Iron and zinc are two kinds of indispensable trace elements of fish.

铁和锌是鱼类非常重要的两种必需微量元素。

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Cu, Zn, Co and Ni are indispensable trace elements in human body, which are all transition elements. They serve as important active sites of enzymes, and have good antibacterial activities.

铜、锌、钴、镍是过渡元素，是人体中不可缺少的微量元素，是一些重要酶的活性中心，且均有良好的抑菌活性。

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