Word: ago
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Dates: during 1990-1999
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...target is a rogue protein known as beta amyloid, which forms the plaques that fill the brain's memory centers; just two weeks ago scientists identified one of the enzymes that are key to its formation. Another is an abnormal variant of the tau protein, which is thought to clutter the interiors of nerve cells with threadlike tangles. Over the coming years, as a new generation of Alzheimer's drugs enters the clinical pipeline, the arguments that rage today over which is more important, beta amyloid or tau, may be resolved. Kosik suspects that both may be critical...
...that is gradually depriving more than 1 million Americans of their ability to move and speak. The disease is caused by the slow deterioration of brain cells that produce dopamine, a chemical essential for the transmission of messages from the brain to the rest of the body. A decade ago, Swedish researchers started implanting dopamine-producing cells from human fetuses into the brains of Parkinson's patients. The treatment improved the mobility of many of the patients but usually only partly and in some cases not at all. Even if the treatment becomes more successful (and the ethically charged issue...
...Bush draws to a close, neuroscientists are increasingly sanguine that in George Jr.'s lifetime, brain-cell transplants may reverse, if not cure, a host of neurological diseases such as Parkinson's and Alzheimer's, as well as brain damage caused by strokes and head injuries. Even a year ago, such a sweeping claim might have been dismissed as nonsense. But that was before last fall's discovery that the fetal human brain contains master cells (called neural stem cells) that can grow into any kind of brain cell. Snyder extracted these cells and "mass-produced" them...
...down the cells of surrounding tissue and invade it. Vaccines cobbled together from whole cancer cells or bits and pieces of those cells have been shown to boost the body's immune system, helping it recognize and kill tumors on its own. "This was all a dream five years ago," marvels John Minna, director of the Hamon Center for Therapeutic Oncology Research at the University of Texas Southwestern Medical Center in Dallas...
...from reproduction. In the 1960s, the contraceptive pill freed women to enjoy sex for its own sake. At the same time, greater tolerance of homosexuality signaled society's acceptance of nonreproductive sex of another sort. These changes are only continuations of a trend that started perhaps a million years ago. As Richard Wrangham, professor of anthropology at Harvard, points out, "Most mammals lose interest in sex outside a restricted mating period. For a female chimpanzee, copulation is confined to the times when she has a pink swelling on her rump. Outside those lusty periods, she would never think of trying...