Dogs might have the latest tools in the fight against cancer (癌症); their noses! Researchers at California'sPine Street Foundation(PSF) say they have trained five dogs to smell cancer on a prison's breath. This could be exciting news.
A dog's sense of smell may be 10,000 to 100,000 times stronger than ours. But can dogs really smell illness?PSFresearcher Michael McCulloch says yes. "We were very surprised by how exact they were," he said. "They were telling who had cancer, and they were also saying who didn't."
| Dogs in the Pine Street Foundation test were trained to sit when they smelled cancer. How well did they perform? Take a look at this chart to find out. | ||
| Breath Sample | Number of Times the Dogs Sat Down | Number of Times the Dogs Kept Standing |
| Breath from lung cancer patients | 564 | 10 |
| Breath from healthy persons | 4 | 708 |
McCulloch and his team asked four healthy people and one with cancer to blow into plastic tubes (塑料管). Special materials in the tubes kept the things of each breath. The tubes were then placed one yard apart. Finally the dogs were allowed to smell the tubes. Each dog had been trained for three weeks to sit when it smelled cancer. Ninety-nine percent of the time, the dug sat next to the tubes blown into by patients with lung cancer. The dogs were right 88 percent of the time about breast cancer.
No lab test for cancer has given more correct results than this test. The results are so amazing that many experts question the dogs' smelling power. They wonder if there were other reasons why the dogs did so well. For example, they thought the way the dog trainers behaved could have influenced how the dogs acted. However, most experts agree that this study is important. The information could help scientists create a simple breath test for cancer in the future. Once again humans may be getting a helping paw or nose—from their best animal friends.
