医生首次打破人类血脑保护屏障，对脑癌施以药物治疗。其它大脑疾病，比如，老年痴呆症也可以用同样方法进行治疗。以下是 BBC Michelle Roberts 发回的报道：

The blood-brain barrier does a good job of keeping toxins out. But this tightly-packed layer of cells which separates the brain from its blood vessels is a hindrance if you want to deliver drugs into the brain.

The patient – 56-year-old Bonny Hall from Canada – had a brain tumour that was growing in size despite conventional treatment and so she was given an intravenous infusion of chemotherapy along with a small dose of microbubbles. A focus beam of ultrasound was then applied to her skull to make the bubbles vibrate and punch holes in the blood-brain barrier.

Mrs Hall's neurosurgeon Dr Todd Mainprize says the procedure went well but more tests and safety checks are needed.

Another six to ten patients will take part in a safety trial to check for any side effects. If it goes well, the technique could eventually be used to treat other brain conditions, such as dementia, as well as cancer.

词汇表

toxins 毒素
hindrance 障碍，阻碍物
conventional 传统的
chemotherapy 化学疗法
ultrasound 超声波
procedure 手术，程序
eventually 最终，终将

测验

请听报道并回答下列问题。

1. What does the barrier between the blood vessels and the brain prevent?

2. What helps to open holes in the brain barrier?

3. True or false? Doctors are confident the technique is safe.

4. Which conditions might be treated by using this technique? 

答案

1. What does the barrier between the blood vessels and the brain prevent?
It prevents toxins from going into the brain.

2. What helps to open holes in the brain barrier?
Small bubbles which are injected inside the blood vessels and then vibrate when a beam of ultrasound is used.

3. True or false? Doctors are confident the technique is safe.
False. Mrs Hall's neurosurgeon Dr Todd Mainprize says more tests are safety checks are needed.

4. Which conditions might be treated using this technique?  
Cancer and dementia.