Stem cells emerge at night

Stem cells undergo circadian cycles in humans, emerging from the bone marrow into the bloodstream at higher concentrations at night than in the day, according to a report in __Cell Stem Cell__ linkurl:this week.;http://www.cellstemcell.com/ The study suggests that a simple change in hospital procedures could significantly increase stem cell yield for therapy. "We can take advantage of [the findings] if we coordinate our clinical practices" to harvest stem cells for cancer patients late in the