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11.
Richard Frazee M.D. Glennon Einspanier D.O. Mitchell S. Wachtel M.D. Eldo E. Frezza M.D. M.B.A. F.A.C.S. 《Surgery for obesity and related diseases》2007,3(2):191-175
BACKGROUND: Gastric bypass is an established bariatric procedure that has undergone multiple modifications to improve its effectiveness. The side-to-side stapled technique is well recognized, but closure of the gastrotomy/enterotomy by the stapler can potentially narrow the Roux limb. Because of this, many surgeons will hand suture the closure of the gastrotomy/enterotomy. To obviate this difficulty, we inserted the linear stapler from the stomach's greater curvature, using a double-stapled anastomosis that minimized the need for hand suturing. METHODS: We performed a retrospective analysis of 307 patients undergoing this technique for laparoscopic gastric bypass. The weight loss and 30-day morbidity and mortality were tabulated and compared with those in other published series. RESULTS: Of the 307 patients, none died postoperatively. The overall 30-day morbidity rate was 15%. Two leaks from the gastrojejunostomy and 2 from the jejunojejunostomy (1.2%) developed. The mean percentage of excess weight loss was 34% at 3 months, 52% at 6 months, 73% at 1 year, 71% at 2 years, and 69% at 3 years. CONCLUSION: The greater curve approach avoids Roux limb obstruction, minimizes the need for hand suturing, and uses standard trocar incisions. Our short-term follow-up results are similar to those of series of other techniques. 相似文献
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辛伐他汀对人低密度脂蛋白氧化修饰影响的实验研究 总被引:2,自引:2,他引:0
目的研究辛伐他汀在体外对低密度脂蛋白氧化修饰的影响.方法以低密度脂蛋白氧化修饰为模型,以硫代巴比妥酸反应物质(TBARS)生成量及相对电泳迁移率(REM)为指标,研究了辛伐他汀对铜离子(Cu2 )诱导低密度脂蛋白氧化修饰的抑制作用.结果随辛伐他汀浓度从1~10μmol/L的增加,TBARS值分别减少67.3%,73.9%,81.9%,REM值减少48.3%,55.2%,58.6%,呈浓度及时间依赖关系.其中10μmol/L辛伐他汀可几乎完全抑制低密度脂蛋白氧化.结论辛伐他汀在体外能明显抑制Cu2 诱导的低密度脂蛋白氧化修饰. 相似文献
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OBJECTIVE: The purpose of this study was to characterize the etching behavior of titanium in concentrated sulfuric acid and discuss its application on surface modification of titanium for biological use. METHODS: Commercially pure titanium (cpTi) plate was etched in 48% H2SO4 at RT -90 degrees C for 0.25-8 h. The weight loss was derived from the weight differences before and after etching. The surfaces after etching were characterized by surface roughness, X-ray diffractometry, and scannning electron spectroscopy. The apparent activation energy of the dissolution of cpTi into acid was derived from an Arrhenius plot of the rate of weight loss versus the acid temperature. RESULTS: The surface roughness of cpTi increased with the acid temperature and etching time. The surface roughness was strongly related to the weight loss. The weight loss increased drastically with the acid temperature after an initial period, which shortened with increasing acid temperature. The apparent activation energy for the dissolution of cpTi in H2SO4 was derived as 67.8 kJ/mol. SIGNIFICANCE: This study indicates that etching with concentrated sulfuric acid is an effective way to modify the surface of titanium for biological applications. 相似文献
