Funding for this research was provided by:
Grants-in-Aid for Scientific Research (221S0003)
Grant-in-Aid for Scientific Research (24300133)
Text and Data Mining valid from 2019-03-28
Received: 3 March 2019
Accepted: 16 March 2019
First Online: 28 March 2019
Ethics approval and consent to participate
: This study was approved by the ethics committee of Tokyo Metropolitan Institute of Gerontology (No. 3589).
: Informed consent was obtained from the patients’ families.
: The authors declare that they have no competing interests.
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