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Challenges engendered by this lack of information is further amplified by inter - and intraspecies differences in the specificity and affinity of substrates and inhibitors , prohibiting a simple extrapolation of probe substances used in human CYP research .
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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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