7744
Time - activity curves from the gastric region of interest were used , after subjection to appropriate corrective procedures , to calculate the mean gastric transit time ( MTT 90 ) and the fraction of the test meal retained in the stomach after 90 min ( F90 ) .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
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