. 2018 Apr 15;9(4):66–71. doi: 10.4239/wjd.v9.i4.66
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This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial.
Figure 1.
Flow chart implemented for the selection of articles for this review.