Serum levels of erythropoietin in rheumatoid arthritis.
D000740:Anemia / Q000150:complications; D000747:Anemia, Hypochromic; D001172:Arthritis, Rheumatoid / Q000097:blood*; D004921:Erythropoietin / Q000097:blood*; D006400:Hematocrit; D006801:Humans; D009500:Neutralization Tests
D004921:Erythropoietin