Biological clock- our 24 hours’ rhythms

When the human circadian system is caught napping: evidence for endogenous rhythms close to 24 hours.

It is now well acknowledged that napping constitutes an inherent component of the human circadian system. To date, however, few studies have examined the effects of spontaneous napping on human free-running rhythms. This study investigated the free-running circadian periods of rest/activity and body core temperature in a group of young subjects who were permitted to nap during their time in iso...

Genetic clock of biologic rhythms.

Biologic rhythms are tightly regulated in all species, in order to adapt to circadian variations of light, temperature and other biological related living conditions. The intrinsic mechanisms of rhythm regulation from every cell to a whole organism is embedded into the genetic clockwork. The mammalian clock genes are reviewed with their interrelation. The per gene promoter is stimulated by cloc...

24 Hours in the Blogosphere

The majority of weblog posting events are recorded and distributed by ping services. Weblogging is an international phenomenon, a fact reflected in the geographic information presented in many online profiles. By examining 24 hours of ping data from Weblogs.com, a popular ping server, and combining temporal analysis with URL decomposition and the profile information associated with webloggers, ...

Safe orthotopic transplantation of hearts harvested 24 hours after brain death and preserved for 24 hours

OBJECTIVES The aim of this study was to demonstrate safe orthotopic transplantation of porcine donor hearts harvested 24 hours after brain death and preserved for 24 hours before transplantation. DESIGN Circulatory normalization of brain dead (decapitated) pigs was obtained using a new pharmacological regimen (n = 10). The donor hearts were perfused at 8 °C in cycles of 15 min perfusion follo...

[Sleep and biological rhythms].