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高性能战斗机改装体检飞行员的耳功能分析 总被引:6,自引:3,他引:3
目的 分析高性能战斗机改装体检飞行员的咽鼓管功能、前庭功能和听功能状况。方法 对改装体检的196名飞行员的耳功能资料进行分析。结果 ①声导抗示196例392耳中193例368耳为A型曲线,6例7耳为AD型曲线,15例17耳为C型曲线。196例392耳均无声反射衰减;②眼震电图示196例前庭功能均正常:③纯音测听以气导在500、1000、2000、3000Hz的平均听阈表示,196例的结果为左耳12.58dB HL;右耳12.48dB HL,但37例47耳有高频区噪声性听损伤的表现。结论 参与高性能战斗机改装体检的飞行员,其耳功能状况总体良好,但部分有噪声性听损伤的应随访观察。 相似文献
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通过溴化聚苯醚和格利雅试剂反应,将不饱和基团烯丙基引入聚苯醚中实现其热固性改性,由^1H-NMR和FTIR进行结构表征。确定了烯丙化聚苯醚的固化工艺,并对其固化产物性能进行测试。结果表明:按合成新工艺制备的热固性聚苯醚,其固化产物具有优异的介电性能(低介电常数、低介电损耗因子),良好的耐溶剂性能和低吸湿性。 相似文献
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次氯酸对人血清白蛋白的氧化修饰影响及与高级氧化蛋白产物的关系 总被引:2,自引:0,他引:2
目的 研究次氯酸对人血清白蛋白(HSA)的氧化修饰影响及与高级氧化蛋白产物(AOPPs)之间的关系。 方法 有氧条件下在恒定浓度的HSA(60 mg/ml)内加入不同浓度次氯酸(0、1、5、10、20、30、40、50、60 mmol/L,最终浓度),观察氧化剂对HSA的修饰作用。凝胶排阻色谱法检验HSA氧化修饰结果,在线光谱扫描(190 nm~400 nm)分析修饰产物的光谱特性。结果 次氯酸可氧化修饰人血清白蛋白,其修饰产物主要为二聚体HSA和六聚体HSA。发现次氯酸对HSA单体和HSA二聚体的氧化修饰为一级反应;对诱导生成的AOPPs为准一级反应;而对诱导生成的HSA六聚体则为二级修饰反应。同时发现白蛋白对AOPPs的主要贡献者是六聚体形式的HSA,光谱分析表明HSA聚集体的最大吸收峰发生红移,提示HSA聚集体是由于蛋白中的酪氨酸残基通过氧化交联方式而聚集形成的。 结论 HSA经次氯酸处理后主要发生了蛋白聚集。而对AOPPs的主要贡献者是六聚体形式的HSA。 相似文献
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I. Ibarrola M. L. Sanz† P. M. Gamboa‡ A. Mir§ D. Benahmed§ A. Ferrer¶ M. C. Arilla A. Martínez J. A. Asturias 《Clinical and experimental allergy》2004,34(2):303-309
BACKGROUND: Allergoids are widely used in specific immunotherapy (SIT) for the treatment of IgE-mediated allergic diseases, but all techniques for standardization of conventional allergic extracts may not be appropriate for standardization of a glutaraldehyde (GA)-modified extract because of the unique characteristics of these extracts. OBJECTIVE: To assess an accurate methodology for standardization of chemically modified extracts. METHODS: GA-modified extracts from Parietaria judaica pollen were purified by diafiltration. Biochemical properties were investigated by determination of amino groups, chromatography, and SDS-PAGE. The IgE-binding activity was determined by skin prick test, enzyme allergosorbent test inhibition, basophil activation, and histamine release tests. Peripheral blood mononuclear cells (PBMCs) from P. judaica pollen-allergic subjects were stimulated with either native or allergoid extracts, and proliferation was measured. RESULTS: Biochemical data indicated a high degree of allergen polymerization resulting in extract components higher than 100 kDa. IgE-binding activity, both in vivo and in vitro, was reduced by more than 99.8%. Both allergen and allergoid induced PBMC proliferation and synthesis of blocking IgG antibodies at similar rates. Moreover, no evidence of introduction of new determinants by chemical modification was found. CONCLUSIONS: The preparation of GA-modified extracts by diafiltration is faster and more reliable than previous chromatographic methods. These modified extracts have drastically reduced their allergenicity while maintaining their immunogenicity, and therefore they can be used in safer and shortened schedules of SIT. 相似文献