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IN THE NEWS - Stem Cell Research

作者:Mario Ritter 发布日期:8-18-2001

This is Steve Ember with the VOA Special English program IN THE NEWS.

Last week, President Bush approved limited federal government support of research on special human cells. The research involves stem cells taken from fertilized human eggs called embryos. Many groups disagree with the President's decision. Some religious groups believe that all research on stem cells from embryos should be banned. Yet, many scientists and some lawmakers believe no limits should be put on the research. Private laboratories that do not use federal money are not affected by the limits on the stem cell research.

Stem cells have qualities that may make them highly useful in the treatment of many diseases. The stem cells from embryos are the most useful. They are able to develop into all the tissues of the body. Embryonic stem cells are taken from embryos created in laboratories to help women become pregnant. During the first days, the cells in the embryo divide quickly. Each of these cells is able to become any one of more than two-hundred different kinds of cells in the body. After about four days of development, the embryos are destroyed and the stem cells removed. Adult stem cells are taken from human tissue. These cells have not yet developed to become cells of an organ or a kind of tissue. Removing stem cells does not harm an adult. But adult stem cells are difficult to identify. And, scientists do not know if adult stem cells have the ability to become cells of any kind of organ or tissue. Research suggests that stem cells from embryos can help organs rebuild damaged tissue. Currently, adult stem cells, taken from bone tissue, are used to grow several kinds of blood and bone cells. However, researchers believe that embryonic stem cells could treat diseases of the brain, liver, kidneys and heart. Some experts say new tissue could be grown to replace damaged nerve, muscle and even brain cells. President Bush limited government financial support to sixty existing groups of cells already taken from embryos. These groups of stem cells are now reproducing by themselves in laboratories worldwide. This week, President Bush threatened to veto any bill that offers federal support for research on additional stem cells. Yet, some scientists say that it is impossible to know how many groups of stem cells from embryos will be needed to make discoveries that can save lives. A number of congressmen want expanded research to have full federal support. The religious groups that oppose stem cell research consider it the same as taking human life. Other religious groups accept the research because it could lead to cures for diseases such as Parkinson's and diabetes. A national debate continues over the scientific and moral issues involved in research on embryonic stem cells.

This VOA Special English program, IN THE NEWS, was written by Mario Ritter. This is Steve Ember.

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