氟是机体必需的微量元素之一，氟与人体生命活动及牙齿、骨骼组织代谢密切相关。

Fluorine is one of the essential microelement of human body. There are close correlation in fluorine and human body life activity, tooth and skeleton constitution metabolism.

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氟是机体生命活动所必需的微量元素之一，具有多方面的生理作用。

Fluorine is one of the necessary trace elements for the body and it has many physiological effects.

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化石发掘和微量元素分析表明，热河生物群经历了集群死亡和快速掩埋，火山活动的有毒气体是生物灾难事件的主要因素。

Excavation and trace element analysis indicates: Jehol biota experienced mass mortality and rapid burial; toxic gases of the volcanic activities are the main factors of biological catastrophic event.

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