医学英语Unit4TextA

1、61 Unit 4 The Circulatory System What people want is not knowledge, but certainty. The art of medicine consists in amusing the patient while nature cures the disease.Unit 4The Circulatory SystemPart A TerminologyStems /Affixes Meaning Examplesangl(o)- vesselangiogram心血管造影术aort(o)-aortaaortic stenosi

2、s主动脉狭窄arter(o)-arteryarteriosclerosis 动脉硬化ather(o)-fatty substanceatheroma 动脉粥样化atri(o)-heart chamberatrioventricular房室的cardi(o)-heartcardiomegaly心肥大coron(o)-heartcoronary artery 冠状动脉hem(o)-blood hemoglobin血红蛋白hemat(o)-bloodhematopericardium心包积血pericardi(o)-pericardiumpericardiocentesis心包穿刺phleb(o)-

3、veinphlebitis静脉炎rrhythm(o)-rhythmarrhythmia心律不齐sphygm(o)-pulsesphygmomanometer血压计steth(o)- cheststethoscope听诊器thromb(o)-clotthrombolysis血栓溶解valvul(o)-valvevalvuloplasty瓣膜成形术vas(o)-vesselvasoconstriction血管收缩vascul(o)-vessel vascular脉管的ven(o)-veinvenous静脉的ventricul(o)-lower heart chamberventriculotmy

4、心室切开术cor(o)-circle or crowncoronary 冠状的ischi(o)-deficiencyischemia局部缺血brady- slowbradycardia心动过缓tachy-fasttachycardia心动过速electr(o)- electricity electrocardiogram心电图-ectomysurgical removal thymectomy 胸腺切除术-graphinstrument to record cardiopneumograph心肺运动描记器-graphy process of recordingcardioangiography

5、心血管造影术-ostomy creating a new or ventriculoatriosto脑室心房造口术an artificial opening -plastysurgical repaircardioplasty 贲门成形术-(r)rhage bleedinghemorrhage 出血-tomyincisioncardiotomy心切开术ExercisesI Give the meaning for the following affixes or stems and provide one example for each.Stems /Affixes Meaning Exam

6、plesangl(o)- arter(o)- cardi(o)- pericardi(o)- rrhythm(o)- thromb(o)- ventricul(o)- brady- hem(o)- II Choose the definition from Column B that best matches the stem or affix in Column A.Column A Column B1. aort(o)-A. vein2. atri(o)-B. vessel3. phleb(o)-C. aorta4. valvul(o)-D. pulse 5. vascul(o)-E. h

7、eart chamber6. ischi(o)-F. slow 7. -ectomyG.creating a new or an artificial opening 8. brady- H. valve9. sphygm(o)-I. surgical removal10. -ostomy J. deficiencyIII Translate the following words and phrases into English.1. 主动脉狭窄 2. 动脉粥样化 3. 瓣膜成形术 4. 静脉炎 5. 局部缺血 6. 心动过速 7. 出血 8. 心切开术 9. 心血管造影术 10. 血栓溶解

8、 Part B Text AWarm-upGroup discussion What do you think is the most dangerous condition related to the circulatory system? The Circulatory SystemThe complex nature of the human body demands an efficient circulatory system in orderto sustain life. The trillions of cells which comprise the human body

9、demand this efficiency in order to maintain the functions of the multitudes of systems within the human body, which represents an ingenious division of labor. The majority of the bodys cells is immobile, and therefore can not retrieve the basics of their existence independently. This means a well or

10、ganized and efficient circulatory system is responsible for deliver life sustaining oxygen and nutrients to the cells which are incapable of fending for themselves. Components of the systemThe heart, blood, and blood vessels are the three structural elements that make up the circulatory system. The

11、heart is the engine of the circulatory system and divided into four chambers: the right atrium, the right ventricle, the left atrium, and the left ventricle. The walls of these chambers are made of a special muscle called myocardium, which contracts continuously and rhythmically to pump blood. The p

12、umping action of the heart occurs in two stages for each heart beat: diastole, when the heart is at rest; and systole, when the heart contracts to pump deoxygenated blood toward the lungs and oxygenated blood to the body. During each heartbeat, typically about 60 to 90 ml of blood are pumped out of

13、the heart. If the heart stops pumping, death usually occurs within four to five minutes.Blood consists of three types of cells: oxygen-bearing red blood cells, disease-fighting white blood cells, and blood-clotting platelets, all of which are carried through blood vessels in a liquid called plasma.

