A new study has found no evidence that sunscreen, commonly used to reduce the risk of skin cancer, actually increases the risk.
Researchers from the University of Iowa based their findings on a review of 18 earlier studies that looked at the association between sunscreen use and melanoma (黑素瘤).They said that they found faults in studies that had reported associations between sunscreen use and higher risk of melanoma.
Most health experts believe that by protecting the skin from the harmful effects of the sun, sunscreen helps prevent skin cancer, which is increasing in incidence (發(fā)生率) faster than any other cancer in the United States.
But questions has been raised about sunscreen and whether it may has opposite effect, perhaps by allowing people to remain exposed to the sun longer without burning.
The researchers said that among the problems with some earlier studies is that they often failed to take into account that those people most at risk for skin cancer--- people with fair skin and freckles (雀斑), for example--- are more likely to use sunscreen.As a result, it may appear that sunscreen users get cancer more often.
The studies, which generally relied on volunteers to recall their sunscreen use, were also unable to prove how well the products had been applied, said the new study.
小題1:People with fair skin and freckles         .
A.seldom use sunscreen
B.a(chǎn)re more in danger of skin cancer
C.can be free from the harm of the sun
D.often expose themselves to the sun
小題2:We can learn from the passage that         .
A.sunscreen users get skin cancer more often
B.the volunteers have proved the effect of sunscreen
C.the new study was based on the experiences of volunteers
D.the number of skin cancer patients is increasing in America
小題3:Which of the following can be the best title for this passage?
A.Sunscreen to Prevent Skin Cancer
B.Sunscreen to Increase Skin Cancer
C.Skin Cancer Caused by Sunscreen
D.Skin Cancer Caused by Freckles
練習(xí)冊(cè)系列答案
相關(guān)習(xí)題

科目:高中英語(yǔ) 來(lái)源:不詳 題型:完形填空

Directions: Complete the following passage by using the words in the box. Each word can only be used once. Note that there is one word more than you need.
Some people with autism(孤獨(dú)癥) have __小題1:___ experts with their outstanding memories, mathematical skills or musical talent. Now scientists have found that the genes thought to cause autism may also confer(給予) mathematical, musical and other skills on people without the condition.
The finding has _小題2:___ from a study of autism among 378 Cambridge University students, which found the condition was up to seven times more common among mathematicians than students in other fields.
If __小題3:__, it could explain why autism - a ___小題4:___that makes it hard to communicate with, and relate to, others ─ continues to exist in all types of society. It suggests the genes responsible are usually ___小題5:__, causing the disease only if present in the wrong combinations. “Our understanding of autism is undergoing a ___小題6:__,” said Professor Simon Baron-Cohen, director of the autism research centre at Cambridge, who led the study.
“It seems clear that genes play a significant role in the causes of autism and that those genes are also ___小題7:__ to certain intellectual skills.”
Scientists have long been interested by the apparent ___小題8:__ between autism and intellectual gifts in specific fields. This has made autism a hot topic in popular culture, from films such as Rain Man, which starred Dustin Hoffman and Tom Cruise, to books such as The Curious Incident of the Dog in the Nighttime.
Temple Grandin, 61, was diagnosed(診斷) with autism as a child and is now professor of animal sciences at Colorado State University. She said: “People with autism have played a vital role in human evolution and culture. Scientists such as Isaac Newton and Albert Einstein show every __小題9:___ of having been autistic. The world owes a great deal to those who design and programme computers, many of whom show autistic traits.”

