Protein expression patterns and metal metabolites in a protogynous hermaphrodite fish, the ricefield eel (Monopterus albus) oleh Zhi He, Feng Xiao, Deying Yang, Faqiang Deng, Wenxiang Ding, Zhide He, Siqi Wang, Qiqi Chen, Haochen Wang, Mingqiang Chen, Kuo Gao, Jinxing Xiong, Ziting Tang, Mingwang Zhang, Taiming Yan