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专业术语—口腔生理学术语V(英文详解)

时间：2006-07-05 16:00:00

（单词翻译:单击）

 

    Vaccine1 - a planned exposure to an antigen in order that memory B lymphocytes can retain a memory for it. In practice the organism carrying the antigen is either killed or modified so that it does not cause the disease. When encountered again, the antigen is recognised and there will be a rapid production of antibodies. For example smallpox2, polio, measles3. Influenza4 vaccines5 are less effective as new strains of the virus are always occurring which do not have recognisable antigens.

    Vacuole- a sac-like structure within a cell lined by cell membrane6, containing material ingested by phagocytosis.

    Vasoconstriction - a reduction in the diameter of small arteries8 (arterioles) which is caused by constriction7 of the smooth muscle fibres in the wall of the arteriole. Vasoconstriction is an important method of increasing the blood pressure. In local areas of damage it prevents blood loss by haemostasis. Local vasoconstriction can be caused by nerve impulses to the smooth muscle from the sympathetic nervous system, by locally released prostaglandins, serotonin and Epinephrine.

    Vasodilation - an increase reduction in the diameter of small arteries (arterioles) which is caused by relaxation9 of the smooth muscle fibres in the wall of the arteriole. While vasoconstriction prevents blood loss in damaged tissues, vasodilation follows in order to allow the blood flow to slow down and clotting10 factors and leucotrines to seep11 into the damaged tissue. Local vasodilation can be caused by nerve impulses to the smooth muscle from the parasympathetic nervous system, and by locally released bradykinins.

    Visco-elastic - a property of a material which combines elasticity12 and viscosity13. The suspension of a car and the periodontal ligament of the tooth are examples of visco-elastic support. Elasticity refers to the return of a material to its original shape after being stretched or compressed. Viscosity is the resistance of a fluid to flowing fast.

    Viscous14 - a liquid which has a high viscosity, or resistance to flow.


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1 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。
2 smallpox 9iNzJw     
n.天花
参考例句：
  • In 1742 he suffered a fatal attack of smallpox.1742年，他染上了致命的天花。
  • Were you vaccinated against smallpox as a child?你小时候打过天花疫苗吗？
3 measles Bw8y9     
n.麻疹，风疹，包虫病，痧子
参考例句：
  • The doctor is quite definite about Tom having measles.医生十分肯定汤姆得了麻疹。
  • The doctor told her to watch out for symptoms of measles.医生叫她注意麻疹出现的症状。
4 influenza J4NyD     
n.流行性感冒，流感
参考例句：
  • They took steps to prevent the spread of influenza.他们采取措施
  • Influenza is an infectious disease.流感是一种传染病。
5 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。
6 membrane H7ez8     
n.薄膜，膜皮，羊皮纸
参考例句：
  • A vibrating membrane in the ear helps to convey sounds to the brain.耳膜的振动帮助声音传送到大脑。
  • A plastic membrane serves as selective diffusion barrier.一层塑料薄膜起着选择性渗透屏障的作用。
7 constriction 4276b5a2f7f62e30ccb7591923343bd2     
压缩； 紧压的感觉； 束紧； 压缩物
参考例句：
  • She feels a constriction in the chest. 她胸部有压迫感。
  • If you strain to run fast, you start coughing and feel a constriction in the chest. 还是别跑紧了，一咬牙就咳嗽，心口窝辣蒿蒿的！ 来自汉英文学 - 骆驼祥子
8 arteries 821b60db0d5e4edc87fdf5fc263ba3f5     
n.动脉( artery的名词复数 )；干线，要道
参考例句：
  • Even grafting new blood vessels in place of the diseased coronary arteries has been tried. 甚至移植新血管代替不健康的冠状动脉的方法都已经试过。 来自《简明英汉词典》
  • This is the place where the three main arteries of West London traffic met. 这就是伦敦西部三条主要交通干线的交汇处。 来自《简明英汉词典》
9 relaxation MVmxj     
n.松弛，放松；休息；消遣；娱乐
参考例句：
  • The minister has consistently opposed any relaxation in the law.部长一向反对法律上的任何放宽。
  • She listens to classical music for relaxation.她听古典音乐放松。
10 clotting 9eca3747f25ae6f0d50d00d5b71d5d7d     
v.凝固( clot的现在分词 )；烧结
参考例句：
  • The study was also based only on the one anti-clotting drug. 所用抗血栓药物也仅限于一种。 来自互联网
  • A plasma protein that is converted into thrombin during blood clotting. 凝血原酶一种血浆蛋白质，在血液凝聚时转化成凝血''。'酵'。''''。'素'。''。 来自互联网
11 seep rDSzK     
v.渗出，渗漏；n.渗漏，小泉，水（油）坑
参考例句：
  • My anger began to seep away.我的怒火开始消下去了。
  • If meteoric water does not evaporate or run overland,it may seep directly into the ground.如果雨水不从陆地蒸发和流走的话，就可能直接渗入地下。
12 elasticity 8jlzp     
n.弹性，伸缩力
参考例句：
  • The skin eventually loses its elasticity.皮肤最终会失去弹性。
  • Every sort of spring has a definite elasticity.每一种弹簧都有一定的弹性。
13 viscosity ehPwf     
n.粘度，粘性
参考例句：
  • The viscosity shows a rather pronounced variation with temperature.温度对粘度的影响十分明显。
  • The reciprocal of viscosity is known as fluidity.粘度的反意就是流动性。
14 viscous KH3yL     
adj.粘滞的，粘性的
参考例句：
  • Gases are much less viscous than liquids.气体的粘滞性大大小于液体。
  • The mud is too viscous.You must have all the agitators run.泥浆太稠，你们得让所有的搅拌机都开着。