22778
Comparative pharmacokinetics of N ( omega ) - hydroxy - nor - L - arginine , an arginase inhibitor , after single - dose intravenous , intraperitoneal and intratracheal administration to brown Norway rats .
 N ( omega ) - hydroxy - nor - L - arginine
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 N ( omega ) - hydroxy - nor - L - arginine