Antidepressant(抗忧郁)drugs such as Prozac were viewed in the early 1900's as wonder pills that would remove depressive blues for good. But in the past five years, growing scientific evidence has shown these drugs work for only a minority of people. And now a research journal says that these antidepressants can make many patients' depression worse. This alarming suggestion centres on the very chemical that is targeted by antidepressants-serotonin(血清素). Drugs such as Prozac are known as selective serotonin re-uptake inhibitors(or SSRIs). Their aim is to increase the level of this  “feel-good” chemical in the brain.

But the new research, published in the journal Frontiers In Evolutionary Psychology, points out that serotonin is like a chemical Swiss Army knife, performing a very wide range of jobs in the brain and body. And when we start changing serotonin levels purposely, it may cause a wide range of unwanted effects. These can include digestive problems and even early deaths in older people, according to the study's lead researcher Paul Andrews. “ We need to be much more cautious about use of these drugs,” says Andrews, an assistant professor of evolutionary psychology at McMaster University in Ontario, Canada.

Previous research has suggested that the drugs provide little benefit for most people with mild depression, and actively help only a few of the most severely depressed. Famous psychologist Irving Kirsch has found that for many patients, SSRIs are no more effective than a placebo pill. A research in 2010 on Danish children found a small, but significant, increase in the risk of heart problems among babies whose mothers had used SSRIs in early pregnancy. The key to understanding these side-effects is serotonin, says Andrews. Serotonin is also the reason why patients can often end up feeling still more depressed after they have finished a course of SSRI drugs. He argues that SSRI antidepressants disturb the brain, leaving the patient an even greater depression than before.

“After long use, when a patient stops taking SSRIs, the brain will lower its levels of serotonin production,” he says, adding that it also changes the way receptors in the brain respond to serotonin, making the brain less sensitive to the chemical. These changes are believed to be temporary, but studies indicate that the effects may continue for up to two years.

Most disturbingly of all, Andrews' review features three recent studies which, he says , show that elderly antidepressant users are more likely to die earlier than non-users, even after taking other important variables into account. One study, published in the British Medical Journal last year, found patients given SSRIs were more than 4 per cent more likely to die in the next year than those not on the drugs.

“Serotonin is an ancient chemical,” says Andrews. “It is regulating many different processes, and when you disturb these things, you can expect that it is going to cause some harm.”

Stafford Lightman, professor of medicine at the University of Bristol, and a leading UK expert in brain chemicals and hormones, says Andrews’ review highlights some important problems, yet it should also be taken with a pinch of salt. “This report is doing the opposite of what drug companies do,” he says. “Drug companies selectively present all the positives in their research, while this search selectively presents all the negatives that can be found. Nevertheless, Andrews' study is useful in that it is always worth pointing out that there is a downside to any medicine. ” Professor Lightman adds that there is still a great deal we don't know about SSRIs-not least what they actually do in our brains.

When it comes to understanding why the drugs work only for a limited part of patients, U.S.  scientists think they might now have the answer. They think that in many depressed patients, it’s not only the lack of feel-good serotonin causing their depression, but also a failure in the area of the brain that produces new cells throughout our lives. This area, the hippocampus, is also responsible for regulating mood and memory. Research suggests that in patients whose hippocampus has lost the ability to produce new cells, SSRIs do not bring any benefit.

1.According to paragraph 2, serotonin, like a chemical Swiss Army knife, can             .

A. make many patients' depression worse

B. cause a wide range of unwanted effects

C. affect human body and brain in various ways

D. provide little benefit for most depressed people

2.In Stafford Lightman's opinion,                     .

A. drug companies don't know the negative effect of antidepressants

B. Andrews focused on different things from the drug companies

C. scientists have found what SSRIs do in the brain

D. Andrews' research has no medical value

3.Which of the following is TRUE about SSRIs?

A. They are used to increase the “feel-good” medical in the brain.

B. They can work even when the hippocampus can't produce new cells.

C. They create a risk of heart problems in pregnant women.

D. They are responsible for controlling mood and memory.

4.What is the text mainly about?

