Protein content in bronchoalveolar lavage fluid with and without exposure to smoke and mechanical ventilation. Mechanical ventilation plus smoke exposure (S-V) led to significant increases in bronchiolar lavage (BAL) fluid protein content compared to normal controls (P < 0.01). Even though the P-value is less than 0.01, the addition of cigarette smoke exposure to ventilated rats did not lead to a significant further increase of BAL protein content after correction for false discovery rate (NSV vs. SV). The bars to the right of the data points indicate means ± SD. NS-NV: nonsmoke/nonventilated; NS-V: Ventilation alone; S-NV: Smoke/nonventilated.