首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
How to Solve Three Puzzles New knowledge and sophisticated diagnostic techniques are helping doctors recognize early signs o
How to Solve Three Puzzles New knowledge and sophisticated diagnostic techniques are helping doctors recognize early signs o
admin
2012-07-11
79
问题
How to Solve Three Puzzles
New knowledge and sophisticated diagnostic techniques are helping doctors recognize early signs of autism (孤独症), Alzheimer’s disease (痴呆症) and heart problems in women. Harvard experts report on the advances that are giving patients hope.
Detecting Autism
Early diagnosis of autism is critical because educational programs that build upon a child’s strengths and improve social skills may help sculpt the developing brain, minimizing the impact of the illness later in life. But spotting the disorder is hard since there is no test for it, although scientists are slowly uncovering gene abnormalities that make children vulnerable to autism. Last week The New England Journal of Medicine reported that a specific location on chromosome (染色体) 16 was the site of mutations responsible for some cases of autism.
For now, diagnosis depends on observing a child’s behavior. It’s a complex process, since no two cases are alike and signs range from mild to severe. Indeed, even though signs of autism may be apparent before their first birthday, most children aren’t diagnosed until the age of 3. That makes parents, who are so intimately familiar with their child’s behavior, perhaps the most effective diagnostic "tools." The American Academy of Pediatrics recently issued screening guidelines recommending that pediatricians engage parents in evaluating infants for autism. Even babies developing typically, the guidelines say, should be screened at set intervals, such as during the 9-, 18- and 24-month visits.
Healthy infants as young as 6 or 8 months do communicate and respond nonverbally to social cues. Most look up or turn at the sound of their names. By 12 months they typically babble and point at objects. By 16 months they say single words; by 24 months, two-word phrases. In contrast, children with autism seldom make meaningful eye contact or respond to familiar voices. They may never speak. Their play is often repetitive and characterized by limited imagination (neatly arranging crayons instead of coloring with them). Others may simply flap their hands in excitement or disappointment.
On their own, none of these signs means that a child has autism or another developmental disorder. Nevertheless, if your child has any of these signs, he or she merits evaluation. Although no treatments are curative, they can help children learn the skills they need to cope in a normal environment, achieve greater independence and have brighter futures.
The Alzheimer’s Mystery
Alzheimer’s disease, which begins years, even decades, before it causes symptoms, is a quietly ticking time bomb. But until recently doctors had no diagnostic test that could "hear" the ticking. Unfortunately, it didn’t matter much that Alzheimer’s couldn’t be spotted early — at a stage called mild cognitive impairment, or MCI — since there were no treatments. Today, however, there are new diagnostic tests that can detect Alzheimer’s at an early stage, and several disease-modifying drugs are in advanced clinical trials.
The brain shrinkage caused by Alzheimer’s can now be measured with volumetric magnetic resonance imaging (MRI). This technique takes a series of MRI brain scans and then uses sophisticated mathematical models to analyze the results. Most important, volumetric MRI enables researchers to identify subtle shrinkage in brain areas first affected by Alzheimer’s, such as the hippocampus, which is involved in memory.
Another technology in limited clinical use is fluoro-deoxy-glucose positron emission tomography (FDG-PET). Images produced by FDG-PET reveal patterns of glucose metabolism (葡萄糖新陈代谢) in the cerebral cortex, the site of abstract thought, reasoning and learning. Because active neurons guzzle glucose for energy, diminished uptake in a specific pattern can denote Alzheimer’s. In the research setting, scientists have even used FDG-PET to identify people who do not yet have Alzheimer’s but are at risk for developing it, or for developing mild cognitive impairment.
A different kind of PET-scan technology builds on recent discoveries about amyloid plaques and tau tangles, the neuron-killing proteins that accumulate in the brains of Alzheimer’s patients. Researchers at the University of Pittsburgh have developed Pittsburgh Compound-B, or PIB. When injected into the blood, this compound binds to amyloid plaques in the brain, allowing them to be detected on PET scans. PET scans with PIB clearly distinguish people with Alzheimer’s from healthy people. They may also help identify people with the progressive form of MCI.
Taking a different approach, other researchers are identifying early changes in the levels of particular brain proteins in cerebrospinal fluid. (The clear spinal fluid constantly bathes the brain and spinal cord.) Spinal-fluid levels of the protein tau are typically elevated in Alzheimer’s, and an altered version of the tau protein, known as phosphorylated tau, can be detected early in Alzheimer’s. Lowered spinal-fluid concentrations of an altered version of beta-amyloid, called A-42, are typical in Alzheimer’s and can also help identify people with mild cognitive impairment who are most likely to progress to Alzheimer’s.
Although all these new imaging and biochemical developments are individually promising, the combination of several different imaging tests and biochemical markers may yield the most accurate diagnosis. For example, scientists at the New York University School of Medicine have reported that combining volumetric MRI of the hippocampus with spinal-fluid measures of phosphorylated tau and isoprostane — a marker of oxidative stress — improved diagnostic accuracy in identifying people with mild cognitive impairment who are most likely to progress to Alzheimer’s.
