4643
These results indicate that ATR exposure differentially modifies the dopaminergic systems , and these modifications may underlie the behavioral changes observed .
 Chemical: ATR
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: ATR 
Answer:
 Chemical: ATR