Thus, it indicated that the stimulation of calcium messenger system and accumulation of active oxygen free radical were closely related to fruits maturation and senescence.

表明细胞内钙信使系统的活化和活性氧自由基的积累与果实成熟衰老密切相关。

youdao

A: the autonomic nervous system USES the hormone adrenaline, a neurotransmitter, or chemical messenger, to send signals to various parts of the body to activate the fight-or-flight response.

答：这套自动神经系统利用肾上腺激素(一种神经递质，或者称为化学信使)把信号发送到身体的各个部分，以便激活“斗争还是逃避”反应。

youdao

The autonomic nervous system USES the hormone adrenaline, a neurotransmitter, or chemical messenger, to send signals to various parts of the body to activate the fight-or-flight response.

自身的神经系统利用肾上腺素，一种神经传递介质或者说是化学信使，把信号传递在身体的各个部位以刺激“战或逃反映”。

youdao

Acting as a messenger between the central nervous system and the major organs, the vagus nerve slows the heart rate (through the release of the neurotransmitter acetylcholine), calms the immune response (by controlling the release of proteins called cytokines), and communicates with the muscles that control respiration and digestion.

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The bacteria interacts with a molecule called IL-8 which should act as the messenger to rally other parts of the immune system to attack the "invader".

BBC: NEWS | Health | How the flesh-eating bug attacks

The strain affecting the patient was isolated and grown in the lab, and biochemical analysis found that the bacteria prevented the immune system responding as normal by "shooting the messenger".

BBC: NEWS | Health | How the flesh-eating bug attacks