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本研究以γ线不同方式照射猕猴,对所诱发的染色体畸变进行了比较研究。一次急性照射的剂量率为223 mGy/min;分次累积照射的剂量率为223 mGy/min,每次照射0.25 Gy,每周照射一次;慢性连续照射以0.26 mGy/min的剂量率,每天照射190分钟,每周连续照射5天,总累积剂量均为2.0 Gy。实验结果发现,一次急性照射的主要畸变类型为双着丝点体和无着丝点断片,分次累积照射和慢性连续照射则以无着丝点断片为主。各照射组动物的染色体畸变率都随着照射剂量的增加而呈线性增高,其中一次急性照射组的染色体损伤比其他两组的要严重得多,但后两组之间却无明显差异,且当累积剂量达到1.0Gy以上时,后两组的无着丝点断片率随着累积剂量的增大而升高缓慢。停照后一年内染色体畸变率基本上降到对照水平。
In this study, different ways of γ-ray irradiation of macaques, the induced chromosome aberrations were compared. The dose rate of one acute exposure was 223 mGy / min. The dose rate of cumulative irradiation was 223 mGy / min, with 0.25 Gy irradiation once a week. Chronic continuous irradiation dose rate of 0.26 mGy / min was applied daily 190 minutes, continuous irradiation for 5 days a week, the total cumulative dose of 2.0 Gy. The experimental results showed that the main types of distortions in a single acute irradiation were dicentric dots and no centromere fragments, while the fractional cumulative irradiations and chronic continuous irradiation were dominated by no centromere fragments. The chromosome aberration rate of each irradiated group increased linearly with the increase of irradiation dose. The chromosomal damage of one acute irradiation group was much more serious than the other two groups, but there was no significant difference between the latter two groups When the cumulative dose reached more than 1.0Gy, the last two groups of no-filament fragment rate increased slowly with increasing cumulative dose. Chromosome aberration rate within one year after the stop of the irradiation basically dropped to the control level.