【题记】这是一篇我做内部培训工作时无意中搜集到的文章，原文出处在http://news.yahoo.com/did-lance-armstrong-avoid-positive-doping-test-182038095.html，由于原文作者应该是分析检测行业的内部人士，因此讲解到位，读来极其生动有趣，正好可以用来解答我的服务对象对于分析检测工作认识的误区。为了便于阅读，采取英中对照（未必逐词翻译）的方式，力求将主要内容翻译到位。此文尚未见到完整译文，因此我保留对中文译文的版权诉求。
The evidence presented in the U.S. Anti-Doping Agency's 202-page report on Lance Armstrong's alleged years of doping, scheming, pushing and evading is, according to its authors, "beyond strong." Even so, the case against Armstrong doesn't involve any definitive failed drug tests, a fact that the former seven-time Tour de France winner has long used to shield his claims to innocence.
在美国反兴奋剂机构宣称阿姆斯特朗常年使用兴奋剂的长达202页的报告中，报告作者认为其中所罗列的证据是“超有力”的。即便如此，阿姆斯特朗一案中并没有包括那些失败的药检结果，这些曾使得这位前七次环法赛冠军长期保有无辜的名声。
So if Armstrong is the inveterate doper the USADA claims he is, how did he manage to avoid an unambiguous positive test during more than a decade of pro cycling?
那么，如果阿姆斯特朗是如USADA（美国反兴奋剂机构，下用英文缩写）所说的资深服药者，他是如何在从事超过十年职业自行车运动过程中做到避免出现本应明白无误的阳性检测结果的呢？（有些小拗口）
Below is a rundown of the doping practices the USADA accuses Armstrong of using, and an explanation of how, in each case, he might have covered his tracks for so long.
以下是USADA所罗列的阿姆斯特朗所用手段的简表，针对每种情况，他隐藏了他服药的痕迹。
Erythropoietin (EPO): A synthetic version of this naturally occurring hormone is used by cheating athletes to boost red blood cell counts, a change that temporarily supercharges endurance by increasing muscles' oxygen-carrying capacity. Before 2000, no test existed to distinguish the synthetic version of the hormone from its natural counterpart, so as long as athletes took doses that would keep their hematocrit (a measure of the volume percentage of blood made up of red blood cells) in a plausible range (below 50 percent), they could use this drug with impunity. And the report alleges that Armstrong's pre-2000 team did just that, fueling its 1999 Tour de France win.
红细胞生长素（EPO）：EPO是一种合成的荷尔蒙，可以促进提高红血球数量，暂时性的提高肌肉的携氧量。在2000年前，没有检测方法可以区分EPO（合成版）和其对应的自然版。（这句话的意思就是分不清山寨版和原版）于是运动员可以放心大胆的用药。报告指控阿姆斯特朗在2000年前这么干过，1999年夺取了环法冠军。
But the USADA also claims that Armstrong's abuse of EPO didn't stop after the introduction of a urine test capable of detecting the drug in 2000; it merely took a more covert form. Conspiring doctors, the report alleges, instructed Armstrong and his teammates to inject EPO intravenously (as opposed to subcutaneously, or into an inner layer of skin) and at night, when surprise tests were unlikely. These measures would make it possible for low doses of synthetic EPO to be cleared from a rider's system by the time he woke.
但是USADA指出阿姆斯特朗在引入尿检检测EPO（2000年）后，依然继续滥用EPO。同谋的医生（要注意这个高人，下面应该还有他的杰作），给阿姆斯特朗和他的队友支了一招：在晚上（此时通常不会有突然抽检）静脉注射EPO。这样一觉醒来，低剂量的EPO就会消失无踪（我估计是代谢掉了）。
In situations where EPO tests on recently dosed athletes were unavoidable, team doctors also could have injected saline, or salt water, to dilute a rider's blood and quickly drive down hematocrit. This kind of obfuscating saline injection was a common practice for Armstrong and his team, according to the USADA report.