14、Plasma is yellowish and consists of water, salts, proteins, vitamins, minerals, hormones, dissolved gases, and fats.Three types of blood vessels form a complex network of tubes throughout the body. Arteries carry blood away from the heart, and veins carry it toward the heart. Capillaries are the tin

15、y links between the arteries and the veins where oxygen and nutrients diffuse to body tissues. The inner layer of blood vessels is lined with endothelial cells that create a smooth passage for the transit of blood. This inner layer is surrounded by connective tissue and smooth muscle that enable the

16、 blood vessel to expand or contract. Blood vessels expand during exercise to meet the increased demand for blood and to cool the body. Blood vessels contract after an injury to reduce bleeding and also to conserve body heat.Arteries have thicker walls than veins to withstand the pressure of blood be

17、ing pumped from the heart. Blood in the veins is at a lower pressure, so veins have one-way valves to prevent blood from flowing backwards away from the heart. Capillaries, the smallest of blood vessels, are only visible by microscopeten capillaries lying side by side are barely as thick as a human

18、hair. If all the arteries, veins, and capillaries in the human body were placed end to end, the total length would equal more than 100,000 kmthey could stretch around the earth nearly two and a half times.The arteries, veins, and capillaries are divided into two systems of circulation: systemic and

19、pulmonary. The systemic circulation carries oxygenated blood from the heart to all the tissues in the body except the lungs and returns deoxygenated blood carrying waste products, such as carbon dioxide, back to the heart. The pulmonary circulation carries this spent blood from the heart to the lung

20、s. In the lungs, the blood releases its carbon dioxide and absorbs oxygen. The oxygenated blood then returns to the heart before transferring to the systemic circulation.Functions of the systemThe circulatory system is not a stand alone system, and it requires the assistance of systems such as the r

21、espiratory, urinary, endocrine, digestive, and integumentary systems in order to maintain its proper function and give the body the life sustenance it requires to live. While the circulatory system has numerous functions, the various capabilities and functions of this intense system can be segregate

22、d into two basic responsibilities. Transportation of the substances necessary to maintain cellular metabolism is one of two main functions of the circulatory system. In conjunction with the respiratory system, red blood cells by the name of erythrocytes are responsible for the transportation of oxyg

23、en which is systematically delivered to the cells waiting throughout the body. The human body takes a breath, which enters the lungs. In the lungs, the oxygen molecules attach themselves to hemoglobin molecules, which reside within the erythrocytes, and then make their way via transport by these cel

24、ls to cells in need of oxygen. Once the cells have used the oxygen which has been delivered, the carbon dioxide that they have produced are then transported back to the lungs and expelled in exhaled air. The circulatory systemJugular vein LungsSuperior Vena cava Carbon dioxide Pulmonary arteryInferi

25、or Vena cava LiverRenal veinIliac veinHepaticPortal veinCarbon dioxide Head and armsCarotid artrryOxygenPulmonary veinAortaHeartMesenteric arteriesDigestive tractKidneysIlica arteryOxygenThe blood and lymph vessels work in conjunction with the digestive system in order for the circulatory system to

26、perform the delivery of nutrition. When food is eaten it is broken down by the digestive system and the nutrients are absorbed through the wall of the intestines, which is then picked up by the blood vessels and carried off to the cells requiring the nutrition with a pit stop through the liver for n

27、utrient absorption and toxic cleansing. The wastes associated with excess waters, ions, plasma, and metabolic waste produced by the cells, are then filtered through capillaries which belong to the kidneys. From there wastes enter the kidney tubes and are excreted in urine. The circulatory system is

28、also responsible for the transportation of hormones through the blood stream. This contributes to the regulatory process of maintaining health of the endocrine system. The second basic function associated with the circulatory system involves protection. It effectively protects against both injury an

29、d disease through clotting, white blood cells, and the process of phagocytosis. White blood cells called leukocytes fight off disease and foreign material in the body. The body becomes feverish in this action as it works harder to produce a greater number of leukocytes. The bodys natural ability to

30、clot prevents excessive bleeding when blood vessels are harmed or damaged. Excessive damage may cause bleeding faster than the body can create clotting agents, but in most cases the clotting agents cease bleeding for long periods of time. Tissue fluid, also known as interstitial fluid, comes from fl

