British cancer researchers have found that childhood leukaemia is caused by an infection and clusters of cases around industrial sites are the result of population mixing that increases exposure. The research published in the British Journal of Cancer backs up a 1988 theory that some as yet unidentified infection caused leukaemia--not the environmental factors widely blamed for the disease.
"Childhood leukaemia appears to be an unusual result of a common infection," said Sir Richard Doll, an internationally-known cancer expert who first linked tobacco with lung cancer in 1950. "A virus is the most likely explanation. You would get an increased risk of it if you suddenly put a lot of people from large towns in a rural area, where you might have people who had not been exposed to the infection. " Doll was commenting on the new findings by researchers at Newcastle University, which focused on a cluster of leukaemia cases around the Sellafield nuclear repr
A. Most people believe childhood leukaemia is due to environmental factors.
B. Population mixing best explains the cause of childhood leukaemia.
C. Radiation has nothing to do with childhood leukaemia.
D. Children born in a large town are at higher risk of leukaemia.
Section Ⅰ Use of English Directions: Read the following text, Choose the best word (s) for each numbered blank and A, B, C or D on ANSWER SHEET 1. Culture shock might be called an occupational disease of people who have been suddenly transplanted abroad. Like most ailments, it has its own (1) and cure. Culture shock is (2) by the anxiety that results from losing all our familiar signs and symbols of social intercourse. Those signs or cues include the thousand and one (3) in which we orient ourselves to the (4) of daily life: when to shake hands and what to say when we meet people, when and how to give tips, how to (5) purchases, when to accept and when to refuse invitations, when to take statement seriously and when not. These cues, (6) may be words, gestures, facial (7) customs, or norms, are (8) by all of us in the course of growing up and are as much a (9) of our culture as the language we spea
A. situation
B. communication
C. state
D. association
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