问题 单项选择题

一成年男性患者,深龋引起急性根尖炎在某院开髓治疗后,仍有剧烈疼痛,而且面部,于始肿胀。查见髓腔开放开穿髓孔大,根管通畅,叩(+++),龈轻红肿,已服消炎药。分析原因最可能是()

A.开髓孔过小

B.根管不通畅

C.有其他感染源

D.抗感染力不强

E.根尖孔不通畅

答案

参考答案:E

解析:

患牙急性根尖炎髓腔已开放,开髓孔大根管通畅提示A、C两答案已无可能;“服消炎药”已明加强了抗感染处理,病例未提示有其他感染源的可能。叩(++ +)和龈轻红肿提示急性根尖炎仍处于急性根尖脓肿阶段,因此根尖孔不通畅使根尖部积聚的脓液得不到引流是最可能的原因。

阅读理解

American society is not nap (午睡)-friendly. In fact, says David Dinges, a sleep specialist at the University of Pennsylvania School of Medicine, “There’s even a prohibition against admitting we need sleep”. Nobody wants to be caught napping or found asleep at work. To quote a proverb: “Some sleep five hours, nature requires seven, laziness nine and wickedness eleven.”

Wrong. The way not to fall asleep at work is to take naps when you need them. “We have to totally change our attitude toward napping,” says Dr. William Dement of Stanford University, the godfather of sleep research.

Last year a national commission led by Dement identified an “American sleep debt” which one member said was as important as the national debt. The commission was concerned about the dangers of sleepiness: people causing industrial accidents or falling asleep while driving. This may be why we have a new sleep policy in the White House. According to recent reports, President Clinton is trying to take a ha1f-hour snooze (瞌睡) every afternoon.

About 60 percent of American adults nap when given the opportunity. We seem to have “a mid afternoon quiet phase,” also called “a secondary sleep gate.” Sleeping 15 minutes to two hours in the early afternoon can reduce stress and make us refreshed. Clearly, we were born to nap.

We Superstars of Snooze don't nap to replace lost shut-eye or to prepare for a night shift.Rather, we “snack” on sleep, whenever, wherever and at whatever time we feel like it. I myself have napped in buses, cars, planes and on boats; on floors and beds; and in libraries, offices and museums.

小题1:It is commonly accepted in American society that too much sleep is        .

A.unreasonable

B.criminal

C.harmful

D.costly小题2:The research done by the Dement Commission shows that Americans ________.

A.don't like to take naps

B.are terribly worried about their national debt

C.sleep less than is good for them

D.have caused many industrial and traffic accidents小题3:The purpose of this article is to        .

A.warn us of the wickedness of napping

B.explain the danger of sleepiness

C.discuss the side effects of napping

D.convince the reader of the necessity of napping小题4:The underlined phrase “American sleep debt” in Para. 3 is the result of        .

A.the traditional misconception the Americans have about sleep

B.the new sleep policy of the Clinton Administration

C.the rapid development of American industry

D.the Americans' worry about the danger of sleepiness小题5:The second sentence of the last paragraph tells us that it is          .

A.preferable to have a sound sleep before a night shift

B.good practice to eat something light before we go to bed

C.essential to make up for cost sleep

D.natural to take a nap whenever we feel the need for it

单项选择题