@article{oai:repo.qst.go.jp:00043164,
 author = {Takeda, Hiroshi and Fuma, Shoichi and Miyamoto, Kiriko and Kuroda, Noriko and Inaba, Jiro and 武田 洋 and 府馬 正一 and 宮本 霧子 and 黒田 典子},
 journal = {Radiation Protection Dosimetry},
 month = {},
 note = {The transfer of C14 through placenta or milk was investigated and the radiation dose to fetal and newborn rats was estimated. Female rats at different gestational stages or after delivery ware exposed to C14 in the form of sodium bicarbonate, thymidine and lysine by a single ingestion. Radioactivity in maternal tissues and conceptuses (placenta, fetal membrane and fetus) and in the newborn was determined at various times after ingestion. After exposure to these C14 compounds, there was no significant difference between the C14 concentration in the fetus and that in the maternal tissues, suggesting that the placenta has no effect in preventing or accelerating the placental transfer of C14. The concentration and content of C14 in the fetus and newborn were, however, dependent on the chemical form of C14 and on the prenatal or neonatal stage at the time of ingestion. The result of the does estimation showed that C14-lysine gave significantly higher prenatal and neonatal doses than C14-sodium bicarbonate or C14-thymidine.},
 pages = {291--296},
 title = {Transfer of carbon-14 to prenatal and neonatal rats from their mothers exposed to 14C-compounds by ingestion},
 volume = {105},
 year = {2003}
}