Материал: Лекции по медицине
Заполните пропуски, где необходимо.
1.My friend's … flat is very comfortable.
2.There are ... three rooms in ... flat: ... living-room, ... study and
…bedroom.
3. ... living-room is not very large. 4. ... walls in ... living-room are blue.
5.There are … pictures on … walls.
6.There is … table in ... middle of … room with some chairs around it.
7.To … left of ... door there is ... sofa.
8.Near ... sofa there are ... two large armchairs.
9.They are very … comfortable.
10.There is … piano in my friend's liv ing-room.
11.… piano is to ... right of .
12.… doors of ... bedrooms and ... study are small.
13.When my grandfather was ... young man, he studied ... physics.
14.Do you speak ... Spanish?
15.My uncle is ... great specialist in ... biology.
16.Japanese is more difficult than ... French.
17.We listened to … very interesting lecture.
18.My father speaks ... English and ... French, but he does not speak ... German.
19.We had ... lesson of ... mathematics yesterday.
20.We wrote … test in ... mathematics.
Answer the questions.
1.What component of blood is plasma?
2.What components does the plasma have?
3.Where do large blood proteins remain?
4.Do large blood proteins equilibrate with the interstitial fluid?
5.What colour is serum?
6.Where is serum separated from?
7.What com position does the serum have?
8.What do lymphatic vessels consist of?
9.How do lymphatics serve?
10.How is developed the smooth muscle in large lymphatic ducts?
Make the sentences of your own using the new words (10 sentences). Find the definite and indefinite articles in the text.
ЛЕКЦИЯ № 17. Hematopoietic tissue
Hematopoietic tissue is composed of reticular fibers and cells, blood vessels, and sinusoids (thin-walled blood channels). Myeloid, or blood cell-forming tissue, is found in the bone marrow and provides the stem cells that develop into erythrocytes, granulocytes, agranulocytes, and platelets. Red marrow is characterized by active hematopoiesis; yellow bone marrow is inactive and contains mostly fat cells. In the human adult, hematopoiesis takes place in the mar row of the flat bones of the skull, ribs and sternum, the vertebral column, the pelvis, and the proximal ends of some long bones. Erythropoiesis is the process of RBC formation. Bone marrow stem cells (colony-forming units, CFUs) differentiate into proerythroblasts under the influence of the glycoprotein erythropoietin, which is produced by the kidney.
Proerythroblast is a large basophilic cell containing a large spherical euchromatic nucleus with prominent nucleoli.
Basophilic erythroblast is a strongly basophilic cell with nucleus that comprises approximately 75% of its mass. Numerous cytoplasmic polyribosomes, condensed chromatin, no visible nucleoli, and continued hemoglobin synthesis characteristics of this cell.
Polychromatophilic erythroblast is the last cell in this line undergoes mitotic divisions. Its nucleus comprises approximately 50% of its mass and contains condensed chromatin which appears in a «checkerboard» pattern. The polychnsia of the cytoplasm is due to the increased quantity of acidophilic hemoglobin combined with the basophilia of cytoplasmic polyribosomes.
Normoblast (orthochromatophilic erythroblast) is a cell with a small heterochromatic nucleus that comprises approximately 25% of its mass. It contains acidophilic cytoplasm because the large amount of hemoglobin and degenerating organelles. The pyknotic nucleus, which is no longer capable of division, is extruded from the cell.
Reticulocyte (polychromatophilic erythrocyte) is an immature acidophilic denucleated RBC, which still contains some ribosomes and mitochondria involved in the synthesis of a small quantity of hemoglobin. Approximately 1% of the circulating RBCs are reticulocytes.
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Erythrocyte is the mature acidophilic and denucleated RBC. Erythrocytes remain in the circulation approximately 120 days and are then recycled by the spleen, liver, and bone marrow.
Granulopoiesis is the process of granulocyte formation. Bone marrow stem cells differentiate into all three types of granulocytes.
Myeloblast is a cell that has a large spherical nucleus containing delicate euchromatin and several nucleoli. It has a basophilic cytoplasm and no granules. Myeloblasts divide differentiate to form smaller promyelocytes.
Promyelocyte is a cell that contains a large spherical indented nucleus with coarse condensed chromatin. The cytoplasm is basophilic and contains peripheral azurophilic granules.
