Text and Data Mining valid from 2019-03-11
Received: 11 September 2018
Accepted: 21 January 2019
First Online: 11 March 2019
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: This is a general review of published data; no patients were involved in the conduct of this review.
: Kyeong Tae Kim, Mi Young Eo, Truc Thi Hoang Nguyen, and Soung Min Kim declare that they have no competing interests.
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