20912
Apart from the above - mentioned models of negative and cognitive symptoms , MK - 801 and amphetamine - induced hyperactivity tests , plus the DOI - induced head twitches in mice as models for positive symptoms of psychosis , were used in this part of the investigations .
 Chemical: MK - 801; Chemical: amphetamine; Chemical: DOI
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: MK - 801; Chemical: amphetamine; Chemical: DOI