At Philadelphia’s Children’s Hospital, Neurosurgeon Eugene Spitz, 37, tried running a tube direct from baby Charles ... need a valve (to prevent back flow by the blood), and so far no ...

Multiple coastal cities in Northeast China's Liaoning Province and North China's Hebei Province suffered from flooding on Monday due to the backflow of seawater from the coast to inland ...

the largest artery is the aorta Contain valves to prevent back flow of blood Walls are made of semi-permeable membrane to allow transport of gases and nutrients into and out of the blood Function ...