© 2020 Ka-Huen Yip, Yuk-Chiu Yip, Catherine Man-Yin Lee, Mei-Yi Siu, Shu-Ying Ngai, Mei-Kuen Chow, published by Shanxi Medical Periodical PressThis work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.