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Monomelic Amyotrophy

Monomelic Amyotrophy  单肢肌肉萎缩

 

Monomelic amyotrophy (also known as MMA, Hirayama’s disease, Sobue diease or Juvenile nonprogressive amyotrophy) is an untreatable, focal, motor neuron disease that primarily affects young (15 – 25 year-old) males in India and Japan. MMA is marked by insidious onset of muscular atrophy, which stabilizes at a plateau after two to five years from which it neither improves nor worsens. There is no pain or sensory loss associated with MMA. Unlike other lower motor neuron diseases, MMA is not believed to be hereditary and fasciculations (involuntary muscle twitches) are rare.

Monomelic单肌萎缩 (又称MMA甲基丙烯酸甲酯平山郁夫症祖父江症少年无动态肌肉萎缩)是不治之症,这种聚焦的运动神经细胞疾病主要是影响印度和日本的青年男性(15 – 25岁)。甲基丙烯酸甲酯(MMA)的特点是隐匿性的肌肉萎缩发难,在二至五年后到了某一个高点就稳定下来,不再提高也不恶化。与甲基丙烯酸甲酯(MMA)相关的病症没有疼痛或丧失感觉,不像其他的较轻微运动神经元疾病,MMA不是遗传的,肌束颤动(不自主的肌肉抽搐)是罕见的。

EMG tests reveal loss of the nerve supply, or denervation, in the affected limb without conduction block (nerve blockage restricted to a small segment of the nerve). Increased sweating, coldness and cyanosis have been reported for a few patients, indicating involvement of the sympathetic nervous system.

肌电图测试(EMG)显示神经反应的丧失,或去神经化,在受影响的肢体里没有传导阻挡功能(神经阻塞被限制在神经的一小部分)。少数病人出现更多出汗,寒冷和紫绀的症状,表示跟交感神经系统有关。

While MMA will cause weakness and/or wasting in only one limb, EMG and NCV tests often show signs of reinnervation in the unaffected limbs.

虽然MMA会引起无力感亦或只有一肢废弃,肌电图(EMG)和神经传导速度测试(NCV)通常都显示出未受影响的四肢里有神经恢复知觉的迹象。

 

Contents  目录

·      Treatment 治疗处理

·      Prognosis 病症诊断

·      Epidemiology 流行病学

·      External links 外部链接

 

Treatment  治疗处理

There is no cure for MMA. Treatment consists of muscle strengthening exercises and training in hand coordination.

MMA无法治愈,对治办法包括加强肌肉的锻炼以及训练手的协调能力。

 

Prognosis  病症诊断

The symptoms of MMA usually progress slowly for one to two years before reaching a plateau, and then remain stable for many years. Disability is generally slight. Rarely, the weakness progresses to the opposite limb. There is also a slowly progressive variant of MMA known as O’Sullivan-McLeod syndrome, which only affects the small muscles of the hand and forearm and has a slowly progressive course.

MMA的症状通常都进展缓慢,一到两年才能达到一个高点,然后维持多年的稳定。残疾通常也是轻微的。虚弱的部份很少会蔓延到另一肢。但MMA也有一个缓慢渐进的变体,称为(O’Sullivan-McLeod)欧苏利文麦劳尔症候群,只影响了手和前臂的小肌肉,过程缓慢渐进。

 

Epidemiology  流行病学

MMA occurs in males between the ages of 15 and 25. Onset and progression are slow. MMA is seen most frequently in Asia, particularly in Japan and India; it is much less common in North America.

甲基丙烯酸甲酯(MMA)在15和25岁之间的男性身上发生。发病和进展过程都慢。甲基丙烯酸甲酯在亚洲最常见,尤其是在日本和印度,在北美就不普遍。

 

External links  外部链接

monomelic_amyotrophy at NINDS。NINDS的单肢肌肉萎缩

MND Association。MND协会

Overview at Washington University  华盛顿大学的概况

 

Categories  分类

  • Motor neurone disease  运动神经元疾病

—— END ——

 

Source > Wikipedia at en.wikipedia.org/wiki/Monomelic_amyotrophy

Translated by > BlogHost

Word Count > approx. 350 words in English

 

Osteology

April 21, 2012 Leave a comment

Osteology  骨骼学

 

Osteology is the scientific study of bones, practiced by osteologists. A subdiscipline of anatomy, anthropology, and archeology, osteology is a detailed study of the structure of bones, skeletal elements, teeth, morphology, function, disease, pathology, the process of ossification (from cartilaginous molds), the resistance and hardness of bones (biophysics), etc. often used by scientists with identification of human remains with regard to age, death, sex, growth, and development in a biocultural context.

