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進入英語學(xué)習(xí)論壇下載音頻 去聽寫專區(qū)一展身手

The weather warms and flowers blossom during spring, a delightful season for most of us.

But for those with seasonal allergies, spring is no fun.

Huang Tiequn, an allergic respiratory disease specialist at Beijing's China-Japan Friendship Hospital, has treated many patients suffering from allergic asthma in the past few weeks.

An allergy is an abnormally high sensitivity of the body to certain substances, such as pollens, foods and micro-organisms, Huang says.

When the body's immune system overreacts to such substances, the result can be symptoms such as red, painful or itchy skin, sneezing, runny nose, coughing, allergic conjunctivitis, nausea, vomiting and diarrhea.

Severe allergic reactions may include breathing difficulties that could be life-threatening.

Theoretically, anything alien to the body could be an allergen, and a sensitive individual could have many allergies, Huang notes.

Allergens can include medications, and dietary and environmental substances. Common allergens include penicillin, mushrooms, milk, eggs, seafood, fruits, insect stings, animal dander and pollen.

In spring, when flowers bloom and the air is full of pollen, this is a major cause of allergic asthma, Huang says.

The wide variety of freshly harvested vegetables and fruits also increases the incidence of food allergies, Huang adds, such as spinach, chives, leeks, nectarines, strawberries, pineapples and water chestnuts.

Foods rich in proteins, such as mushrooms, seaweed, shrimps and beans, are also linked with allergies.

"Once an allergy occurs, people should resort to medical treatment, in case the situation gets worse," Huang says.

Medicines such as decongestants may reduce the symptoms, but a complete cure lies in reducing the immune system's sensitivity to the allergens. Immunotherapy, for instance, or desensitization, works in this way.

When one allergen is identified, the patient would receive injections of progressively larger doses of the allergen. Over time, the patient will develop a resistance to the allergen.

Such treatments are most effective for skin allergies and allergic asthma, while it is less useful with food allergies. Professionals must supervise the treatment.

The doctor also warns that people can become allergic to something that they were previously not allergic to, with the change in their immune system caused by stress, fatigue and aging.

Therefore, a healthy lifestyle, such as exercising regularly and keeping good hygiene habits, may help avoid allergies.

Questions:

1. What are some symptoms of allergies?

2. What are some common allergens?

3. What else can contribute to allergies?

Answers:

1. Red, painful or itchy skin, sneezing, runny nose, coughing, allergic conjunctivitis, nausea, vomiting and diarrhea.

2. Penicillin, mushrooms, milk, eggs, seafood, fruits, insect stings, animal dander and pollen.

3. A change in immune system caused by stress, fatigue and aging.

去聽寫專區(qū)一展身手

（中國日報網(wǎng)英語點津 Helen 編輯）

About the broadcaster:

Nelly Min is an editor at China Daily with more than 10 years of experience as a newspaper editor and photographer. She has worked at major newspapers in the U.S., including the Los Angeles Times and the Detroit Free Press. She is also fluent in Korean.