2
Resistance to the simulated physiologic environment was tested by measured retention of mechanical properties after immersion times in pseudo - extracellular fluid ( PECF ) at 37 degrees C for as long as three years .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
Answer:
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