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运用记忆规律，谈谈如何促进知识的保持。
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Cheating in sport is as old as sport itself. The athletes of ancient Greece used potions to fortify themselves before a contest, and their modern counterparts have everything from anabolic steroids and growth hormones to doses of extra red blood cells with which to invigorate their bodies. These days, however, such stimulants are frowned on, and those athletes must therefore run the gauntlet of organizations such as the World Anti-Doping Agency (WADA), which would rather that athletes competed without resorting to them. The agencies have had remarkable success. Testing for anabolic steroids (in other words, artificial testosterone) was introduced in the 1970s, and the incidence of cheating seems to have fallen dramatically as a result. The tests, however, are not foolproof. And a study just published in the Journal of Clinical Endocrinology & Metabolism by Jenny Jakobsson Schulze and her colleagues at the Karolinska Institute in Sweden suggests that an individual’s genetic make-up could confound them in two different ways. One genotype, to use the jargon, may allow athletes who use anabolic steroids to escape detection altogether. Another may actually be convicting the innocent. The test usually employed for testosterone abuse relies on measuring the ratio of two chemicals found in the urine: testosterone glucuronide (TG) and epitestosterone glucuronide (EG). The former is produced when testosterone is broken down, while the latter is unrelated to testosterone metabolism, and can thus serve as a reference point for the test. Any ratio above four of the former to one Of the latter is, according to official Olympic policy, considered suspicious and leads to more tests. However, the production of TG is controlled by an enzyme that is, in turn, encoded by a gene called UGT2B17. This gene comes in two varieties, one of which has a part missing and therefore does not work properly. A person may thus have none, one or two working copies of UGT2B17, since he inherits one copy from each parent. Dr. Schulze guessed that different numbers of working copies would produce different test results. She therefore gave healthy male volunteers whose genes had been examined a single 360rag shot of testosterone (the standard dose for legitimate medical use) and checked their urine to see whether the shot could be detected. The result was remarkable. Nearly half of the men who carried no functional copies of UGT2B17 would have gone undetected in the standard doping test. By contrast, 14% of those with two functional copies of the gene were over the detection threshold before they had even received an injection. The researchers estimate this would give a false-positive testing rate of 9% in a random population of young men. Dr. Schulze also says there is substantial ethnic variation in UGT2B17 genotypes. Two-thirds of Asians have no functional copies of the gene (which means they have a naturally low ratio of TG to EG), compared with under a tenth of Cancasians—something the anti-doping bodies may wish to take into account. In the meantime, Dr. Schulze’s study does seem to offer innocents a way of defending themselves. Athletes traveling to Beijing for the Olympic games may be wise to travel armed not only with courage and the "spirit of Olympianism", but also with a copy of their genetic profile, just in case. According to official Olympic policy, which of the following ratio between TG and EG is considered suspicious
女性，68岁，突发晕厥1次，持续10分钟，醒后感前胸持续闷痛，有糖尿病史2年，高血压病史2年。查体：血压80/60mmHg，心率50次/分，双肺闻及湿哕音，心音低钝，心电图示Ⅱ、Ⅲ、aVF、V7～9、V3R～5R导联ST段抬高＞0.1mV。 [假设信息]上述患者心尖部出现收缩期吹风样杂音，应立即进行的检查为
王磊系国内某国营企业职工，2005年5月，王磊被派到某外资企业工作，当月取得的收人情况如下：（1）外资企业本月支付给王磊的工资为4000元；原单位支付的工资额为1000元；（2）王磊2004年曾与人合著过一本书，本月分得稿酬收入8000元；（3）2005年1月，王磊住所被盗，损失6000元，本月收到保险公司赔款3000元；（4）在行业主管部门举办的技术竞赛中，获得“先进技术个人”奖，本月取得奖金2000元；（5）本月1日，将2000年2月从原单位按成本价5万元购买的房屋转让出去，本月取得转让收入50万元。甲的住房面积标准为80平方米，原实际住房面积为85平方米，当地经济适用房房价为每平方米900元，超标部分王磊以每平方米1200元的价格购买。按照甲与原单位签订的相关协议，甲出售住房所得价款的20%应上缴原单位；（6）本月20日，按市场价格购入新的普通住宅一套，价值70万元；（7）2003年购买的国库券到期，取得利息收入2200元；（8）本月在外资企业取得季度奖3000元；（9）本月为另一企业提供设备装配服务，取得不含税劳务报酬2000元。要求：指出王磊本月取得的各项收入的个人所得税的具体计算方法及过程，计算王磊本月合计缴纳的个人所得税及本月应缴的契税（当地规定的契税税率为5%）。
根据记忆依存时间的长短，可以把记忆分为______、______和长时记忆三种类型。
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