Infection

BLOOD

TEXT B

If an infection is too virulent, or the body resistance too weak, the white cells are unable to contain the infection and it can spread throughout the body. Before the discovery of antibiotics, such spread was usually fatal. If the balance between infection and body resistance us equal, a condition of stalemate may supervene, often leading to a persistent state of chronic infection.

During the battle between invading bacteria and white cells in the inflamed area, many casualties occur. These dead white cells and bacteria form the creamy liquid known as pus. A localized collection of pus is called an abscess. Abscess of the skin are called boils. Sometimes pus formation spreads diffusely instead of forming an abscess. This is called cellulites.

In the absence of infection, pus formation does not occur and any damage done by the causal irritant is repaired.

Following inflammation the damage is repaired by white cells which rebuild the area by filling the breach with a temporary repair tissue called granulation tissue. This consists of rapidly growing white cells and new capillaries which form fibrous scaffolding in which damaged parts are removed and reconstruction take place. But repair cannot take place in the presence of pus.

ACTIVE VOCABULARY

Read and learn the following words

1. contain содержать

2. plasma плазма

3. microscopical микроскопический

4. element элемент

5. erythrocyte эритроцит

6. leucocyte лейкоцит

7. thrombocyte тромбоцит

8. bone marrow костный мозг

9. transport транспортировать, переносить

10. convert преобразовывать,превращать

11. carry переносить

12. arrive прибывать

13. expel вытеснять, выводить

14. catabolism катаболизм

15. hemoglobin (haemoglobin) гемоглобин

16. agranulocyte агранулоцит

17. cytoplasm цитоплазма

18. granulocyte гранулоцит

19. eosinophil иозофил

20. basophil базофил

21. neutrophil нейтрофил

22. node узел

23. spleen селезенка

24. lymphocyte лимфоцит

25. monocyte моноцит

26. platelet тромбоцит

27. tiny крошечный

28. blood clotting свертываемость крови

29. occur происходить, случаться

30. remain оставаться

31. coagulation коагуляция

32. complete заканчивать

Blood contains a fluid called plasma plus microscopical cellular elements: erythrocytes, leucocytes, and thrombocytes.

Erythrocytes are red blood cells of which 4.5 – 5 million are found in each cubic millimeter. These cells are made in the bone marrow and are important in transporting oxygen from the lungs through the blood stream to the cells all over the body. The oxygen is then used up by body cells in the process of converting food to energy (catabolism). Hemoglobin, containing iron, is an important protein in erythrocytes, which helps in carrying the oxygen as it travels through the blood stream. Erythrocytes also carry away carbon dioxide (CO2), a waste product of catabolism of food in cells, from the body cells to the lungs. On arriving there it is expelled in the process of breathing.

Leucocytes are white blood cells from 4.000 to 10.000 per cubic millimeter exiting in several types: granulocytes and agranulocytes, which are also subdivided into different types.

Granulocytes are cells with granules in their cytoplasm formed in the bone marrow. There are three types of granulocytes: eosinophils, basophils, neutrophils.

Agranulocytes are produced in lymph nodes and spleen. There are two types of agranulocytes: lymphocytes and monocytes.

Thrombocytes or platelets are tiny cells formed in the bone marrow. They are necessary for blood clotting. Their number is 400.000 per cubic millimeter. The plasma is the fluid portion before clotting has occurred. The serum is the fluid portion of blood remaining after the coagulation process is completed.

The body contains about five liters of blood kept at a constant temperature of 37*C. Blood consists of three different types of cell floating in a liquid called plasma. The blood cells are known as red cells, white cells and platelets. Red cells and platelets are unique among body cells in having no nucleus. Blood cells are so small that one cubic

millimeter of blood (the size of a pin head) contains about five million red cells, 7.000 white cells and 250.000 platelets.

The red blood cells contain a pigment called hemoglobin, which gives the blood its red color. The main function of red cells is to carry oxygen to the body cells.

For its journey from the lungs to the body cells, oxygen combines with hemoglobin of the red cells. It is then released from the hemoglobin when the body cells are reached. Some people do not have enough hemoglobin in their red cells and are consequently short of oxygen. This condition is called anemia and such people tire easily, become breathless on exertion and have a pale complexion. They need special care during general anesthesia.

