Lloyd R D, Taylor G N, Angus W, Miller S C
Radiobiology Laboratory, University of Utah, Salt Lake City 84112.
Health Phys. 1995 Feb;68(2):225-33. doi: 10.1097/00004032-199502000-00008.
The occurrence of soft tissue tumors has been studied in 117 beagles assigned to 8 dosage groups of between 2 and 26 animals each and injected with 0.07 to 104 kBq 241Am kg-1 as the citrate. In addition, 133 control beagles given no radioactivity were used as a comparison group. All 250 dogs were maintained under identical conditions and were observed for their entire lifespans. An important competing risk for the appearance of soft tissue tumors appeared to be the occurrence of skeletal malignancy, and at the highest injected activity (104 kBq kg-1), kidney and liver failure brought about the death of both of the two dogs in this group. Thyroid and liver were the only soft tissues that exhibited greater concentrations of 241Am than the skeleton. Liver tumors were associated with 241Am exposure (p < 0.001), but the thyroid tumor rate was not increased significantly in the irradiated animals (p > 0.10) as compared with the occurrence in controls. There was a greater relative occurrence of all vaginal tumors in control animals than in dogs given 241Am, a situation also found for all tumors of the pancreas, skin, testis, and mammary glands and for malignant ovarian tumors. All of these differences were statistically significant. The survival of animals given 0.07 to 0.59 kBq 241Am kg-1 could not be established (p > 0.10) as significantly different from controls, but the survival of all groups given 1.8 to 104 kBq kg-1 was decreased (p < 0.05). There was no indication in our studies of a positive association between relative exposure to 241Am and the occurrence of mammary tumors, mast cell sarcomas originating outside the liver, lymphosarcoma or tumors of marrow, including leukemia.
对117只比格犬进行了软组织肿瘤发生情况的研究，这些比格犬被分为8个剂量组，每组2至26只动物，每千克体重注射0.07至104 kBq的241Am柠檬酸盐。此外，将133只未接受放射性物质的对照比格犬作为对照组。所有250只狗都在相同条件下饲养，并对其整个寿命进行观察。软组织肿瘤出现的一个重要竞争风险似乎是骨骼恶性肿瘤的发生，在最高注射活性（104 kBq/kg）时，该组两只狗均因肾衰竭和肝功能衰竭死亡。甲状腺和肝脏是仅有的软组织中241Am浓度高于骨骼的组织。肝脏肿瘤与241Am暴露有关（p<0.001），但与对照组相比，受辐照动物的甲状腺肿瘤发生率没有显著增加（p>0.10）。对照动物中所有阴道肿瘤的相对发生率高于接受241Am的狗，胰腺、皮肤、睾丸、乳腺的所有肿瘤以及卵巢恶性肿瘤也有这种情况。所有这些差异均具有统计学意义。无法确定每千克体重注射0.07至0.59 kBq 241Am的动物的存活率与对照组有显著差异（p>0.10），但每千克体重注射1.8至104 kBq的所有组的存活率均降低（p<0.05）。我们的研究未表明241Am相对暴露与乳腺肿瘤、肝脏外起源的肥大细胞肉瘤、淋巴肉瘤或包括白血病在内的骨髓肿瘤的发生之间存在正相关。
