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Updated: Jun 6, 2026

Circadian Entrainment of Drosophila Melanogaster
Published on: June 3, 2020
A circadian rhythm sleep disorder: melatonin resets the biological clock
1Department of Clinical Biochemistry, Good Hope Hospital, Heart of England NHS Foundation Trust, Sutton Coldfield, West Midlands B75 7RR, UK.
Abstract:
Circadian rhythm sleep disorders are poorly understood and often misdiagnosed. They are all related to the timing of sleep within the 24-hour day. This paper describes a patient with a long history of sleep disturbance whom we diagnosed as having delayed sleep phase syndrome by history and measurement of urinary melatonin metabolite excretion. Literature on the characteristics, diagnosis and management of this syndrome are briefly reviewed. In addition, the relation of the neurohormone melatonin to circadian rhythm and its other physiological roles are described.
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