7779
At the lowest concentration , effects were mainly observed after 24 h of exposure , with over - transcription of cor , hsp40 , rxr , and sod , whereas higher concentrations down - regulated the expression of most of the studied transcripts , especially after 48 h of exposure .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
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