Word: oxygenates
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Dates: during 1990-1999
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Like 500,000 other Americans each year, Lee was suffering a stroke. Something had cut off the flow of oxygen and nutrient-rich blood to a portion of her brain. Sometimes the culprit is a leaky artery. But in Phillips' case, as in 80% of strokes, the problem, revealed by a CAT scan, was a clot that was plugging up one of the blood vessels in her head. Unless the clot was dislodged, part of her brain would die, leaving her at least partly paralyzed...
...have at their disposal is a way of preventing the brain from hitting the panic button in the first place. Researchers are studying several compounds, including calcium-channel blockers, that can slow down the metabolism of nerve tissue. The lower rate could help the brain get by on less oxygen and fewer nutrients, thereby lengthening to as much as 12 hours the amount of time doctors have to re-establish normal blood flow...
Although gerontologists acknowledge the interplay of heredity and environment, they tend to fall into camps in explaining how aging works. Wear-and-tear theorists hold that living itself is fundamentally dangerous. The same breath that gives and sustains human life produces oxygen radicals, unstable compounds that when combined with just about anything, have toxic effects on cells. Add to that the weakening over time of the immune system, which leads the body's fight against disease, and decline is inevitable. Biologists are now experimenting on rats and rhesus monkeys to see if restricting the intake of calories (while maintaining healthy...
Toward that end, research is also under way to see if low doses of hormones or high doses of vitamins can reduce the effects of oxygen radicals. The nia is supporting limited research into the risks and benefits of boosting the levels of three hormones that decrease as people age: melatonin, which affects sleep cycles; dehydroepiandrosterone, a product of the adrenal glands that converts to estrogen and testosterone; and human-growth hormone, which affects bone and organ development, as well as metabolic rate. Limited lab tests on animals suggest to some investigators that melatonin may serve as an antioxidant, wiping...
Half a million Americans suffer strokes each year. Four times out of five, the cause is a wayward clot that blocks an artery and robs the brain of oxygen-rich blood. Nerve cells start to die, depriving key parts of the body of the cerebral instructions they need to function. TPA can change all that by dissolving the clot and restoring blood flow before any damage is done to the brain. "It's the first bright sign that we've had that something we're doing actually works," says Dr. Cathy Helgason, a professor of neurology at the University...