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In addition , several important genes such as p38 MAPK , antioxidant - related genes , Hsps , and apoptosis - related genes were significantly modulated by copper exposure .
 Chemical: copper
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: copper