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Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 23 to 27.           Coincident with concerns (23) ______ the accelerating loss of species and habitats has been a growing appreciation of the importance of biological diversity, the number of species in a particular ecosystem, to the health of the Earth and human well-being. Much has been written about the diversity of terrestrial organisms, particularly the exceptionally rich life associated tropical rain­forest habitats. Relatively little has been said, (24) _____, about diversity of life in the sea even though coral reef systems are comparable to rain forests in terms of richness of life.           An alien exploring Earth would probably (25) ______ priority to the planet's dominants - most distinctive feature - the ocean. Humans have a bias toward land (26) _____ sometimes gets in the way of truly examining global issues. Seen from far away, it is easy to realize that landmasses occupy only one-third of the Earth's surface. Given that two thirds of the Earth's surface is water and that marine life lives at all levels of the ocean, the total three-dimensional living space of the ocean is perhaps 100 times (27) _____ than that of land and contains more than 90 percent of all life on Earth even though the ocean has fewer distinct species. Question 27

Xem chi tiết 2.1 K lượt xem 5 năm trước

Read the following passage and mark the letter A, B, C, or D to indicate the correct word or phrase that best fits each of the numbered blanks. Oxbridge is a word made from the names Oxford and Cambridge and is used to refer (46)_____ to the universities of Oxford and Cambridge together, especially when they are being distinguished from other universities. Oxford and Cambridge are the oldest universities in Britain. They are generally also thought to be the best universities to get a place at. An Oxbridge degree (47)_____ a good impression on many employers, and graduates of these universities may have an advantage when applying for jobs. The upper class has traditionally sent their children to Oxbridge, and many prime ministers and politicians went there. To many people, Oxford and Cambridge seem very remote places (48)_____ only the very privileged can go. The teaching system is different from that at most other universities. Students have tutorials, called supervisions at Cambridge, (49)_____ which they read their essays to their tutor. Terms are short and intense, and students are expected to prepare for them in the vacations. Final examinations at Oxford are called schools, and at Cambridge the trips. Undergraduates at Oxford and Cambridge study for a BA degree, but after a period of time graduates can (50)_____ their BA to an MA without doing any further study. Điền vào đáp án 45

Xem chi tiết 1.2 K lượt xem 5 năm trước

Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the question. Alaska is disappearing slowly, but surely. It is estimated that since the 19505, as much as fifteen percent of Alaska's land area has disappeared. How can a whole state be disappearing? The problem is that Alaska’s glaciers are melting. The state has more than 100,000 glaciers. These glaciers account for about 75,000 square kilometers, or five percent, of the state’s area. That is an area of land larger than Ireland! According to a recent report by the US Geological Survey, ninety-nine percent of Alaska's glaciers are either retreating or diminishing. This diminishing seems mainly due to the increase in global temperatures. Since the 19605, the average year-round temperature has increased by almost 3°C. Additionally, the average winter temperature has increased by over 6°C. Presently, an estimated 100 cubic kilometers of ice is disappearing from Alaskan glaciers every year. It may be even more in the near future, as some scientists predict that the average world temperature could go up 4 to 7°C by the year 2100. Another problem facing Alaska is its thawing permafrost. Much of the land in Alaska used to be permanently frozen or frozen for most of the year. Now, the thawing permafrost is causing a number of problems for people living in Alaska. Roads and utility poles are collapsing as the ground around and under them warms and soften. Also, the hard permafrost that originally prevented beaches from eroding during violent storms is now melting. People who live along Alaska's coasts are being forced to relocate. For villages on small low islands, one terrible storm could wipe out the entire community. The melting permafrost and increasing temperatures are both affecting the forests of Alaska. As the permafrost under the forests melts, insects that normally do not turn up until the warmer seasons are appearing sooner. The spruce-bark beetle, for example, is increasing in numbers as a result of warmer winter temperatures. It usually takes about two years for these beetles to grow and reproduce in. very cold weather. However, due to the increase in temperatures, spruce-bark beetles are reproducing faster and damaging as many trees in one year as they previously damaged in two. If something cannot be done to change things, Alaska's forests will not survive the turn of the century. Some scientists believe that human activity is linked to a global increase in weather temperature. Whatever the cause of rising temperatures may be, the fact remains that temperatures are warming, affecting Alaska for the worse. Horribly, this could be a preview of what will happen to the rest of the world in the next century. What is predicted in the last paragraph? 