31、uid derived from the plasma and becomes protective liquid for tissues that are not surrounded by blood. A small percentage of this fluid is returned through the capillaries and is likely to enter the lymphatic system via the connective tissues around the blood vessels. Fluid within the lymphatic sys

32、tem, which is known as lymph, is then discharged back into the venous blood. Strategically placed lymph nodes are responsible for the cleansing of the lymph before it is returned for another use. This is the bodys natural form of recycling and the entire circulatory system is based on this notion of

33、 natural recycling. (1133 words)circulatory / 5sE:kjuleitEri /a. of or relating to the circulatory system 循环系统的nutrient / 5nju:triEnt / n. a source of nourishment, especially a nourishing ingredient in food营养成分chamber / 5tFeimbE / n. an enclosed space in the body of an organism; a cavity 腔atrium / 5

34、B:triEm / n. one of the two spaces in the top of your heart that push blood into the ventricle 心房ventricle / 5ventrikl / n. one of the two spaces in the bottom of your heart through which blood pumps out to your body 心室myocardium / 7maiEu5kB:diEm / n. the muscular tissue of the heart 心肌diastole /dai

35、5AstEli / n. the passive rhythmical expansion or dilation of the cavities of the heart 心脏舒张systole / 5sistEli / n. the contraction of the heart 心脏收缩deoxygenate / di:5CksidVineit / v. to remove oxygen from 去氧,脱氧oxygenate / 5CksidVineit / v. to impregnate, combine, or supply with oxygen 氧化platelet / 5

36、pleitlit / n. a minute colorless anucleate disklike body of mammalian blood 血小板plasma / 5plAzmE / n. the yellowish liquid part of blood that contains the blood cells 血浆hormone / 5hC:mEun / n. a chemical substance produced by your body that influences its growth, development, and condition 荷尔蒙，激素arte

37、ry / 5B:tEri / n. any of a branching system of muscular, elastic tubes that carry blood away from the heart to the cells, tissues, and organs of the body 动脉vein / vein / n. any of a branching system of membranous tubes that carry blood to the heart 静脉capillary / kE5pilEri / n. any of the smallest bl

38、ood vessels connecting arterioles with venules and forming networks throughout the body 毛细血管diffuse / di5fju:z / v. to break up and distribute 扩散endothelial /7endEu5Wi:liEl / a. of, relating to, or produced from endothelium 内皮的valve / vAlv / n. a bodily structure that closes temporarily a passage or

39、 orifice or permits movement of fluid in one direction only 瓣pulmonary / 5pQlmEnEri / a. of, relating to, or affecting the lungs 肺部的carbon dioxide / 5kB:bEn dai5Cksaid / a heavy colorless gas CO2 二氧化碳spent / spent / a. already used, and now empty or useless 用过的urinary / 5juErinEri /a. of or relating

40、 to urine, its production, function, or excretion 泌尿的endocrine / 5endEukrain / a. of, relating to, affecting, or resembling an endocrine gland or secretion 内分泌的 integumentary / in7teju5mentEri / a. an enveloping layer of an organism or one of its parts 外皮的metabolism / me5tAbElizEm / n. the complex o

41、f physical and chemical processes occurring within a living cell or organism 新陈代谢erythrocyte / i5riWrEusait/ n. red blood cell 红细胞hemoglobin / 7hi:mEu5lEubin / n. an iron-containing respiratory pigment of vertebrate red blood cells 血红蛋白lymph / limf / n. a usually clear coagulable fluid that passes f

42、rom intercellular spaces of body tissue into the lymphatic vessels 淋巴腺，淋巴pit stop / pit stCp / n. a place where a brief stop is made 中途休息点ion / 5aiEn / n. an atom or a group of atoms that has acquired a net electric charge by gaining or losing one or more electrons 离子excrete / eks5kri:t / v. to sepa

43、rate and discharge (waste matter) from the blood, tissues, or organs 分泌urine / 5juErin / n. waste material that is secreted by the kidney 尿clot / klCt / n. a thick, viscous, or coagulated mass or lump, as of blood 凝块phagocytosis /fAE7sai5tEusis / n. the engulfing and usually the destruction of particulate matter by phagocytes