英语 英语 日语 日语 韩语 韩语 法语 法语 德语 德语 西班牙语 西班牙语 意大利语 意大利语 阿拉伯语 阿拉伯语 葡萄牙语 葡萄牙语 越南语 越南语 俄语 俄语 芬兰语 芬兰语 泰语 泰语 泰语 丹麦语 泰语 对外汉语

VOA慢速英语2013 AS IT IS - A discovery that could save the lives of millions of newborns

时间:2013-04-02 09:07来源:互联网 提供网友:nan   字体: [ ]
    (单词翻译:双击或拖选)

 

AS IT IS - A discovery that could save the lives of millions of newborns

Welcome to AS IT IS, from VOA Learning English. I’m Christopher Cruise.

Today, it’s all about saving babies and preventing pregnancy1

Kelly Jean Kelly will report on a discovery that could save the lives of millions of newborns.

And I’ll tell you about a study that suggests a possible link between stress in pregnancy and autism or schizophrenia.

But first, we bring you news about a study that predicts a huge unmet need for modern contraceptives in the coming years.

The study predicts millions of married women will not be able to get them over the next few years. Researchers estimate that, by 2015, modern contraceptive methods will not be available to more than 230 million women worldwide who want to use them.Onka Dekker tells us more…

Researchers examined contraceptive use in 194 countries between 1990 and 2010. They designed a mathematical model to estimate the number of married women who used modern, effective contraceptives. These family-planning methods include hormonal2 medicines --drugs that use hormones4 produced by the body. The study estimated the number of women who wanted to use such medicines to prevent pregnancy. But these women were instead using older, traditional birth control methods that sometimes fail.

The model showed that this “unmet need” for modern birth control had decreased over the past 20 years. It also showed a worldwide increase in family planning methods based on hormone3 medicines, such as The Pill and injections. Yet the researchers say the growing world population will result in a greater need for modern family planning methods by 2015. They estimate that 233 million women will not be able to find or use these contraceptive methods.

Ann Biddlecom leads the United Nations Fertility and Family Planning office in New York. She was the main writer of the report. She says there is a lack of support in many countries for family-planning services.

“It comes to, you know, having access not only to the method itself but also better access to quality counseling and options for other kinds of methods to use if one particular method is not working for you.”

She says that, by 2010, the greatest improvements in availability of hormonal birth control methods came in Central America and North Africa. But, she said fewer than one in five married women used any sort of effective birth control in parts of central and western Africa.

Ann Biddlecom says the study only involved married women. She believes the actual number of women needing modern birth control methods by 2015 will be more than 233 million estimated by the researchers.

I’m Onka Dekker.

American researchers have identified a protein that may be linked to neurodevelopmental disorders5 like autism and schizophrenia. The researchers say the level of the protein is affected6 by serious stress women experience during their pregnancy.

The researchers studied women who experienced stress --that is, physical or emotional tension --during pregnancy. They found that such women sent lower levels of a protein to their developing fetuses8 through the placenta than other women. The lowest levels were found in the placentas of boys.

The placenta connects the fetus7 to the wall of the uterus. It passes blood, oxygen and nutrients9 to the unborn child through the mother’s blood.

Tracy Bale is a professor of neurology at the University of Pennsylvania in Philadelphia. She also was the lead researcher in the study. She says the placenta acts as a filter, sorting liquids and other materials within a pregnant woman.

“So, it has genes10 that are expressed that produce these functions. But those genes can change in response to mom’s stress, mom’s dietary changes, mom’s immune responses, etc.”

Autistic individuals have poor communication and social interaction skills. People with schizophrenia imagine unreal things or situations, and have difficulty connecting with people and their environment.

The researchers knew that the two disorders affect males more often and more severely11 than females. So, Dr. Bale and her team began looking for a protein that might explain why that is.

Researchers caused stress in mice during their first week of pregnancy. One week would be the same as the first three months of a human pregnancy. The researchers used the smell of animals that attack mice and noises the mice had not heard before. They then compared the placentas of the stressed mice to those of unstressed mice.

They discovered a protein, called OGT, which seems to be present in higher levels in the female placentas than in the placentas of males. They found that OGT levels were lower in the placentas of the stressed mice compared to those lacking emotional or physical tension.

Investigators12 also found that mice with half the normal amount of OGT had changes in hundreds of different genes known to be involved in brain development. Researchers also examined human placentas after birth and found lower levels of the protein in male placental tissue.

