20644
Preliminary screening of the compounds involved scavenging hydroxyl radicals and 2 , 2 - diphenyl - 1 - picrylhydrazyl ( DPPH ( . ) ) , croton oil - induced ear edema in mice , and analysis of the mRNA expression of adhesion molecules in ECs .
 Chemical: hydroxyl; Chemical: 2 , 2 - diphenyl - 1 - picrylhydrazyl; Chemical: DPPH ( . )
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: hydroxyl; Chemical: 2 , 2 - diphenyl - 1 - picrylhydrazyl; Chemical: DPPH ( . )