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Thyroid hormones act by binding to nuclear receptor proteins , the thyroid hormone receptors ( TR ) alpha and beta .
 protein: nuclear receptor proteins; protein: thyroid hormone receptors; protein: TR
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
Answer:
 protein: nuclear receptor proteins; protein: thyroid hormone receptors; protein: TR