Xem chi tiết 2.5 K lượt xem 5 năm trước

Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the question. Alaska is disappearing slowly, but surely. It is estimated that since the 19505, as much as fifteen percent of Alaska's land area has disappeared. How can a whole state be disappearing? The problem is that Alaska’s glaciers are melting. The state has more than 100,000 glaciers. These glaciers account for about 75,000 square kilometers, or five percent, of the state’s area. That is an area of land larger than Ireland! According to a recent report by the US Geological Survey, ninety-nine percent of Alaska's glaciers are either retreating or diminishing. This diminishing seems mainly due to the increase in global temperatures. Since the 19605, the average year-round temperature has increased by almost 3°C. Additionally, the average winter temperature has increased by over 6°C. Presently, an estimated 100 cubic kilometers of ice is disappearing from Alaskan glaciers every year. It may be even more in the near future, as some scientists predict that the average world temperature could go up 4 to 7°C by the year 2100. Another problem facing Alaska is its thawing permafrost. Much of the land in Alaska used to be permanently frozen or frozen for most of the year. Now, the thawing permafrost is causing a number of problems for people living in Alaska. Roads and utility poles are collapsing as the ground around and under them warms and soften. Also, the hard permafrost that originally prevented beaches from eroding during violent storms is now melting. People who live along Alaska's coasts are being forced to relocate. For villages on small low islands, one terrible storm could wipe out the entire community. The melting permafrost and increasing temperatures are both affecting the forests of Alaska. As the permafrost under the forests melts, insects that normally do not turn up until the warmer seasons are appearing sooner. The spruce-bark beetle, for example, is increasing in numbers as a result of warmer winter temperatures. It usually takes about two years for these beetles to grow and reproduce in. very cold weather. However, due to the increase in temperatures, spruce-bark beetles are reproducing faster and damaging as many trees in one year as they previously damaged in two. If something cannot be done to change things, Alaska's forests will not survive the turn of the century. Some scientists believe that human activity is linked to a global increase in weather temperature. Whatever the cause of rising temperatures may be, the fact remains that temperatures are warming, affecting Alaska for the worse. Horribly, this could be a preview of what will happen to the rest of the world in the next century.  What does the word “they” in paragraph 4 refer to?

Xem chi tiết 2.7 K lượt xem 5 năm trước

Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the question. Alaska is disappearing slowly, but surely. It is estimated that since the 19505, as much as fifteen percent of Alaska's land area has disappeared. How can a whole state be disappearing? The problem is that Alaska’s glaciers are melting. The state has more than 100,000 glaciers. These glaciers account for about 75,000 square kilometers, or five percent, of the state’s area. That is an area of land larger than Ireland! According to a recent report by the US Geological Survey, ninety-nine percent of Alaska's glaciers are either retreating or diminishing. This diminishing seems mainly due to the increase in global temperatures. Since the 19605, the average year-round temperature has increased by almost 3°C. Additionally, the average winter temperature has increased by over 6°C. Presently, an estimated 100 cubic kilometers of ice is disappearing from Alaskan glaciers every year. It may be even more in the near future, as some scientists predict that the average world temperature could go up 4 to 7°C by the year 2100. Another problem facing Alaska is its thawing permafrost. Much of the land in Alaska used to be permanently frozen or frozen for most of the year. Now, the thawing permafrost is causing a number of problems for people living in Alaska. Roads and utility poles are collapsing as the ground around and under them warms and soften. Also, the hard permafrost that originally prevented beaches from eroding during violent storms is now melting. People who live along Alaska's coasts are being forced to relocate. For villages on small low islands, one terrible storm could wipe out the entire community. The melting permafrost and increasing temperatures are both affecting the forests of Alaska. As the permafrost under the forests melts, insects that normally do not turn up until the warmer seasons are appearing sooner. The spruce-bark beetle, for example, is increasing in numbers as a result of warmer winter temperatures. It usually takes about two years for these beetles to grow and reproduce in. very cold weather. However, due to the increase in temperatures, spruce-bark beetles are reproducing faster and damaging as many trees in one year as they previously damaged in two. If something cannot be done to change things, Alaska's forests will not survive the turn of the century. Some scientists believe that human activity is linked to a global increase in weather temperature. Whatever the cause of rising temperatures may be, the fact remains that temperatures are warming, affecting Alaska for the worse. Horribly, this could be a preview of what will happen to the rest of the world in the next century.  According to the passage, the following are the problems caused by the melting permafrost, EXCEPT _____.