骨骼学是一项科学研究,由骨科学家来做。这是解剖学,人类学和考古学的一个分支学科。骨科是一个详细研究骨骼结构,骨骼元素,牙齿,形态,功能,疾病,病理学,骨化过程(软骨模具),骨骼的阻力和硬度(生物物理学)等经常被科学家用来鉴定人类遗骸的年龄,死因,性别,成长,以及在生物文化背景下的发展。

Osteology and osteologists should not be confused with the alternative medical practice known as osteopathy and its practitioners, osteopaths.

骨骼学和骨科学家不应该跟另一个医学领域里的整骨及其从业人员混淆。

 

Methods 方法

A typical analysis will include:

  • an inventory of the skeletal elements present
  • a dental inventory
  • aging data, based upon epiphyseal fusion and dental eruption (for subadults) and deterioration of the pubic symphysis or sternal end of ribs (for adults)
  • stature and other metric data
  • ancestry
  • non-metric traits
  • pathology and/or cultural modifications

典型的分析包括:

  • 现成的骨骼元素清单
  • 牙科清单
  • 根据(未成年)骨骺融合和牙齿突长,以及(成人)耻骨愈合或肋骨的胸骨尾端的恶化得来的老化数据。
  • 身材和其他度量数据
  • 祖先族谱
  • 非度量的特征
  • 病理亦或文化

 

Applications 应用

Osteological approaches are frequently applied to investigations in disciplines such as forensic science, physical anthropology and archaeology, and has a place in research on topics including:

骨学方法通常都用在法医学,体质人类学和考古学等学科的调查,在以下课题的研究占有一定的地位:

  • Health  健康
  • Demography  人口
  • Diet  饮食
  • Disease  疾病
  • activity patterns  活动模式
  • physique  体质
  • genetics of early populations  早期人口的遗传
  • population migration  人口迁徙
  • Ancient warfare  古代战争
  • social inequality  社会不平等
  • identification of unknown remains  鉴定不明的遗骸
  • criminal investigations  刑事侦查
  • war crimes  战争罪

 

See also 另见

  • Osteometric points  骨量点

 

External Links 外部链接

  • British Association for Biological Anthropology and Osteoarchaeology

英国的生物人类学和骨骼考古学协会

 

Categories 分类

  • Osteology  骨骼学
  • Physical anthropology  体质人类学
  • Musculoskeletal system  肌肉骨骼
  • Anthropology  人类学

—— END ——

 

Source > Wikipedia at en.wikipedia.org/wiki/Osteology

Translated by > BlogHost

Word Count > approx.300 words in English

 

Baleen

February 29, 2012 1 comment

Baleen   鲸须

 

Baleen or whalebone is a filter-feeder system inside the mouths of baleen whales. The baleen system works when a whale opens its mouth underwater and then water pours into the whale’s mouth. The whale then pushes the water out, and animals such as krill are filtered by the baleen and remain as food source for the whale. Baleen is similar to bristles and is made of keratin, the same substance found in human fingernails and hair. Some whales, such as the bowhead whale, have longer baleen than others. Others whales, such as the gray whale, only use one side of their baleen. These baleen bristles are arranged in plates across the upper jaw of the whale.

鲸须鲸骨是须鲸嘴里的过滤喂食器。鲸须的系统运作原理是在鲸鱼在水里打开它的嘴巴让水灌入时才开始运作。鲸鱼把水排出去时,动物如磷虾类就被鲸须过滤留在体内成为食物来源。鲸须是角质材质的,类似刷毛,这类物质在人类的的指甲和头发上也有。一些鲸鱼如露脊鲸有比较长的鲸须。其他鲸如灰鲸只使用须的一边而已。这些须的刷毛就长在鲸鱼上颚的鲸须板上。

Depending on the species, a baleen plate can be 0.5 to 3.5 metres (1.6 to 11 ft) long, and weigh up to 90 kilograms (200 lb). Its hairy fringes are called baleen hair or whalebone-hair. They are also called baleen bristles, which in sei whales are highly calcified, calcification functioning to increase their stiffness. Baleen plates are broader at the gumline (base). The plates have been compared to sieves or Venetian blinds.

根据品种,鲸须板可以长达0.5到3.5米(1.6到11英尺),重达90公斤(200磅)。毛茸茸的边缘部份被称为须发或鲸发。他们也被称为鲸须刷毛,在鲸体内则高度钙化,钙化是为了提高其韧度。鲸须板在牙龈线(底盘)的部份比较宽大。这些鲸须板就像筛网或百叶帘。

 

Contents  目录

  • Etymology  词源
  • Evolution  进化
  • Filter feeding  滤食性能
  • Human uses  人类用途
  • As a habitat  栖息地
  • References  参考资料
  • Further reading  其他读物

 

Etymology  词源

The word “baleen” derives from Early Modern English word meaning “whale”. This in turn derives from the Latin balaena, related to the Greek phalaina – both of these also mean “whale”.

