The numbers of NF-κB+ cells in peribronchovascular areas (A) and the NF-κB gene expression levels in bronchiolar epithelial cells (B) obtained for the Control groups after 1 (n = 10 and 5, respectively), 3 (n = 6 and 5, respectively), and 6 (n = 7 and 4, respectively) months and the Smoke groups after 1 (n = 8 and 5, respectively), 3 (n = 5 and 4, respectively), and 6 (n = 10 and 4, respectively) months are presented as the means ± SDs. (A) Significant differences were found after 1 (*P = 0.0025, t-test), 3 (*P = 0.0001, t-test), and 6 (*P = 0.0025, t-test) months. (B) Significant differences were found after 3 (*P = 0.0001, Mann-Whitney test) and 6 (*P = 0.0357, Mann-Whitney test) months. (C) Representative photomicrographs of NF-κB+ cells in peribronchovascular areas are shown at 200× magnification, and images at 1000× magnification are shown in each insert.