Dr. Bale cannot say for sure whether the protein affects the neurodevelopment of humans. But she says the discovery of OGT could lead to a test to identify babies at increased risk for autism and schizophrenia because of stress during pregnancy.

“You would know which babies to follow to keep an eye on them, to determine if they are at a greater risk. And they may be presenting earlier with different stress-reactivity levels, behavioral changes, etcetera, that would predispose them.”

The study was the work of researchers at the University of Pennsylvania in Philadelphia. A report on the pregnancy stress protein was published in Proceedings13 of the National Academy of Sciences.

Researchers have discovered a way to possibly help protect the health of newborns when they are most at risk of infection. The discovery could save the lives of millions of babies around the world every year.

Kelly Jean Kelly explains.

Each year, bacterial14 and viral infections kill more than two million babies under the age of six months. These newborns are at risk because their natural defenses for fighting disease are too underdeveloped to be helped by vaccines16.

That is why vaccines are usually not given to babies less than two months old. These include vaccinations17 to guard against rotavirus and polio, which children receive as they grow up. Yet in many countries, birth might be the only time a child will have contact with a health-care worker.

Ofer Levy18 studies infectious diseases at Harvard Medical School in Boston, Massachusetts. He says researchers have been looking for a way to protect newborns.

“So we want to design a super vaccine15 that you can give at birth and maybe even get single-shot protection or maybe fewer shots needed. But also by giving it early in life, you close the window of vulnerability inherent to the current vaccine schedule.”

Dr. Levy and researchers at Harvard and Boston Children’s Hospital have identified a small man-made molecule19, called VTX-294. The molecule produces a strong immune response in protective white cells taken from the umbilical-cord blood of newborns.

It activated20 a kind of white blood cell, which is necessary for a vaccine to work. These cells help the body’s natural defenses recognize and destroy disease-causing microorganisms.

Dr. Levy says VTX-294 proved to be stronger than anything tested yet in studies to strengthen newborns’ immune responses.

“When we say potent21, it means you can add very little amount of this compound and get a very powerful response.”

He says researchers are also looking at whether the molecule can strengthen the immune systems of people with cancer so that anti-cancer medicines can be more effective.

A report describing VTX-294 was published in the journal PLOS One.

I’m Christopher Cruise, and that’s “As It Is” in Special English from The Voice of America.


