Section A Translate the underlined sentences of
the following passage into Chinese. Remember to write the answers on the answer
sheet.
While military scientists test lasers against satellites,
surgeons use them as miraculously accurate scalpels(外科用小刀). They can even be
used to detonate hydrogen bombs. (81) The beam can be focused to spot one
fiftieth the size of a human hair, yet its intensity is enough to kill cancer
cells or drill through the most delicate bones. More than a
decade ago, eye surgeons realized that they could use laser’s beam to seal
individually, the microscopic blood vessels in the retina (视网膜). The beam is so
fine that only the target is heated. Now its pinpoint blasting power has been
turned to destroying cancer cells and reducing birthmarks. For cancer
treatment, the diseased cells must be killed while their healthy neighbors are
left unharmed. (82) Where the cancer can be directly and accurately attacked,
laser treatment does well: early cancer of the cervix (颈) and skin cancers have
been widely and successfully treated. This type of cancer is not very easy
to reach. (83) For cancers that are less accessible there is a new and
potentially valuable technique in which the patient is injected with a chemical
that then attaches itself preferentially to cancer cells. When the laser strikes
the chemical, it releases a form of oxygen that kills these cells. Birthmarks, once almost untreatable, are a mass of blood
vessels and, being red, they absorb the laser beam strongly. It seals them so
that the mark becomes less conspicuous. (84) The normal cells of the skin’s
surface, which don’t absorb much of the laser beam, act in the healing and help
to conceal the mark. The beam can cut with a precision that no scalpel could
achieve. (85) The operation can transform the lives of people who were
previously doomed to a lifetime of cosmetic concealment.
Though this application is widely used in America, there are in Britain
only two hospitals offering the treatment, and one feels bound to warn patients
that success is not certain. However, some 10 new centers will soon be opened.
Britain, though, is one of the leaders in the laser treatment of bleeding peptic
ulcers (胃溃疡) and this, combined with new medicines can mean ulcer treatment
without conventional surgery. The laser is now being used to treat all kinds of
illnesses in this country.