title: Levels of IgG1 - IgG4 subclasses in serum and synovial fluid in rheumatoid arthritis and reactive synovitis of local origin.
mesh_terms: D001172:Arthritis, Rheumatoid / Q000276:immunology*; D006801:Humans; D007128:Immunoglobulin Fragments / Q000032:analysis; D007074:Immunoglobulin G / Q000032:analysis*; D013582:Synovial Fluid / Q000276:immunology
chemical_list: D007128:Immunoglobulin Fragments; D007074:Immunoglobulin G