不同材料内植物对放射治疗影响的研究

目的:探讨不同材料内植物对放射治疗的影响.方法:采用6MV-X线作为放射源,在体外对形状、大小及厚度相同的镍钛合金板、不锈钢板、钛板和骨水泥板的透射因子进行测定,以确定不同材料内植物对射线的阻挡情况.结果:4种不同材料内植物对射线的衰减影响很小,但不同材料内植物对射线的衰减有显著性差异(P<0.05).结论:4种不同材料内植物对射线的衰减有显著性差异,以骨水泥的影响最小,钛板次之,不锈钢板、镍钛合金最大,因此恶性骨肿瘤保肢手术,术后需要放射治疗的患者,选用骨与关节替代材料时可优先选择骨水泥和钛板.     

Hyperthermia by a nitinol stent in an alternating magnetic field:Safety and feasibility in rabbit esophageal cancer

Hyperthermia by heating in-stent is a potentially new method to treat esophageal cancer.This study assessed the safety of heating the rabbit esophagus with a nitinol stent in an alternating magnetic field (AMF) and investigated whether this method offers a therapeutic option for esophageal cancer.Nitinol stents were placed in the cervical esophagi of healthy rabbits,which were heated in an AMF for different times at 43,46 and 50 ℃.The esophagi were histologically examined after a week to observe whether there was transmural necroses.Then esophageal cancer of rabbit placed nitinol stents were heated in an AMF at 46℃ for 10 min.Stents were heated to a target temperature within 5 min.The highest tolerated temperature and time for the healthy rabbit esophagus was at 46℃ for 10 min.Tumor growth was delayed by heating and it was statistically significant.Heating the rabbit esophageal wall at 46℃ for 10 min proves to be safe and effective in delaying tumor growth.     

形变医用镍钛合金表面TiN涂层耐蚀性的研究

在37℃的人造血浆中,研究了有无TiN涂覆层的镍钛合金的耐蚀性。电化学实验显示TiN涂层能使其相对饱和甘汞电极的电位从0.95 V增至1.5 V,其腐蚀电流密度从0.20 mA/cm2降至0.10 mA/cm2。溶解的钛离子和镍离子的化合价为正二价。变形量小于6%时,镍钛基TiN膜层的耐蚀性并未受到严重影响。由于变形产生的TiN膜层裂纹而导致了轻微的腐蚀,但其耐蚀性仍好于没有TiN膜层的镍钛合金,因为在裂纹处未观察到电偶腐蚀。