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Circulating 25 - hydroxyvitamin D ( 25 - OHD ) levels vary among human populations .
 Chemical: 25 - hydroxyvitamin D; Chemical: 25 - OHD
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: 25 - hydroxyvitamin D; Chemical: 25 - OHD