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Everyfall, you need a new flu shot. Let's consider these vaccines² training ourimmune system, the recognize specific strains of flu. Identifying by two protein on the virus coat, hem³ agglutinin(血细胞凝集素) and neuraminidases(神经氨酸酶).

That's for the HN come from, H1N1. Problem is, thoseproteins are moving target, they mutatequickly. Once they do, your immune system can't recognize them. And you gotsomething like 2009 swineflu. As the strain flu shot never *primed us to fight.

To make more universal vaccine¹, we worked year after year. Researchers focused onsmaller, more stable protein, called M2. In human's strains, these proteinshardly change since the 1930s. Research engineer in the M2 vaccine and gave to mice, then they exposed the mice to lethaldoses to human, swine and bird flues.

All the vaccine micesurvived, they are unlucky counterparts, didn't. The research appears inJournal Molecule⁴ Therapy.

A good seasonal⁵ flu vaccine were still beat the M2 vaccine. But the M2 gives us insurance against a surprisedstrain. Well, it might worth a shot.

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1 vaccine
n.牛痘苗，疫苗；adj.牛痘的，疫苗的
参考例句：
The polio vaccine has saved millions of lives.脊髓灰质炎疫苗挽救了数以百万计的生命。 She takes a vaccine against influenza every fall.她每年秋季接种流感疫苗。

2 vaccines
疫苗，痘苗( vaccine的名词复数 )
参考例句：
His team are at the forefront of scientific research into vaccines. 他的小组处于疫苗科研的最前沿。 The vaccines were kept cool in refrigerators. 疫苗放在冰箱中冷藏。

3 hem
n.贴边，镶边；vt.缝贴边；(in)包围，限制
参考例句：
The hem on her skirt needs sewing.她裙子上的褶边需要缝一缝。 The hem of your dress needs to be let down an inch.你衣服的折边有必要放长1英寸。

4 molecule
n.分子，克分子
参考例句：
A molecule of water is made up of two atoms of hygrogen and one atom of oxygen.一个水分子是由P妈̬f婘̬ 妈̬成的。 This gives us the structural formula of the molecule.这种方式给出了分子的结构式。

5 seasonal
adj.季节的，季节性的
参考例句：
The town relies on the seasonal tourist industry for jobs.这个城镇依靠季节性旅游业提供就业机会。 The hors d'oeuvre is seasonal vegetables.餐前小吃是应时蔬菜。