VOA慢速英语:Rethinking 'Good' Cholesterol; PSA Test Debate

A study has raised questions about a widely held belief involving cholesterol. The belief is that high levels of so-called good cholesterol in the blood can reduce the risk of a heart attack.
一项研究对一种涉及胆固醇的广泛观点提出了质疑。这种观点是血液中高浓度的所谓的有益胆固醇能够降低心脏病发作的风险。

The medical name for "good" cholesterol is high-density lipoprotein, or HDL. Doctors commonly believe it reduces the risk of heart attack by removing fatty deposits that can block the flow of blood in the arteries of the heart.
医学名为高密度脂蛋白是益的胆固醇。医生们普遍认为它能通过移除阻碍心脏动脉血液流动的脂肪沉积，降低心脏病发作的风险。

But Dr. Sekar Kathiresan at Massachusetts General Hospital in Boston says the effects of high HDL have never been proven. He says the new study that he and other researchers did suggests that HDL cholesterol does not affect the risk of heart attack.
但波士顿市马萨诸塞总医院的Sekar Kathiresan医生称，高密度脂蛋白的影响从来就没有被证明。他说，他和其他研究人员做的这项新研究表明，高密度脂蛋白胆固醇不影响心脏病发作风险。

SEKAR KATHIRESAN: "This has been the major assumption over the last thirty years, that if you raise HDL cholesterol, the risk for heart disease will be lowered. And I think we have now broken that assumption, broken that link using this gene variant."
SEKAR KATHIRESAN：“这是过去30年的一种主要假设，如果你提高高密度脂蛋白胆固醇，患心脏病的风险将会降低。而我认为，采用基因变异，我们现在已经打破了这种假设，打破了这种联系。”

The researchers say about four percent of people have a genetic change that gives them a naturally high level of HDL. The study found that those who were genetically "programmed" to have higher HDL levels were just as likely to suffer heart attacks as those who were not.
研究人员称，约4%的人有一种遗传性的变异，使得他们天生就有高水平的高密度脂蛋白。研究发现，这种天生拥有更高水平的高密度脂蛋白的人与普通人一样会患心脏病。

A second analysis looked at fourteen gene variants that increase good cholesterol. Dr. Kathiresan says people with the most variants had no more protection against heart attacks than anyone else.
第二项分析研究了能够提升有益胆固醇含量的14个基因变异。Kathiresan医生表示，拥有大多数基因变异的人群与其他人相比，并没有更好地防止心脏病的发作。

But he says there is no dispute about low-density lipoprotein, or LDL. LDL, the so-called bad cholesterol, causes a buildup of fatty substances inside arteries and increases the risk of heart attack.
但他说，对于低密度脂蛋白，也就是所谓的有害胆固醇，会导致动脉内的脂肪物质积聚，增加心脏病发作的风险是没有争议的。

Dr. Kathiresan and his colleagues published their findings in the Lancet medical journal.
Kathiresan医生及其同事将他们的研究结果发表在《柳叶刀》医学杂志上。

Another widely held medical belief has also come into question recently. For years, men over the age of forty have been told to get a simple blood test to see if they have prostate cancer. Now, experts on a government committee are advising them not to. Dr. Virginia Moyer heads the United States Preventive Services Task Force
另一种广泛医学观点最近也引发了质疑。多年来，40岁以上男子被告知进行一种简单的血液测试，看他们是否患有前列腺癌。现在，一个政府委员会的专家建议他们别样做。Virginia Moyer医生领导美国预防服务工作队。

VIRGINIA MOYER: "Close to two-thirds of older men have prostate cancer and yet the huge majority of them never have a problem from it in their lifetime."
VIRGINIA MOYER：“接近三分之二的老年男性有前列腺癌。但他们中的绝大多数一生中都未因为这个产生什么问题。”

The task force examined two large studies before deciding that treating the cancer found by the PSA test can do more harm than good. Effects of the treatment can include a loss of sexual ability and bladder control, as well as other problems including heart attacks.
专案组审查了两个大型研究，才断定对PSA测试发现的前列腺癌的治疗弊大于利。这种治疗的后果包括丧失性能力和膀胱控制，以及心脏病发作等其它问题。

Some doctors support the findings of the task force, but others disagree. Urologist Deepak Kapoor says in about twenty years of PSA testing, death rates for prostate cancer have dropped by thirty-eight percent.
有些医生支持专案组的调查结果，但其他人并不同意。泌尿科医生Deepak Kapoor称，在20多年的PSA测试中，前列腺癌的死亡率下降了38%。