Myelocyte is the last cell in this series capable of division. The nucleus becomes increasingly heterochromatic with subsequent divisions. Specific granules arise from the Golgi apparatus, resulting in neutrophilic, eosinophilic, and basophilic myelocytes.
Metamyelocyte is a cell whose indented nucleus exhibits lobe formation that is characteristic of the neutrophil, eosinophil, or basophil. The cytoplasm contains azurophilic granules and increasing numbers of specific granules. This cell does not divide. Granulocytes are the definitive cells that enter the blood. Neutrophilic granulocytes exhibit an intermediate stage called the band neutrophil. This is the first cell of this series to appear in the peripheral blood.
It has a nucleus shaped like a curved rod or band.
Bands normally constitute 0,5—2% of peripheral WBCs; they subsequently mature into definitive neutrophils.
Agranulopoiesis is the process of lymphocyte and monocyte for mation. Lymphocytes develop from bone marrow stem cells (lymphoblasts). Cells develop in bone marrow and seed the secondary lymphoid organs (e. g., tonsils, lymph nodes, spleen). Stem cells for T cells come from bone marrow, develop in the thymus and, subsequently, seed the secondary lym phoid organs.
Promonocytes differentiate from bone marrow stem cells (monoblasts) and multiply to give rise to monocytes.
Monocytes spend only a short period of time in the marrow before being released into the bloodstream.
Monocytes are transported in the blood but are also found in connective tissues, body cavities and organs.
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Outside the blood vessel wall, they are transformed into macrophages of the mononuclear phagocyte system.
Thrombopoiesis, or the formation of platelets, occurs in the red bone marrow.
Megakaryoblast is a large basophilic cell that contains a U-shaped or ovoid nucleus with prominent nucleoli. It is the last cell that undergoes mitosis.
Megakaryocytes are the largest of bone marrow cells, with diameters of 50 mm or greater. They undergo 4—5 nuclear divi sions without concomitant cytoplasmic division. As a result, the megakaryocyte is a cell with polylobulated, polyploid nucleus and abundant granules in its cytoplasm. As megakaryocyte maturation proceeds, «curtains» of platelet demarcation vesicles form in the cytoplasm. These vesicles coalesce, become tubular, and eventually form platelet demarcation membranes. These membranes fuse to give rise to the membranes of the platelets.
A single megakaryocyte can shed (i. e., produce) up to 3,500 platelets.
New words
reticular — сетчатый sinusoids — синусоиды granulocytes — гранулоциты
agranulocytes — агранулоциты active — активный
yellow — желтый glycoprotein — гликопротеин erythropoietin — эритропоэтин large — большой
amount — количество hemoglobin — гемоглобин degenerating — вырождение capable — способный division — разделение spherical — сферический indented — зазубренный condensed — сжатый chromatin — хроматин
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Запомните следующие застывшие словосочетания.
to play _ chess to play the piano to play _ football to play the guitar out of _ doors
Запомните, что перед обращением артикль опускается. Е. g. What are you doing, _ girls?
Заполните пропуски, где необходимо.
1.Do you play ... piano?
2.There is ... big black piano in our living-room.
3.It is at ... wall to ... left of … door opposite ... sideboard.
4.My mother likes to play … piano.
5.She often plays ... piano in ... evening.
6.…boys like to play ... football.
7.What do you do in ... evening? — I often play ... chess with my grandfather.
8.Where are ... children? — Oh, they are out of ... doors. ... weather is fine today.
9.They are playing ... badminton in ... yard.
10.What ... games does your sister like to play?
11.She likes to play ... tennis.
12.Do you like to play ... guitar?
13.What ... colour is your guitar?
14.When we want to write ... letter, we take ... piece of ... paper and
... pen.
15.We first write our ... ad dress and ... date in ... right-hand corner.
16.Then on ... left-hand side we write ... greeting.
17.We must not forget to leave ... margin on ... left-hand side of ...
page.
18.On ... envelope we write ... name and address of … person who will receive it.
19.We stick ... stamp on … top of right-hand corner.
20.We posted ... letter.
Answer the questions.
1.What is hematopoietic tissue composed of?
2.Where is myeloid found?
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