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专业术语—口腔生理学术语H2(英文详解)

时间:2006-06-21 16:00:00

(单词翻译:单击)

    Hyaluronic acid - the largest glycosaminoglycan known, it plays an important role of restricting the flow of water in tissues, particularly in synovial fluid where it acts as a lubricant..

    Hydrogen bonds - a weak force holding two molecules2 containing hydrogen together, each of which has a covalent bond with another atom. For example, water is a molecule1 made up of two hydrogen atoms attached covalently to an oxygen atom. The hydrogen proton is however not completely balanced and is still attracted to the oxygen atom of a neighbouring molecule. Molecules of water are thus held together by hydrogen bonds, which accounts for the unusually high boiling point of water considering its low molecular3 weight. Hydrogen bonds hold protein molecules in shape by linking up various sections. When proteins are heated, these bonds collapse4 and the protein is physically5 altered, even though its chemical composition remains6 unchanged. When an egg is heated the white part rapidly gels, indicating a change in the shape of the protein. The process is not reversible.. so an egg cannot be uncooked.

    Hydroxyapatite - one of the apatites which is the main salt of bone and teeth.

    Hydroxyl ion- a negatively charged ion of hydrogen and oxygen written as OH-.

    Hyperplasia - an increase in the size of an organ due to an increase in the numbers of cells. The developing embryo7 increases in size due to cell division. The cells of some tissues retain the ability to divide throughout life, like the epithelium and connective tissues but muscle and nerve cells lose their ability to divide soon after birth. When hyperplasia is uncontrolled it produces a tumour8 which may be benign9 if it is well contained, not destructive and does not spread. But it may be malignant10, destroys normal tissue, and spread all over the body.

    Hypertrophy - an increase in the size of an organ due to an increase in the size of each cell. Muscles increase in size due to hypertrophy.

    Hypoplasia - reduced formation of a tissue during development. Enamel11 hypoplasia may be recognised as pits and depressions in the enamel and may be cause by fluorosis.

    Hypotonic - a comparison between two solutions, indicating that one has a lower osmotic pressure, or is less salty than the other.


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1 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。
2 molecules 187c25e49d45ad10b2f266c1fa7a8d49     
分子( molecule的名词复数 )
参考例句:
  • The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
  • Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里,大分子裂变为小分子。
3 molecular mE9xh     
adj.分子的;克分子的
参考例句:
  • The research will provide direct insight into molecular mechanisms.这项研究将使人能够直接地了解分子的机理。
  • For the pressure to become zero, molecular bombardment must cease.当压强趋近于零时,分子的碰撞就停止了。
4 collapse aWvyE     
vi.累倒;昏倒;倒塌;塌陷
参考例句:
  • The country's economy is on the verge of collapse.国家的经济已到了崩溃的边缘。
  • The engineer made a complete diagnosis of the bridge's collapse.工程师对桥的倒塌做了一次彻底的调查分析。
5 physically iNix5     
adj.物质上,体格上,身体上,按自然规律
参考例句:
  • He was out of sorts physically,as well as disordered mentally.他浑身不舒服,心绪也很乱。
  • Every time I think about it I feel physically sick.一想起那件事我就感到极恶心。
6 remains 1kMzTy     
n.剩余物,残留物;遗体,遗迹
参考例句:
  • He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
  • The remains of the meal were fed to the dog.残羹剩饭喂狗了。
7 embryo upAxt     
n.胚胎,萌芽的事物
参考例句:
  • They are engaging in an embryo research.他们正在进行一项胚胎研究。
  • The project was barely in embryo.该计划只是个雏形。
8 tumour tumour     
n.(tumor)(肿)瘤,肿块
参考例句:
  • The surgeons operated on her for a tumour.外科医生为她施行了肿瘤切除手术。
  • The tumour constricts the nerves.肿瘤压迫神经。
9 benign 2t2zw     
adj.善良的,慈祥的;良性的,无危险的
参考例句:
  • The benign weather brought North America a bumper crop.温和的气候给北美带来大丰收。
  • Martha is a benign old lady.玛莎是个仁慈的老妇人。
10 malignant Z89zY     
adj.恶性的,致命的;恶意的,恶毒的
参考例句:
  • Alexander got a malignant slander.亚历山大受到恶意的诽谤。
  • He started to his feet with a malignant glance at Winston.他爬了起来,不高兴地看了温斯顿一眼。
11 enamel jZ4zF     
n.珐琅,搪瓷,瓷釉;(牙齿的)珐琅质
参考例句:
  • I chipped the enamel on my front tooth when I fell over.我跌倒时门牙的珐琅质碰碎了。
  • He collected coloured enamel bowls from Yugoslavia.他藏有来自南斯拉夫的彩色搪瓷碗。