Adult, Aged, Aged, 80 and over, Arthritis, Rheumatoid, DNA Nucleotidylexotransferase, Female, Gene Expression Regulation, Gene Rearrangement, Genes, Immunoglobulin, Humans, Immunoglobulin kappa-Chains, Male, Middle Aged, Polymerase Chain Reaction, Recombination, Genetic, Synovial Membrane