24964
Conclusion : Our results support the hypothesis that ABCB1 and possibly other ABC - transporters are involved in the process of A beta accumulation in the aging brain and may modulate the risk for AD in an allele - specific manner , and thus might represent a new target for prevention and treatment of AD .
 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