Carnes B A, Fritz T E
Center for Mechanistic Biology and Biotechnology, Argonne National Laboratory, Illinois 60439.
Radiat Res. 1993 Oct;136(1):103-10.
The effects of exposure to 60Co gamma rays for the duration of life on mortality patterns in beagles were investigated. Doses of 3, 7.5, 18.8, 37.5, 75, 127.5, 262.5, 375, or 540 mGy were delivered over a 22-h day 7 days a week. Hazard models with time-dependent covariates were used to identify radiation-related trends in mortality. Hematopoietic failure occurring early in life was positively associated with the accumulated dose and the rate at which the dose was delivered. The risk of death from causes other than cancer that occurred later in the life span also depended on accumulating dose and dose rate but was lower than the cancer risk. Once an animal survived long enough to die from cancer, failure times depended only on the accumulating dose. The slope 1 and slope 2 boundary in a Gompertz plot historically used to identify the transition between dose rate and total dose effects was also found to distinguish between late-occurring deaths associated with tumor or nontumor events.
研究了终生暴露于60Coγ射线对比格犬死亡模式的影响。每周7天、每天22小时给予3、7.5、18.8、37.5、75、127.5、262.5、375或540 mGy的剂量。使用具有时间依赖性协变量的风险模型来确定死亡率中与辐射相关的趋势。生命早期发生的造血功能衰竭与累积剂量和剂量给予速率呈正相关。生命后期发生的非癌症原因导致的死亡风险也取决于累积剂量和剂量率，但低于癌症风险。一旦动物存活足够长时间死于癌症，失效时间仅取决于累积剂量。历史上用于识别剂量率和总剂量效应之间转变的Gompertz图中的斜率1和斜率2边界，也被发现可区分与肿瘤或非肿瘤事件相关的晚期死亡。
