23442
The outcome of this study indicates that mouse PCLS are a valuable tool in research on hepatic functions and toxicity , particularly if they are cultured under a controlled oxygen concentration of 80 % .
 Chemical: oxygen
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