958
Studies with and without attenuating media were performed , and myocardium - to - defect count ratios and defect sizes from dual - isotope SPECT images were compared to myocardium - to - defect count ratios and defect sizes from single - isotope ( 201Tl and 99mTc ) SPECT images .
 None
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
Answer:
 None