中文摘要：

为探讨kras基因与辐射诱发小鼠胸腺淋巴瘤的关系，先采用X射线照射BALB／c小鼠建立胸腺淋巴瘤模型，取胸腺淋巴瘤和正常胸腺，分别提取总RNA、合成cDNA和提取总蛋白，采用实时定量PCR（Quantitativ ereal—time PCR．QRT-PCR）和Westernblot法对kras基因mRNA和蛋白表达分别进行检测。结果表明，胸腺淋巴瘤kras基因mRNA表达水平（2．66±1．51）比正常胸腺组织（0．93±0．30）明显增高，两组比较有统计学意义（p〈O．05），胸腺淋巴瘤kras基因蛋白表达水平也高于正常胸腺组织。结果提示，kras基因与辐射诱发小鼠胸腺淋巴瘤密切相关，可能是辐射致癌的一种易感基因。

英文摘要：

In order to investigate the relation between kras gene and thymic lymphomas of mice induced by X-rays, we made the thymic lymphomas model of BALB/c mice exposed to X-rays, so as to extracte total RNA and synthesize cDNA and total protein from both of thymic lymphomas and normal thymus tissue. The mRNA and pro- tein expression of kras gene in thymic lymphomas and normal thymus were detected by QRT-PCR and Western blot, respectively. The results show that mRNA expression of kras gene in thyrnic lymphomas （2.66 ~ 1.51） is significantly higher （p〈0.05） than that of normal thymus tissue （0.93：~0.30）; and protein expression of kras gene in thymic lym- phomas is higher than that of normal thymus tissue. The results suggest that kras gene might be relative to thymic lymphomas induced by X-rays, and it might be a susceptibility gene to radiation carcinogenesis.