A. The aim of drug companies

B. The function of SSRIs

C. The side-effects of antidepressants

D. The cause of depression

 

She took up skating at age 85, made her first movie appearance at age 114, and held a concert in the neighborhood on her 121st birthday.

      When it comes to long life, Jeanne Calment is the world’s recordholder. She lived to the ripe old age of 122. So is 122 the upper limit to the human life span(寿命)? If scientists come up with some sort of pill or diet that would slow aging, could we possibly make it to 150-or beyond?

      Researchers don’t entirely agree on the answers. “Calment lived to 122, so it wouldn’t surprise me if someone alive today reaches 130 or 135, ”says Jerry Shay at the University of Texas.

      Steve Austad at the University of Texas agrees. “People can live much longer than we think, ”he says. “Experts used to say that humans couldn’t live past 110. When Calment blew past that age, they raised the number to 120. So why can’t we go higher? ”

      The trouble with guessing how old people can live to be is that it’s all just guessing. “Anyone can make up a number, ”says Rich Miller at the University of Michigan. “Usually the scientist who picks the highest number gets his name in Time magazine. ”

      Won’t new anti-aging techniques keep us alive for centuries? Any cure, says Miller, for aging would probably keep most of us kicking until about 120. Researchers are working on treatments that lengthen the life span of mice by 50 percent at most. So, if the average human life span is about 80 years, says Miller, “adding another 50 percent would get you to 120. ”

      So what can we conclude from this little disagreement among the researchers? That life span is flexible(有弹性的), but there is a limit, says George Martin of the University of Washington. “We can get flies to live 50 percent longer, ”he says. “But a fly’s never going to live 150 years. ”Of course, if you became a new species (物种), one that ages at a slower speed, that would be a different story, he adds.

      Does Martin really believe that humans could evolve (进化)their way to longer life? “It’s pretty cool to think about, ”he says with a smile.

1. What does the story of Jeanne Calment prove to us?

A.People can live to 122.

B.Old people are creative.

C.Women are sporty at 85.

D.Women live longer than men.

2. According to Steve Austad at the University of Texas, ______.

A.the average human life span could be 110

B.scientists cannot find ways to slow aging

C.few people can expect to live to over 150

D.researchers are not sure how long people can live

3. Who would agree that a scientist will become famous if he makes the wildest guess at longevity?

A.Jerry Shay.                            B.Steve Austad

C.Rich Miller                            D.George Martin

4. What can we infer from the last three paragraphs?

A.Most of us could be good at sports even at 120.

B.The average human life span cannot be doubled

C.Scientists believe mice are aging at a slower speed than before.

D.New techniques could be used to change flies into a new species

 

Something in chocolate could be used to stop coughs and lead to more effective medicines, say UK researchers.

Their study found that theobromine(可可碱), found in cocoa, was nearly a third more effective in stopping coughs than codeine, which was considered the best cough medicine at present.

The Imperial College London researchers who published their results online said the discovery could lead to more effective cough treatment. “While coughing is not necessarily harmful it can have a major effect on the quality of life, and this discovery could be a huge step forward in treating this problem,” said Professor Peter Barnes.

Ten healthy volunteers were given theobromine, codeine or placebo, a pill that contains no medicine, during the experiment. Neither the volunteers nor the researchers knew who received which pill. The researchers then measured levels of capsaicin, which is used in research to cause coughing and as a sign of how well the medicines are stopping coughs.

The team found that, when the volunteers were given theobromine, the capsaicin needed to produce a cough was around a third higher than in the placebo group. When they were given codeine they needed only slightly higher levers of capsaicin to cause a cough compared with the placebo.

The researchers said that theobromine worked by keeping down a nerve activity(神经活动), which cause coughing. They also found that unlike some standard cough treatments, theobromine caused no side effects such as sleepiness.

1.According to Professor Barnes, theobromine ______.

A. cannot be as effective as codeine

B. can be harmful to people’s health

C. cannot be separated from chocolate

D. can be a more effective cure for coughs

2.What was used in the experiment to cause coughing?

