第十二篇 The Enemy Within
Allergy has become more and more common over the last 30 years. Now one-third of us are affected by allergy at some point in our lives and half of these sufferers are children. In the UK, three million people suffer from asthma, and five per cent of children suffer from food allergy.
Allergy is a reaction that occurs when the immune system has a strange and unnecessary reaction to a substance which is normally harmless, such as pollen or peanuts. ____1____ To defend your body against an attacker, the immune system remembers these dangerous micro-organisms and attacks them if it meets them again. This work is done by antibodies. The immune system in allergy sufferers makes antibodies against harmless substances, because it mistakenly believes them to be dangerous.
An allergic reaction may not happen the first time a sufferer meets an allergen (the substance causing the reaction, such as pollen, milk or strawberries). Sometimes people can eat nuts for years and then suddenly become allergic to them. What has happened is that the immune system has now decided the substance is dangerous and has made an allergy antibody. This antibody then attaches itself to cells, which contain histamine. ____2____ As they do that, the surface of the cells is broken, and histamine is released. The histamine and other chemicals inflame the tissues. This leads to the symptoms of allergy, such as swelling, rashes, sneezing, sore eyes and breathlessness. Anaphylaxis is the most severe allergic reaction of all and is most often triggered by wasp or bee stings or peanuts. This must be treated immediately.
____3____ Some people are born with the ability to make lots of allergy antibodies, and they are more likely to develop allergies and allergic disorders such as hay fever and asthma.
____4____ We eat more processed foods, with a wide range of additives and colourings; more and more people have central heating and double glazing, making our houses warmer and less draughty-an ideal environment to breed the house dust mite.
There may also be a link between allergies and antibiotics. At one time our immune systems were kept busy fighting off disease and trying to win the battle for health, but antibiotics have reduced the amount of work our immune systems have to do. Now experts think they may direct spare energy to harmless substances such as strawberries. ____5____
A good deal of research is being devoted to finding a cure for allergies. Sufferers may be given medicine to control symptoms, and they may also be offered tests to find out what substances trigger an allergic reaction so that they can avoid contact with these in future.
詞匯：
allergy n. 過敏，過敏癥
sufferer n. 患者，受害者
asthma n. 哮喘
substance n. 物質(zhì)
pollen n. 花粉
micro-organism n. 微生物
antibodies n. antibody的復(fù)數(shù)形式，意為抗體
allergen n. 過敏源
nut n. 堅果
histamine n. 組織胺，組胺
tissue n. 人體組織
symptom n. 病癥，征兆
rash n. 皰疹
sneezing n. 打噴嚏
breathlessness n. 呼吸急促，氣喘吁吁
anaphylaxis n. 全身性過敏反應(yīng)，過敏反應(yīng)
wasp n. 黃蜂
sting n. 蟄，咬
hayfever n. 枯草熱，花粉病
additives n. 添加劑，食品添加劑
cure n. 治療，解藥
注釋：
1.suffer from...忍受^的折磨
2.be devoted to sth. ...全身心投入于^
練習(xí)：
A The immune system is there to protect the body against outside attackers, including viruses, bacteria and parasites.
B In other words our immune systems have become over-sensitive.
C Allergies run in families.
D International differences have been associated with the number of individuals within a population have allergy.
E When the antibodies meet the allergen the next time, they attempt to destroy it.
F Experts believe more people have developed allergies because of changes in our lifestyle which have exposed us to more allergens.
答案與題解：
1.A 該是對機體免疫系統(tǒng)功能的介紹，而文中對免疫系統(tǒng)的首次提及是在該選項的上一句話，即描述過敏反應(yīng)是免疫系統(tǒng)的活動，該選項故而可被視為是對上一句話的補充與說明。
2.E 本題做題線索有兩點，首先是上下文，本段前幾句都是對抗體的描述與介紹，故與選項E主題相符，同時第二個做題點為邏輯順序詞，本段的第一句話中提到了An allergic reaction may not happen the first time a sufferer meets an allergen，而該選項中又有了the next time，這兩個邏輯順序詞也構(gòu)成了解題線索。
3.C 該選項在文章的第四段，講的是過敏反應(yīng)在特殊人群中的反應(yīng)，選項C的意思為“過敏反應(yīng)是具有遺傳性的”，與該段后一句some people are born with the ability...相對應(yīng)。
4.F 文章第五段主要講的是能導(dǎo)致過敏反應(yīng)的兩個例子，缺少中心句，而選項C恰好能對這兩個例子進行概括說明，故答案為選項C。
5.B 該選項為概括總結(jié)項，是對前文說的內(nèi)容進行總結(jié)，該段的前面部分提及的是抗生素與過敏反應(yīng)之間的關(guān)系，即其對于人體免疫系統(tǒng)的影響，而該選項則是一個結(jié)果性的描述，即免疫系統(tǒng)變得過于敏感了，其可對前文中抗生素的作用進行總結(jié)說明。
