5225
For each particle type , three different doses , namely 4 x 100 , 4 x 250 or 4 x 500 mu g / mouse , were used and for each dose , four groups of mice , i . e . group saline solution ( 1 ) , OVA ( 2 ) , particles ( 3 ) , and OVA plus particles ( 4 ) , were constituted .
 None
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 None