Fig. 5.

Apoptosis of CEP induced by passive smoking. (A) Immunostaining non-smoking (N) and smoking (S) rats for 4 or 8 weeks (eg. N4 or N8) for ssDNA of CEP. Arrows indicate cells containing ssRNA positive brown nuclei (Nakahashi et al., 2019). (B) The positive rate was calculated using the ssDNA positive cells in the CEP. A significant increase can be seen in smokers in both 4 and 8 weeks compared to non-smokers (Nakahashi et al., 2019). (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)