Viability losses in RAW 264.7 cells induced by 1 μg/ml lipopolysaccharide for different time periods. Survival was monitored daily for 2 days. The magnitude of cell injury peaked at 24 h after lipopolysaccharide exposure. Values were analyzed using the Mann–Whitney U test with Bonferroni correction for five individual experiments. Of note, the predefined significance level (P < 0.05) was reset as P value less than 0.005 after correction. Significant differences were indicated with an asterisk (*P < 0.005).