Respiratory resistance Rrs5 and Rrs20 were higher and reactance Xrs5 more negative in patients than in normal subjects (Rrs5: 0.332 ± 0.065kPa / L / s, Rrs20: 0.251 ± 0.078kPa / L / s, Xrs5: - 0.0061 ± 0.0012kPa/L/s).