Lloyd R D, Angus W, Taylor G N, Miller S C
University of Utah, Salt Lake City 84112, USA.
Health Phys. 1995 Aug;69(2):272-7. doi: 10.1097/00004032-199508000-00014.
The occurrence of soft-tissue tumors in beagles given 90Sr (88 dogs), 228Ra (76 dogs), or 228Th (81 dogs) as young adults and followed throughout their lifespans was compared with that of 133 control beagles given no radioactivity. For animals injected with 228Ra, tumors of the eye were more prominent (p < 0.05) than in the controls, and soft-tissue tumors of cavities in the head (excluding the brain, mouth, and eye) were more prominent in dogs given 90Sr than in the controls (p < 0.05). There was some indication that eye tumors in animals given about 0.56 kBq 228Th kg-1 were associated with their radionuclide exposure. For tumors at a few other locations, the relative occurrence was greater (p < 0.05) in the controls. These included malignant tumors of the testis and malignant plus benign tumors of the mammae and vagina in 228Th dogs; both malignant and malignant plus benign tumors of the mouth and testis, and malignant plus benign tumors of the mammae and vagina in 228Ra dogs; and malignant plus benign tumors of the mammae in 90Sr dogs (p > 0.05 by Odds Ratio Chi Square analysis but p < 0.05 by Fisher's Exact Test). Differences in relative occurrence between radioactive dogs and controls of all other tumor types that appeared in any of the animals (notably lymphosarcoma, lymph node tumors, leukemia, mast cell tumors, liver tumors, etc.) were not statistically significant (p > 0.05). Intercurrent mortality, mainly from bone cancer, was higher in the radioactive dogs than in the controls. Mean survival was reduced in the dogs given 90Sr, 228Ra, or 228Th (13.17 +/- 2.64 y in controls, 10.95 +/- 4.06 y in 90Sr dogs, 9.07 +/- 3.61 y in 228Ra dogs, and 9.20 +/- 4.15 y in 228Th dogs). Attenuated lifespans could account, at least in part, for the relative paucity of soft-tissue tumors not induced by radiation among the groups of dogs given radioactivity and occurring near the end of life for control animals.
将成年初期的比格犬分别给予90Sr（88只犬）、228Ra（76只犬）或228Th（81只犬）并跟踪其一生，比较这些犬软组织肿瘤的发生情况与133只未接受放射性物质的对照比格犬的情况。对于注射了228Ra的动物，眼部肿瘤比对照组更突出（p<0.05），而给予90Sr的犬头部腔隙（不包括脑、口和眼）的软组织肿瘤比对照组更突出（p<0.05）。有迹象表明，给予约0.56 kBq 228Th kg-1的动物眼部肿瘤与其放射性核素暴露有关。对于其他一些部位的肿瘤，对照组的相对发生率更高（p<0.05）。这些包括228Th犬的睾丸恶性肿瘤以及乳腺和阴道的恶性加良性肿瘤；228Ra犬的口和睾丸的恶性及恶性加良性肿瘤，以及乳腺和阴道的恶性加良性肿瘤；以及90Sr犬的乳腺恶性加良性肿瘤（优势比卡方分析p>0.05，但费舍尔精确检验p<0.05）。在所有接受放射性物质的犬组中出现的、与对照组相比的所有其他肿瘤类型（特别是淋巴肉瘤、淋巴结肿瘤、白血病、肥大细胞瘤、肝肿瘤等）的相对发生率差异无统计学意义（p>0.05）。放射性犬的并发死亡率主要源于骨癌，高于对照组。给予90Sr、228Ra或228Th的犬平均生存期缩短（对照组为13.17±2.64年，90Sr犬为10.95±4.06年，228Ra犬为9.07±3.61年，228Th犬为9.20±4.15年）。寿命缩短至少可以部分解释在给予放射性物质的犬组中以及对照动物接近生命末期时未由辐射诱发的软组织肿瘤相对较少的原因。
