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. 2022 Feb 7;12:723424. doi: 10.3389/fneur.2021.723424

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Copyright © 2022 He, Li, Qiu, Jin and Ma.

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Flow diagram depicting the selection process of eligible studies. CNKI, China national knowledge infrastructure; VIP, Chinese Scientific Journals Database; SinoMed, Chinese Biomedical Literature Service System; n, number of publications.