3777
Concretely , TOPPR supports three ways to retrieve data : ( i ) the retrieval of all substrates for one or more cellular stimuli or assays ; ( ii ) a substrate search by UniProtKB / Swiss - Prot accession number , entry name or description ; and ( iii ) a motif search that retrieves substrates matching a user - defined protease specificity profile .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
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