title: Virus titrations using trypsin modified erythrocytes.
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000032:analysis*; D001789:Blood Group Antigens; D004912:Erythrocytes / Q000187:drug effects*; D006385:Hemagglutination Inhibition Tests / Q000379:methods*; D006386:Hemagglutination Tests / Q000379:methods*; D014357:Trypsin / Q000494:pharmacology*; D014780:Viruses / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D001789:Blood Group Antigens; D014357:Trypsin