3748
Control rats received halothane anesthesia ( 1 MAC ) for one hour , followed by SNP infusion , 40 microgram / kg / min , for 30 min , followed by a 30 - min recovery period .
 Chemical: halothane; Chemical: SNP
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Disease, Chemical 
Text: {0} 
 Entities: halothane, SNP 
Answer:
 Chemical: halothane; Chemical: SNP