6032
Transcription levels at the ORC1 sites directly correlated with replication timing , suggesting the existence of two classes of ORIs : those associated with moderate / high transcription levels ( >= 1 RNA copy / cell ) , firing in early S and mapping to the TSSs of coding RNAs ; and those associated with low transcription levels ( < 1 RNA copy / cell ) , firing throughout the entire S and mapping to TSSs of ncRNAs .
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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:
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