Xem chi tiết 4.5 K lượt xem 5 năm trước

Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the question. Alaska is disappearing slowly, but surely. It is estimated that since the 19505, as much as fifteen percent of Alaska's land area has disappeared. How can a whole state be disappearing? The problem is that Alaska’s glaciers are melting. The state has more than 100,000 glaciers. These glaciers account for about 75,000 square kilometers, or five percent, of the state’s area. That is an area of land larger than Ireland! According to a recent report by the US Geological Survey, ninety-nine percent of Alaska's glaciers are either retreating or diminishing. This diminishing seems mainly due to the increase in global temperatures. Since the 19605, the average year-round temperature has increased by almost 3°C. Additionally, the average winter temperature has increased by over 6°C. Presently, an estimated 100 cubic kilometers of ice is disappearing from Alaskan glaciers every year. It may be even more in the near future, as some scientists predict that the average world temperature could go up 4 to 7°C by the year 2100. Another problem facing Alaska is its thawing permafrost. Much of the land in Alaska used to be permanently frozen or frozen for most of the year. Now, the thawing permafrost is causing a number of problems for people living in Alaska. Roads and utility poles are collapsing as the ground around and under them warms and soften. Also, the hard permafrost that originally prevented beaches from eroding during violent storms is now melting. People who live along Alaska's coasts are being forced to relocate. For villages on small low islands, one terrible storm could wipe out the entire community. The melting permafrost and increasing temperatures are both affecting the forests of Alaska. As the permafrost under the forests melts, insects that normally do not turn up until the warmer seasons are appearing sooner. The spruce-bark beetle, for example, is increasing in numbers as a result of warmer winter temperatures. It usually takes about two years for these beetles to grow and reproduce in. very cold weather. However, due to the increase in temperatures, spruce-bark beetles are reproducing faster and damaging as many trees in one year as they previously damaged in two. If something cannot be done to change things, Alaska's forests will not survive the turn of the century. Some scientists believe that human activity is linked to a global increase in weather temperature. Whatever the cause of rising temperatures may be, the fact remains that temperatures are warming, affecting Alaska for the worse. Horribly, this could be a preview of what will happen to the rest of the world in the next century.  The word "relocate" in paragraph 3 is closest in meaning to _____.

Xem chi tiết 2.2 K lượt xem 5 năm trước

Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the question. Alaska is disappearing slowly, but surely. It is estimated that since the 19505, as much as fifteen percent of Alaska's land area has disappeared. How can a whole state be disappearing? The problem is that Alaska’s glaciers are melting. The state has more than 100,000 glaciers. These glaciers account for about 75,000 square kilometers, or five percent, of the state’s area. That is an area of land larger than Ireland! According to a recent report by the US Geological Survey, ninety-nine percent of Alaska's glaciers are either retreating or diminishing. This diminishing seems mainly due to the increase in global temperatures. Since the 19605, the average year-round temperature has increased by almost 3°C. Additionally, the average winter temperature has increased by over 6°C. Presently, an estimated 100 cubic kilometers of ice is disappearing from Alaskan glaciers every year. It may be even more in the near future, as some scientists predict that the average world temperature could go up 4 to 7°C by the year 2100. Another problem facing Alaska is its thawing permafrost. Much of the land in Alaska used to be permanently frozen or frozen for most of the year. Now, the thawing permafrost is causing a number of problems for people living in Alaska. Roads and utility poles are collapsing as the ground around and under them warms and soften. Also, the hard permafrost that originally prevented beaches from eroding during violent storms is now melting. People who live along Alaska's coasts are being forced to relocate. For villages on small low islands, one terrible storm could wipe out the entire community. The melting permafrost and increasing temperatures are both affecting the forests of Alaska. As the permafrost under the forests melts, insects that normally do not turn up until the warmer seasons are appearing sooner. The spruce-bark beetle, for example, is increasing in numbers as a result of warmer winter temperatures. It usually takes about two years for these beetles to grow and reproduce in. very cold weather. However, due to the increase in temperatures, spruce-bark beetles are reproducing faster and damaging as many trees in one year as they previously damaged in two. If something cannot be done to change things, Alaska's forests will not survive the turn of the century. Some scientists believe that human activity is linked to a global increase in weather temperature. Whatever the cause of rising temperatures may be, the fact remains that temperatures are warming, affecting Alaska for the worse. Horribly, this could be a preview of what will happen to the rest of the world in the next century.  The word “permafrost” in the third paragraph mostly means _____.    

