目的制备一种黏性载体和成骨基质颗粒均来源于人骨的可塑形骨填充材料,通过动物实验评价其安全性和骨诱导能力。方法取自愿捐赠的人体长骨,采用粉碎、清洗、脱矿等方法制备脱钙骨基质(demineralized bone matrix,DBM)颗粒,再将DBM颗粒...目的制备一种黏性载体和成骨基质颗粒均来源于人骨的可塑形骨填充材料,通过动物实验评价其安全性和骨诱导能力。方法取自愿捐赠的人体长骨,采用粉碎、清洗、脱矿等方法制备脱钙骨基质(demineralized bone matrix,DBM)颗粒,再将DBM颗粒经温浴法制备骨基质明胶(bone matrix gelatin,BMG),将BMG及DBM颗粒混合制备成可塑形骨填充材料(实验组);以单纯DBM颗粒作为对照组。取15只6~9周龄健康雄性无胸腺裸小鼠,于两侧臀中肌与臀大肌间制备肌间空隙,均植入实验组材料,术后1、4、6周处死动物,行HE组织学染色评价异位成骨效果。取8只9月龄日本大耳兔,于两侧后肢髁骨处制备直径6 mm骨缺损,左、右侧分别填充实验组和对照组材料,术后12、26周处死动物,行Micro-CT及HE组织学染色评价骨缺损修复效果。结果异位成骨实验HE染色示,术后1周可观察到大量软骨细胞,术后4、6周可观察到明显新生软骨组织。兔髁骨缺损修复实验HE染色示,术后12周,部分材料被吸收,实验组及对照组均可观察到新生软骨;术后26周,大部分材料被吸收,对照组可观察到大量新生骨,实验组可观察到新生骨单元结构。Micro-CT观测示,实验组成骨速率及成骨面积均优于对照组。骨形态计量学参数检测示,两组术后26周各参数均较术后12周显著增加(P<0.05)。术后12周,实验组骨密度、骨体积分数均显著高于对照组(P<0.05),两组骨小梁厚度差异无统计学意义(P>0.05);术后26周,实验组骨密度显著高于对照组(P<0.05),两组骨体积分数、骨小梁厚度差异无统计学意义(P>0.05)。结论新型可塑形骨填充材料具有良好的生物安全性及骨诱导活性,是一种良好的骨填充材料。展开更多
A new process of hydroforming with controllable radial pressure was proposed to overcome difficulties in the forming of low plastic materials and large height-to-diameter ratio workpieces. A typical 5A06 aluminum allo...A new process of hydroforming with controllable radial pressure was proposed to overcome difficulties in the forming of low plastic materials and large height-to-diameter ratio workpieces. A typical 5A06 aluminum alloy dome was numerically and experimentally investigated. The reasons for typical defects were analyzed under different radial pressures. Effects of radial pressure on the thickness distribution were discussed and optimal radial pressure was determined. It is shown by numerical simulations and experiment that a cup with a drawing ratio of 2.4 is formed by the new process of hydroforming with controllable radial pressure. It is significantly effective for the forming of low plastic materials and large height-to-diameter ratio workpieees. Two typical thinning points exit along the dome wall. With the radial pressure, thinning is decreased effectively at the two points, the dome forming is achieved and thickness distribution is more uniform.展开更多
基金Projects(50525516, 50875062 ) supported by the National Natural Science Foundation of China
文摘A new process of hydroforming with controllable radial pressure was proposed to overcome difficulties in the forming of low plastic materials and large height-to-diameter ratio workpieces. A typical 5A06 aluminum alloy dome was numerically and experimentally investigated. The reasons for typical defects were analyzed under different radial pressures. Effects of radial pressure on the thickness distribution were discussed and optimal radial pressure was determined. It is shown by numerical simulations and experiment that a cup with a drawing ratio of 2.4 is formed by the new process of hydroforming with controllable radial pressure. It is significantly effective for the forming of low plastic materials and large height-to-diameter ratio workpieees. Two typical thinning points exit along the dome wall. With the radial pressure, thinning is decreased effectively at the two points, the dome forming is achieved and thickness distribution is more uniform.
