Among all the malignancies, lung cancer is the biggest killer; more than 100,000 Americans die of the disease. Giving up smoking is one of obvious ways to reduce the risk, but another answer may lie in the kitchen. According to a new report, even heavy smokers may be protected from developing lung cancer by eating a daily portion of carrots, spinach or any other vegetable or fruit containing a form of vitamin A called carotene. The finding, published in THE LANCET, is part of a long-range investigation of diet and disease. Since 1957, some American researchers have monitored the dietary habits and medical histories of 2,000 middle-aged men employed by the Western Electric Co. in Chicago. Led by Dr. Richard Shekelle of St. Luke’s Medical Center, the researchers recently began to sort out the links between the subjects’ dietary patterns and cancer. Other studies of animals and humans have suggested that vitamin A offer some protection against lung cancer. The correlation seemed logical, explains Shekelle, since vitamin A is essential for the growth of the epithelial tissue that lines the airways of the lungs. Vegetables: But the earlier research did not distinguish between the two different forms of the vitamin. “Preformed“ vitamin A, known as retinols found mainly in liver and dairy products like milk, cheese, butter and eggs. But vitamin A is also made in the body from carotene, which is abundant in a variety of vegetables and fruits, including carrots, spinach, squash, tomatoes, sweet potatoes and apples. In the study, Shekelle and his colleagues found little correlation between the incidence of lung cancer and the consumption of foods containing preformed vitamin A. But when they examined the data on carotene intake, they discovered a significant relationship. Among the 488 men who had the lowest level of carotene consumption, there were 14 cases of lung cancer; in a group of the same size that ate the most carotene, only two cases developed. The apparent protective effect of carotene held up even for long-time smokers—but to a lesser degree. Further studies will be necessary before the link between lung cancer and carotene can be firmly established. In the meantime, researchers warn against taking large numbers of vitamin A pills, because the tablets contain a form of the chemical that can be extremely toxic in high doses. Instead, they advise a well-balanced diet that includes goods rich in carotene. For a smoker, a half-cup of carrots every day might possibly make the difference between life and death.

W: Look outside and see how beautiful the snow is. M: So we did get snow after all. Q: What had the man assumed? The woman doesn’t like cold weather. The snow would get dirty quickly. It wouldn’t snow. All the snow would melt.

If you______a heart-attack or stroke victim who needs your assistance, your first response should be to stay calm and urge bystanders to call for an ambulance. find out go into pass by come across

Despite the limitations of a standard CT, it does a______job of picturing the internal anatomy of the body. supreme superb sufficient superfluous

The city government is getting its residents to properly______their garbage. break up dispose of check out hand out

A substantial hike in the top rate of income tax would not solve this problem but merely aggravate the nation’s already waning support. depreciating warning declining startling

If a mother pushes her small son in a swing, giving only a light force each time he returns, eventually he will be swinging quite high. The child can do this for himself by using his legs to increase the motion, but both the mother’s push and the child’s leg movements must occur at the proper moment, or the extent of the swing will not increase. In physics, increasing the swing is increasing the amplitude; the length of the rope on the swing determines its natural oscillation period. This ability of an object to move periodically or to vibrate when stimulated by a force operating in its natural period is called resonance. Resonance is observed many times without consciously thinking about it; for example, one may find an annoying vibration or shimmy in an automobile, caused by a loose engine mount vibrating with increasing amplitude because of an out-of-round tire. The bulge on the tire slaps the pavement with each revolution; at the natural resonance point of the engine mount, it will begin to vibrate. Such vibrations can result in considerable damage if allowed to persist. Another destructive example of resonance is the shattering of a crystal goblet by the production of a musical tone at the natural resonant point of goblet. The energy of the sound waves causes vibration in the glass; as its amplitude increases, the motion in the glass exceeds the elasticity of the goblet, and it shatters. An instrument called a tachometer makes use of the principle of resonance. It consists of many tiny bars, loosely fastened together and arranged so that each bar can slide independently of the others. Movement of the bars causes changes in a dial. When placed next to a rotating motor or engine, the tachometer picks up slight vibrations which are transferred to the resonant bars. These bars begin to move, and the resulting dial may be read to find the revolutions per minute of the motor very quickly.

Since the first brain scanner was constructed several years ago, computed tomography or computed medical imagery, has become fairly widely used. Its rapid acceptance is due to the fact that it has overcome several of the drawbacks of conventional X-ray technology. To begin with, conventional two-dimensional X-ray pictures cannot show all of the information contained in a three-dimensional object. Things at different depths are super imposed, causing confusion to the viewer. Computed tomography can give three-dimensional information. The computer is able to reconstruct pictures of the body’s interior by measuring the varying intensities of X-ray beams passing through sections of the body from hundreds of different angles. Such pictures are based on series of thin “slices“. In addition, conventional X-ray generally differentiates only between bone and air, as in the chest and lungs. They cannot distinguish soft tissues or variations in tissues. The liver and pancreas are not discernible at all, and certain other organs max only be rendered visible through the use of radio paque dye. Since computed tomography is much more sensitive, the soft tissues of the kidneys or the liver can be seen and clearly differentiated. This technique can also accurately measure different degrees of X-ray absorption, facilitating the study of the nature of tissue. A third problem with conventional X-ray methods is their inability to measure quantitatively the separate densities of the individual substances through which the X-ray has passed. Only the mean absorption of all the tissues is recorded. This is not a problem with computed tomography. It can accurately locate a tumor and subsequently monitor the progress of radiation treatment, so that in addition to its diagnostic capabilities, it can play a significant role in therapy.

