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Английский язык для медиков: конспект лекций - Беликова Елена - Страница 13


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Posterior intercostal arteries: the first two pairs arise from the superior intercostal artery, a branch of the costocervical trunk of the subcla vian artery.

Nine pairs of intercostal and one pair of subcostal arter ies arise from the thoracic aorta.

Intercostal veins: Anterior branches of the intercostal veins drain to the internal thoracic and musculophrenic veins.

Posterior branches drain to the azygos system of veins.

Lymphatic drainage of intercostal spaces: anterior drainage is to the internal thoracic (parasternal) nodes.

Posterior drainage is to the paraaortic nodes of the poste rior mediastinum.

New words

thoracic – грудной

wall – стенка

below – под

sternum – грудина

clavicle – ключица

xiphisternal – грудинный

true – правдивый

false – фальшивый

groove – углубление

above – над

anteriorly – раньше

intercostal – межреберный

subcostal – подкостный

portion – часть

transversus – поперечный

musculophrenic – мышечный грудобрюшной

paraaortic – парааортальный

mediastinum – средостение

Запомните следующее застывшее словосочетание.

I to watch _ TV

Если перед существительным стоит вопросительное или относительное местоимение, артикль опускается.

E. g. What colour is your cat?

I want to know what _ book you are reading.

Заполните пропуски, где необходимо.

1. My… aunt and my… uncle are… doctors.

2. They work at… hospital.

3. They get up at seven o'clock in… morning.

4. They go to… bed at eleven o'clock.

5. I work in… morning and in. after noon.

6. I don't work in… evening. I sleep at… night.

7. When do you leave… home for… school?

8. I leave… home at… quarter past eight in… morning.

9. What does your mother do after… breakfast?

10. She goes to… work.

11. Is there… sofa in your… living-room?

12. Yes, there is… cosy little… sofa in… living-room.

13. Where is… sofa? – It is in… corner of… room to… left of… door.

14. I like to sit on this… sofa in… front of… TV-set in… evening.

15. There is… nice coffee-table near… window.

16. There are… newspapers on… coffee-table.

17. There is… tea in… glass.

18. When do you watch… TV? – I watch TV in… evening.

19. We have… large colour TV-set in our… room.

20. There is. beautiful vase on… TV-set. There are… flowers in… vase.

Answer the questions.

1. How many thoracic vertebrae are there?

2. What does each rib articulate with?

3. What does the manubrium articulates with?

4. With how many ribs does the body articulates directly?

5. How many pairs of ribs are there?

6. How are termed ribs 1-7?

7. How are termed ribs 8-10?

8. How are classified ribs 11-12?

9. How many pairs of thoracic nerves are there?

10. What does intercostal nerves supply?

Make the sentences of your own using the new words (10 sentences).

Find the definite and indefinite articles in the text.

ЛЕКЦИЯ № 15. Blood

Blood is considered a modified type of connective tissue. Mesoder-mal in origin, it is composed of cells and cell frag ments (erythrocytes, leukocytes, platelets), fibrous proteins (fibrinogen – fibrin during clotting), and an extracellular amorphous ground substance of fluid and proteins (plasma). Blood carries oxygen and nutrients to all cells of the body and waste materials away from cells to the kidney and lungs. It also contains cellular elements of the immune system as well as humoral factors. This chapter will discuss the differ ent elements of blood and the processes by which they are formed.

Formed elements of the blood

The formed elements of the blood include erythrocytes, leukocytes, and platelets.

Erythrocytes, or red blood cells, are important in trans porting oxygen from the lungs to tissues and in returning carbon dioxide to the lungs. Oxygen and carbon dioxide carried in the RBC combine with hemoglobin to form oxyhemoglobin and carbaminohemoglobin, respectively.

Mature erythrocytes are denucleated, biconcave disks with a diameter of 7-8 mm. The biconcave shape results in a 20-30% increase in sur face area compared to a sphere.

Erythrocytes have a very large surface area: volume ratio that allows for efficient gas transfer. Erythrocyte membranes are remarkably pliable, enabling the cells to squeeze through the narrowest capillaries. In sickle cell anemia, this plasticity is lost, and the subsequent clogging of capillaries leads to sickle crisis. The normal concentration of erythrocytes in blood is 3,5-5,5 million/mm3 in women and 4,3– 5,9 million/mm3 in men. Higher counts in men are attributed to the erythrogenic androgens. The packed volume of blood cells per total volume of known as the hematocrit. Normal hematocrit values are 46% for women and 41-53% for men.

When aging RBCs develop subtle changes, macrophages in the bone marrow, spleen, and liver engulf and digest them. The iron is carried by transferring in the blood to certain tissues, where it combines with apoferritin to form ferritin. The heme is catabolized into biliver-din, which is converted to bilirubin. The latter is secreted with bile salts.

Leukocytes, or white blood cells, are primarily with the cellular and humoral defense of the organism foreign materials. Leukocytes are classified as granulocytes (neutrophils, eosinophils, basophils) and agranulocytes (lympmonocytes).

Granulocytes are named according to the staining properties of their specific granules. Neutrophils sare 10-16 mm in diameter.

They have 3-5 nuclear lobes and contain azurophilic granules (ly-sosomes), which contain hydrolytic enzymes for bacterial destruction, in their cytoplasm. Specific granules contain bactericidal enzymes (e. g., lysozyme). Neutrophils are phagocytes that are drawn (chemo-taxis) to bacterial chemoattractants. They are the primary cells involved in the acute inflammatory response and represent 54-62% of leukocytes.

Eosinophils: they have a bilobed nucleus and possess acid granulations in their cytoplasm. These granules contain hydrolytic enzymes and peroxidase, which a discharged into phagocytic vacuoles.

Eosinophils are more numerous in the blood durii asitic infections and allergic diseases; they norma asent onlyi – 3% of leukocytes.

Basophils: they possess large spheroid granules, which are basophi-lic and metachromatic, due to heparin, a glycosaminoglycan. Their granules also contain histamine.

Basophils degranulate in certain immune reaction, releasing hepa-rin and histamine into their surroundings. They also release additional vasoactive amines and slow reacting substance of anaphylaxis (SRS-A) consisting of leukotrienes LTC4, LTD4, and LTE4. They represent less than 1% – of leukocytes.

Agranulocytes are named according to their lack of specific granules. Lymphocytes are generally small cells measuring 7-10 mm in diameter and constitute 25-33% of leukocytes. They con tain circular dark-stained nuclei and scanty clear blue cyto plasm. Circulating lymphocytes enter the blood from the lymphatic tissues. Two principal types of immunocompetent lymphocytes can be identified using im-munologic and bio chemical techniques: T lymphocytes and В lymphocytes.

T cells differentiate in the thymus and then circulate in the peripheral blood, where they are the principal effec tors of cell-mediated immunity. They also function as helper and suppressor cells, by modulating the immune response through their effect on В cells, plasma cells, macrophages, and other T Cells.

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