Lack of Sleep Increases the Risk of Catching a Cold

As cold season approaches, many Americans stock up on their vitamin C and Echinacea (紫锥花精油). But fallowing the age -old advice about catching up on sleep might be more important.
Studies have demonstrated that poor sleep and susceptibility (易受影响) to colds go hand in hand, and scientists think it could be a reflection of the role sleep plays in maintaining the body’s defenses.
In a recent study for the Archives of Internal Medicine, scientists followed 153 men and women for two weeks, keeping mack of their quality and duration of sleep. Then, during a five - day period, they quarantined (进行检疫隔离) the subjects and exposed them to cold viruses. Those who slept an average of fewer than seven hours a night, it turned out, were three times as likely to get sick as those who averaged at least eight hours.
Sleep and immunity, it seems, are tightly linked. Studies have found that mammals that require the most sleep also produce greater levels of disease - fighting white blood cells--but not red blood cells, even though both are produced in bone marrow (骨髓) and stem from the same precursor (前体物). And researchers at the Max Planck Institute for Evolutionary Anthropology have shown that species that sleep more have greater resistance against pathogens (病原体).
"Species that have evolved longer sleep durations," the Planck scientists wrote, "appear to be able to increase investment in their immune systems and be better protected. \
What can we learn from the passage

A. The physician has been able to make wonders alone in the world of medicine.
B. The cooperation between research workers in medicine and in the related sciences will bring about a "golden age of healing".
C. The X-ray and the microscope have been of little help in uncovering truth.
D. Medical workers fully understand electrical body measurements.

All subjects were free of cancer at enrollment between 1992 and 1998, but (53) an average follow-up of almost 5 years 1,329 bowel cancers had been reported.
The subsequent analysis, published in the Journal of the National Cancer Institute, confirms the long-held suspicion (54) high intakes (纳入量) of red meat are associated with increased bowel (55) risk.After taking into consideration factors like age, sex, height, weight, energy intake, physical activity, smoking, and alcohol consumption, the investigators found that bowel cancer was (56) with intake of red and processed meat but not chicken.
Risk of bowel cancer dropped with increasing intake of fish. Eating more than 80 grams a day of fish was associated (57) a 31 percent reduction in risk compared with eating less than 10 grams a (58) .
Subjects with high red meat and low fish intake were at 63 percent higher risk of bowel cancer compared with subjects with low red meat and high fish (59) . In addition, the risk of developing the disease was increased for (60) people who ate a low fibre diet.
Sheila Bingham, study investigator at the UK’s Medical Research Council nutrition unit, said: "People have suspected for some time that high levels of red and processed meat (61) risk of bowel cancer, but this is one of the largest studies worldwide and the first from Europe of this type to show a (62) relationship."
She added in a statement: "The overall picture is very consistent for red and processed meat and fibre across all the (63) populations studied."
Study coordinator, Elio Riboli, of the World Health Organisation International Agency for Research into Cancer, said: "Other risk factors for (64) cancer include obesity (肥胖) and lack of physical activity. Smoking and excess alcohol may also play a (65) . These factors were all taken into account in the analysis.\