title: Letter: "Ankylosing rheumatoid arthritis", ankylosing spondylitis, and HL-A antigens.
mesh_terms: D001172:Arthritis, Rheumatoid / Q000175:diagnosis / Q000276:immunology*; D003937:Diagnosis, Differential; D000939:Epitopes; D006649:Histocompatibility Antigens / Q000302:isolation & purification*; D006801:Humans; D013167:Spondylitis, Ankylosing / Q000175:diagnosis / Q000276:immunology*
chemical_list: D000939:Epitopes; D006649:Histocompatibility Antigens