19395
The role of oxysterols in cholesterol metabolism and several diseases has been widely investigated , but many questions remain to be answered .
 Chemical: oxysterols; Chemical: cholesterol
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: oxysterols; Chemical: cholesterol