9143
After measuring baseline Vmca at a partial pressure of carbon dioxide in arterial blood ( PaCO2 ) of 37 . 7 + / - 4 . 5 mmHg ( mean + / - SD ) , measurements were repeated at a PaCO of 44 . 2 + / - 3 . 8 mmHg , and the carbon dioxide reactivity ( absolute value : cm x s ( - 1 ) x mmHg ( - 1 ) ; relative value : percentage of baseline Vmca / mmHg ) was calculated .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
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