查看答案和解析>>

科目:高中英語(yǔ) 來(lái)源:不詳 題型:閱讀理解

Have you ever been in a situation, where you felt uneasy because of something you think you may have forgotten to do or perhaps a feeling that you annoyed someone whom you wanted to get along with really well. If you have experienced such feelings and worse on a regular basis, then you most probably are a victim of anxiety attacks.
All of us, to some extent, have experienced anxiety at different levels. There are somethings you may know about anxiety, and some things that you may not be familiar with. So in order to be prepared for your unexpected feeling of anxiety, you need to get to know what anxiety is before it escalates into a panic attack.
Anxiety is simply the feeling of discomfort, uneasiness or fear of what may eventually happen resulting from an imagined, or a real threatening condition. On the extreme end panic attacks can occur due to heightened(增加) feelings of anxiety.
There are two main symptoms(癥狀) during an anxiety / panic attack and these are physical and emotional symptoms. Physical symptoms include difficulty in breathing, shaking, direct feeling of heat, rapid heartbeat and tiredness while emotional symptoms deal with worrying, depression, fear, and lack of focus.
In spite of the negative impression we have for anxiety, it is not dangerous in any way whatever. The feeling of anxiety is not bad, in fact it’s more of a defensive feeling which protects us from possible danger by engaging a response within us in fight or fight situations. So it’s not the “bad guy”, you just have to learn how to control it. Panic attacks, however, are far more dangerous and should be a concern to your health. Panic can sometimes result in blurred (模糊不清的) vision, difficulty in breathing due to a tight chest. The best way to different anxiety from any serious illness is to ask a medical expert for advice on a regular basis.
小題1:According to the passage, a panic attack is _______________.
A.a(chǎn)s serious as an anxiety attackB.not so serious as an anxiety attack
C.resulted from an anxiety attackD.resulted in an anxiety attack
小題2: The underlined word “escalates” in the second paragraph means “_______________”.
A.happens suddenlyB.becomes more serious
C.mixes things togetherD.connects something with
小題3:A victim of anxiety attacks may have the symptoms that ______________.
A.he doesn’t want to have anything to eat
B.he has trouble in hearing and vision
C.he is always worried about others
D.he can’t pay attention to what he does
小題4:From the passage we can draw a conclusion that ______________.
A.a(chǎn)n anxiety attack does good to usB.a(chǎn)n anxiety attack does no harm to us
C.a(chǎn)n anxiety attack is a serious illnessD.a(chǎn)n anxiety attack is very dangerous
小題5: What is the best title for this passage?
A.Symptoms of Anxiety AttacksB.Ways of Getting Rid of Anxiety
C.Harm Caused by AnxietyD.Getting to know Anxiety

查看答案和解析>>

科目:高中英語(yǔ) 來(lái)源:不詳 題型:閱讀理解


C
Latest data shows an estimated 39.5 million people around the world are living with HIV, the virus that causes AIDS. According to the report, this means every eight seconds somebody in the world is infected with HIV, resulting in 11,000 people becoming newly infected every day.
The director of UNAIDS, Peter Piot, says most of the new infections, nearly two-thirds, are in Sub-Saharan Africa. But, the biggest increases are in Eastern Europe and Central Asia, where infection rates have risen by more than 50 percent since 2004. He says 2.9 million people died from AIDS-related illnesses this year, the highest number ever.
UNAIDS senior epidemiologist(流行病學(xué)家), Karen Stanecki, says infections are rising in countries where HIV prevention programs have not adapted to the changing nature of the epidemics(流行病).  Stanecki noted,"In Thailand, one of our past success stories, a large percentage of new HIV infections are occurring in people considered to be low risk. One third of new infections are among married women."
It says data shows increased use of condoms has resulted in drops in HIV prevalence(流行) among young people between 2000 and 2005 in a number of African countries, including Botswana, Kenya and Zimbabwe. Nevertheless, the report notes young people between the ages of 15 and 24 account for 40 percent of new HIV infections. It finds the risk behavior, such as injecting drug use, homosexuals, is a factor of concern in many regions of the world, especially in Asia, Eastern Europe and Latin America.
The report notes the emergence (出現(xiàn)) of injecting drug use as a factor of HIV in Kenya, Tanzania, Nigeria and South Africa is a recent development in Sub-Saharan Africa.
51. According to the news report, how many people are newly infected with HIV a year?
A. 39.5 million.            B. 2.9 million.             C. 3.5 million.              D. 4 million.
52.   The highest rate of new HIV infection is in ________.
A. Sub-Saharan Africa                                      B. Eastern Europe
C. Central Asia                                                 D. both A and B
53. The underlined word “noted” in the third paragraph mean?
A. specially mentioned                                     B. said angrily
C. fully noticed                                                D. uttered weakly
54.   Which of the following statements is Not True?
A. Most of new infections of HIV are among married women.
B. Two fifths of the new infections are among young people aged 15 to 24.
C. The risk behavior, such as injecting drug use and homosexuals, exists in many parts of the world.
D. Injecting drug use occurs in many African countries.
55.   What is the main idea of the new report?
A. More and more women in the world are getting new HIV infection.
B. The AIDS epidemic continues to grow in the world.
C. The AIDS epidemic has been reduced in the world.
D. No one can tell when the AIDS epidemic will be completely controlled.

