Phys Ed: Phys Ed: Are Marathons Bad for the Heart?
The death from heart attack of the ultramarathoner Micah True has raised awareness about the safety of marathon racing and training. But the science suggests that distance running and racing are extremely unlikely to kill you -- except when, in rare instances, they do. (Source: NYT Health)

Arsenic trioxide/tretinoin: Neutropenia, QTc prolongation and electrolyte abnormalities: 3 case reports
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