Figure 1.

Antiviral activity of BA in treating A/PR/8/34-infected mice. Mice were inoculated with virus intranasally and treated with BA at the indicated concentration every 24 h for 14 days. Each group consists of 10 mice. (a) Survival rate of mice was observed in the next two weeks. ▲: untreated mice; ●: control A/PR/8/34-infected mice; ∆: 1.0 g/kg BA-treated mice; ○: 1.5 g/kg BA-treated mice; □: 2.0 g/kg BA-treated mice. (b) Lungs of mice were homogenized separately, diluted, and centrifuged on the third, fifth, and seventh day after infection, and the EID₅₀s were determined using 10-day chick embryo. (c) Lungs of mice were removed and examined pathologically using HE staining on the seventh day after infection. ^#Levels of significance of P < 0.05 against untreated mice; ^∗P < 0.05  against control infected mice; ^∗∗P < 0.01 against control infected mice.