3520
Pluripotent stem cells evade replicative senescence , whereas other primary cells lose their proliferation and differentiation potential after a limited number of cell divisions , and this is accompanied by specific senescence - associated DNA methylation ( SA - DNAm ) changes .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
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