15697
The TUNEL assay showed that the number of apoptotic cells increased at 8 h , reached a maximum level at 12 h , and then decreased progressively .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities:  
Answer:
 None