When imaginative men turn their eyes towards space and wonder whether life exists in any part of it, they may cheer themselves by remembering that life need not resemble closely the life that exists on Earth. Mars looks like the only planet where life like ours could exist, and even this is doubtful. But there may be other kinds of life based on other kinds of chemistry and they may multiply on Venus or Jupiter. At least we cannot prove at present that they do not. Even more interesting is the possibility that life on their planets may be in a more advanced stage of evolution. Present-day man is in a peculiar and probably temporary stage. His individual units retain a strong sense of personality. They are, in fact, still capable under favorable circumstances of leading individual lives. But man’s societies are already sufficiently developed to have enormously more power and effectiveness than the individuals have. It is not likely that this transitional situation will continue very tong on the evolutionary time scale. Fifty thousand years from now man’s societies may have become so close-knit that the individuals retain no sense of separate personality. Then little distinction will remain between the organic parts of the multiple organism and the inorganic parts(machines)that have been constructed by it. A million years further on man and his machines may have merged as closely as the muscles of the human body and the nerve cells that set them in motion. The explorers of space should be prepared for some such situation. If they arrive on a foreign planet that has reached an advanced stage(and this is by no means impossible), they may find it being inhabited by a single large organism composed of many closely cooperating units. The units may be “secondary“—machines created millions of years ago by a previous form of life and given the will and ability to survive and reproduce. They may be built entirely of metals and other durable materials, if this is the case, they may be much more tolerant of their environment multiplying under conditions that would destroy immediately any organism made of carbon compound and dependent on the familiar carbon cycle. Such creatures might be relics of a past age, many millions of years ago, when their planet was favorable to the origin of life or they might be immigrants from a favored planet.

M: Here I am. I’m lucky I made it to the exam on time. W: I can see you were in a hurry. You are wearing your sweater inside out. Q: What does the woman mean? The man hurried through the exam. The room is too warm for a sweater. The man will be late if he doesn’t hurry. The man put his sweater on the wrong way.

W: I have read your letter here. You seem to have done well at school. Can you tell me something about your school work? M: As you can see, my strongest subjects were art subjects. My best subject was history and my second best was geography. However, my favorite subject was math and the results I got in the math paper were quite reasonable. Q: According to the conversation, what subject is the man not strong in? History. Geography. Mathematics. Art.

Before the 1870’s, trained nurses were virtually unknown in the United States. Hospital nursing was an unskilled occupation, taken up by women of the lower classes, some of whom were from the charity house. The movement for reform originated not with doctors, but among upper-class women, who had taken on the role of guardians of a new hygienic order. Though some doctors approved of the women’s desire to establish a nurses’ training school, which would attract the daughters of the middle class, other medical men were opposed. Plainly threatened by the prospect, they objected that educated nurses would not do as they were told. When resisted, as they were at Bellevue in efforts to install trained nurses on the maternity wards, they went over the heads of the doctors to men of their own class of greater power and authority. Professional nursing, in short, emerged neither from medical discoveries nor from a program of hospital reform initiated by physicians; outsiders saw the need first. Questions 21-25 are based on the passage you have just heard. 21. According to the passage, what could best describe nurses in the United States in the 1850’s? 22. Who is the first advocate of nursing training in the United States? 23. According to the passage, why some doctors objected to the establishment of nursing schools? 24. Which of the following is discussed in the passage? 25. What can be inferred from the passage? Poor, untrained women. Young medical students. Wives of military officers. Middle-class men and women.

You are healthy when you are______your outer and inner environments. in relation to with regard to in contrast with in harmony with

Good health is a spirited______of energy, smooth skin, strong, supple limbs, and a positive joy in life. texture mix burst peak

Work is a______of satisfaction. measure terminal source resource

Today people still don’t make health a(n)______because they have no time. privilege issue principle priority

The recent deterioration in the economy is of great concern to the government. depression deficiency degeneration deformity

He was not conspicuously hairy nor shiny-bald, but his hair was graying and receding tactfully in keeping with his age. prominently warily consciously conventionally

The water company is obliged to maintain a supply of wholesome water. available hydraulic balanced hygienic

Instead of being recycled, garbage is left to accumulate in insanitary heaps which attract flies and spread infectious diseases. innocuous gathering filthy inflammable

Shyness, the most common form of social anxiety, occurs when a person’s apprehensions are so great that they inhibit his making an expected or desired social response. discharge trigger restrain defer

The word “malignancy“(Line 1, Para. 1)most probably refers to______.

Preformed vitamin A is NOT found in______.

Carotene is present in all of the following EXCEPT______.

Among the groups studied, who had the most cases of lung cancer?

What is needed to establish firmly the link between carotene and lung cancer?