查看答案和解析>>

科目:高中英語(yǔ) 來(lái)源:不詳 題型:閱讀理解

There are many commonly held beliefs about eyeglasses and eyesight that are not proved facts. For example, some people believe that wearing glasses too soon weaken the eyes. But there is nothing to show that the structure (結(jié)構(gòu)) of eyes is changed by wearing galsses at a young age. Wearing the wrong galsses, however, can prove harmful. Studies show that only children can develop loss of sihgt if they have the wrong glasses. We have all heard some of the common myths(荒誕的說(shuō)法)about how eyesight get bad. Too little light makes the eyes work harder, so they do get tired and strained (過(guò)勞). Eyestrain also resulsts from reading a lot, reading in bed, and watching too much television. But, although eyestrain may cause some pain or headaches, it does not harm eyesight all the time. Another myth about eyes is that they can be replaced from one person to another . It is quite difficult to connect aneyeball to a new brain.And it is impossible to replace a whole eyeball to a new person. Only certain parts of the eye can be replaced now. But if we keep clearing up the myths and learning more about the eyes, some day it may be possible to replace a full eyeball.
小題1:
One cause of eyestrain mentioned in the passage is ____.        .
A.wearing eyeglasses too long B.going to the cinemas
C.reading a lotD.not visiting your eye doctor
小題2:
.From this passage one can conclude that    ____.   .
A.doctors are still learning things about eyesightB.headcaches are usually caused by eyestain
C.people should wear glasses as soon as possibleD.people only believe things that are proved facts
小題3:
"Commonly held beliefs" are ____.       .
A.ideas that only low class people believeB.ideas that moet people believe
C.beliefs that have something in commonD.foolish beliefs
小題4:
This passage mainly tells us that ____.
A.people have many wrong beliefs about eyes and sight.
B.there are many things about the body that are not completely understood
C.there are several cuases of eyestrain
D.eyes are very important to people

