To study the effect of ionizing radiation on thyroid glands, 66 Japanese Black cattle residing in the restricted area of the Fukushima Daiichi Nuclear Power Plant in 2013-2017 were pathologically examined. There were no clinical symptoms of thyroid disease in these cattle. Three cases of goiter and seven of atrophy were found in two among the four farms examined. Cases of goiter exhibited normal morphological structure without mass or nodule formation in thyroid glands. Cellular atypia or capsular invasion of the follicular epithelium was absent. The estimated integrated dose of external radiation in goiter cases ranged from maximum 797 mSv to minimum 24 mSv. All lobules in the seven atrophic thyroid glands were affected, but pathological findings, such as inflammatory cell infiltration or stromal fibrosis, were not observed. The estimated integrated dose of external radiation in atrophic thyroids ranged from maximum 589 mSv to minimum 8 mSv. Immunohistochemical analysis of anti-nitroguanosine and the TUNEL method in goiter and atrophic thyroid glands did not reveal any positive findings. The present study indicates that there was no significant relationship between a radiation effect and pathological findings in any thyroid glands.

中文翻译：

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在福岛第一核电站事故禁区居住的日本黑牛甲状腺的病理特征。

为了研究电离辐射对甲状腺的影响，对2013-2017年福岛第一核电站禁区内居住的66头日本黑牛进行了病理检查。这些牛没有甲状腺疾病的临床症状。在所检查的四个农场中，有两个发现了3例甲状腺肿和7个萎缩。甲状腺肿病例表现出正常的形态结构，在甲状腺中没有肿块或结节形成。缺乏滤泡上皮细胞的异型性或荚膜浸润。甲状腺肿病例中估计的外部辐射综合剂量范围从最大797 mSv到最小24 mSv。七个萎缩性甲状腺的所有小叶均受到影响，但未观察到病理学发现，例如炎性细胞浸润或基质纤维化。萎缩性甲状腺的外部辐射估计总剂量范围从最大589 mSv到最小8 mSv。甲状腺肿和萎缩性甲状腺中抗硝基鸟嘌呤和TUNEL法的免疫组织化学分析未发现任何阳性结果。本研究表明，在任何甲状腺中，放射线作用与病理结果之间均无显着关系。