6778
Behavioral studies of chronic CB ( 1 ) receptor activation may provide a pharmacological approach to understanding efficacy - related differences among CB ( 1 ) ligands as well as mechanistic commonalities between cannabinoid and noncannabinoid drugs .
 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