单词	melatonin
释义	melatonin /ˌmɛləˈtəʊnɪn / noun [mass noun] Biochemistry A hormone secreted by the pineal gland which inhibits melanin formation and is thought to be concerned with regulating the reproductive cycle.The pineal gland hormone, melatonin, is one of the endproducts regulated by the circadian system.... Delaying sleep on weekends delays the nightly secretion of melatonin, the sleep hormone. Research has found the pineal hormone melatonin is low in migraine patients. Origin 1950s: from Greek melas 'black' + serotonin.
随便看	Ascalon A-scan A-scanning ASCAP ascariasis ascarid ascaris as-cast ascend ascendancy ascendant ascendency ascendent ascender ascending colon ascend the throne ascension ascensional Ascension Day Ascension Island ascension robe Ascensiontide ascent ascertain ascertainable

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