环孢霉素组及雷帕霉素组大鼠的冠状动脉狭窄指数均显著高于正常对照组[(13.12±0.72)%,(62.45±8.12)%,(28.91±3.24)%,(0.09±0.02)%(P<0.01)],环孢霉素组及雷帕霉素组高于同系移植组(P<0.05),环孢霉素组高于雷帕霉素组(P<0.01)。②正常对照组、同系移植组、环孢霉素组及雷帕霉素组大鼠的血小板衍生生长因子AmRNA相对含量分别为0.19±0.06,0.21±0.08,1.12±0.22及0.47±0.11,环孢霉素组、雷帕霉素组显著高于同系移植组(P<0.01),环孢霉素组高于雷帕霉素组(P<0.05)。结论:血小板衍生生长因子AmRNA的高表达与移植心脏的血管硬化有关;雷帕霉素具有预防大鼠心脏移植物血管病变的作用,其作用可能与抑制心脏组织中血小板衍生生长因子AmRNA的表达有关。 相似文献
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Datar RA Rueggeberg FA Caughman GB Wataha JC Lewis JB Schuster GS 《Journal of biomaterials science. Polymer edition》2005,16(10):1293-1302
The biological effects of camphorquinone (CQ), an initiator for light-polymerized resins, have been reported to relate to its ability to generate free radicals and cause radical-induced membrane damage via lipid peroxidation. However, the effects of CQ on lipids other than peroxidation may result in unfavorable tissue responses especially at concentrations that are not overtly toxic to cells. The purpose of the current study was to examine the effects of CQ on cell lipid metabolism at subtoxic concentrations, with or without visible light irradiation. HCP and THP-1 cells were exposed to CQ with or without light irradiation under clinically relevant conditions and lipid metabolism was analyzed using 14C-labeling and thin-layer chromatography. We found that CQ increased synthesis of neutral lipids, such as triglycerides, from 7 to nearly 15% of the total and diglycerides from 2% to about 3% of the total in HCP cells, while synthesis of phospholipids, such as sphingomyelin, was decreased by 1-1.5%. In THP-1 cells cholesterol synthesis increased more than 2-fold and cholesterol ester synthesis increased more than 5-fold. Light-activated CQ did not differ significantly in terms of its bioactivity compared to no-light conditions. We conclude that CQ significantly altered the metabolism of several important structural lipids in two cell types at sub-toxic concentrations that are clinically relevant. These changes in lipid metabolism may in turn affect membrane integrity and permeability and possibly lead to significant changes in cell responses. 相似文献
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