单选题{{U}}Defects{{/U}} in a system of education should be improved gradually.

They' re petitioning for better facilities for the disabled on public transport.

He is but a child.

Lung Cancer The death rate due to cancer of the lungs has increased more than 800 percent in males and has more than doubled in females during the last 25 years. It is considerably higher in urban and industrial areas than in rural districts. 【B1】______Those factors which have been mentioned most frequently are the presence of foreign particles and other irritants in the air(smoke particles, smog,exhaust fumes),and the smoking of cigarettes and cigars. 【B2】______Among heavy smokers—21 to 30 cigarettes per day—the mortality rate from lung cancer is nearly 17 times the rate from nonsmokers. It is expected the death rate among women will increase as the present high rate of smoking among women has its effect. Sometimes cases of lung cancer are discovered at the time an X-ray is taken for the purpose of detecting tuberculosis. 【B3】______Early detection is absolutely essential if any possibility of cure is to be maintained. Modern X-ray machines in competent hands pose such slight danger, at least to those over 40 years of age, that this would be much more than offset by the advantages of discovering a tumor while it is small enough to be completely removed. 【B4】______The tumor may grow until the bronchus is blocked, cutting off the supply of air to that lung. The lung then collapses, and the secretions trapped in the lung spaces become infected, with a resulting pneumonia or the formation of a lung abscess. 【B5】______The only treatment that offers a possibility of cure, before secondaiy growths have had time to form, is to remove the lung completely. This operation is called pneumonectomy. Malignant tumors of the stomach, the breast, the prostate gland and other organs may spread to the lungs,causing secondary growths.A A common form of lung cancer is bronchogenic carcinoma, so-called because the malignancy originates in a bronchus.B Lung cancer,also known as carcinoma of the lung or pulmonary carcinoma,is a malignant lung tumor characterized by uncontrolled cell growth in tissues of the lung.C Too often, however, a current emphasis upon the danger of exposure to radiation from X-ray machines can frighten people away from routine chest X-rays and thus prevent an early diagnosis of lung cancer.D Numerous studies have demonstrated a striking correlation between the death rate from lung cancer and smoking habits.E Such a lung cancer can also spread to cause secondary growths in the lymph nodes of the chest and neck as well as in the brain and other parts of the body.F There are many possible causes, but it is still controversial which are most blameworthy.

Stage Fright Fall down as you come onstage. That's an odd trick. Not recommended. But it saved the pianist Vladimir Felts man when he was a teenager back in Moscow. The veteran cellist Mstislav Rostropovich tripped him purposely to cure him of pre-performance panic, Mr. Felts man said, All my fright was【C1】______. I already fell. What else could happen?" Today, music schools are addressing the problem of anxiety in classes that 【C2】______ with performance techniques and career preparation. There are a variety of strategies that musicians can learn to【C3】______stage fright and its symptoms; icy fingers, shaky limbs, racing heart, blank mind. Teachers and psychologists offer wide-ranging advice, from basics like learning pieces inside out, 【C4】______mental discipline, such as visualizing a performance and taking steps to relax. Don't【C5】______that you're jittery,they urge; some excitement is natural, even necessary for dynamic playing. And play in public often, simply for the experience. Psychotherapist Diane Nichols suggests some【C6】______for the moments before performance, "Take two deep abdominal breaths, open up your shoulders, then smile," she says. "And not one of these ' please don't kill me' smiles. Then【C7】______three friendly faces in the audience, people you would communicate with and make music to, and make eye contact with them. " She doesn't want performers to think of the audience【C8】______a judge. Extreme demands by mentors or parents are often at the【C9】______of stage fright,says Dorothy Delay, a well-known violin teacher. She tells other teachers to demand only what their students are able to achieve. When Lynn Harrell was 20, he became the principal cellist of the Cleveland Orchestra, and he suffered extreme stage fright. "There were times when I got so【C10】______I was sure the audience could see my chest responding to the throbbing. It was just total panic. I came to a 【C11】______where I thought,If I have to go through this to play music, I think I'm going to look for another job." Recovery, he said, involved developing humility—recognizing that 【C12】______his talent, he was fallible,and that an imperfect concert was not a disaster. It is not only young artists who suffer, of course. The legendary pianist Vladimir Horowitz's nerves were famous. The great tenor Franco Corelli is another example. "They had to push him on stage,'' Soprano Renata Scotto recalled. 【C13】______, success can make things worse. "In the beginning of your career, when you're scared to death, nobody knows who you are, and they don't have any【C14】______, "Soprano June Anderson said. "There's【C15】______to lose. Later on, when you're known, people are coming to see you, and they have certain expectations. You have a lot to lose. Anderson added, "I never stop being nervous until I've sung my last note. "

Mary has made up her mind not to go to the meeting.