Xem chi tiết 2.2 K lượt xem 5 năm trước

Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the question. Alaska is disappearing slowly, but surely. It is estimated that since the 19505, as much as fifteen percent of Alaska's land area has disappeared. How can a whole state be disappearing? The problem is that Alaska’s glaciers are melting. The state has more than 100,000 glaciers. These glaciers account for about 75,000 square kilometers, or five percent, of the state’s area. That is an area of land larger than Ireland! According to a recent report by the US Geological Survey, ninety-nine percent of Alaska's glaciers are either retreating or diminishing. This diminishing seems mainly due to the increase in global temperatures. Since the 19605, the average year-round temperature has increased by almost 3°C. Additionally, the average winter temperature has increased by over 6°C. Presently, an estimated 100 cubic kilometers of ice is disappearing from Alaskan glaciers every year. It may be even more in the near future, as some scientists predict that the average world temperature could go up 4 to 7°C by the year 2100. Another problem facing Alaska is its thawing permafrost. Much of the land in Alaska used to be permanently frozen or frozen for most of the year. Now, the thawing permafrost is causing a number of problems for people living in Alaska. Roads and utility poles are collapsing as the ground around and under them warms and soften. Also, the hard permafrost that originally prevented beaches from eroding during violent storms is now melting. People who live along Alaska's coasts are being forced to relocate. For villages on small low islands, one terrible storm could wipe out the entire community. The melting permafrost and increasing temperatures are both affecting the forests of Alaska. As the permafrost under the forests melts, insects that normally do not turn up until the warmer seasons are appearing sooner. The spruce-bark beetle, for example, is increasing in numbers as a result of warmer winter temperatures. It usually takes about two years for these beetles to grow and reproduce in. very cold weather. However, due to the increase in temperatures, spruce-bark beetles are reproducing faster and damaging as many trees in one year as they previously damaged in two. If something cannot be done to change things, Alaska's forests will not survive the turn of the century. Some scientists believe that human activity is linked to a global increase in weather temperature. Whatever the cause of rising temperatures may be, the fact remains that temperatures are warming, affecting Alaska for the worse. Horribly, this could be a preview of what will happen to the rest of the world in the next century.  According to the report by the US Geological Survey, which of the following is NOT true about Alaska?    

Xem chi tiết 2.6 K lượt xem 5 năm trước

Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the question. Alaska is disappearing slowly, but surely. It is estimated that since the 19505, as much as fifteen percent of Alaska's land area has disappeared. How can a whole state be disappearing? The problem is that Alaska’s glaciers are melting. The state has more than 100,000 glaciers. These glaciers account for about 75,000 square kilometers, or five percent, of the state’s area. That is an area of land larger than Ireland! According to a recent report by the US Geological Survey, ninety-nine percent of Alaska's glaciers are either retreating or diminishing. This diminishing seems mainly due to the increase in global temperatures. Since the 19605, the average year-round temperature has increased by almost 3°C. Additionally, the average winter temperature has increased by over 6°C. Presently, an estimated 100 cubic kilometers of ice is disappearing from Alaskan glaciers every year. It may be even more in the near future, as some scientists predict that the average world temperature could go up 4 to 7°C by the year 2100. Another problem facing Alaska is its thawing permafrost. Much of the land in Alaska used to be permanently frozen or frozen for most of the year. Now, the thawing permafrost is causing a number of problems for people living in Alaska. Roads and utility poles are collapsing as the ground around and under them warms and soften. Also, the hard permafrost that originally prevented beaches from eroding during violent storms is now melting. People who live along Alaska's coasts are being forced to relocate. For villages on small low islands, one terrible storm could wipe out the entire community. The melting permafrost and increasing temperatures are both affecting the forests of Alaska. As the permafrost under the forests melts, insects that normally do not turn up until the warmer seasons are appearing sooner. The spruce-bark beetle, for example, is increasing in numbers as a result of warmer winter temperatures. It usually takes about two years for these beetles to grow and reproduce in. very cold weather. However, due to the increase in temperatures, spruce-bark beetles are reproducing faster and damaging as many trees in one year as they previously damaged in two. If something cannot be done to change things, Alaska's forests will not survive the turn of the century. Some scientists believe that human activity is linked to a global increase in weather temperature. Whatever the cause of rising temperatures may be, the fact remains that temperatures are warming, affecting Alaska for the worse. Horribly, this could be a preview of what will happen to the rest of the world in the next century. As mentioned in the first paragraph, the glaciers in Alaska made up _____.

