GCH/M index (the number of goblet cells per mm in bronchial epithelia) was detected by sequential alcian blue (AB) and periodic acid-Schiff (PAS) staining of airway tissue.

• 病理切片行HE染色和AB-PAS染色,测定杯状细胞化生/增生(GCH/M)指数(每毫米支气管上皮中杯状细胞数目);