14793
The Michaelis - Menten constant ( Km ) values of hepatic microsomal metabolism were 7 . 23 and 0 . 41 mu M in rats and dogs in vitro , respectively , which were lower than the unbound maximum plasma concentrations after oral administration in vivo , indicating that the nonlinear PK in rats and dogs was attributable to the saturation of hepatic metabolism .
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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:
 None