title: Letter: Semen and hepatitis B antigen.
mesh_terms: D005260:Female; D006506:Hepatitis A / Q000235:genetics; D006511:Hepatitis B Antigens / Q000032:analysis*; D006801:Humans; D008297:Male; D011863:Radioimmunoassay; D012661:Semen / Q000276:immunology*
chemical_list: D006511:Hepatitis B Antigens