16669
The rewarding effects of morphine ( 5 mg / kg ) under treatment with ethanol were measured by the conditioned place preference paradigm .
 Chemical: morphine; Chemical: ethanol
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: morphine; Chemical: ethanol