3067
Groups of male and female Fischer 344 rats , B6C3F1 mice , and Hartley guinea pigs were exposed once for 6 hr to mean concentrations of 10 . 5 , 5 . 4 , 2 . 4 , 1 . 0 , or 0 ( control ) ppm of methyl isocyanate ( MIC ) vapor .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
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