英语听力—环球英语 1228 Dogs: Saving Human Lives（打印版）

　　And I’m Robin Basselin. Spotlight uses a special English method of broadcasting. It is easier for people to understand, no matter where in the world they live.

　　Carol Witcher has a dog named Floyd Henry. She rescued him when he was 7 months old. She gave him a home and a good life. Floyd Henry was always a good dog. He behaved well. And he loved Carol.

　　In 2008, Floyd Henry began to act very strange. He began to smell Carol’s breath. He also began pushing against her breast. Sometimes, his pushes were very hard. Floyd Henry had never acted like this before.

　　Floyd Henry’s behaviour made Carol think that something was wrong with her. So, she went to the doctor. Medical tests showed that Carol had a life threatening disease – stage three breast cancer. Carol began radiation treatment and had an operation to remove the cancer. Now, Carol has been cancer free for three years. Her doctor, Sheryl Gabram-Mendola told the ABC news organization,

　　But how could this be? Did Floyd Henry really know Carol had cancer? Experts say it is possible. Today’s Spotlight is on how dogs can discover cancer and help save human lives!

　　Dogs have been part of human society since the earliest recorded times. Humans first welcomed dogs into their communities for safety. Dogs protected early humans from attacks by wild animals. Later, humans began to welcome dogs into their homes. Some people even consider their dog to be part of the family. Dogs have guarded and protected humans for years. Now, science is finding that they can even protect humans by discovering cancer.

　　Cancer is the number one cause of death around the world. It affects people in every country, culture and ethnic group. In 2008, almost 8 million people died from cancer. The World Health Organization estimates that these numbers will continue to increase. However, one way to decrease this numbers is to identify and treat cancer early. And it seems that dogs can help us do that.

　　But how do dogs know when someone has cancer? Many dog owners have reported stories similar to Carol’s story. Reports like these were very interesting to scientists. So, in the 1980’s, doctors began researching this question.

　　Scientists first found evidence that dogs could identify cancer in 1989. And they found that dogs could identify cancer by smell! They learned that the breath of cancer patients smells different than the breath of a healthy person. This is because cancer causes the body to release chemicals into the breath. Humans cannot smell these chemicals. But dogs can!

　　Dogs have a very strong sense of smell. The average dog has over 200 million smell receiving cells in its nose. This is over 50 times more than what a human nose has. These extra cells help dogs smell things that people cannot. One of those things appears to be cancer.

　　Many different kinds of dogs have the cancer smelling skill. Researchers have worked with dogs that are known for their smelling ability - like Labradors, Poodles, and Portuguese Water Dogs. People first trained these kinds of dogs to smell for bombs and guide blind people. But other scientists have had equal success using normal dogs as well.

　　Dr. Gary Beauchamp is the director of Monell Chemical Senses in Philadelphia in the United States. He told National Public Radio,

　　“A dog’s sense of smell is an almost miracle sense. It can smell very, very low levels of compounds.”

　　Charlene Bayer is an expert from George Tech Research Institute in the United States. She explained to the ABC news organization,

　　“Dogs may not know what is wrong. But they know that there is something that is not normal. They know that a person does not smell the way they normally do.”

　　So, dogs may not know that what they smell is the result of cancer. But, that does not make them less effective. They can identify many different kinds of cancer. In August 2011, scientists in Germany found that dogs can detect early stage lung cancer. The dogs correctly identified cancer 93% of the time. This means that dogs can find lung cancer better than any doctor or test there is today. This is important news because lung cancer kills more people in the world than any other kind of cancer.

　　Several other studies have confirmed a dog’s ability to find other kinds of cancer. Scientists in Japan even trained a dog to recognize bowel cancer. The dog smelled both the breath and human waste of 300 people. He correctly found cancer 98% of the time.

　　Today, doctors continue to research the ability of dogs to identify even more kinds of cancer. Currently, in the United States, doctors are studying the use of dogs to discover ovarian cancer. The United States’ National Cancer Institute reports that over 15,000 women die each year from ovarian cancer - in the United States alone. Doctors hope to find similar results in their ovarian cancer study as doctors have found with other cancers.

　　The ability of dogs to find cancer is exciting. But it would be difficult to have a dog in every doctor’s office. So, a company in California in the United States is working to build a cancer smelling device. This device is like an electronic nose. They hope it can copy a dog’s amazing skill to smell cancer.

　　To make the electronic nose, the company is using the years of research on dogs and cancer. And the electronic nose has advantages over traditional cancer tests. For example, the machine is low cost to use. It also does not require the patient to have an operation. All the patient needs to do is breathe into a machine! Then, the machine “smells” for chemicals in the breath. The first machine correctly identified cancer 80% of the time. This is not as effective as a dog’s nose. But, the company is working on a second model to improve the results.

　　Scientists still have much work to do. They need to learn more about exactly what chemicals dogs smell in a cancer patient’s breath. And the more doctors discover about a dog’s nose, the more they can use the information to save cancer patient’s lives.

　　People like Carol Witcher are already experiencing the life saving effects of dogs’ cancer smelling skills. And she is very thankful for her dog, Floyd Henry. She told ABC News,

　　The writer of this program was Ann Wilds. The producer was Mark Drenth. The voices you heard were from the United States. All quotes were adapted and voiced by Spotlight. You can find this program on the internet at www.radioenglish.net. This program is called, “Dogs: Saving Human Lives.”

英语听力—环球英语 1228 Dogs: Saving Human Lives（在线收听）