VOA标准英语2013--Folic Acid Supplements Shown To Reduce Risk Of Autism

Folic Acid Supplements Shown To Reduce Risk Of Autism

Green, leafy vegetables, fruits and nuts naturally contain folate, a B vitamin that helps the body make healthy new cells.  Most pre-natal vitamins include folic acid because it protects against defects in the formation of the neural¹ tube, the precursor² to the central nervous system.
Dr. Pal³ Suren is with the Norwegian Institute of Public Health:
“The neural tube is the origin of the human brain in the fetus⁴ and closes very early in development, and the neural tube defect is when this tube doesn’t close properly," said Suren..
Neural tube defects include spina bifida, a defect of the spine⁵, as well as some brain defects.  Since taking folic acid supplements before or right after becoming pregnant prevents these defects, Dr. Suren and his colleagues wanted to find out if the supplements could also prevent autism. They asked thousands of pregnant women to record all dietary supplements they took.  After the children were born, the researchers reviewed the rate of autism. 
“We went back to the data we had from early pregnancy⁶ and compared those mothers who had taken folic acid to those who hadn’t taken any folic acid," he said.
They found that the women who took folic acid supplements in early pregnancy had a 40 percent reduction in the risk of having a child with autism.  But for those who started taking it in mid-pregnancy, there was no reduced risk. Dr. Ezra Susser of Columbia University was one of the co-authors.
“There’s a sensitive period in which folic acid supplements need to be taken in order to reduce the risk of autism," said Susser. "The period begins before pregnancy and continues approximately two months after pregnancy.” 
A recent survey conducted by the March of Dimes⁷ found that less than 30 percent of American women are aware that folic acid helps to prevent birth defects.
The March of Dimes' Dr. Ed McCabe says this is the result of two problems.
"Many pregnancies⁸ are unplanned, so women aren't thinking they are going to become pregnant, and therefore [that] they need to be on folic acid," said McCabe. "And then a lot of women don't know the importance of folic acid when they are becoming pregnant."
The March of Dimes hopes the new research will raise public awareness⁹ of the critical role folic acid plays in protecting babies' developing brains. The study was published in The Journal of the American Medical Association.

1 neural   

adj.神经的，神经系统的

参考例句：

• The neural network can preferably solve the non- linear problem.利用神经网络建模可以较好地解决非线性问题。
• The information transmission in neural system depends on neurotransmitters.信息传递的神经途径有赖于神经递质。

2 precursor   

n.先驱者；前辈；前任；预兆；先兆

参考例句：

• Error is often the precursor of what is correct.错误常常是正确的先导。
• He said that the deal should not be seen as a precursor to a merger.他说该笔交易不应该被看作是合并的前兆。

3 pal   

n.朋友，伙伴，同志；vi.结为友

参考例句：

• He is a pal of mine.他是我的一个朋友。
• Listen,pal,I don't want you talking to my sister any more.听着，小子，我不让你再和我妹妹说话了。

4 fetus   

n.胎，胎儿

参考例句：

• In the fetus,blood cells are formed in different sites at different ages.胎儿的血细胞在不同时期生成在不同的部位。
• No one knows why a fetus is not automatically rejected by the mother's immune system. 没有人知道为什么母亲的免疫系统不会自动排斥胎儿。

5 spine   

n.脊柱，脊椎；(动植物的)刺；书脊

参考例句：

• He broke his spine in a fall from a horse.他从马上跌下摔断了脊梁骨。
• His spine developed a slight curve.他的脊柱有点弯曲。

6 pregnancy   

n.怀孕，怀孕期

参考例句：

• Early pregnancy is often accompanied by nausea.怀孕早期常有恶心的现象。
• Smoking during pregnancy increases the risk of miscarriage.怀孕期吸烟会增加流产的危险。

7 dimes   

n.（美国、加拿大的）10分铸币( dime的名词复数 )

参考例句：

• Pennies, nickles, dimes and quarters are United States coins. 1分铜币、5分镍币、1角银币和2角5分银币是美国硬币。 来自《简明英汉词典》
• In 1965 the mint stopped putting silver in dimes. 1965年，铸币厂停止向10分硬币中加入银的成分。 来自辞典例句

8 pregnancies   

怀孕，妊娠( pregnancy的名词复数 )

参考例句：

• Since the wartime population needed replenishment, pregnancies were a good sign. 最后一桩倒不失为好现象，战时人口正该补充。
• She's had three pregnancies in four years. 她在四年中怀孕叁次。

9 awareness   

n.意识，觉悟，懂事，明智

参考例句：

• There is a general awareness that smoking is harmful.人们普遍认识到吸烟有害健康。
• Environmental awareness has increased over the years.这些年来人们的环境意识增强了。