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In addition , internalization of TSS - SPIONs into human endothelial progenitor cells ( EPC ) from umbilical cord blood was more than threefold and 17 - fold higher in contrast to UC - SPIONs and SPIONs , respectively .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 None