title: Strain-differentiated circadian and ultradian rhythms in locomotor activity of the laboratory rat.
mesh_terms: D000204:Activity Cycles; D000818:Animals; D002940:Circadian Rhythm; D003624:Darkness; D008027:Light; D008124:Locomotion; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains / Q000502:physiology*; D013045:Species Specificity; D013057:Spectrum Analysis