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The main scientific schools that initiated research on chemistry , enzymology and physiology of cholinesterases and their inhibitors were leaded by Alexandr and Boris Arbuzovs , Victor Rozengart , Viktor Yakovlev , Michael Michelson , Martin Kabachnik , Mikhail Voronkov , Ivan Knunyants , Alexandr Bretskin and others .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
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