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Late-night DrinkingCoffee lovers beware. Having a quick "pick-me-up" cup of coffee late in the day will play havoc with your sleep. As well as being a stimulant, caffeine interrupts the flow of melatonin, the brain hormone that sends people into a sleep.Melatonin levels normally start to rise about two hours before bedtime. Levels then peak between 2 am and 4 am, before falling again. "It’s the neurohormone that controls our sleep and tells our body when to sleep and when to wake," says Maurice Ohayon of the Stanford Sleep Epidemiology Research Center at Stanford University in California. But researchers in Israel have found that caffeinated coffee halves the body’s levels of this sleep hormone.Lotan Shilo and a team at the Sapir Medical Center in Tel Aviv University found that six volunteers slept less well after a cup of caffeinated coffee than after drinking the same amount of decaf. On average, subjects slept 336 minutes per night after drinking caffeinated coffee, compared with 415 minutes after decal They also took half an hour to drop off — twice as long as usual — and jigged around in bed twice as much.In the second phase of the experiment, the researchers woke the volunteers every three hours and asked them to give a urine sample. Shilo measured concentrations of a breakdown product of melatonin. The results suggest that melatonin concentrations in caffeine drinkers were half those in decal drinkers. In a paper accepted for publication in Sleep Medicine, the researchers suggest that caffeine blocks production of the enzyme that drives melatonin production.Because it can take many hours to eliminate caffeine from the body, Ohayon recommends that coffee lovers switch to decaf after lunch. The author of this passage probably agrees that()
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Shopping at Second-hand Clothing StoresWhen 33-year-old Pete Barth was in college, shopping at Second-hand clothing stores was just something he did — "like changing the tires on his car. "He looked at his budget and decided he could save a lot of money by shopping for clothes at thrift shops."Even new clothes are fairly disposable(可丢失的)and wear out after a couple of years," Barth said. "In thrift shops, you can find some great stuff whose quality is better than new clothes".Since then, Barth, who works at a Goodwill thrift shop in the US state of Florida, has found that there are all kinds of reasons for shopping for second-hand clothing. Some people, like him, shop to save money. Some shop for a crazy-looking shirt. And some shop as a means of conserving energy and helping the environment.Pat Akins, an accountant at a Florida Salvation Army(SA)(救世军)thrift shop, said that, for her, shopping at thrift shops is a way to help the environment."When my daughter was little, we looked at it as recycling," Akins said. "Also, why pay 30 dollars for a new coat when you can get another one for a lot less"Akins said that the SA has shops all over the US— "some as big as department stores. "All of the clothes are donated(捐赠), and when they have a surplus(盈余), they’ll have "stuff a bag" specials, where customers can fill a grocery sack with clothes for only 5 or 10 dollars,Julia Slocum, 22points out, however, that the huge amount of second-hand clothing in the US is the result of American wastefulness."I’d say that second-hand stores are the result of our wasteful, materialistic culture," said Slocum, who works for a pro-conservation organization, the Center for a New American Dream. "Thrift shops prevent that waste from going to landfills (垃圾填理场); they give clothing a second life, provide cheaper clothing for those who can’t afford to buy new ones and generate(生气)income for charities. They also provide a way for the wealthy and middle classes to shed(摆脱)some of the guilt for their level of consumption.\ The word "thrift" in paragraph 1 could be best replaced by()
Scientists Develop Ways of Detecting Heart AttackGerman researchers have (1) a new generation of defibrillators and early warning software aimed at offering heart patients greater protection (2) sudden death from cardiac arrest.In Germany alone around 100,000 people die annually as a result of cardiac arrest and many of these cases (3) by disruption to the heart’s rhythm. Those most at risk are Patients who have (4) suffered a heart attack and for years the use of defibrillators has proved useful in diagnosing (5) disruptions to heart rhythms and correcting them automatically by intervening within seconds. These devices (6) a range of functions such as that of pacemaker.Heart specialists at Freiburg’s University Clinic have now achieved a breakthrough with all implanted defibrillator (7) of generating a six-channel electrocardiogram(ECG) within the body. This integrated system allows early diagnosis of (8) blood-flow problems and a pending heart attack. It will be implanted in patients for the first time this year. Meanwhile, researchers at the Fraunhofer Institute for Applied Mathematics in Kaiserslautern have developed new computer software that renders the evaluation of ECG data (9) .The overwhelming (10) of patients at risk will not have an implanted defibrillator and must for this reason undergo regular ECGs. "Many of the current programs only (11) into account a linear correlation of the data. We are, however, making use (12) a non-linear process that reveals the chaotic patterns of heart beats as an open and complex system." Hagen Knaf says." (13) changes in the heart beats over time can be monitored and individual variations in patients taken into account." An old study of ECG data, based (14) 600 Patients who had suffered a subsequent heart attack, enabled the researchers to compare risks and to show (15) the new software evaluates the data considerably better. 54()
Scientists Develop Ways of Detecting Heart AttackGerman researchers have (1) a new generation of defibrillators and early warning software aimed at offering heart patients greater protection (2) sudden death from cardiac arrest.In Germany alone around 100,000 people die annually as a result of cardiac arrest and many of these cases (3) by disruption to the heart’s rhythm. Those most at risk are Patients who have (4) suffered a heart attack and for years the use of defibrillators has proved useful in diagnosing (5) disruptions to heart rhythms and correcting them automatically by intervening within seconds. These devices (6) a range of functions such as that of pacemaker.Heart specialists at Freiburg’s University Clinic have now achieved a breakthrough with all implanted defibrillator (7) of generating a six-channel electrocardiogram(ECG) within the body. This integrated system allows early diagnosis of (8) blood-flow problems and a pending heart attack. It will be implanted in patients for the first time this year. Meanwhile, researchers at the Fraunhofer Institute for Applied Mathematics in Kaiserslautern have developed new computer software that renders the evaluation of ECG data (9) .The overwhelming (10) of patients at risk will not have an implanted defibrillator and must for this reason undergo regular ECGs. "Many of the current programs only (11) into account a linear correlation of the data. We are, however, making use (12) a non-linear process that reveals the chaotic patterns of heart beats as an open and complex system." Hagen Knaf says." (13) changes in the heart beats over time can be monitored and individual variations in patients taken into account." An old study of ECG data, based (14) 600 Patients who had suffered a subsequent heart attack, enabled the researchers to compare risks and to show (15) the new software evaluates the data considerably better. 65()
孙某，男，61岁。有长期吸烟史，近2-3个月来声音嘶哑，咳嗽，少量黏痰，偶或痰中带血，低热，伴身体乏力。1年来曾有肺结核接触史。X线显示：右肺上野有-2cm×3cm密度较高的球形阴影。最可能的诊断是（）
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