chromosome studies were performed on peripheral blood lymphocytes of 28 patients with connective tissue disease ( 6 with progressive systemic sclerosis , 6 with systemic lupus erythematosus , 6 with anti-nuclear antibody positive rheumatoid arthritis , 6 with anti-nuclear antibody negative rheumatoid arthritis , and 4 with mixed connective tissue disease ) and on 17 controls to determine the frequency of spontaneous as well as x-ray ( 75 rads ) induced aberrations .
C0009782
connective tissue disease
C0036421
progressive systemic sclerosis