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Introduction : Genetic , physiological , and biochemical data indicate that agglomerates of the 42 - amino acid form of the amyloid - beta ( A beta 42 ) peptide are strongly linked to Alzheimer ' s disease ( AD ) etiology and thus represent a particularly attractive target for the development of an effective disease - modifying approach for AD treatment .
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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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