Thomas J. Van't Hof

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In passerine birds, the periodic secretion of melatonin by the pineal organ represents an important component of the pacemaker that controls overt circadian functions. The daily phase of low melatonin secretion generally coincides with the phase of intense activity, but the precise relationship between the melatonin and the behavioral rhythms has not been(More)
We examined levels of melatonin in the pineal, eyes and plasma over a 24 h period during development in the altricial zebra finch. Beginning as early as 2 days after hatching there was a distinct 24 h rhythm in melatonin in the pineal and plasma. Beginning at day seven after hatching there was also a 24 h rhythm present in the eyes. In the pineal and eyes(More)
Naturwissenschaften 85 (1998) Q Springer-Verlag 1998 18. Lester BM, Boukydis CFZ (1985) Infant crying, theoretical and research perspectives. Plenum, New York 19. Lockwood WB (1982) Indogermanische Sprachwissenschaft, eine historisch-vergleichende Untersuchung. Narr, Tübingen 20. Lüdge W, Gips P (1989) Microcomputeraided studies of cry jitter uttered by(More)
We have investigated the effect of continuous light and darkness on plasma levels of melatonin in relation to the extremely large and active pineal gland typically found in newborn seals. Plasma levels of melatonin in captive newborn harp (Phoca groenlandica) and hooded seals (Cystophora cristata) were generally extremely high, with peak concentrations(More)
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