A. Theobromine.                          B. Codeine.             C. Capsaicin.                    D. Placebo.

3.We learn from the text that volunteers in the experiment _____.

A. were patients with bad coughs

B. were divided into the three groups

C. received standard treatments

D. suffered little side effects

4.Which of the following would be the best title for the text?

A. Codeine: A New Medicine

B. Chocolate May Cure Coughs

C. Cough Treatment: A Hard Case

D. Theobromine Can Cause Coughs

 

The following are four kinds of medicine. How to use the medicine is very important. Never take some by mistake.

   Take the medicine with water, followed by one tablet every eight hours, as required. For further nighttime and early morning, take two tablets at bedtime. Do not take more than six tablets in 24 hours. For children between six and twelve years old, give half the adult dosage(剂量). For children under six years old, go to your doctor for advice. Reduce dosage if nervousness, restlessness or sleeplessness takes place.

 

   Each pill of the medicine taken three times every day for fourteen-year- olds. As usual, a pill at 6:00a.m. before breakfast, one before 11:00 and one before sleep. Not for children under six years old and old persons with heart attack.

 

   The medicine for a person with a fever. Once two pills a day before sleep for adults. Don’t take the medicine without fever. Half for children under 12 years old. For children with a high fever, go to see a doctor at once.

 

   The medicine taken three times a day, once five pills for adults with a cold. Half of the pills for children under 14 years old. Take the medicine before breakfast, lunch, supper or before sleep.

1. If a little child under six has a fever, it’s suggested that he ________.

A. take two tablets before sleep                B. stop to take another pill

C. take one tablet before sleep                 D. go to see a doctor

2.Obviously a kind of medicine mentioned above isn’t proper for ________, judging from the information.

A. children over twelve years old               B. some adults of 18 years old

C. some old persons with heart attack           D. neither adults nor children

3.When an adult has a cold, he had better __________.

A. have as many as fifteen pills a day          B. have twice a day

C. have four times a day                        D. have nine pills a day

4. How many kinds of medicine can be taken by children of seven years old?

A. Two kinds.       B. Three kinds.      C. None.         D. Four kinds.

 

Something in chocolate could be used to stop coughs and lead to more effective medicines, say UK researchers.

Their study found that theobromine, found in cocoa, was nearly a third more effective in stopping coughs than codeine, which was considered the best cough medicine at present.

The Imperial College London researchers who published their results online said the discovery could lead to more effective cough treatment. “While coughing is not necessarily harmful(有害的) it can have a major effect on the quality of life, and this discovery could be a huge step forward in treating this problem,” said Professor Peter Barnes.

Ten healthy volunteers(志愿者) were given theobromine, codeine or placebo, a pill that contains no medicine, during the experiment. Neither the volunteers nor the researchers knew who received which pill. The researchers then measured levels of capsaicin, which is used in research to cause coughing and as a sign of how well the medicine are stopping coughs.

The team found that, when the volunteers were given theobromine, the capsaicin need to produce a cough was around a third higher than in the placebo group. When they were given codeine they need only slightly higher levers of capsaicin to cause a cough compared with the placebo.

The researchers said that theobromine worked by keeping down a verve activity(神经活动), which cause coughing. They also found that unlike some standard cough treatments, theobromine caused no side effects such as sleepiness.

1.According to Professor Barnes, theobromine ______.

A.cannot be as effective as codeine

B.can be harmful to people’s health

C.cannot be separated from chocolate

D.can be a more effective cure for coughs

2.What was used in the experiment to cause coughing?

A.Theobromine.

B.Codeine.

C.Capsaicin.

D.Placebo.

3.We learn from the text that volunteers in the experiment _____.

A.were patients with bad coughs

B.were divided into the three groups

C.received standard treatments

D.suffered little side effects

4.Which of the following would be the best title for the text?

A.Codeine: A New Medicine

B.Chocolate May Cure Coughs

C.Cough Treatment: A Hard Case

D.Theobromine Can Cause Coughs

 

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