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From 1986 to February 1993 , 40 children aged 2 months to 18 years ( average age 10 . 4 + / - 5 . 8 years ) underwent heart transplantation .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Disease, Chemical 
Text: {0} 
Answer:
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