题干

直接注射抗体或注射疫苗都可以使人体获得免疫。下图是某人获得抗破伤风芽孢杆菌抗体的两种途径及其抗体的变化情况。下列有关说法正确的是(  )

A:途径①注射的是破伤风疫苗

B:当破伤风芽孢杆菌第一次侵入人体时,进行免疫预防的有效途径是途径①

C:正常情况下,途径②曲线在7天后逐渐下降,主要是记忆细胞的数目减少造成的

D:破伤风芽孢杆菌再次侵入人体内时,与上图相比,人体内抗体出现峰值的时间比途径②晚

上一题 下一题 0.0难度 选择题 更新时间:2019-09-20 04:10:47

答案(点此获取答案解析)

B

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阅读短文,根据短文内容,从短文后的五个选项中,选出能填入空白处的最佳选项。选项中有一项为多余选项。
    David Beckham was born on 2nd May, 1975, in London. When he was a young boy, he played football whenever he had the chance. Sometimes he would go and watch a game with his friends.____ . This led to him going for a visit to a football training camp in Spain. As a boy at secondary school he played for not only his school but also his country team.
On 8th July, 1991, he became a member of Manchester United.____ . On 2nd April, 1995, he played his first major football league game against Leeds United. During 1995 and 1996, David became a regular member of the team and Manchester United won in both seasons, with David scoring many goals.
____ . In the first game of the 1996/7 season, he scored an amazing goal from beyond the halfway line. Seeing the goalkeeper a little way out of his goal, David sent the ball over the goalkeeper's head and into the goal. He continued to score astonishing goals, especially from free-kicks.
    David Beckham is a great player, but he is different from most other players. He has a real love for football. ____ . He is always on the move with the ball or running to pick up a pass from another team member. He also has his feet on the ground and behaves in a very natural and relaxed way.

A. David Beckham is 180 cm tall and weighs 47kg
B. He won a prize at the age of twelve
C. When he is training, he never rests
D. David Beckham became very famous overnight
E. This means that he could practice football as much as he wanted to