The never-ceasing pace of scientific accomplishment often surpasses the progress of moral thought, leaving people struggling to

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问题     The never-ceasing pace of scientific accomplishment often surpasses the progress of moral thought, leaving people struggling to make sense, initially at east, of whether heart transplants are ethical or test-tube babies desirable. Over the past three decades scientists have begun to investigate a branch of medicine that offers astonishing promise—the ability to repair the human body and even grow new organs—but which destroys early-stage embryos to do so. In "The Stem Cell Hope" Alice Park, a science writer at Time magazine, chronicles the scientific, political, ethical and personal struggles of those involved in the work.
    Embryonic stem cells are pluripotent(多功能性的): they have the ability to change into any one of the 200-odd types of cell that compose the human body; but they can do so only at a very early stage. Once the bundle has reached more than about 150 cells, they start to specialize. Research into repairing severed spinal cords or growing new hearts has thus needed a supply of stem cells that come from entities that, given a more favorable environment, could instead grow into a baby.
    Immediately after the announcement of the birth of Dolly the sheep—the clone of an adult ewe whose mammary(乳腺的)cells Ian Wilmut had tricked into behaving like a developing embryo-American scientists were hauled before the nation’s politicians who were uneasy at the implication that people might also be cloned. Concern at the speed of scientific progress had previously stalled publicly funded research into controversial topics, for example, into in vitro fertilization. But it did not stop the work from taking place: instead the IVF industry blossomed in the private sector, funded by couples desperate for a baby and investors who had spotted a profitable new market.
    That is also what happened with human stem cells. After a prolonged struggle over whether to ban research outright—which pitted Nancy Reagan, whose husband suffered from Alzheimer’s disease, against a father who asked George Bush’s advisers, "Which one of my children would you kill?"—Mr. Bush blocked the use of government money to fund research on any new human embryonic stem-cell cultures. But research did not halt completely; Geron, a biopharmaceutical(生物制药的)company based in Menlo Park, California, had started "to mop up this orphaned innovation" , as Ms Park puts it, by recruiting researchers whose work brought them into conflict with the funding restrictions.
    Meanwhile, in South Korea a scientist claimed not only to have cloned human embryos but also to have created patient-specific cultures that could, in theory, be used to patch up brain damage or grow a kidney. Alas, he was wrong. But a Japanese scientist did manage to persuade adult skin cells to act like stem cells. If it proves possible to scale up his techniques, that would remove the source of the controversy over stem-cell research.
    Three months after he took office, Barack Obama lifted restrictions on federal funding for research on new stem-cell cultures, saying that he thought sound science and moral values were consistent with one another. But progress has been slow: the first human trials in America, involving two people with spinal-cord injuries who have been injected with stem celis developed by Geron, are only just under way. The sick children who first inspired scientists to conduct research into stem cells in order to develop treatments that might help them are now young adults. As Ms Park notes, the fight over stem-cell research is not over, and those who might benefit from stem-cell medicine remain in need.
Which of the following statements is CORRECT about the stem cell research?

选项 A、Embryonic stem cells are changeable even in the late stage.
B、Growing new hearts in a patient needs stem cells from an adult donator.
C、Research findings by a Japanese scientist might end the controversy.
D、President Obama agrees with George Bush concerning the issue.

答案C

解析 细节题。根据第五段最后两句提到的但一位日本科学家确实成功地使成人的皮肤细胞表现得像干细胞一样。如果可以证明他的技术可被批量生产,那将会切断干细胞研究争议的源头,由此可知,[C]“一个日本科学家的研究发现可能会终止争议”为正确答案。根据第二段第一句提到的胚胎干细胞具有多能性:它们能发育为200多种人体细胞的任意一种,但只能在其初期阶段完成这些变化,由此可知,[A]“胚胎干细胞在晚期阶段也是可变的”陈述错误,故排除;第二段最后一句提到,修复受伤严重的脊髓或培植新心脏的研究需要干细胞的供给,这些干细胞来自在合适条件下能够发育成婴儿的实体,由此可知,[B]“在病人身体里长出新的心脏需要成人捐献者的干细胞”是对此句句意的曲解,故排除;在干细胞研究的问题上,第四段提到布什总统阻断了联邦政府对其的资助,而在第六段则提到奥巴马总统解除了联邦政府资金上对干细胞研究的限制,可知[D]“在这个问题上,奥巴马总统同意乔治·布什的看法”陈述错误,故排除。
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