16996
Moreover , well - established drugs , such as angiotensin - converting enzyme inhibitors ( ACEI ) , angiotensin receptor blockers ( ARB ) , or beta - blockers , show that their mechanism of action may be the result of parallel pathways other than the ones initially established .
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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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