4279
A combination of [ + ] and [ - ] - Huperzine A improves protection against soman toxicity compared to [ + ] - Huperzine A in guinea pigs .
 Chemical: [ + ] and [ - ] - Huperzine A; Chemical: [ + ] - Huperzine A
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: [ + ] and [ - ] - Huperzine A; Chemical: [ + ] - Huperzine A