Diabetes (糖尿病) and Eye Damage Over 2 million Canadians have diabetes. It is the leading cause of blindness in North Americans under 65 years of age. Diabetes is a condition where the body either cannot produce enough insulin (胰岛素) or cannot respond properly to insulin. Insulin is important because it moves glucose (葡萄糖), a simple sugar, into the body’s cells from the blood. The food people eat provides the body with glucose, which is used by the cells as a source of energy. If insulin isn’t available or doesn’t work correctly to move glucose from the blood into the cells, glucose will stay in the blood, leading to high blood sugar levels. High blood sugar levels damage the blood vessels, including the tiny blood vessels in the eye. This leads to an eye disease known as diabetic retinopathy (糖尿病型视网膜病). The retina (视网膜) is an area at the back of the eye that changes light into nerve signals. With diabetic retinopathy, some blood vessels in the retina are lost, and some of the other blood vessels begin to "leak" blood. This causes the retina to swell, and gradually cuts off its supply of oxygen and nutrients (滋养物). Eventually, the retina starts to grow new blood vessels to replace the damaged ones. Unfortunately, these new vessels are not as strong as the old ones. They are more likely to break, Causing bleeding in the eye. At first, people with diabetic retinopathy will not notice any symptoms. As the disease gets worse, they may notice blurred (模糊的) vision, black spots or flashing lights. As time goes on, it can progress to blindness. Everyone with diabetes is at risk for diabetic retinopathy, and the risk increases the longer you’ve had diabetes. Fortunately, you can reduce your risk. If you do not have diabetes, but think you may be at risk for this condition, visit your doctor to be screened for diabetes. If you do have diabetes: have frequent eye check-ups. Make sure that you monitor your blood sugar frequently and use your medications as recommended by your doctor. There is evidence to show that keeping your blood sugar under tight control can slow down eye damage. If you have high blood pressure, follow your recommended diet and medications to keep it under control. If you are not sure whether you have high blood pressure, or whether your blood pressure is under control, discuss this with your doctor. To slow down eye damage, people with diabetes should try to ______.
A. use as many medications as they can
B. eat as little as possible
C. wear glasses as often as possible
D. keep their blood sugar under tight control
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Ways to Reduce Exposure to Air Pollution 1. A report published recently brings bad news about air pollution. It suggests that it could be as damaging to our health as exposure to the radiation from the 1986 Ukraine nuclear power plant disaster. The report was published by the UK’s Royal Commission on Environmental Pollution. But what can city people do to reduce exposure to air pollution Quite a lot, it turns out. 2. Avoid walking in busy streets. Choose side streets and parks instead. Pollution levels can fall a considerable amount just by moving a few meters away from the main pollution source—exhaust fumes (废气). Also don’t walk behind smokers. Walk on the windward (顶风的) side of the street where exposure of pollutants (污染物) can be 50 percent less than on the downwind (顺风的) side. 3. Sitting on the driver’s side of a bus can increase your exposure by 10 percent, compared with sitting on the side nearest the pavement. Sitting upstairs on a double-decker (双层电车) can reduce exposure. It is difficult to say whether traveling on an underground train is better or worse than taking the bus. Air pollution on underground trains tends to be less toxic (有毒的) than that at street level, because underground pollution is mostly made up of tiny iron particles (粒子) thrown up by wheels hitting the rails, while diesel (柴油机) and petrol fumes have a mixture of pollutants. 4. When you are crossing a road, stand well back from the curb (路缘) while you wait for the light to change. Every meter really does count when you are close to traffic. As the traffic begins to move, fumes can be reduced in just a few seconds. So holding your breath for just a moment can make a difference, even though it might sound silly. 5. There are large sudden pollution increases during rush hours. Pollution levels fall during nighttime. The time of year also makes a big difference. Pollution levels tend to be at their lowest during spring and autumn when winds are freshest. Extreme cold or hot weather has a trapping effect and tends to cause a build-up of pollutants. Paragraph 5 ______
UFOs Sixty years ago, a man named Kenneth Arnold saw something that we can still 1 today something that changed popular culture for ever. Flying his plane over mountains in the US state of Washington, he saw a line of strange objects, either crescent-shaped (月牙形的) or disc-like, flying 2 the motion of a saucer (碟) skimming (飞速掠过) on water. The media soon picked up on the story—the Flying Saucers were here! Was the earth being 3 by creatures from another planet Soon, So many sightings were made that the US military began to 4 . It called these strange Objects UFOs—Unidentified Flying Objects, and that is how they are 5 today. Military investigations found no evidence of visitors from outer space. But that did not stop the true 6 . The military were 7 up, they said. Or maybe it was because the travelers from space were of such superior intelligence 8 they could hide from military analysts (分析家). People have always seen strange lights in the sky. In the past these were explained in 9 ways. In a world where religion was less influential and science fiction was popular, signs from God were replaced by visitors from other 10 . The date of the first UFO sightings was also significant. In 1947, World War Ⅱ had just ended and the 11 War was just beginning. Humanity seemed locked in endless conflicts. Like generations before them, people looked 12 the skies for help. But instead of seeking God, they looked for help from super-intelligent aliens (外星人) with 13 technology. Belief in UFOs became the first religion of science. However, even people who believe in UFOs are not quite sure why they visit the earth. The universe is a big place and it is 14 to assume that there is life somewhere out there. It is possible that aliens have worked out how to travel through space. Yet some people report that they have been taken by aliens and have had experiments 15 on them. Why would anyone travel across half the universe to conduct medical experiments on people living in small towns in the United States
A. cool
B. nuclear
C. Star
D. Cold
关于口腔颌面部感染,下列说法正确的是
A. 上呼吸道感染,可造成区域性淋巴结炎
B. 成人较儿童更易发生腺源性感染
C. 口腔颌面部感染可借血液循环扩散至邻近间隙
D. 危险三角区的感染处理不当可造成上呼吸道梗塞
E. 口腔颌面部组织抗感染能力较其他组织为低
Wayne Beno Wayne Beno was a true outdoorsman. Fishing, boating, hunting, walking through the woods with his three dogs, Wayne loved and did it all. Then life changed dramatically. Wayne was diagnosed with Parkinson’s disease (帕金森氏病). "For the next thirteen years I took 28 pills a day, had horrible side effects, and even with all those pills I still had lots of shaking and tremors (颤抖). I only went out during peak times, when I was looking and feeling my best. But that wasn’t often and I really couldn’t do much of anything. I felt like the life I loved was over," said Wayne. Then Wayne’s doctor in Green Bay suggested he consider a breakthrough surgical option being offered at Froedtert & the Medical College of Wisconsin called Deep Brain Stimulation (刺激) (DBS). DBS is a surgical option used to treat disabling movement disorders related to Parkinson’s disease, essential tremor and more. It is not a cure, but significant improvement is seen in most movement disorder cases, with relatively low risk to the patient. In addition to his doctor’s recommendation, Wayne had a neighbor and fishing friend who had the DBS procedure at Froedtert & the Medical College of Wisconsin. His friend’s experience convinced Wayne that the 180-mile trip from his home in Crivitz, Wisconsin could be well worth the effort. And was it ever. "It was the best thing I ever did. I’m down to zero pills a day and I don’t shake at all," reports Wayne. "Before the surgery, I felt bad every single day. Now I feel like my old self. I’m back to business as usual, which for me means fishing, fishing, and more fishing, every day of the year. Things just couldn’t be any better!" After the surgery, Wayne felt ______.
A. completely recovered
B. bad every single day
C. pain every now and then
D. worse than before the surgery