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  3. 野生大熊猫的数目已不足1000只，大熊猫临绝迹。拯救国宝大熊猫已成为中国人民的共同心愿 自20世纪90年代初以来，我们用人工授精(artific

野生大熊猫的数目已不足1000只，大熊猫临绝迹。拯救国宝大熊猫已成为中国人民的共同心愿 自20世纪90年代初以来，我们用人工授精(artific

游客2025-05-09  33
问题     野生大熊猫的数目已不足1000只，大熊猫临绝迹。拯救国宝大熊猫已成为中国人民的共同心愿
    自20世纪90年代初以来，我们用人工授精(artificial insemination)的方法增加大熊猫数量。但是就整个大熊猫家族的命运来说，人工授精的方法远未令人满意。此外，通常大熊猫产生的卵子和精子数量很少，所以当雌性大熊猫无法交配时，这种方法也就起不了作用。1997年，开始实施一个更为雄心勃勃的计划——克隆大熊猫。1998年中国科学院在这个项目上投入了专款，并在1999年得到了科学技术部的资助。这项实验旨在将大熊猫体细胞的细胞核植入去核卵子以造就一个全新的生命。
    我们注意到，真正的问题是克隆大熊猫的第二步，即在另一种动物的子宫里(denucleated ovum)培育新的大熊猫。目前我们还无法肯定哪一种动物是理想的“代母体(surrogate mother)”。另一个问题是，即使大熊猫克隆出来，它只有亲本的DNA。因此，在某种程度上，克隆方法是无法保护大熊猫的。
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答案     There are only less than 1,000 pandas still alive in the wild; pandas are on the verge of extinction. Saving pandas, Chinas national treasure, from extinction has become a common aspiration of the Chinese people.
    Since early 1990s, we have used artificial insemination to increase the number of pandas. But the method of artificial insemination is still far from satisfactory with regard to the fate of the whole family.  Moreover, because pandas usually produce only a small number of eggs and sperms, and when the female panda cant take part in the mating, the method wont work.
    In 1997, the more ambitious planto clone the panda started. The project was injected with special funds by the Chinese Academy of Sciences in 1998, and backed by investment from the Ministry of Science and Technology in 1999. The experiment aims to implant a nucleolus of a pandas body cell into a denucleated ovum, thus producing a completely new being.
    We are aware that the true challenge is the second step of cloning a panda producing a new panda baby in the matrix of another kind of animals. At present, we re not sure which animal will be the ideal surrogate mother. Even if a panda is cloned, it only has the DNA of the panda that provided the body cell. Therefore, to a certain degree, cloning does nothing to protect the animals.
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