Even though
ulcers appear to run in families, lifestyle plays more of a role than genetic
factors in causing the illness, according to a report in the April 13th Journal
of Internal Medicine. In particular, smoking and stress in men
and the regular use of pain releasing medicines in women were linked with an
increased risk of developing all ulcers. Overall, 61% of ulcer
risk appears to be due to environmental factors, such as smoking, and the
remaining 39% is due to genes according to Dr. Ismo Raiha Of the University of
Turky and colleagues at the University of Helsinki, Finland. Some researchers
had suggested that families may spread Helicobacteria pylori, the bacteria that
can cause ulcers. However, the new study suggests this is unlikely, according to
the report. Raiha and colleagues studied data from more than
13,000 pairs of twins "to examine the roles of genetic and environmental factors
in the origin of peptic ulcer disease", they explain. Both twins were more
likely to develop an ulcer if the pair were genetically the same as compared
with a pair of fraternal twins, suggesting that there must be some genetic
susceptibility to ulcer development. However, the risk was no
greater in twins living together compared with twins living apart, suggesting
that shared exposure to H. pylori (幽门螺旋菌) was not to blame. "Environmental
effects were not due to factors shared by family members, and they were related
to smoking and stress in men and the use of analgesics in women," the authors
wrote. "The minor effects of shared environment to disease liability do not
support the concept that the grouping of risk factors, such as H. pylori
infection, would explain the genetic factor of peptic ulcer disease, "they
concluded.
单选题
According to the passage, which of the following is a very likely cause
of ulcer in men?
A. Smoking and stress.
B. Drinking and smoking.
C. Genes and children.
D. Use of a certain medicine.
【正确答案】
A
【答案解析】[解析] 因第二段中提到“smoking and stress in men...”，其他各项均与文中内容不符。故选A。
单选题
What factors contribute to over half the ulcers?
A. Hereditary factors.
B. Economic factors.
C. Environmental factors.
D. Genetic factors.
【正确答案】
C
【答案解析】[解析] 第三段第一句提到：“Overall, 61% of ulcer risk appears to be due to environmental factors...”，故选C。
单选题
In relation to ulcers, experts study twins in order to examine ______.
A. the roles of genetic factors
B. the roles of environmental factors
C. the roles of both genetic and environmental factors
D. the roles of brotherhood
【正确答案】
C
【答案解析】[解析] 第四段谈到这项研究的目的，即“examine the roles of genetic and environmental factors...”，故选C。
单选题
"Environmental effects" in the fifth paragraph refers to effects
brought about by ______.
A. a clean environment
B. smoking and stress in men and use of pain-killing medicine in women
C. factors shared by family members such as genes and the food they
eat
D. shared exposure to H. pylori infection
【正确答案】
B
【答案解析】[解析] 第五段明确指出“they were related to smoking and stress in men and the use of analgesics in women”，故选B。
单选题
The passage argues that ______.
A. ulcers are related to genes
B. ulcers are chiefly related to lifestyle
C. ulcers appear in men and women
D. ulcers are caused by H. pylori infection
【正确答案】
B
【答案解析】[解析] 从全文看，文章主旨在第一段已提出，即“...lifestyle plays more of a role than genetic factors in causing the illness”，故选B。