【摘要】 目的　比较肿瘤细胞对 p(35 )Be快中子及γ射线的辐射敏感性 ,为肿瘤的快中子治疗提供理论依据。方法　用细胞集落存活方法研究人黑色素瘤细胞 (WM9839)、人口腔上皮癌细胞(KB)、人结肠腺癌细胞 (LS T 117)和人前列腺癌细胞 (PC3M )等 4种细胞对快中子及γ射线的辐射敏感性 ,用彗星电泳技术研究WM 9839细胞在快中子及γ射线照射后DNA损伤的修复效应。结果细胞存活实验表明 ,p(35 )Be快中子照射后 4种肿瘤细胞的D0 值 (或SF2 值 )较γ射线照射后差异减小 ,即 4种肿瘤细胞对快中子的辐射敏感性差异减小 ;快中子 2Gy照射后 ,WM 9839细胞DNA损伤修复曲线整体上下降较γ射线 2Gy照射后慢 ,到 180min时 ,DNA损伤残留率明显高于γ射线 2Gy照射。 结论　快中子治疗肿瘤可以很好地弥补低LET射线放射治疗的不足 ,特别是对低LET射线较为耐受的肿瘤细胞 ,如KB细胞和WM 9839细胞。更多还原

【Abstract】 Objective\ The difference of radiosensitivity of 4 human tumor cell lines to p(35)Be fast neutron and gamma ray was studied in order to provide basis for clinical therapy of tumors. Methods The radiosensitivity of these cell lines after p(35)Be neutron or gamma ray irradiation was assayed with cell colonogenic survival assay.And the gamma ray\|and p(35)Be neutron\|induced DNA damage and its repair in human melanoma cell line WM9839 was studied by using the method of comet\|electrophoresis assay. Results\ The difference of D\-0(or SF\-2) after p(35)Be neutron irradiation between these 4 human tumor cell lines was smaller than that after gamma ray irradiation.The repair rate of DNA damage in WM9839 cells after 2 Gy fast\|neutron irradiation was lower than that after 2 Gy γ\|ray irradiation.The residual DNA damage at 180 min after neutron\|irradiation was obviously severer than that after 2 Gy γ\|ray irradiation. Conclusion\ The fast neutron therapy may make up the defect of the low LET ray therapy,especially to those radioresistant tumor cells to low LET rays.\;更多还原