Figure 1.

Urinary excretion of NOx. Consecutive 24-hour urine samples were collected from 25 patients with active rheumatoid arthritis (RA) and 20 healthy controls (N) who were receiving a diet low in nitrate and nitrite. During each of the time periods, no statistically significant differences were observed between the two groups in 24-hour urinary excretion of NOx. Values are expressed as medians (horizontal lines), means (filled circles), interquartile ranges (boxes), and 10th to 90th centile ranges (whiskers). NOx, NO₂^- (nitrite) + NO₃^- (nitrate).