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单选题
有关褪黑素（Melatonin），错误的是（ ）。
A
对睡眠障碍可能有改善作用
B
对时差症状的治疗可能有效
C
是脑白金的主要成分
D
是松果体分泌的激素
E
经FDA批准为处方药
参考答案
参考解析
解析：
褪黑素，又名黑素细胞凝集素，俗称为脑白金，主要是由哺乳动物和人类的松果体产生的一种胺类激素。褪黑素参与调节睡眠—觉醒周期，可以改善时差症状和睡眠时相延迟综合征。
褪黑素，又名黑素细胞凝集素，俗称为脑白金，主要是由哺乳动物和人类的松果体产生的一种胺类激素。褪黑素参与调节睡眠—觉醒周期，可以改善时差症状和睡眠时相延迟综合征。
更多 “单选题有关褪黑素（Melatonin），错误的是（ ）。A 对睡眠障碍可能有改善作用B 对时差症状的治疗可能有效C 是脑白金的主要成分D 是松果体分泌的激素E 经FDA批准为处方药” 相关考题
考题
共用题干
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 be-tween 2 a.m.and 4 a. m.,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 vol- unteers slept less well after a cup of caffeinated coffee than after drinking the same amount of de-caf（脱因咖啡）.On average , subjects slept 336 minutes per night after drinking caffeinated cof-fee,compared with 415 minutes after decaf. 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 decaf 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. What does the experiment mentioned in Paragraph 4 prove?A: There are more enzymes in decaf drinkers' urine sample.B: There are more melatonin concentrations in caffeine drinkers' urine sample.C: Decaf drinkers produce less melatonin.D: Caffeine drinkers produce less sleep hormone.
考题
梅拉多宁别名褪黑素，是人脑部深处“松果体”分泌的一种胺类激素。其分泌是有昼夜节律的。夜幕降临后，随着光刺激减弱，体内褪黑素的分泌水平也相应增高。随着年龄增长，松果体萎缩直至钙化，造成生物钟的节律性减弱或消失，特别是35岁以后，体内自身分泌的褪黑素明显下降，导致睡眠紊乱以及一系列功能失调，________________。因此，从体外补充褪黑素，可使体内的褪黑素水平维持在年轻状态，不仅能提高睡眠质量，更重要的是改善身体机能状态，延缓衰老的进程。
填入划横线部分最恰当的一项是：A.褪黑素水平降低、睡眠减少是人类脑衰老的重要标志之一
B.由此可见，褪黑素在人类延缓衰老方面有重要的作用
C.夜间褪黑素水平的高低直接影响到睡眠的质量
D.褪黑素的分泌成了人进入老年状态的标志之一
考题
共用题干
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 be-tween 2 am and 4 am,before falling again."It's the neurohormone that controls our sleep 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 caf feinated 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 vol-unteers slept less well after a cup of caffeinated coffee than after drinking the same amount of de-caf. On average,subjects slept 336 minutes per night after drinking caffeinated coffee,compared with 415 minutes after decaf. They also took half an hour to drop offtwice 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 decaf 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 mentions"pick-me-up" to indicate that______.A: melatonin levels need to be raisedB: neurohormone can wake us upC: coffee is a stimulantD: decaf is a caffeinated coffee
考题
填空题褪黑素的节律性分泌可分为（）、（）和（）。
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