点击收听单词发音收听单词发音  

1 pregnancy lPwxP     
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。
2 hormonal Fcpx6     
adj.激素的
参考例句:
  • Some viral diseases are more severe during pregnancy, probably tecause of hormonal changes. 有些病毒病在妊娠期间比较严重,可能是由于激素变化引起的。
  • She underwent surgical intervention and a subsequent short period of hormonal therapy. 他接受外科手术及随后短暂荷尔蒙治疗。
3 hormone uyky3     
n.荷尔蒙,激素,内分泌
参考例句:
  • Hormone implants are used as growth boosters.激素植入物被用作生长辅助剂。
  • This hormone interacts closely with other hormones in the body.这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。
4 hormones hormones     
n. 荷尔蒙,激素 名词hormone的复数形式
参考例句:
  • This hormone interacts closely with other hormones in the body. 这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。
  • The adrenals produce a large per cent of a man's sex hormones. 肾上腺分泌人体的大部分性激素。
5 disorders 6e49dcafe3638183c823d3aa5b12b010     
n.混乱( disorder的名词复数 );凌乱;骚乱;(身心、机能)失调
参考例句:
  • Reports of anorexia and other eating disorders are on the increase. 据报告,厌食症和其他饮食方面的功能紊乱发生率正在不断增长。 来自《简明英汉词典》
  • The announcement led to violent civil disorders. 这项宣布引起剧烈的骚乱。 来自《简明英汉词典》
6 affected TzUzg0     
adj.不自然的,假装的
参考例句:
  • She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
  • His manners are affected.他的态度不自然。
7 fetus ekHx3     
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。
8 fetuses eae25b106f4ed68558631a5bf44c9293     
n.胎,胎儿( fetus的名词复数 )
参考例句:
  • DNA was extracted from fetuses at mid-gestation, about 10 days past conception. DNA从受孕大约10天后的中期妊娠胚胎中提取。 来自互联网
  • Brucellosis is a disease that causes fetuses to abort in cattle. 普鲁士菌病是一种可以导致牲畜胎儿夭折的疾病。 来自互联网
9 nutrients 6a1e1ed248a3ac49744c39cc962fb607     
n.(食品或化学品)营养物,营养品( nutrient的名词复数 )
参考例句:
  • a lack of essential nutrients 基本营养的缺乏
  • Nutrients are absorbed into the bloodstream. 营养素被吸收进血液。 来自《简明英汉词典》
10 genes 01914f8eac35d7e14afa065217edd8c0     
n.基因( gene的名词复数 )
参考例句:
  • You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因,所以能够活得很长。 来自《简明英汉词典》
  • Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪
11 severely SiCzmk     
adv.严格地;严厉地;非常恶劣地
参考例句:
  • He was severely criticized and removed from his post.他受到了严厉的批评并且被撤了职。
  • He is severely put down for his careless work.他因工作上的粗心大意而受到了严厉的批评。
12 investigators e970f9140785518a87fc81641b7c89f7     
n.调查者,审查者( investigator的名词复数 )
参考例句:
  • This memo could be the smoking gun that investigators have been looking for. 这份备忘录可能是调查人员一直在寻找的证据。
  • The team consisted of six investigators and two secretaries. 这个团队由六个调查人员和两个秘书组成。 来自《简明英汉词典》
13 proceedings Wk2zvX     
n.进程,过程,议程;诉讼(程序);公报
参考例句:
  • He was released on bail pending committal proceedings. 他交保获释正在候审。
  • to initiate legal proceedings against sb 对某人提起诉讼
14 bacterial dy5z8q     
a.细菌的
参考例句:
  • Bacterial reproduction is accelerated in weightless space. 在失重的空间,细菌繁殖加快了。
  • Brain lesions can be caused by bacterial infections. 大脑损伤可能由细菌感染引起。
15 vaccine Ki1wv     
n.牛痘苗,疫苗;adj.牛痘的,疫苗的
参考例句:
  • The polio vaccine has saved millions of lives.脊髓灰质炎疫苗挽救了数以百万计的生命。
  • She takes a vaccine against influenza every fall.她每年秋季接种流感疫苗。
16 vaccines c9bb57973a82c1e95c7cd0f4988a1ded     
疫苗,痘苗( vaccine的名词复数 )
参考例句:
  • His team are at the forefront of scientific research into vaccines. 他的小组处于疫苗科研的最前沿。
  • The vaccines were kept cool in refrigerators. 疫苗放在冰箱中冷藏。
17 vaccinations ed61d339e2970fa63aee4b5ce757cc44     
n.种痘,接种( vaccination的名词复数 );牛痘疤
参考例句:
  • Vaccinations ensure one against diseases. 接种疫苗可以预防疾病。 来自《简明英汉词典》
  • I read some publicity about vaccinations while waiting my turn at the doctor's. 在医生那儿候诊时,我读了一些关于接种疫苗的宣传。 来自《简明英汉词典》
18 levy Z9fzR     
n.征收税或其他款项,征收额
参考例句:
  • They levy a tax on him.他们向他征税。
  • A direct food levy was imposed by the local government.地方政府征收了食品税。
19 molecule Y6Tzn     
n.分子,克分子
参考例句:
  • A molecule of water is made up of two atoms of hygrogen and one atom of oxygen.一个水分子是由P妈̬f婘̬ 妈̬成的。
  • This gives us the structural formula of the molecule.这种方式给出了分子的结构式。
20 activated c3905c37f4127686d512a7665206852e     
adj. 激活的 动词activate的过去式和过去分词
参考例句:
  • The canister is filled with activated charcoal.蒸气回收罐中充满了活性炭。
21 potent C1uzk     
adj.强有力的,有权势的;有效力的
参考例句:
  • The medicine had a potent effect on your disease.这药物对你的病疗效很大。
  • We must account of his potent influence.我们必须考虑他的强有力的影响。
本文本内容来源于互联网抓取和网友提交,仅供参考,部分栏目没有内容,如果您有更合适的内容,欢迎点击提交分享给大家。
------分隔线----------------------------
TAG标签:   VOA慢速英语  million
顶一下
(2)
100%
踩一下
(0)
0%
最新评论 查看所有评论
发表评论 查看所有评论
请自觉遵守互联网相关的政策法规,严禁发布色情、暴力、反动的言论。
评价:
表情:
验证码:
听力搜索
推荐频道
论坛新贴