Xem chi tiết 2.6 K lượt xem 5 năm trước

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 23 to 27.           Coincident with concerns (23) ______ the accelerating loss of species and habitats has been a growing appreciation of the importance of biological diversity, the number of species in a particular ecosystem, to the health of the Earth and human well-being. Much has been written about the diversity of terrestrial organisms, particularly the exceptionally rich life associated tropical rain­forest habitats. Relatively little has been said, (24) _____, about diversity of life in the sea even though coral reef systems are comparable to rain forests in terms of richness of life.           An alien exploring Earth would probably (25) ______ priority to the planet's dominants - most distinctive feature - the ocean. Humans have a bias toward land (26) _____ sometimes gets in the way of truly examining global issues. Seen from far away, it is easy to realize that landmasses occupy only one-third of the Earth's surface. Given that two thirds of the Earth's surface is water and that marine life lives at all levels of the ocean, the total three-dimensional living space of the ocean is perhaps 100 times (27) _____ than that of land and contains more than 90 percent of all life on Earth even though the ocean has fewer distinct species. Question 26

Xem chi tiết 485 lượt xem 5 năm trước

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 23 to 27.           Coincident with concerns (23) ______ the accelerating loss of species and habitats has been a growing appreciation of the importance of biological diversity, the number of species in a particular ecosystem, to the health of the Earth and human well-being. Much has been written about the diversity of terrestrial organisms, particularly the exceptionally rich life associated tropical rain­forest habitats. Relatively little has been said, (24) _____, about diversity of life in the sea even though coral reef systems are comparable to rain forests in terms of richness of life.           An alien exploring Earth would probably (25) ______ priority to the planet's dominants - most distinctive feature - the ocean. Humans have a bias toward land (26) _____ sometimes gets in the way of truly examining global issues. Seen from far away, it is easy to realize that landmasses occupy only one-third of the Earth's surface. Given that two thirds of the Earth's surface is water and that marine life lives at all levels of the ocean, the total three-dimensional living space of the ocean is perhaps 100 times (27) _____ than that of land and contains more than 90 percent of all life on Earth even though the ocean has fewer distinct species. Question 25

Xem chi tiết 881 lượt xem 5 năm trước

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 23 to 27.           Coincident with concerns (23) ______ the accelerating loss of species and habitats has been a growing appreciation of the importance of biological diversity, the number of species in a particular ecosystem, to the health of the Earth and human well-being. Much has been written about the diversity of terrestrial organisms, particularly the exceptionally rich life associated tropical rain­forest habitats. Relatively little has been said, (24) _____, about diversity of life in the sea even though coral reef systems are comparable to rain forests in terms of richness of life.           An alien exploring Earth would probably (25) ______ priority to the planet's dominants - most distinctive feature - the ocean. Humans have a bias toward land (26) _____ sometimes gets in the way of truly examining global issues. Seen from far away, it is easy to realize that landmasses occupy only one-third of the Earth's surface. Given that two thirds of the Earth's surface is water and that marine life lives at all levels of the ocean, the total three-dimensional living space of the ocean is perhaps 100 times (27) _____ than that of land and contains more than 90 percent of all life on Earth even though the ocean has fewer distinct species. Question 24

