in a multicenter cooperative study , sera from 85 patients with active chronic hepatitis ( ach ) were examined for the presence of hepatitis b ( australia ) antigen ( hbag ) by radioimmunoassay ( ria ) and antibody to hbag ( anti-hbag ) by ria and passive hemagglutination ( pha ) , the most sensitive currently available techniques .
C0019168
australia
C0019165
hbag