[Investigation of the present management status of calibration source based on the law concerning prevention of radiation hazards due to radioisotopes].

An amendment concerning the enforcement of the law on the prevention of radiation hazards due to radioisotopes, etc., and the medical service law enforcement regulations were promulgated on June 1, 2005. This amendment concerned international basic safety standards and the sealing of radiation sources.

[Present status and issues regarding X-ray medical checkup vehicles in preventive medicine: usefulness of mass screening for lung cancer by an X-ray medical checkup vehicle].

Although the prevention of habituation-related diseases has become an important topic in Japan, the early detection of cancers such as lung, gastric, and breast cancers is an important issue for X-ray-related imaging modalities. High cost-benefit and cost-effectiveness are necessary to perform mass screenings such as those for lung cancer. In order to assess cost-benefit and cost-effectiveness, a total of 100 institutions nationwide were investigated, with a 41% of recovery rate.