Heart Disease in Women
When it comes to diagnosing the most common kind of heart disease, some cardiologists share Henry Higgins’s lament in My Fair Lady: "Why can’t a woman be more like a man?" That’s because many women don’t have the typical symptoms, like crushing chest pain and shortness of breath brought on by physical activity or stress. Instead, they have diffuse discomfort in the chest, unusual exhaustion or depression without an apparent reason. To make matters worse, the tests considered best at diagnosing coronary-artery disease generally don’t work as well for women as they do for men. As a result, an alarming number of women with heart disease go undiagnosed and untreated despite repeated visits to the doctor and the emergency room.
Blood flows to heart muscle first through large arteries (the coronary arteries) and then through a branching network of smaller blood vessels. The symptoms of heart disease, in men or women, often result from cholesterol-filled plaques that can slow and completely block the flow of blood to the heart muscle. This type of heart disease, which has been recognized for a century, can be seen with tests such as coronary angiograms (or arteriograms) and, less well, with noninvasive tests such as special CT and MRI scans.
In just the past decade, researchers have learned that many women with chest pain and other symptoms of heart disease have a condition called coronary micro-vascular disease, which affects the heart’s smallest arteries. This fundamentally different form of heart disease is as common and as costly as all female-specific cancers combined, affecting as many as 3 million American women.
Many doctors have not yet heard about coronary micro-vascular disease. Currently, the most definitive test involves measuring coronary-artery flow reserve or coronary reactivity. It involves threading an ultra thin wire with blood-flow sensors at the tip deep into a coronary artery. Blood flow in the artery is then measured before and after injections of one or more medications that should cause the micro-vessels to dilate. An alternative, noninvasive way of detecting microvascular disease is with cardiac MRI. This scan measures the amount of blood flowing into the heart muscle before and after the heart is infused with a drug that dilates the micro-vessels. As with the coronary-reactivity test, if blood flow does not increase, there is disease of the micro-vessels.
If you are a woman with recurrent chest pain or discomfort, shortness of breath, uhexplainable exhaustion and depression, you may need special evaluation even if you have clear arteries on an angiogram. If your doctor says there’s nothing wrong, ask for a second opinion at one of a growing number of women’s cardiovascular-care centers. You may have coronary micro-vascular disease.
A woman needs special evaluation if she has some symptoms, such as recurrent chest pain and unexplainable______.
选项
答案
exhaustion and depression
解析
空前的形容词unexplainable表明,本空应填一名词(短语)。题干中的A woman needs special evaluation对应该句中的you may need special evaluafion,if she has与If you are a woman with对应,such as后举例提到的症状与该句提到的recurrent chest pain和unexplainable exhaustion and depression对应,故答案为exhaustion and depression。
转载请注明原文地址:https://kaotiyun.com/show/Fzb7777K
0
大学英语六级
相关试题推荐
Directions:Forthispart,youareallowed30minutestowriteashortessayentitledDoCollegeStudentsNeedCareerOrientatio
TheU.S.governmentisaskingAmericanstoeatlessandexercisemoreinanefforttostemthecountry’sincreasingepidemicof
TheU.S.governmentisaskingAmericanstoeatlessandexercisemoreinanefforttostemthecountry’sincreasingepidemicof
Onecalledherbossa"bitchfromhell"whileanotheradmitted"lyingthroughhisteeth"atinterview.BoththeBritishjob【B1】_
ThestateofHawaiiturns50thisyear.Peoplethereshouldbehappy.Butit’shard.Theeconomyisreallybad.Thehousing
ThestateofHawaiiturns50thisyear.Peoplethereshouldbehappy.Butit’shard.Theeconomyisreallybad.Thehousing
A、Howtowinthebattleofstaffcuttinginthecompany.B、Howtoavoidfailuresinpersonalinvestment.C、Howtoturnjobredun
Intheearly20thcentury,fewthingsweremoreappealingthanthepromiseofscientificknowledge.Inaworldstrugglingwithr
Intheearly20thcentury,fewthingsweremoreappealingthanthepromiseofscientificknowledge.Inaworldstrugglingwithr
A、Theyonlylikethemselves.B、Theyarenotbotheredbyfailures.C、Theyknowhowtobecomebetter.D、Theycanalwaysmakeadif
随机试题
女性,18岁,体检发现心脏杂音来诊。平时不能耐受较大的体力活动,无双下肢水肿及夜间呼吸困难史,易感冒。查体:血压:130/80mmHg,心率90次/分。S1↓,S2稍↑。A:SM3/6反流样向左腋下传导,L4、5可闻收缩期Click音,下蹲位站立后Cli
红细胞上无H抗原称为
下列方法中,对Rh血型系统较为敏感的是
制备肠溶胶囊时,使用甲醛处理的目的是
下列关于价值工程的含义描述不正确的是( )。
科学管理的标志之一是()。
在下列账目中,出纳人员可以登记的是()。
王某现年17岁,高二学生,平时创新能力极强,其研究创造的一个小发明获得专利,并且经济价值较高。专利权的申请、使用和由此所获取的收入的处理一概由王某的父亲予以安排,王某的父亲从事的下列各种行为中,违背了监护责任的是()。
A、 B、 C、 D、 AA项可由左侧图形折成;B项,直线应与阴影相接,错误;C项,左侧面中三角形应含阴影,错误;D项,右侧面中阴影三角形应在上部,错误。
2017年4月1日,中共中央、国务院决定在此设立的国家级新区。设立雄安新区()
最新回复
(
0
)