The white blood cells defend the body against disease. They do this by attacking germs and repairing damage.

The function of platelets is to stop bleeding. They do this in two ways: by blocking the cut blood vessels; and by producing substances, which help the blood to clot.

EXERCISES

EXERCISE 1 Найдите в тексте эквиваленты следующих слов и словосочетаний:

1. микроскопические клеточные элементы

2. в каждом кубическом миллиметре

3. через кровоток

4. по всему организму

5. процесс превращения пищи в энергию

6. выводить

7. продукт отхода

8. выталкивать, выбрасывать

9. несколько видов

10. лимфатические узлы

11. крошечные клетки

12. свертываемость крови

13. завершаться

EXERCISE 2. Процитируйте предложения со следующими словами и словосочетаниями из текста:

1. to call

2. to be found

3. bone marrow

4. to be used

5. to convert

6. iron

7. to be expelled

8. spleen

9. a fluid portion

10. coagulation process

EXERCISE 3 Переведите следующие словосочетания:

1. the habit of smocking

2. the way of producing it

3. the hope of seeing you

4. the chance of getting the prize

5. the method of transporting

6. the necessity of knowing

7. the importance of carrying away waste products

8. the time of arriving

9. the fact of existing

EXERCISE4. Составьте предложения, используя следующие модели, переведите на русский язык:

MODEL: You can learn English.(to work hard)

You can learn English by working hard.

1. You can improve your health (to walk in the evening, to have a proper diet, to follow your doctor’s advice).

2. You will help me (to take part in the conference, to deliver a lecture on Monday, to organize a seminar).

3. You can keep up your English (to read books in the original, to learn grammar, to work with a tape- recorder).

EXERCISE 5. Ответьте на следующие вопросы:

1. What does blood contain?

2. How many erythrocytes can be found in each cubic millimeter/

3. Where are these cells made?

4. What is their function?

5. What role does hemoglobin play?

6. What are the types of leucocytes?

7. 7.Where are agranulocytes produced?

8. 8.What types of granulocytes do you know?

9. 9.What organ forms thrombocytes?

10. How many platelets are there in one cubic millimeter?

11. 11.What is the difference between the plasma and serum?

EXERCISE 6. Вставьте артикли, где это необходимо:

1. Blood contains … fluid called plasma and cellular elements.

2. Erythrocytes (red blood cells) are important in … gas exchange taking place in … lungs.

3. Leucocytes (white blood cells) are subdivided into … different types.

4. Granulocytes are formed in … bone marrow.

5. Agranulocytes are produced in … lymph nodes and … spleen.

6. Platelets are … tiny cells formed in the bone remaining after … coagulation process is the serum.

EXERCISE7. Вставьте предлоги или наречия:

1. Thrombocytes are necessary … blood clotting.

2. The plasma is the fluid portion … clotting has occurred.

3. There are two types … agranulocytes.

4. Granulocytes are cells … granules in their cytoplasm.

5. The number of leucocytes is … 4.000 … 10.000 per cubic millimeter.

6. The oxygen is used … body cells in the process …converting food … energy.

7. Carbon dioxide is expelled … the process … breathing.

8. Erythrocytes transport oxygen … the lungs … the blood stream … the cells of the body.

9. They also carry … a waste product … catabolism.

EXERCISE8. Закончите предложение, используя окончание ing. Слова изправой колонки вам помогут:

1. Do you mind my… to ask you

2. I insist on … to do it now, not tomorrow

3. The lecturer began … to speak on gas exchange in the lungs

4. It’s no use … to try it again

5. He stopped … to do laboratory experiments on blood

6. Most of us dislike the idea of … to be examined

7. We had no difficulty in … to learn the blood formula

8. Please go on … to speak on the topic

9. I can not help … to visit my sister, who is ill

10. The students made much progress to learn this material in Physiology by…

EXERCISE 9. Составьте 10 вопросов к тексту “Blood ”.

EXERCISE 10. Приготовьте пересказ текста “Blood”.

