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B 12,Vitamin

《英文msh詞典》B 12,Vitamin
[入口詞] B 12,Vitamin
[主題詞] Vitamin B 12
[英文釋義] A cobalt-containing coordination compound produced by intestinal micro-organisms and found also in soil and water. Higher plants do not concentrate vitamin B 12 from the soil and so are a poor source of the substance as compared with animal tissues.

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