全新版大学进阶英语视听说教程第3册 Unit 7 Now Hear This

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A team at Massachusetts General Hospital

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is working on growing an ear in a lab

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to help patients needing transplants.

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What we're looking at is our mouse

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with a half-sized human ear on its back.

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The ear that was grown in the lab is put
onto the back of a mouse.

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It does look a little bizarre.

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But, the whole purpose of this is to see

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if it maintains its shape,

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it maintains, um, its structure.

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It's our first step into essentially what we
would be putting into a human.

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These ears are the adult-sized ears,

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and these will be used for the next stage of
experimentation.

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The nice thing about engineering ears first,

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out of any other organ in the body,

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is that they don't require all of the blood vessels

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that the rest of the organs in the human
body require.

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So, therefore the ear is one of the easier
organs to start with.

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But from this man's point of view, ears are
not so simple.

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He is making the metal support structure for a scaffold.

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It is made of special wire.

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Ears have a complicated shape.

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So the first step is to create a shape that
looks real.

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Also, it's important to create the inner part
of the ear correctly

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so that hearing will be possible.

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This is a digital model of an ear.

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It is exactly the size and shape of a human
ear that the doctors need.

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Next, different types of living ear cells

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and food for the cells are added to the scaffold.

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Then the scaffold is put into a machine
called a bioreactor.

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The inside of the bioreactor is similar to the
human body.

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The ear cells will grow and survive here,

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like they were attached to a real human body.

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It takes approximately two weeks to grow a
living ear in the bioreactor.

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The ear grown in the lab is the first step to
human transplantation.

  • 时长:3.1分钟
  • 来源:外教社 2017-08-22