查看答案和解析>>

科目:高中英語(yǔ) 來(lái)源:不詳 題型:閱讀理解

The gray-haired lady can’t wait to leave the building to search for her dad. Unless watched, she will walk in the streets in an effort to find her father, who died 30 years ago.
Not all cases of Alzheimer’s disease look like this, but Alzheimer’s is a serious disease that is said to be the fourth or fifth leading cause of death for people over age 75. It is said that about three percent of the U.S. population over age 65 have Alzheimer’s. In the early stages, people may exhibit short-term memory loss. Some may experience changes in personality, easy to be angry. As the disease progresses, patients might lose the ability to move and may be unable to speak or move at all. This progressive disease generally lasts 8 to 10 years before death occurs.
While no one is certain what causes these changes in the brain’s nerve fibers (神經(jīng)纖維), their effect is certain. Alzheimer’s destroys not only the patients, but also spouses(配偶), friends and families.
What should you do if you notice progressive memory loss in yourself or a loved one? Have the person examined by a doctor who is a specialist in the treatment of Alzheimer’s disease. Though many reasons other than Alzheimer’s disease may cause memory loss, its early diagnosis(診斷)and treatment may delay some of the most serious effects.
What feeling will you likely experience if a loved one suffers from Alzheimer’s disease? A person will often go through the various stages of sadness, shock, anger, and so on. If the spouse develops the disease, you may experience hurt and disappointment when he or she doesn’t remember you are married.
Life for the Alzheimer’s patients and their loved ones will never be the same as the disease progresses, bringing a deep sorrow, loss and even anger towards God. No matter what feelings are present, facing them honestly will serve one better than burying them.
小題1:What can be inferred from the passage about the gray-haired day?
A.She has been living with her father.
B.She was sad about the death of her father.
C.She can’t search for her father without being watched.
D.She suffers from Alzheimer’s disease.
小題2:When people suffer from Alzheimer’s disease, ________.
A.their families and friends will suffer from the same disease
B.their families and friends will experience mental sufferings
C.they will certainly die in 8 to 10 years
D.they will forget everybody but their spouses
小題3:Memory loss occurs ________.
A.from Alzheimer’s disease and nothing else
B.from sadness, shock, anger, and so on
C.for a number of reasons
D.with changes in personality
小題4:From the passage we know that        .
A.early treatment may stop Alzheimer’s disease occurring
B.it is still unknown what causes the changes in the brain’s nerve fibers
C.nerve fibers in the brain will cause Alzheimer’s disease
D.when one suffers from Alzheimer’s disease, he will be buried

查看答案和解析>>

科目:高中英語(yǔ) 來(lái)源:不詳 題型:閱讀理解

Ears are for hearing — everyone knows that. But for a creature called the Cuvier’s beaked whale, hearing starts in the throat (喉嚨), a new study found.
The observation might help explain how all whales hear. The work might also help scientists understand how animals are affected by underwater sonar (聲吶). This sonar, used by some ships, sends out sound waves to locate underwater objects.
The Cuvier’s beaked whale is a so-called toothed whale. Toothed whales dive deep into the ocean in search of food. As the whales hunt, they produce sounds that reach objects and then return to the whales. This allows the animals to “see” the shape, size, and location of objects, even when they’re 1,000 meters under the sea, where it is totally dark.
To better understand how the whale hears, researchers from San Diego State University in California took X rays of two Cuvier’s beaked whales. The whales had died and washed up on the beach.
Ted Cranford and his colleagues used the images to make a computer model of a Cuvier’s beaked whale’s head. Then, they modeled the process of sound traveling through the head.
The researchers knew that some sounds get to the ears of a toothed whale through a structure (構(gòu)造) called “the window for sound”. Found on the lower jaw, this structure is very thin on the outside and has a large pad (墊) of fat on the inside.
When the researchers used their computer model to work out how sound waves travel in the whale’s head, they were surprised to find that sounds coming from right in front of the whale actually travel under the animal’s jaw. From there, sound waves move through the throat, into a hole in the back of the jaw, and finally to the pad of fat near the animal’s ears.
69. 小題1:Toothed whales look for food under the sea by ______.
A.watching the shape and size of their objectsB.diving deep into the sea
C.sending and receiving soundsD.making lots of noises
70. 小題2:Researchers took X rays of two Cuvier’s beaked whales in order to ______.
A.find out why they had died and washed up on the beach
B.make a computer model of a Cuvier’s beaked whale’s head
C.make sure that sound travels through the head
D.know more about the way the whale hears
71. 小題3: Which of the following describes the way taken by sound waves through a Cuvier’s beaked whale?
A.A hole in the back of the jaw → the ears → the jaw → the throat.
B. The jaw → the throat → a hole in the back of the jaw → the ears.
C. The throat → the jaw → the ears → a hole in the back of the jaw.
D.The ears → the throat → a hole in the back of the jaw → the jaw.
72. 小題4:Which of the following is TRUE according to this passage?
A.The throat is important to the Cuvier’s beaked whale’s hearing.
B.Ships send out sound waves like a Cuvier’s beaked whale.
C.The ears are actually useless to the Cuvier’s beaked whale.
D.The researchers haven’t found how the whales hear.

