1727
We challenge each of 55 consecutive ragweed ( RW ) - allergic patients with hay fever and with graded increasing doses of ragweed extract to investigate the frequency and relationship between the early ( ER ) , late ( LPR ) , and rechallenge reactions ( RCRs ) to nasal challenge .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
Answer:
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