Intraoperative transcutaneous electrical acupoint stimulation combined with anesthesia to prevent postoperative cognitive dysfunction: A systematic review and meta-analysis - Lin Gan; Kecheng Qian; Jinding Yang; Qian Cai; Qinyu Ye; Mengyuan Dai; Zhaoxing Jia; Tianxiang Jiang; Congcong Ma; Xianming Lin (PLoS ONE, 2025)