但是如果EPO检测时间距离运动员注射EPO的时间距离太短时（时间不够用），车队的医生们会注射生理盐水或盐水，这样能稀释骑手的血液，降低血细胞比容。根据USADA的描述，这法儿阿姆斯特朗和他的车队常用！
Blood Transfusions: Strategic blood transfusions, in which an athlete re-injects stored backup units of blood for a red blood cell boost, achieve the same effects as synthetic EPO use while avoiding that drug's signature test markers. Since the process involves just an athlete's own blood, it is notoriously hard to detect; but looking for anomalous hematocrit levels was a tester's best shot at finding transfusers when Armstrong was riding. Therefore, pre-test injections of saline would have been just as effective in thwarting detection as for EPO use. The USADA alleges Armstrong and his teammates also used EPO as part of their transfusion cover-ups, stimulating the production of immature red blood cells with small doses of the synthetic drug to balance out elevations in mature red blood cells that are a telltale sign of a transfusion.
输血：策略性的输血，给运动员输事先准备好的储备血可以达到与EPO相类的效果，但是又可以避免留下相应的痕迹。这种方式极难检测（很好理解，基体基本完全一致，后面的描述很多，大意就是阿姆斯特朗的团队采用了输血、输血+摄入EPO、打盐水等组合拳来使得检测结果为阴性）。
Testosterone: Used by athletes to improve muscle mass, muscle recovery and endurance, testosterone occurs naturally in the body.Baseline levels of the hormone vary widely among different people, and one person's levels can vary widely from day to day. So positive tests for synthetic testosterone are based on a weight of evidence, not any surefire marker, and considerable leeway has to be given to ensure that no innocent athletes are punished for natural variations. (Athletes in the 2012 Olympics were allowed four times the normal levels of testosterone before they tripped a drug test.) This testing strategy, though logical, is highly vulnerable to passing over athletes who abuse testosterone in small doses, enough to give them an edge but not a positive test. The USADA alleges Armstrong and his team used just such a low-dose testosterone regimen. The report also claims that a doctor associated with Armstrong created a unique method of testosterone delivery, via an olive oil formulation that riders dribbled under their tongues, specifically designed to narrow the window of detection. [How Steroids Work]
男性荷尔蒙（睾酮）：运动员用来提高肌肉质量、肌肉恢复能力和持久性，睾酮可以在体内自然产生（这个不用解释了吧？）由于个体差异，睾酮在每个人体内的含量都不一样，所以很难判断运动员是否服用了人工合成的睾酮，在2012年奥运会的药检中，允许高于平常值的四倍。
Human Growth Hormone (HGH): Another naturally occurring hormone, HGH is used by athletes to promote muscle growth and recovery. According to Larry Bowers, the science director of the USADA, there were no available tests for HGH at the time of Armstrong's first retirement in 2005, so if Armstrong and his teammates consistently used them before that year, as the USADA claims, they could have avoided detection.
Corticosteroids: These chemicals, also natural hormones with synthetic analogues, can be used by athletes to ease inflammation and promote muscle recovery. Armstrong tested positive for a corticosteroid, cortisone, in 1999, the year of his first Tour de France win. The USADA says a team doctor then fabricated and backdated a prescription for the cortisone to excuse the positive result, claiming that Armstrong had been using cortisone to treat a "saddle sore." Because cortisone is only outlawed among cyclists who don't have a medical need for it, dishonest doctors can easily give cheaters cover under a phony prescription.
Saline and plasma transfusions: Injections of plasma (a pale, yellow liquid that makes up a large part of blood) and saline are outlawed because of their usefulness in masking blood transfusions and EPO violations. Armstrong's doctors are alleged to have closely monitored his hematocrit levels to stay a step ahead of testing. Jonathan Vaughters, a former Armstrong teammate, alleges that a team doctor once smuggled a bag of saline directly past an International Cycling Union tester, inside his raincoat, and delivered it to Armstrong just in time to thwart an EPO test.
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