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Gao Y, Chen J, Wang GQ, Li YK, Bian CR.Gao Y, et al.Shanghai Kou Qiang Yi Xue. 2021 Oct;30(5):481-487.Shanghai Kou Qiang Yi Xue. 2021.PMID: 34888599Chinese.
Zhang DS, Bian CR, Wang PY, Yuan XL, Wang JY.Zhang DS, et al.Shanghai Kou Qiang Yi Xue. 2004 Oct;13(5):396-8.Shanghai Kou Qiang Yi Xue. 2004.PMID: 15514865Chinese.