Baseline Exam Is Key to Eye Health Even people with no signs or risk factors for eye disease can suffer vision loss and need to get baseline(基线)eye exams at age 40, says the American Academy of Ophthalmology(AAO)(美国眼科学会) The reminder(提示)is part of the AAO's EyeSmart campaign to mark Save Your Vision Month in February. " Many eye diseases progress without any warning signs, " Dr. Stephanie Marioneaux, a clinical correspondent for the AAO, said in a prepared statement. "Gradual changes in vision can affect your ability to function independently and have confidence in your abilities. Based on the findings from the initial screening, an eye doctor will create a schedule for follow-up eye exams. People of any age who have symptoms of eye disease or are at high risk due to family history, diabetes(糖尿病)or high blood pressure should consult with their eye doctor to determine how often they should have their eyes checked, the AAO recommends. By 2020, 43 million Americans will be at significant risk for vision loss or blindness due to age-related eve diseases such as cata-racts(白内障)and glaucoma(青光眼). That's a more than 50 percent increase over the current number of Americans with such vision-threatening diseases. But many Americans are unconcerned about the risk of vision loss. Only 23 percent of Americans are very concerned about losing their vision, while most feel weight gain or joint or back pain are greater worries than vision loss, according to an AAO survey conducted for its EyeSmart campaign.

Eating Potatoes Gives Your Immune System a Boost Eating potatoes is not only good for bowel health, but also for the whole immune system, especially when they come in the form of a potato salad or eaten cold. In a study on an animal model, researchers in Spain found that pigs fed large【C1】______of raw potato starch(RPS)not only had a healthier bowel, but also decreased levels of white blood cells,【C2】______as leucocytes and lymphocytes in their blood. White blood cells are produced as a【C3】______of inflammation or disease, generally when the body is challenged. The general down-regulation of leucocytes observed by the Spanish researchers suggests an overall beneficial effect, a generally more【C4】______body. The reduction in leucocyte levels was about 15 percent. Lower lymphocyte levels are also indicative of【C5】______levels of inflammation , but the observed reduction in both lymphocyte density【C6】______lymphocyte apoptosis is surprising. In 【C7】______was the longest study of its kind, pigs were fed RPS over 14 weeks to 【C8】______the effect of starch on bowel health. "The use of raw potato starch in this experiment is【C9】______to simulate the effects of a diet high in resistant starch," said study leader Jose Francisco Perez at the Universitat Autonoma de Barcelona, Spain. Humans do not eat【C10】______potatoes, but they do eat a lot of foods that contain resistant starch, such as cold boiled potatoes,legumes,grains,green bananas,pasta and cereals. About 10 percent of the starch eaten by human is resistant starch—starch that is not【C11】______in the small intestine and so is shunted into the large intestine where it ferments. Starch consumption is thought to reduce the【C12】______of large bowel cancer and may also have an effect on irritable bowel syndrome(IBS). Immunology expert Lena Ohman' s team【C13】______found that the overall lymphocyte levels do not vary for IBS patients,but that lymphocytes are transferred from the peripheral blood to the gut,which support the hypothesis of IBS being【C14】______least partially an inflammatory disorder. She says the decrease in lymphocytes observed by the Spanish is therefore interesting, and a diet of resistant starch may be worth【C15】______in IBS patients. Ohman is currently at the Department of Internal Medicine, Goteborg University, Sweden. The study is published in the Journal Chemistry and Industry, the magazine of the SCI.

The most crucial problem any economic system faces is how to use its scarce resources.

A infected body fluidsB against the outbreak severityC the mode of transmissionD the initial days of being infectedE three countries in West AfricaF within a wide range of days

The law carries a penalty of up to three years in prison.

The political situation in the region has deteriorated rapidly.

She's extremely competent and industrious .

He said some harsh words about his brother.

We were attracted by the lure of quick money.

The organization was bold enough to face the press.

A in your bodyB without waterC before longD for a changeE on a busy dayF to your weight

Ebola Outbreak1 You are likely aware that several countries in West Africa are battling an Ebola outbreak. Ebola is a dangerous and often lethal viral infection. Scientists believe that humans contracted the virus by eating the meat of rare animals. It is now believed that bats are the primary carriers of the virus.2 To date, there are only three major countries in West Africa experiencing a major outbreak: Sierra Leone, Liberia and Guinea. However, other countries such as Nigeria have reported confirmed cases of Ebola with their border.3 Unless you recently visited one of the three affected West countries, your risk of contracting the virus is virtually zero. Unlike other recent airborne virus outbreaks like SARS, the Ebola virus can only be spread through direct contact with an infected person. Specifically, Ebola is spread through contact with body fluids. Though the vims is transmittable, only an infected person exhibiting symptoms is communicable.4 The signs and symptoms of Ebola are non-specific and patients typically exhibit them after a week of contracting the virus. Symptoms may appear as early as two days or as late as three weeks after initial infection. Symptoms include disgust, weakness and stomach pain. More uncommon symptoms include chest pain, bleeding and sore throat.5 Ebola is devastating because of its ability to attack and replicate in every organ of the body. This causes an overstimulation of the body's inflammatory response, causing the flu-like symptoms. The virus also causes bleeding and impairs the body's normal clotting mechanism(凝血机制), making bleeding even more severe. Loss of blood volume and decreased organ perfusion(器官灌注)ultimately lead to organ failure and death.6 The current outbreak is the deadliest viral outbreak in over 35 years. While diseases such as the malaria(疟疾)are far more communicable, Ebola is one of the world's most fatal viral infections. Ebola's fatality rate exceeds that of SARS.A Am I at risk of contracting the virus?B Is the current outbreak the deadliest?C How do I know if I have contracted the virus?D What areas are currently affected?E What exactly does Ebola do to the body?F What caused the Ebola outbreak?

It is prudent to start any exercise program gradually at first.

He achieved success through hard work.