4159
Thirty - six patients ( 29 females , 7 males ; mean age 51 years ; range 40 to 69 years ) with type II SIS were randomized to two groups to receive intermittent ultrasound ( group 1 , n = 20 ) and placebo ultrasound ( group 2 , n = 16 ) for three weeks ( 15 sessions ) .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Anatomy 
Text: {0} 
Answer:
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