Dietary studies have suggested that people who consume large amounts of vitamin A in foods, multi vitamins, or both are more likely to suffer hip fractures than are people who ingest modest amounts. New evidence bolsters these findings. Researchers have now correlated men"s blood concentrations of vitamin A with a later incidence of broken bones: a comparison that avoids the vagaries that plague diet-recall studies. Taken together, the new work and the diet studies raise knotty questions about the maximum amount of vitamin A that a person can safely ingest each day, says study coauthor Karl Michasson, an orthopedic surgeon at University Hospital in Uppsala, Sweden. He and his colleagues report the new findings in Jan. 23 New England Journal of Medicine. In the United States, the average daily intake of vitamin A through food, specially fish, eggs, and meat, is roughly 2,600 IU (international units) for men, and many multi-vitamins contain 5,000 IU. The US Institute of Medicine recommends that people get 2,300 to 3,000 IU of vitamin A each day and sets the safe upper limit around 10,000 IU. "I believe tiffs upper level should be lowered," Michasson says. When he and his colleagues gave the men dietary questionnaires, they learned that men ingesting as little as 5,000 IU of vitamin A per day were more prone to fractures than were men getting less. Manufacturers should lower the amount of vitamin A in multi-vitamin tablets and fortified foods, such as cereals, says Michasson. The new study began in the early 1970s when researchers stored blood samples from 2,047 men about 50 years old. Since then, 266 of the men have had at least one bone fracture. After dividing the men into five equal groups according to their blood vitamin A concentrations, the researchers found that men in the top group were nearly twice as likely as those in the middle group to have broken a bone. The correlation was particularly strong with fractures of the hip. "I think it"s pretty conclusive now that there"s a bad effect of vitamin A supplementation," says Margo A. Denke, an endocrinologist at the University of Texas Southwestern Medical Center in Dallas. Elderly people may be at special risk because they"re slow to clear the vitamin from their bodies. Studies of animals have established that excess vitamin A stimulates the formation of cells that dissolve bone. However, since some vitamin A is necessary to maintain good eyesight and general health, Denke and Michasson agree that fully fortified foods and supplements should remain available in countries where poor nutrition puts people at risk of a vitamin A deficiency. Michasson may NOT support the idea to
A. lower the recommended safe upper limit of vitamin A amount.
B. produce vitamin A supplement pills with less vitamin A in them.
C. prevent people from eating cereals in their everyday meals.
D. lower the amount of vitamin A in fortified food and supplements.
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Humans not only love eating ice cream, they enjoy (1)_____ it to their pets. Market studies show that two thirds of all dog owners give ice cream to the dogs. (2)_____, says William Tyznik, an expert in animal nutrition at Ohio State University, ice cream is not good for dogs. "It has milk sugar in it," he says, "which dogs cannot (3)_____ very well." (4)_____ by that knowledge but aware of the desire of dog owners to (5)_____ their companions, Tyznik invented a new frozen treat for dogs that, he says, is more nutritious than ice cream—and as much (6)_____ to eat. The product, called Frosty Paws, is made of a liquid byproduct of cheese and milk with the sugar (7)_____. Frosty Paws also contains refined soy flour, water, vegetable oil, vitamins and minerals. It (8)_____ Tyznik, who has also invented a horse food (called Tizwhiz) and (9)_____ dog food (named Tizbits), three years to (10)_____ the Frosty Paws formulas, and two (11)_____ to commercialize it. After losing $25,000 trying to market the invention himself, Tyznik sold the rights to Associated Ice Cream of Westerville, Ohio, which makes the product and (12)_____ it in cups. Tyznik claims that Frosty Paws has been tested (13)_____ and that "dogs love it". Of 1,400 dogs that have been (14)_____ the product, he says, 89 percent took it on the first (15)_____. Three out of four (16)_____ it to Milk-Bone or sausages. The product, which will be (17)_____ in the ice cream section of supermarkets, comes in (18)_____ of three or four cups, costing about $1.79. What would happen (19)_____ a human should mistake Frosty Paws for real ice cream Nothing, says Tyznik. It"s (20)_____, but frankly, he says, it won"t taste very good.
