4825
A randomized , double-blinded , placebo-controlled study found that a Chinese herbal formula that mainly consisted of Cornus officinalis was not only effective at improving erectile function , but it was also safe for the treatment of erectile dysfunction .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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