目的:研究不同CT层厚对射波刀放疗靶区剂量分布的影响。方法:(1)使用胸部仿真模体对不同大小模拟肿瘤TUMOR01~TUMOR05以1.0~5.0 mm CT层厚行常规CT模拟定位和重建;(2)使用各模拟肿瘤不同层厚CT序列以固定Auto-Shells、处方剂量、处方剂...目的:研究不同CT层厚对射波刀放疗靶区剂量分布的影响。方法:(1)使用胸部仿真模体对不同大小模拟肿瘤TUMOR01~TUMOR05以1.0~5.0 mm CT层厚行常规CT模拟定位和重建;(2)使用各模拟肿瘤不同层厚CT序列以固定Auto-Shells、处方剂量、处方剂量线及限光筒制定射波刀放疗计划,记录放疗靶区计算结果;(3)分别将各模拟肿瘤不同CT层厚放疗计划移植至1.0 mm CT层厚放疗计划,记录放疗计划移植后放疗靶区变化结果;(4)比较各模拟肿瘤不同CT层厚放疗计划移植前后放疗靶区的变化情况。结果:除模拟肿瘤TUMOR01放疗靶区最大剂量(D_(max))与CT层厚表现为弱相关性(|r|=0.20)外,模拟肿瘤TUMOR02~TUMOR05放疗靶区D_(max)及各模拟肿瘤放疗靶区最小剂量(D_(min))、适形度指数(CI)、新适形度指数(nCI)、覆盖率Coverage与CT层厚均表现为强相关性(|r|>0.70),各模拟肿瘤放疗靶区D_(min)、覆盖率Coverage与CT层厚呈负相关,放疗靶区D_(max)、CI、nCI与CT层厚呈正相关,其相关显著性水平不同;当模拟肿瘤TUMOR01 CT层厚>2 mm时,放疗靶区D_(min)、nCI、覆盖率Coverage数值变化尤为明显,其变化范围分别为9.89~15.29Gy、0.19~0.76、11.44%~29.94%。结论:CT层厚显著影响射波刀放疗靶区剂量分布,对体积较小肿瘤的影响尤为明显。展开更多
The ion implantation technique was employed to study the structural,magnetic,and optical properties of Co-doped crystalline ZnO.The photoluminescence measurements indicated that the center of green emission of implant...The ion implantation technique was employed to study the structural,magnetic,and optical properties of Co-doped crystalline ZnO.The photoluminescence measurements indicated that the center of green emission of implanted samples shifts gradually from 510 nm to 531 nm with an increase of Co concentrations.All implanted samples are ferromagnetic at room temperature with a saturation magnetization from 6.89×10-5 to 2.31×10-4 emu.The possible mechanisms on the observed ferromagnetism were discussed.展开更多
文摘目的:研究不同CT层厚对射波刀放疗靶区剂量分布的影响。方法:(1)使用胸部仿真模体对不同大小模拟肿瘤TUMOR01~TUMOR05以1.0~5.0 mm CT层厚行常规CT模拟定位和重建;(2)使用各模拟肿瘤不同层厚CT序列以固定Auto-Shells、处方剂量、处方剂量线及限光筒制定射波刀放疗计划,记录放疗靶区计算结果;(3)分别将各模拟肿瘤不同CT层厚放疗计划移植至1.0 mm CT层厚放疗计划,记录放疗计划移植后放疗靶区变化结果;(4)比较各模拟肿瘤不同CT层厚放疗计划移植前后放疗靶区的变化情况。结果:除模拟肿瘤TUMOR01放疗靶区最大剂量(D_(max))与CT层厚表现为弱相关性(|r|=0.20)外,模拟肿瘤TUMOR02~TUMOR05放疗靶区D_(max)及各模拟肿瘤放疗靶区最小剂量(D_(min))、适形度指数(CI)、新适形度指数(nCI)、覆盖率Coverage与CT层厚均表现为强相关性(|r|>0.70),各模拟肿瘤放疗靶区D_(min)、覆盖率Coverage与CT层厚呈负相关,放疗靶区D_(max)、CI、nCI与CT层厚呈正相关,其相关显著性水平不同;当模拟肿瘤TUMOR01 CT层厚>2 mm时,放疗靶区D_(min)、nCI、覆盖率Coverage数值变化尤为明显,其变化范围分别为9.89~15.29Gy、0.19~0.76、11.44%~29.94%。结论:CT层厚显著影响射波刀放疗靶区剂量分布,对体积较小肿瘤的影响尤为明显。
基金supported by the National Natural Science Foundation of China (Grant No. 10375028)the Open Project of Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education,Lanzhou University,and the SRF for ROCS,SEM
文摘The ion implantation technique was employed to study the structural,magnetic,and optical properties of Co-doped crystalline ZnO.The photoluminescence measurements indicated that the center of green emission of implanted samples shifts gradually from 510 nm to 531 nm with an increase of Co concentrations.All implanted samples are ferromagnetic at room temperature with a saturation magnetization from 6.89×10-5 to 2.31×10-4 emu.The possible mechanisms on the observed ferromagnetism were discussed.