A. Surprisingly
B. Unfortunately
C. Therefore
D. Initially
City Hall"s office is currently having a ______ to feed and clothe the homeless. Non-perishable food goods are welcome. Canned goods are ideal. We accept clothing of any kind ______ it is wearable. Cleaning the clothes before delivery would be appreciated. We will provide receipts for all donations to be used for tax ______.Donations will be accepted at City Hall"s office. If you need directions or would like more information, please call 343-356-2736.
A. refunded
B. refunds
C. refundable
D. refunding
Over the last twenty years, scholarly and popular writers have analyzed and celebrated the worlds of leisure and entertainment in the burgeoning cities of mid-nineteenth-century America, greatly expanding the literature on these subjects. They have found an enthusiastic readership by offering glimpses of modes of leisure, performance, and charlatanism that passed from the scene in the early 20th century, indicating how lively they were and how comparatively impoverished our own entertainment choices have become in an era dominated by corporate electronic media. Many scholars have been lured into a fascination with the extinct demimonde of dime museums, exhibition hails, saloons, and industrial exhibitions. During this period entertainment relied upon artful deception, comparable in importance to such contemporary forms of amusement as minstrelsy and melodrama. The cultural activities were forms of representational play in which spectators are caused to doubt their perceptions and judgment. Entertainments that tricked, or duped the paying public flourished in America"s cities in the 19th century. What distinguished these cohorts of entertainers, was not their ability to perpetrate fraud but that they understood the dynamics of a new urban audience that enjoyed distinguishing the genuine from the fake and the authentic from the concocted. The willing audience for artful deceptions maintained a double consciousness in which it simultaneously marveled at the qualities of the object or action displayed while enjoying the act of appraising the quality, audacity, and performance of the deception. By offering semiotic analyses of a range of Victorian performances, we learn there was more to these exhibitions than appeared at first viewing. The tricks and lures of these entertainers deserve a more than marginal position in American cultural history. It can be learned that the types of entertainment of mid-nineteenth century
A. have become increasingly popular among scholars since the 80"s.
B. were so sophisticated that audiences couldn"t understand.
C. actually involved very little actual fraud and double consciousness.
D. discouraged people from suspecting their perceptions.
Eight months after Sep. 11, it is becoming increasingly apparent that various arms of the US government had pieces of information that, if put together, might have provided sketchy advance warning of the terrorist strikes to come. The White House now acknowledges, that the CIA told President Bush in August that suspected members of A1 Qaeda had discussed the hijacking of airplanes. At the same time, FBI agents were increasingly suspicious of some Middle Eastern men training at US flight schools. Yet the US government didn"t pay attention to this information. "There are always these little indicators that come in—of one sort or another—that don"t get enough decibels to receive attention," say former CIA Director Stansfield Turner. "The possibility of a traditional hijacking—in the pre-9.11 sense—has long been a concern of the government," White House spokesman Ari Fleischer said. But "this was a new type of attack that was not foreseen." In deed, he said the warnings did not suggest commercial airliners would be used as missiles and that the general assumption was that any attack would occur abroad, not in the US. Still, the White House says it did quietly alert several government agencies to the threat. Meanwhile, FBI agents were getting hints of the terrible plot. A classified memo drafted by the bureau reportedly warned in blunt language that Osama bin Laden might be linked to Middle Eastern men taking lessons at US flight schools. Mr. Turner sees this as a painful and avoidable mistake. The basic reason for the lack of coordination and communication is "a very large intelligence bureaucracy that is very compartmentalized," says Charles Penia, a senior defense analyst at the Cato Institute. Today, the disclosures raise a crucial question: Have recent reforms boosted Washington"s ability to pull together information from its many agencies—and thus disrupt future attacks Indeed, since Sep. 11, the government has struggled to improve coordination. One change: FBI data is now merged with CIA intelligence in the president"s daily briefing. Another: A new command center near Washington was set up by White House Homeland Security. It"s one place the CIA, the FBI, the Defense Intelligence Agency, and others are able to coordinate and share information. It"s not clear yet whether they actually will. Which conclusion can NOT be drawn from the first three paragraphs
A. The U.S. government should be partly responsible for 9.11.
B. 9.11 event could have been avoided.
C. The U.S. government should have paid more attention to the warnings.
D. The CIA is inevitably responsible for its incorrect information.