4614
Here , we studied whether antagonizing the Fas receptor ( FasR ) pathway by small - interfering RNA ( siRNA ) applied after SM exposure would prevent apoptosis and , thus , airway injury .
 None
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 None