15815
Hypoxia elicits a variety of complex cellular responses by altering the activity of many signaling pathways , such as the oxygen - dependent prolyl - hyroxylase domain - containing enzyme ( PHD ) .
 Chemical: oxygen; Chemical: prolyl
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: oxygen; Chemical: prolyl