In order to investigate metabolic mechanism of several essential metals in injured mice leading to recovery after irradiation of r-rays with a sublethal dose, mice were exposed to doses of 4 Gy leading to the recovery or 10 Gy leading to death, and injected with their radioactive tracers of54Mn, 58Co, 59Fe and65Zn 24 h later. Then, retention rates of the nuclides in whole body concerning with the elimination and presence rates of the elements in their tissues and organs 7 days post the injection, were measured and compared between these radiation doses, metals and organs. A difference of the retention rates between the doses was observed for58Co and65Zn, and that of the presence rates found also in these elements and organs, particularly for59Fe, a remarkable decreasing in blood and increasing in liver, kidney and bone with doses. Such a difference shows that of metabolisms leading to recovery or death.
An access control system with a personal computer has been developed for radioisotope facility. The developed system is composed of a NEC PC-9801 UX2 personal computer having two of 1 Mbyte floppy-disk drivers and extended random access memory (2 Mbyte), automatic door and two of non-contact identification card scanners (Nippon ID System Inc. ) . The identification card scan-ners are controlled by the personal computer via RS-232C. By the use of the non-contact identification card, user's name and entrance and leaving times are recorded automatically in a file.