Xem chi tiết 725 lượt xem 5 năm trước

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 23 to 27.           Coincident with concerns (23) ______ the accelerating loss of species and habitats has been a growing appreciation of the importance of biological diversity, the number of species in a particular ecosystem, to the health of the Earth and human well-being. Much has been written about the diversity of terrestrial organisms, particularly the exceptionally rich life associated tropical rain­forest habitats. Relatively little has been said, (24) _____, about diversity of life in the sea even though coral reef systems are comparable to rain forests in terms of richness of life.           An alien exploring Earth would probably (25) ______ priority to the planet's dominants - most distinctive feature - the ocean. Humans have a bias toward land (26) _____ sometimes gets in the way of truly examining global issues. Seen from far away, it is easy to realize that landmasses occupy only one-third of the Earth's surface. Given that two thirds of the Earth's surface is water and that marine life lives at all levels of the ocean, the total three-dimensional living space of the ocean is perhaps 100 times (27) _____ than that of land and contains more than 90 percent of all life on Earth even though the ocean has fewer distinct species. Question 23

Xem chi tiết 1.2 K lượt xem 5 năm trước

Read the following passage and blacken the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.         The history of clinical nutrition, or the study of the relationship between health and how the body takes in and utilizes food substances, can be divided into four distinct eras: the first began in the nineteenth century and extended into the early twentieth century when it was recognized for the first time that food contained constituents that were essential for human function and that different foods provided different amounts of these essential agents. Near the end of this era, research studies demonstrated that rapid weight loss was associated with nitrogen imbalance and could only be rectified by providing adequate dietary protein associated with certain foods.        The second era was initiated in the early decades of the twentieth century and might be called “the vitamin period.” Vitamins came to be recognized in foods, and deficiency syndromes were described. As vitamins became recognized as essential food constituents necessary for health, it became tempting to suggest that every disease and condition for which there had been no previous effective treatment might be responsive to vitamin therapy. At that point in time, medical schools started to become more interested in having their curricula integrate nutritional concepts into the basic sciences. Much of the focus of this education was on the recognition of deficiency symptoms. Herein lay the beginning of what ultimately turned from ignorance to denial of the value of nutritional therapies in medicine. Reckless claims were made for effects of vitamins that went far beyond what could actually be achieved from the use of them.         In the third era of nutritional history in the early 1950's to mid-1960's, vitamin therapy began to fall into disrepute. Concomitant with this, nutrition education in medical schools also became less popular. It was just a decade before this that many drug companies had found their vitamin sales skyrocketing and were quick to supply practicing physicians with generous samples of vitamins and literature extolling the virtue of supplementation for a variety of health-related conditions. Expectations as to the success of vitamins in disease control were exaggerated. As is known in retrospect, vitamin and mineral therapies are much less effective when applied to health-crisis conditions than when applied to long-term problems of under nutrition that lead to chronic health problems. The paragraph following the passage most probably discusses?

Xem chi tiết 1 K lượt xem 5 năm trước

Read the following passage and blacken the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.         The history of clinical nutrition, or the study of the relationship between health and how the body takes in and utilizes food substances, can be divided into four distinct eras: the first began in the nineteenth century and extended into the early twentieth century when it was recognized for the first time that food contained constituents that were essential for human function and that different foods provided different amounts of these essential agents. Near the end of this era, research studies demonstrated that rapid weight loss was associated with nitrogen imbalance and could only be rectified by providing adequate dietary protein associated with certain foods.        The second era was initiated in the early decades of the twentieth century and might be called “the vitamin period.” Vitamins came to be recognized in foods, and deficiency syndromes were described. As vitamins became recognized as essential food constituents necessary for health, it became tempting to suggest that every disease and condition for which there had been no previous effective treatment might be responsive to vitamin therapy. At that point in time, medical schools started to become more interested in having their curricula integrate nutritional concepts into the basic sciences. Much of the focus of this education was on the recognition of deficiency symptoms. Herein lay the beginning of what ultimately turned from ignorance to denial of the value of nutritional therapies in medicine. Reckless claims were made for effects of vitamins that went far beyond what could actually be achieved from the use of them.         In the third era of nutritional history in the early 1950's to mid-1960's, vitamin therapy began to fall into disrepute. Concomitant with this, nutrition education in medical schools also became less popular. It was just a decade before this that many drug companies had found their vitamin sales skyrocketing and were quick to supply practicing physicians with generous samples of vitamins and literature extolling the virtue of supplementation for a variety of health-related conditions. Expectations as to the success of vitamins in disease control were exaggerated. As is known in retrospect, vitamin and mineral therapies are much less effective when applied to health-crisis conditions than when applied to long-term problems of under nutrition that lead to chronic health problems. The word “skyrocketing” is closest in meaning to_________.

Xem chi tiết 836 lượt xem 5 năm trước