19390
A number of oxysterols abundant in the SLOS mouse are probably derived from 7 - dehydrocholesterol , however , the mechanism of their formation is unclear .
 Chemical: oxysterols; Chemical: 7 - dehydrocholesterol
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: 7 - dehydrocholesterol