556
During the observation period of 0 . 4 - 30 weeks , cardiac white spots on the right ventricle of BALB / c mice were first detected at three weeks ( 6 of 20 mice ; 30 % ) , and the maximal incidence of cardiac white spots was obtained at nine weeks ( 39 of 44 mice ; 88 % ) .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
Answer:
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