ACTIVE VOCABULARY

Read learn the following words and word combinations:

1. mean означать

2. invasion инвазия, вторжение

3. saliva слюна

4. contaminated зараженный

5. skin cuts порезы

6. abrasion абразия

7. staff персонал

8. defence оборона

9. intact неповрежденный

10. surface поверхность

11. liquid жидкость

12. produce производить

13. poison яд

14. kill убивать

15. tears слезы

16. sweat пот

17. similar подобный, схожий

Infection means invasion of the body by microorganisms, which are harmful. The most common sources of infection in medical practice are direct contact with a patient’s blood and saliva, consequently instruments and equipment used in the treatment become contaminated. If no action were taken infection may enter the body through skin cuts or abrasions or the eyes, it may also be swallowed. Infection from the contamination would be passed on from patient to patient, from patient to staff and from staff to patient. This involvement is called cross – infection.

Even ancient people taught that body’s first of defense against infection was an intact surface, e.g. the outer layer of skin and the protective outer layer of

mucous membrane. If infection had passed it the second line of defense started its action. It was the liquid secretion produced by the protective surfaces. The mucous membrane and the salivary glands had produced saliva, which neutralized some bacterial poisons and could kill some microorganisms. Tears and sweat had a similar effect. The acidity of gastric juice killed many bacteria in food. The third line of defense is discovered now. It is immunity.

And we also know that if these defense mechanisms fail to prevent infection, the last line of defense is a response by the body called inflammation.

EXERCISES

EXERCISE 1. Найдите в тексте эквиваленты следующих слов и словосочетаний:

1. Означать

2. Кровь и слюна пациента

3. Через порезы на коже

4. Глотать

5. Наружный слой слизистой оболочки

6. Продуцируемая защитной поверхностью

7. Яды, вырабатываемые бактериями

8. Желудочный сок

9. Пища

10. Ответная реакция

EXERCISE 2. Процитируйте предложения из текста со следующими словами и словосочетаниями:

1. Direct

2. Abrasion

3. To teach

4. To start

5. To produce

6. To kill

7. To discover

8. Mechanism

9. Effect

EXERCISE 3. Ответьте на следующие вопросы:

1. What are the most common sources of infection?

2. How may infection enter the body?

3. What did ancient people teach?

4. When does the second line of defense start its action?

5. What is it produced by?

6. What can saliva do?

7. What effect do tears and sweat have?

8. When was the third line discovered?

9. What is the last line of defense?

EXERCISE4. Измените предложения в прошедшее совершенное время:

MODEL: They have finished the work (by 5 o’clock yesterday).

They had finished the work by 5 o’clock yesterday.

1. My friend has prepared the report (by last Monday).

2. The students have done the exercises (by the end of the lesson).

3. Mother has cooked supper (by the time I came home).

4. We have not seen our teacher (before the bell rang).

5. Have you done the work (before I called you up)?

6. He has translated the article (by this time yesterday).

7. She has not bought a present for him (when we came to her place).

EXERCISE 5. Составьте 12 вопросов к тексту “Infection”.

EXERCISE 6. Приготовьте пересказ текста “Infection ”.

TEXT B

In order to prevent cross – infection it is essential to kill all the microorganisms on infected instruments. This process is known as sterilization and means the killing of all microorganisms: bacteria, spores, fungi, and viruses. It is carried out immediately after completion of treatment so that all instruments are sterile again before use on the next patient.

Countless number of microorganisms lives on the skin and in the mouth, nose and throat. Normally they do no harm to their host as they living on an external surface and not among delicate internal cells. However, they may become harmful if they are introduced inside the body tissues, or are transferred from one person to another. This can occur when the tissues penetrated by contaminated forceps blade, scalper or syringe needle, and may give rise to harmful reaction. After each patient has left the surgery, it is the nurse`s duty to see that all instruments are properly sterilized before being used again for another patient.

As already mentioned, sterilization means killing not only bacteria and fungi, but all other microorganisms, including viruses and bacterial spores. Any method which kills bacteria and fungi but allows some spores or viruses to survive cannot be sterilization. The term used for this restricted range of action is disinfection.

Дата добавления: 2014-12-16