2259
Due to defective chloride channels ( CFTR ) , the concentration of chloride in sweat is elevated in individuals with CF. Background Cystic fibrosis is caused by defects in a protein found in many tissues , including the airways and the sweat gland s. As a result , these tissues do not work properly .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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