题目内容
Natural MedicinesSince earliest days, humans have used some kinds of medicines. We know this because humans have survived. Ancient treatments for injury and disease were successful enough to keep humans from dying out completely.They were successful long before the time of modern medicine. Before the time of doctors with white coats and shiny (发亮的) instruments. Before the time of big hospitals with strange and wonderful equipment.Many parts of the world still do not have university-educated doctors. Nor do they have expensive hospitals. Yet injuries are treated. And diseases are often cured. How By ancient methods. By medicines that might seem mysterious, even magical (有魔力的). Traditional medicines are neither mysterious nor magical, however.Through the centuries, tribal (部族的) medicine men experimented with plants. They found many useful chemicals in the plants. And scientists believe many of these traditional medicines may provide the cure for some of today’s most serious diseases.Experts say almost 80% of the people in the world use plants for health care. These natural medicines are used not just because people have no other form of treatment. They are used because people trust them. In developed areas, few people think about the source of the medicines they buy in a store. Yet many widely-used medicines are from ancient sources, especially plants. Some experts say more than 25% of modern medicines come, in one way or another, from nature.Scientists have long known that nature is really a chemical factory. All living things contain chemicals that help them survive. So scientists’ interest in traditional medicine is not new. But it has become an urgent concern. This is because the earth’s supply of natural medicines may be dropping rapidly. It can be seen from the passage that the earth’s supply of natural medicines()
查看答案
搜索结果不匹配？点我反馈
更多问题
通过有人看守的铁路道口时，服从道口管理人员指挥，不要与火车抢道。
Concern with money, and then more money, in order to buy the conveniences and luxuries of modern life, has brought great changes to the lives of most Frenchmen. More people are working than ever before in France. In the cities the traditional leisurely midday meal is disappearing. Offices, shops, and factories are discovering me great efficiency of a short lunch hour in company lunchrooms. In almost all lines of work emphasis now falls on ever-increasing output. Thus the "typical" Frenchman produces more, earns more, and buys more goods than his counterpart of the last generation. He gains in creating comforts and ease of life. What he loses to some extent is his sense of persona, uniqueness, or individuality. Some say that France has been Americanized. This is because the U.S. is a world symbol of the technological society and its consumer products. The so-called Americanization of France has its critics. They fear that "assembly-line life" will lead to the disappearance of the pleasures of the more graceful and leisurely (but less productive) old French style. What will happen, they ask, to taste, elegance, and the cultivation of the good things in life—joy in the smell of a freshly picked apple, a stroll by the river, or just happy hours of conversation in a local caf6 Since the late 1950s life in France has indeed taken on qualities of rush, tension, and the pursuit of material gain. Some of the strongest critics of the new way of life are the young, especially university students. They are concerned with the future, and they fear that France is threatened by the triumph of this competitive, goods-oriented culture. Occasionally, they have reacted against the trend with considerable violence. In spite of critics, however, countless Frenchmen are committed to keeping France in the forefront of the modern economic world. They find that the present life brings more rewards, conveniences, and pleasures than that of the past. They believe that a modern, industrial France is preferable to the old. According to the passage, all the following are the description of today’’s Frenchmen EXCEPT that
行车中发动机突然熄火后不能起动时，及时靠边停车检查熄火原因。
What is a Species A species of plants or animals, as the term has been generally used by naturalists, comprises all such individuals as are so similar to each other that we may suppose them all to have proceeded from one common parentage, and so dissimilar from all others that they could not have been reproduced from the others, nor the others produced from them. All we know is, that the plants and animals throughout the world exist in species, each one of which stands at present distinct and isolated wholly apart from all the rest, and one cannot be transformed into another by ordinary generation, through changes of soil and climate, or any other causes whatever known to man, within so short a period as six thousand years. The apple, for instance, is one species, and the pear is another. In many respects they are similar to each other, and each may be changed by cultivation and by the operation of other causes a great deal, but by no possibility can one be derived from the other. By different modes of cultivation, by different selections of seeds, by changes in soil, and by other such means, a horticulturist (园艺家) may vary the character of his apples very much. He may produce large apples and small apples, sweet apples and sour apples, apples with a skin red, green, yellow, or brown, but he can never produce a pear. The apple, under all its modifications, will remain an apple still. It is the same with animals. Each one is subject to a great many modifications in respect to its form, its size, its color, and even it faculties, but through all these changes each one remains entirely within its own bounds, as it were. The distinguishing characteristics of the species remain unchanged. Take for instance, any species of the dog. We may, perhaps, by means of differences of treatment, of food, of climate, or of immediate parentage, buy big dogs and little dogs, weak dogs and strong dogs, gentle dogs and fierce dogs, all proceeding from the same original stock.The Distinction of Species Is Very Permanent Although in the comparatively short periods of time, by the experiments and observations which have been made, man can not transform one species into another. Such changes may have been effected in longer periods. Now evidence has shown that the various forms of animal and vegetable life which now exist upon the earth may have proceeded from some common origins, or at least from some moderate number of original types existing in former ages. And, indeed, this may possibly be so. But there seems to be quite satisfactory evidence to prove that the distinction of species is as permanent in respect to the past and the future, at least for very long periods, as it is decisive at the present time.Evidence of Ancient Records In the first place, we have in Egyptian and Assyrian monuments, many drawings and other representations of plants and animals as they existed then, and even seeds, in some cases, found in the wrappings of Egyptian mummies (木乃伊’’), all of which show that these plants and animals, and even the races of men, were specifically the same then as now. There have been no changes whatever that blur (模糊，混淆) the limits and bounds by which the different species are separated from each other at the present day, or confuse the lines of demarcation (界线) in any degree. There is no approach of one type toward another, nor any tendency to such an approach. Between the bird carved upon an Egyptian or Assyrian slab (平板), and its representative at the present day, probably three thousand generations may have intervened, and yet the present living specimen is specifically identical with the delineation of its ancestor. The great comparative anatomist Cuvier examined the mummy of an ibis (朱鹭), from three to four thousand years old, comparing it minutely (细微地) with a living bird of the present day, and found the two specimens in all respects identically the same. There is also a bass-relief from the ruins of Babylon, with a dog represented upon it, which is found by naturalists to be identical with a species of the dog existing in Asia at the present day.Evidence of Fossil Remains But we have still more conclusive evidence than this. It is found in the. fossil remains which exist in the strata of the earth. It also indicates the very great permanence of the characteristics by which different species of plants and animals are distinguished from each other. By means of these, our observations upon the forms of vegetable and animal life which have existed upon our globe may be carried back to an immense antiquity (古老) and extended over so vast a number and variety of species. So, as it has always been supposed, we can get all the means of information on this subject that can be desired. It has been thought to be fully proved by these observations that every species which exists upon the earth remains unchanged so long as it exists. When at length its period has expired, it disappears from the field, while new ones are continually arising to take the place of those that are gone. But no one passes, by gradations, into any other; and the lines of distinction by which each is separated from all the rest remain sharp and well-defined from the beginning to the end. The__________ Cuvier examined the mummy of an ibis, comparing it in detail with a living bird of the present day, and found the two specimens in all respects__________.
微信支付 
支付宝支付