“鲸须”一词源自于早期的现代英语单词,意思是“ 鲸鱼 ”,也是出自拉丁文的balaena,跟希腊文的phalaina有关,两者的意思都是”鲸鱼”.

 

Evolution  进化

The oldest true fossils of baleen are only 15 million years old, but baleen rarely fossilizes, and scientists believe it originated considerably earlier than that. This is indicated by baleen-related skull modifications being found in fossils from considerably earlier, including a buttress of bone in the upper jaw beneath the eyes, and loose lower jaw bones at the chin. Baleen is believed to have evolved around thirty million years ago, possibly from a hard, gummy upper jaw, like the one a Dall’s porpoise has. In fact, it resembles baleen closely at the microscopic level.

鲸须最古老的化石只有1千5百万年,但鲸须很少变成化石,因此科学家相信它的起源更早。这一点可以从更早以前发现的有鲸须的鲸鱼头骨化石看出来,尤其是眼睛下方上颚骨里的一排骨头,以及下巴松动的下颚骨。科学家相信鲸须在大约三千万年前进化而成,有可能是从硬的上颚骨牙龈那里长出来,像达尔江豚也有的。 事实上,在微观层面上它更像鲸须。

Many early baleen whales also had teeth, but these were probably used only peripherally, or perhaps not at all (again like Dall’s porpoise, which catches squid and fish by gripping them against its hard upper jaw).

许多早期的须鲸也有牙齿,但这些都可能只是偶尔用到,或者完全不用(又像达尔江豚那样,只用来抓住鱿鱼和鱼压在硬上颚)。

 

Filter Feeding  滤食性能

A whale’s baleen plates play the most important role in its filter-feeding process. In order to feed, a baleen whale opens its mouth widely and scoops in dense shoals of prey (such as krill, copepods, small fish and sometimes birds that happen to be near the shoals), together with large volumes of water. It then partly shuts its mouth and presses its tongue against its upper jaw, forcing the water to pass out sideways through the baleen, thus sieving out the prey which it then swallows.

鲸鱼的鲸须板在这个滤食性过程中发挥最重要的作用。为了喂食,须鲸必须大开嘴巴,在佈满食物的浅滩里连同大量海水搜刮食物(如磷虾,桡足类,小鱼,有时是碰巧靠近浅滩的鸟)。然后,它关闭部份嘴巴用舌头压住上颚,迫使海水通过的须的两侧排出,以便滤出食物再吞下去。

 

Human Uses  人类用途

People formerly used baleen for making numerous items where flexibility and strength were required, including collar stiffeners, buggy whips and parasol ribs, and as corset stays. It was commonly used to crease paper; its flexibility kept it from damaging the paper. It was also occasionally used in cable-backed bows. Synthetic materials are now usually used for similar purposes, especially plastic and fibre glass. Baleen was frequently used in the 18th and early 19th centuries as the handle for silver punch or toddy ladles. It was chosen for this use because of its insulating qualities. Baleen plates are also used by indigenous people to create fine crafts.

以前人们使用鲸须的弹性和强度来制造许多东西,如衣领加强筋,越野车,遮阳伞的肋骨,和紧身胸衣。也常用来折纸痕,其灵活性不会损坏纸张。偶尔也用当支撑电缆的弓。现在的合成材料也用在类似用途,尤其是塑料和玻璃纤维。鲸须在18世纪和19世纪初普遍用来制作银色打孔器或椰汁杓,因为它的绝缘性质而被选用。鲸须板也被土著用来制造工艺用品。

 

As a Habitat  栖息地

Baleen serves as a habitat for some species from the gastropod families Pyropeltidae, Cocculinidae, Osteopeltidae and Neolepetopsidae.

鲸须也成为某些物种的栖息地,譬如腹足类家族的Pyropeltidae,Cocculinidae,Osteopeltidae以及Neolepetopsidae。

 

See Also  另见

  • John Henry Devereux South Carolina architect who used whale jaw bones to adorn the largest mansion on Sullivan’s Island.

南卡罗来纳州的建筑师John Henry Devereux约翰亨利德弗罗用鲸鱼颚骨来装饰Sullivan苏里曼岛上最大的豪宅。

  • Cetaceans   鲸类动物
  • Whale Products  鲸鱼产品

 

—— END ——

 

Source > Wikipedia at en.wikipedia.org/wiki/Baleen

Translated by > BlogHost

Word Count > approx. 630 words in English

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