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「普特聽力短文」原來靜脈血管是這樣的

　　普特英語聽力是現在比較受學生歡迎的英語聽力材料之一，經常聽普特英語聽力確實對學生提高英語聽力有很好的好處。下面，小編就為大家送上一篇普特聽力短文，希望對大家有用。

　　普特聽力短文：

　　Veins are pretty important. After all, they carry blood from various parts of the body to the heart. But for all their significance, veins are modest, too. Yours are probably content to work behind the scenes, tucked away beneath the skin.

　　Twisted And Filled

　　Sometimes, however, veins take center-stage and become visible as blue lines on the skin, often resembling an unmarked roadmap. If you haven’t guessed by now, we’re talking about varicose veins. Have you ever wondered what are they are and how they form?

　　Basically, a varicose vein is one that is twisted and filled with backed-up blood. Although they most commonly occur in the legs, varicose veins can also happen in the esophagus, testes and the urinary bladder.

　　Varicose veins in the legs occur when the valves in a vein near the surface of the skin malfunction.

　　Faulty Valves

　　Valves usually keep blood from flowing backwards in the vein once it’s been pumped towards the heart. When the valves don’t work properly, blood gets stuck, causing the vein to swell and kink.

　　Although varicose veins are usually associated with senior citizens, not every older person has them. Weak valves are often inherited, and can also be caused by wearing clothing that squeezes the legs and veins too tightly.

　　Varicose veins may seem unsightly, but they’re not usually a cause for major concern. Still, if you have them and want to do something about it, talk to your doctor. Treatments range from wearing strong support stockings to surgery.

　　參考譯文：

　　血管相當的重要。畢竟，它們從身體的各個部分向心臟運輸血液。雖然血管很重要，但是它們也很謙遜。血管甘愿在幕后工作，在皮膚下默默運輸血液。

　　扭曲的并充滿的

　　然而，有時候血管成為主角，在皮膚上可以看到藍色的線，很像未被標記的地圖。如果你還沒有猜到，我們討論的正是靜脈曲張的血管。你是否想知道它們是什么并怎樣形成的么?

　　通常，靜脈曲張的血管充滿回流的血液并因此扭曲。它們不僅多見于腿部，也會表現在食管、睪丸、膀胱上。

　　當皮膚表面下的血管的閥門不起作用時，腿上的靜脈曲張開始顯現。

　　受損的瓣膜

　　閥門的作用是防止有心臟送出的血液回流。當閥門不正常工作時，血液不能流動，導致血管膨脹和扭結。

　　雖然靜脈曲張多發(fā)生在老年人身上，但是不是每個老年人都患有這種病。脆弱的閥門通常是遺傳的，或者身上的衣服把腿和血管勒的太緊導致的。

　　靜脈曲張是很難看的，但是它們通常不會引起強烈的關注。然而，如果你有這種病并想要治療，和你的醫(yī)生聊聊。治療方法包括從穿修復性的長筒襪到做外科手術。

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