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单选题Feeling anxious? Your mood may actually change how your dinner tastes, making the bitter and salty flavors recede, according to new research. This link between the chemical balance in your brain and your sense of taste could one day help doctors to treat depression. There are currently no on-the-spot tests for deciding which medication will work best in individual patients with this condition. Researchers hope that a test based on flavor detection could help doctors to get more prescriptions right first time. It has long been known that people who are depressed have lower-than-usual levels of the brain chemicals serotonin or noradrenaline, or in some cases both. Many also have a blunted sense of taste, which is presumably caused by changes in brain chemistry. To unpick the relationship between the two, Lucy Donaldson and her colleagues at the University of Bristol, UK, gave 20 healthy volunteers two antidepressant drugs, and checked their sensitivity to different tastes. The drug that raised serotonin levels made people more sensitive to sweet and bitter tastes, the team reports in the Journal of Neuroscience. The other, which increased noradrenaline, enhanced recognition of bitter and sour tastes. In healthy people, volunteers whose anxiety levels were naturally higher were less sensitive to bitter and salty tastes. "What hasn't been done beore is to look precisely at which tastes are affected in depression," says Donaldson. Now the results are in, "we can discriminate between the chemicals and the tastes that seem to be altered," she says. Testing sensitivity to sweet and sour tastes could potentially help doctors to pick up on which chemicals are dipping, guiding them when choosing which drug to rectify the problem. Currently, doctors rely on physical and emotional symptoms to make a best guess at an individual's imbalance, prescribe a drug and wait about a month to check on any improvement. Good doctors have about a 60-80% success rate in selecting the right drug the first time, says psychiatrist Jan Melichar, a co-author on the paper. Are there any decent tests for prescribing drugs for depression? "No. We do a best guesstimate," says Melichar. "I'm excited by this finding because in 3, 5 or 7 years we could have a simple taste test. " Next, the team plans to perform similar tests in depressed people, and in healthy volunteers given another brain chemical called tryptophan. This chemical would lower the healthy subjects' levels of serotonin, as actually happens in depressed patients. The work has also generated interest from flavor houses--companies that develop chemicals for the food and drink industry--who are interested in making foods taste just as sweet with half the amount of sugar. "Theoretically there would be the possibility of enhancing your meal with drugs that affect brain chemicals so that things would taste better--you couid have a 'designer taste tablet'," Donaldson says.

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单选题哪部医学著作将呃逆分为外感、内伤两大类

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单选题症见寒战，继而高热，反复发作，每三日一次，多见于A．少阳病B．湿温C．疟疾D．瘟疫

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单选题A．问病人社会经历B．问发病的时间与诱因C．问素体健康状况D．问病人的饮食嗜好

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单选题以脉位深沉为特征的脉是( )(2010年第20题)

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单选题Under pressure from animal welfare groups, two national science teachers associations have adopted guidelines that ban classroom experiments harming animals. The National Association of Biology Teachers and the National Science Teachers Association hope to end animal abuse in elementary and secondary schools and, in turn, discourage students from mishandling animals in home experiments and science fair projects. Animal welfare groups are apparently most concerned with high school students experimenting with animals in extracurricular projects. Barbara Orlans, President of the Scientists' Center for Animal Welfare, said that students have been performing surgery at random, testing known poisonous substances, and running other pathology experiments on animals without even knowing normal physiology. At one science fair, a student cut off the leg and tail of a lizard to demonstrate that only the tail can regenerate, she said. In another case, a student bound sparrows, starved them and observed their behavior. "The amount of abuse has been quite horrifying," Orlans said. Administrators of major science fairs are short-tempered over the teachers' policy change and the impression it has created. '"The teachers were sold a bill of goods by Barbara Orlans," said Thurman Grafton, who heads the rules committee for the International Science and Engineering Fair. "Backyard tabletop surgery is just nonsense. The new policies throw cold water on students' inquisitiveness," he said. Grafton said he wouldn't deny that there hasn't been animal abuse among projects at the international fair, but he added that judges reject contestants who have unnecessarily injured animals. The judges have a hard time monitoring local and regional fairs that may or may not choose to comply with the international fair's rules that stress proper care of animals, Grafton said. He said that several years ago, the Westinghouse Science Talent Search banned harmful experiments to animals when sponsors threatened to cancel their support after animal welfare groups lobbied for change. The teachers adopted the new policies also to fend off proposed legislation--in states including Missouri and New York that would restrict or prohibit experiments on animals. Officials of the two teachers organizations say that they don't know how many animals have been abused in the classroom. On the one hand, many biology teachers are not trained in the proper care of animals, said Wayne Moyer, executive director of the biology teachers' association. On the other, the use of animals in experiments has dropped in recent years because of school budget cuts. The association may set up seminars to teach better animal care to its members.

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单选题A．干咳无痰，或痰少而黏 B．身热恶寒C．两者均有 D．两者均无(1995年第105，106题)

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单选题提出了独取寸口诊脉法的是

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单选题下列哪项表现为语言错乱。语后自知言错

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单选题Young girls at high risk for depression appear to have a malfunctioning reward system in their brains, a new study suggests. The finding comes from research that (1) a high-risk group of 13 girls, aged 10 to 14, who were not depressed but had mothers who (2) recurrent depression and a low-risk group of 13 girls with no (3) or family history of depression. Both groups were given MRI brain (4) while completing a task that could (5) either reward or punishment. (6) with girls in the low-risk group, those in the high-risk group had (7) neural responses during both anticipation and receipt of the reward. (8) , the high-risk girls showed no (9) in an area of the brain called the dorsal anterior cingulated cortex(背侧前扣带皮质), which is believed to play a role in (10) past experiences to assist learning. The high-risk girls did have greater activation of this brain area (11) receiving punishment, compared with the other girls. The researchers said that this suggests that high-risk girls have easier time (12) information about loss and punishment than information about reward and pleasure. "Considered together with reduced activation in the striate(纹状体的)areas commonly observed (13) reward, it seems that the reward-processing system is critically (14) in daughters who are at elevated risk for depression, (15) they have not yet experienced a depressive (16) , " wrote Ian H. Gotlib, of Stanford University, and his colleagues. " (17) , hmgitudinal studies are needed to determine whether the anomalous activations (18) in this study during the processing of (19) and losses are associated with the (20) onset of depression," they' concluded. The study was published in the April of the Archives of General Psychiatry.

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单选题A．膻中B．气海C．期门D．章门

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单选题A．清稀而多泡沫 B．白滑量多，易于咯出 C．痰少而黏，难于咯出 D．色黄质黏，甚则结块

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