7211
The avidities of the VS - Abs to the homologous venoms were 2 . 53 +/- 0 . 4 , 2 . 66 +/- 0 . 31 and 2 . 8 +/- 0 . 06 for Nh , Nn and Wa venoms respectively ; whereas the avidity of the same Abs to the heterologous venoms could hardly exceed 1 .
 None
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 None