Fig. 5.
Correlations between the concentration of nitrate (NO3−)and nitrite (NO2−) to the concentration of polymorphonuclear leucocytes (PMNs) in sputum from cystic fibrosis (CF) patients with chronic Pseudomonas aeruginosa lung infection. The concentrations of NO3− and NO2− were determined by the Griess reagent system and the concentration of PMNs was estimated by flow cytometry. (a) NO3− concentration versus the concentration of PMNs (P < 0·04, n = 10). (b) NO2− concentration versus the concentration of PMNs (P < 0·006, n = 11). Statistical analysis was performed by Spearman's rank correlation test.