１８９５年伦琴发现了Ｘ射线，开创了Ｘ线检查的新纪元，随着Ｘ线检查的广泛应用和不断发展，放射防护这个问题也日益引起了人们的高度重视。１放射防护的意义Ｘ线穿过人体将产生一定的生物效应。若所用Ｘ线量过多，超过容许的曝射量，就可能产生放射反应，甚至产生放射损... Roentgen discovered X-ray in 1895 and started a new era of X-ray examination. With the extensive application and continuous development of X-ray examination, the issue of radiation protection has drawn increasing attention. 1 Radiation Protection X-ray through the human body will have a certain biological effects. If the amount of X-ray used is too large, more than the allowable exposure, radiation reaction may occur, or even produce radiation loss ...