Yttrium (Yttrium, Y) is an element of the III group of the periodic system of elements of D. I. Mendeleyev. Serial number 39, atomic weight 88,9. Yttrium metal gray.
In medicine have found application Y88, Y90 and Y 91. The greatest practical importance Y90 - pure beta-emitter (see Beta-radiation) with a half-life 64,24 hours. Y90 is formed by radioactive decay of strontium-90 (see Strontium). Y90 used for radiation therapy (see) in the form of applicators and models for surface applications (see Beta-therapy). In the form of needles and samorastekayushchikhsya threads Y90. injected directly into the tumor tissue. When leukemia chloride solution Y90 injected and blood, he goes into the colloidal state.
Cm. also Radioactive drugs.