每个季度都要制造新的流感疫苗是因为流感病毒会不断地变化从而逃避宿主(无论是人类、鸟类还是其他动物)免疫防线的攻击。
New flu vaccines need to be made each season because the viruses are constantly changing so as to avoid attack by host immune defences - whether in birds, humans or other animals.
那些在记忆测试中表现良好的人，其体内的免疫球蛋白 A 水平会升高。免疫球蛋白 A 是一种抗体，是人体抵御细菌的第一道防线。
Those who did well on the memory test had an increase in levels of immunoglobulin A, an antibody that's the body's first line of defense against germs.
这就削弱了免疫系统的下一道称为适应性免疫反应的防线。
This weakens the immune system's next line of defense, known as the adaptive immune response.
应用推荐