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Gene therapy and gene-based drugs are two ways we could benefit from our growing mastery of genetic science. But there will be others as well. Here is one of tile remarkable therapies on the cutting edge of genetic research that could make their way into mainstream medicine in the coming years.While it’s true that just about every cell in the body has the instructions to make a complete human, most of those instructions are inactivated, and with good reason: the last thing you want for your brain cells is to start churning out stomach acid or your nose to turn into a kidney. The only time cells truly have the potential to turn into any and all body parts is very early in a pregnancy, when so called stem cells haven’t begun to specialize.Yet this untapped potential could be a terrific boon to medicine. Most diseases involve the death of healthy cells -- brain cells in Alzheimer’s, cardiac cells in heart disease, pancreatic cells in diabetes, to name a few; if doctors could isolate stem cells, then direct their growth, they might be able to furnish patients with healthy replacement tissues.It was incredibly difficult, but last fall scientists at the University of Wisconsin managed to isolate stem cells and get them to grow into neural, gut, muscle and bone cells. The process still can’t be controlled, and may have unforeseen limitations; but if efforts to understand and master stem-cell development prove successful, doctors will have a therapeutic tool of incredible power.The same applies to cloning, which is really just the other side of the coin; true cloning, as first shown with the sheep Dolly several years ago, involves taking a developed cell and reactivating the genome within, resetting its developmental instructions to a pristine state. Once that happens, the rejuvenated cell can develop into a full fledged animal, genetically identical to its parent.For agriculture, in which purely physical characteristics like milk production in a cow or low fat in a hog have real market value, biological carbon copies could become routine within a few years. This past year scientists have done for mice and cows what Ian Wilmut did for Dolly, and other creatures are bound to join the cloned menagerie in the coming year.Human cloning, on the other hand, may be technically feasible but legally and emotionally more difficult. Still, one day it will happen. The ability to reset body cells to a pristine, undeveloped state could give doctors exactly the same advantages they would get from stem cells: the potential to make healthy body tissues of all sorts, and thus to Cure diseases. That could prove to be a true "miracle cure". Towards the genetic research, the author’s attitude can best be said to be that of ().
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"She was America’s princess as much as she was Britain’s princess, "wrote the foreign editor of the normally sharp Chicago Tribune a week after the death in Paris of Diana, Princess of Wales. He was not far off the mark. For Americans have indeed taken posthumous possession of Britain’s "People’s Princess".What was happening How was it that a nation whose school children are taught in history class to look down on the "tyranny" of the English monarchy, suddenly appeared so supportive of a member of the British royal family Why was it that numerous American commentators sought to expand into touch the rumour that Diana had planned to move to the United States to livePart of the answer lies in America’s status as the celebrity culture par excellence. It is from their celebrities that many Americans derive their sense of nationhood. Their presidents must be celebrities in order to be elected. Writer and commentator Norman Mailer made the point after the last presidential election that Bill Clinton won because he projected the image of a Hollywood star, while Bob Dole lost because he came across as a supporting actor.What seems to have happened is that the inhabitants of the nation that produced Marilyn Monroe and Elvis Presley have found it almost impossible to accept that Princess Diana, the world’s biggest, classiest contemporary celebrity by far, should have come from another country. Even that, many seemed to say to themselves, was merely an accident of birth; because in many ways she was so American. Her New Age preferences--the astrologers, the psychics, the aromatherapy--were closer to the style of former US First Lady Nancy Reagan than the House of Windsor. Her dieting and her visits to the gym were lifestyle options that were typically American. Her famous TV confession of adultery and her (purportedly unauthorized) tell-all biography were also hallmarks of the American celebrity approach. Like another former First Lady, Jackie Kennedy, she auctioned her dress-not in London or Pads, but New York. She visited America frequently and felt right at home there, reveling in the generous attentions of the rich and famous and delighting in the unreserved responsiveness of the public to her charms. For she seemed to have adapted brilliantly to another American invention: image manipulation, which all aspirants to political office in the US struggle to learn but which she appeared to have absorbed and refined naturally. She was, in short, a thoroughly modern woman and, like it or not, most of what is modern originates in the united States.But many Americans felt she also had more enduring qualities. Many viewed her as the incarnation of their country’s dominant myth. As an editorial in the Miami Herald put it.. "She was an American dream, a superstar Cinderella with the polish of a natural-born socialite .... In a way she fulfilled the American dream~ to emerge from insignificance and overcome hardship and make something of herself. "Elaine Showalter, a student of American popular culture who teaches English at Princeton University, noted the difference between the dullness of Prince Charles and Diana’s "very American sensibility". "We have a sense here in America that anything is possible, that you are not a predetermined person; that if you are a woman from whom nothing is expected but you want to make your life count, you can do it. She shared that spirit and that’s why she appealed so much to Americans.\ Which of the following statements is TRUE according to the passage().
信念有科学和非科学之分。下列属于科学信念的是
拜金主义人生观、享乐主义人生观、个人主义人生观这三种错误的人生观的共同特征是
When did the Women’s Movement begin in the U. S. A.
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