2017年雅思阅读理解考试专项训练试题带答案.docVIP

2017年雅思阅读理解考试专项训练试题带答案 学而时习之，不亦说乎?以下是小编为大家有哪些信誉好的足球投注网站整理2017年雅思阅读理解考试专项训练试题带答案，希望能给大家带来帮助!更多精彩内容请及时关注我们应届毕业生! 　　Why did a promising heart drug fail? 　　Doomed drug highlights complications of meddling with cholesterol. 　　1. The failure of a high-profile cholesterol drug has thrown a spotlight on the complicated machinery that regulates cholesterol levels. But many researchers remain confident that drugs to boost levels of #39;good#39; cholesterol are still one of the most promising means to combat spiralling heart disease. 　　2. Drug company Pfizer announced on 2 December that it was cancelling all clinical trials of torcetrapib, a drug designed to raise heart-protective high-density lipoproteins (HDLs). In a trial of 15000 patients, a safety board found that more people died or suffered cardiovascular problems after taking the drug plus a cholesterol-lowering statin than those in a control group who took the statin alone. 　　3. The news came as a kick in the teeth to many cardiologists because earlier tests in animals and people suggested it would lower rates of cardiovascular disease. There have been no red flags to my knowledge, says John Chapman, a specialist in lipoproteins and atherosclerosis at the National Institute for Health and Medical Research (INSERM) in Paris who has also studied torcetrapib. This cancellation came as a complete shock. 　　4. Torcetrapib is one of the most advanced of a new breed of drugs designed to raise levels of HDLs, which ferry cholesterol out of artery-clogging plaques to the liver for removal from the body. Specifically, torcetrapib blocks a protein called cholesterol ester transfer protein (CETP), which normally transfers the cholesterol from high-density lipoproteins to low density, plaque-promoting ones. Statins, in contrast, mainly work by lowering the #39;bad#39; low-density lipoproteins. 　　Under pressure 　　5. Researchers are now trying to work out why and how the drug backfired, something that will not become clear until the clinical de