Correlations between HVR and REDST.

Each point represents one subject (●, NAC; ○, placebo group). Shown are regression functions when P < .05 and the coefficients of correlation and P values for the total group and the NAC group. Correlations of the poikilocapnic HVR at 3:30pm on day 6 with the corresponding plasma thiol level and REDST at 3:30 pm are shown in panels A and B, respectively. Panels C and D show the corresponding correlations of the poikilocapnic HVR at 3:30 pm with the mean thiol level or the mean REDST of day 6, respectively (n = 6).