查看答案和解析>>

科目:高中英語(yǔ) 來(lái)源:不詳 題型:閱讀理解


Our spiritual intelligence quotient (精神智商),or SQ, helps us understand ourselves, and live fuller, happier lives.
Though we're all born with SQ, most of us don’t even realize that we have it. Fortunately, you don't have to sign up for classes to learn how to improve your SQ. Here are some simple steps that can lead you to this new level of understanding.
Sit Quietly. The process of developing spiritual intelligence begins with solitude (獨(dú)處) and silence. To tune in to your spirit, you have to turn down the volume (強(qiáng)度) in your busy, noisy, complicated life and force yourself to do nothing at all. Start small by creating islands for silence in your day. In the car, instead of listening to the music, use the time to think. At work, shut the door to your office between meetings, take a few breaths and let them out very, very slowly. Enjoy the stillness in your home after the kids are finally in bed.
Step Outside.  For many people, nature sets their spirit free. Go outside to watch a beautiful sunset. If you are walking with the dog, take the time to admire flower in bloom; follow the light of a bird and watch clouds float overhead.
Ask Questions of Yourself. Ask open-ended questions, such as "What am I feeling? What are my choices? Where am I heading?"
But don't expect an answer to arrive through some supernatural form of e-mail. "Rarely do I get an immediate answer to my question," says Reverend Joan Carter, a Presbyterian minister in Sausalito, California. “But later that day I suddenly find myself thinking about a problem in a perspective(角度) I never considered before.”
Trust Your Spirit. While most of us rely on gut(本能的) feeling to realize danger, spiritual intelligence pushes us, not away from, but towards some action that will lead to a greater good.
68. The passage is mainly about           .
A. what your SQ is and in what way it can benefit our life
B. what your SQ is and in what way it can be improved
C. the relationship between your SQ and your life
D. advantages and disadvantages of SQ
69. The underlined phrase "tune in to your spirit" in the third paragraph probably means to _____.
A. get your spirit relaxed                   B. keep up your spirit
C. keep seated quietly                      D. change your spirit
70. The author mentions the example of Reverend Joan Carter to show that            .
A. there are no immediate answers to your questions
B. e-mails can't keep working out a problem
C. the more questions you ask, the better answers you'll get      
D. changing your way of thinking might help you solve a problem
71. From the passage, we can know that the most important thing to improve your SQ is      .
A. a peaceful mind    B. deep thought   C. spare time and hobbies   D. good spirits

查看答案和解析>>

科目:高中英語(yǔ) 來(lái)源:不詳 題型:閱讀理解


People today expect to be examined when they enter a doctor's office. At least they expect their blood pressure and temperature to be measured. However, as recently as two hundred years ago, a doctor's treatment depended on talking with patients. In general, the communication between doctors and their patients was the most important part of medical methods. The modem age of medicine began with the stethoscope ,an instrument for listening to patients heartbeat and breathing. Before that, a doctor did not touch a patient. In fact, there was no such things as a medical examination.
The stethoscope──and all other medical instruments──-had a serious effect, on the practice of medicine. Doctors became better at finding the medical problems. More lives were saved. At the same time, doctors gave less importance to the communication between patients and doctors. Some doctors actually stopped talking to their patients. It is easy to understand why some sick people thought themselves as broken machines.
1. A stethoscope can be used to________.
A. check health conditions     B. cure some illness
C. measure temperature       D. treat heart disease
2. Doctors gave less importance to the communication between patients and doctors mainly because________.
A. modern medical instruments were used
B. they could cure more diseases and save more lives
C. they had much more medical experience than before
D. they were too busy to have time to talk with patients
3. Some sick people thought of themselves as broken machines, which suggested that_______.
A. modern doctors should treat their patients as machines
B. the level of the treatment was greatly improved
C. they thought they were useless just like broken machines
D. they were not satisfied with the manner in which doctors treated them
4. The best title for this passage should be________.  
A. Medical Methods of Two Hundred Years Ago
B. The Development of Medical Methods
C. The Modem Age of Medicine
D. The Use of the Stethoscope

查看答案和解析>>

同步練習(xí)冊(cè)答案