(单词翻译:单击)
听力文本
Scientists Explore How Cannabis May Fight Psychosis
British scientists have found how a substance in the cannabis plant acts in the brain to reduce abnormal activity in patients at risk of psychosis.
Their findings suggest that the substance could be used in a possible treatment for the condition.
Cannabis, also known as marijuana, is illegal to grow, sell or use in many countries. Using powerful forms of cannabis can increase a person's chances of developing psychosis. But the substance the researchers studied, the chemical cannabidiol, appears to have the opposite effect.
Cannabidiol, or CBD, is non-intoxicating. That means it is unlike drugs or alcoholic products, which can affect the user's judgement or behavior.
CBD is the same cannabis substance that has also been shown to help patients with epilepsy, a disorder of the nervous system. This led to the approval in the United States of a cannabis-based drug, a specially processed form of CBD, in June.
Earlier research at King's College London had shown that CBD seemed to block the effects of tetrahydrocannabinol, the intoxicating substance in cannabis. But how this happened was a mystery.
Now, King's College researchers say they have more evidence of the health benefits of CBD.
Sagnik Bhattacharyya and his team gave 33 young people capsules containing the substance. All 33 subjects were experiencing signs of psychosis, although they had not been shown to have the full-blown mental condition.
The researchers studied images from the brains of the young people. They found that taking CBD capsules reduced abnormal activity in three areas of the brain: the striatum, medial temporal cortex and midbrain.
Abnormal activity in all three areas has been linked to the development of psychotic disorders, such as schizophrenia.
Most current anti-psychotic drugs target the chemical dopamine. The brain uses dopamine to send signals from one nerve cell to another. But CBD works in a different way.
One major difference is that the body has an easier time dealing with CBD than other substances. CBD is less likely to cause harmful side effects, such as weight gain and other health problems linked to existing medicines.
Bhattacharyya told the Reuters news agency, "One of the reasons CBD is exciting is because it is very well tolerated compared to the other anti-psychotics we have available."
"There is an urgent need for a safe treatment for young people at risk of psychosis," he added.
The Institute of Psychiatry, Psychology and Neuroscience at King's College now plans a 300-patient clinical trial of CBD as a treatment.
Researchers plan to start identifying subjects for the clinical trial in early 2019.
The latest findings show the complexity of the combination of chemicals found within the marijuana plant. They come at a time when many countries are beginning to make their laws against cannabis less severe.
I'm Pete Musto.
重点解析
重点讲解：
1. at risk of 处境危险；有风险的；在危险中；
It says people are at risk of getting ill and dying from waterborne diseases including dysentery and diarrhea.
人们面临着染上疾病和死于包括痢疾，腹泻等水传染性疾病的危险。
2. be linked to 与……有联系；
The demands of work are often linked to the kind of business you work for.
工作需求经常和你从事的工作种类相关。
3. be likely to do sth. 可能（做…）的；有（…）倾向的；
Some jobs are quite likely to have a negative spillover into family life.
有些工作很可能会对家庭生活产生不良影响。
4. compared to 与…相比；和…比起来；
It sounds difficult, but compared to full-time work it was a cinch.
这听上去有难度，可是比起全职工作来，就是小意思了。
参考译文
科学家探索大麻如何能对抗精神病
英国科学家发现，大麻植物中的一种成分在大脑中的表现可以减少存在精神病风险患者的反常活动。
他们的研究表明，这种成分可以被用在对抗该疾病的可能的治疗方法中。
在许多国家，种植、销售或使用大麻属非法行为。服用烈性大麻可能会增加人们患精神病的风险。但是，研究人员研究的那种成分，即化学物质大麻二酚，似乎会产生相反的作用。
大麻二酚（简称CBD）是无精神活性成分。这意味着该成分不同于可以影响服用者判断或行为的毒品和酒类产品。
大麻二酚是大麻中被证明有助于癫痫患者的成分，癫痫是一种神经系统紊乱的疾病。因为得到证实，美国在今年6月批准了一种以大麻为基础的药物，该药物是大麻二酚的一种特殊加工形式。
伦敦国王学院的早期研究显示，大麻二酚似乎可以阻止四氢大麻酚的影响，四氢大麻酚是大麻植株中的精神活性成分。但是为何大麻二酚有这样的作用在当时还是个谜。
现在，国王学院的研究人员说，他们掌握了更多能证明大麻二酚有益于健康的证据。
萨格尼克·巴塔查亚和团队给33名年轻人提供了含有有大麻二酚的胶囊。所有33名实验对象均出现过精神病的症状，尽管他们未被证明患有确定的精神疾病。
研究人员研究了这些年轻人的脑部图像。他们发现，服用大麻二酚胶囊可以减少大脑中三个区域的反常活动：这三个区域分别是纹状体、内侧颞叶皮层和中脑区。
这三个区域的反常活动与精神分裂症等精神疾病的发展有关。
目前市面上的大多数抗精神病药物的研发焦点集中在化学物质多巴胺身上。大脑通过多巴胺从一个神经细胞向另一个神经细胞传递信号。但是大麻二酚以一种不同的方式发挥作用。
其中一个主要的不同点在于，与其他物质相比，身体更容易处理大麻二酚。大麻二酚不太可能引发有害的副作用，比如体重增加和其他与目前市面上销售的药物有关的健康问题。
巴塔查亚对路透社表示，“大麻二酚令人激动的其中一个原因是，相比于其他抗精神病药物，其有更大的耐受性。”
他补充说，“存在患精神病风险的年轻人迫切需要一种安全的治疗方式。”
现在，国王学院精神病学、心理学和神经科学研究所计划对300名患者展开临床试验，测试大麻二酚作为治疗方式的功效。
研究人员计划在2019年年初开始确定临床试验的实验对象。
这项最新研究证明了在大麻植物中发现的这种化学物质组合的复杂性。他们公布研究结果时，正值许多国家开始制定法律，反对大麻危害并不严重这种说法。
皮特·穆斯托报道。
译文为可可英语翻译，未经授权请勿转载！
