599
For this study , 20 individuals ( mean age 39 . 5 + / - 11 . 1 years ) with long - standing type 1 diabetes ( 21 . 3 + / - 10 . 7 years ) were enrolled in this prospective open - label crossover trial .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Anatomy 
Text: {0} 
Answer:
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