Effects of NMB and NMBRA treatments on the expression of virus NP in mice. Lung tissues from treated mice were sampled at 3 dpi. The profiles of NP expression were assayed by RT-PCR, qRT-PCR or Western blotting. Decreased virus NP expression after NMB treatment was observed (A–C); increased virus NP expression induced by NMBRA treatment was confirmed (D–F). β-Actin was used for internal standardization. *P < 0.05.