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reflux – рефлюкс

inflammation – воспаление

longitudinal – продольный

flaps – створки

iliac – подвздошный

hepatic – печеночный

26. Heart

Intrapulmonary bronchi: the primary bronchi give rise to three main branches in the right lung and two branches in the left lung, each of which supply a pulmonary lobe. These lobar bronchi divide repeatedly to give rise to bronchioles.

Mucosa consists of the typical respiratory epithelium.

Submucosa consists of elastic tissue with fewer mixed glands than seen in the trachea.

Anastomosing cartilage plates replace the C-shaped rings found in the trachea and extra pulmonary portions of the pri mary bronchi.

Bronchioles do not possess cartilage, glands, or lymphatic nodules; however, they contain the highest proportion of smooth r muscle in the bronchial tree. Bronchioles branch up to 12 times to supply lobules in the lung.

Bronchioles are lined by ciliated, simple, columnar epithelium with nonciliated bronchiolar cells. The musculature of the bronchi and bronchioles con tracts following stimulation by parasympathetic fibers (vagus nerve) and relaxes in response to sympathetic fibers. Terminal bronchioles consist of low-ciliated epithelium with bronchiolar cells.

The costal surface is a large convex area related to the inner surface of the ribs.

The mediastinal surface is a concave medial surface, contains the root, or hilus, of the lung.

The diaphragmatic surface (base) is related to the convex sur face of the diaphragm. The apex (cupola) protrudes into the root of the neck.

The hilus is the point of attachment for the root of the lung. It contains the bronchi, pulmonary and bronchial vessels, lym phatics, and nerves. Lobes and fissures ventricular con traction (systole). Semilunar valves (aortic and pulmonic) prevent reflux of blood back into the ventricles during ventricular relaxation (diastole). Impulse conducting system of the heart consists of specialized cardiac myocytes that are characterized by auto-maticity and rhythmicity (i. e., they are independent of nervous stimulation and possess the ability to initiate heart beats). These specialized cells are located in the sino-atrial (SA) node (pacemaker), intern-odal tracts, atrioven-tricular (AV) node, AV bundle (of His), left and right bundle branches, and numerous smaller branches to the left and right ventricular walls. Impulse conduct ing myocytes are in electrical contact with each other and with normal contractile myocytes via communicating (gap) junctions. Specialized wide-diameter impulse conducting cells (Purkinje myocytes), with greatly reduced myofilament components, are well-adapted to increase conduction velocity. They rapidly deliver the wave of depolarization to ventricular myocytes.

New words

heart – сердце

muscular – мышечный

cardiac – сердечный

to pump – качать

endocardium – эндокардиум

innermost – самый внутренний

conducting system – проведение системы

subendocardial – внутрисердечный

impulse – импульс

fibrosi – фиброзные кольца

27. Lungs

Intrapulmonary bronchi: the primary bronchi give rise to three main branches in the right lung and two branches in the left lung, each of which supply a pulmonary lobe. These lobar bronchi divide repeatedly to give rise to bronchioles.

Mucosa consists of the typical respiratory epithelium.

Submucosa consists of elastic tissue with fewer mixed glands than seen in the trachea.

Anastomosing cartilage plates replace the C-shaped rings found in the trachea and extra pulmonary portions of the pri тагу bronchi.

Bronchioles do not possess cartilage, glands, or lymphatic nodules; however, they contain the highest proportion of smooth r muscle in the bronchial tree. Bronchioles branch up to 12 times to supply lobules in the lung.

Bronchioles are lined by ciliated, simple, columnar epithelium with nonciliated bronchiolar cells. The musculature of the bronchi and bronchioles con tracts following stimulation by parasympathetic fibers (vagus nerve) and relaxes in response to sympathetic fibers. Terminal bronchioles consist of low-ciliated epithelium with bronchiolar cells.

The costal surface is a large convex area related to the inner surface of the ribs.

The mediastinal surface is a concave medial surface, contains the root, or hilus, of the lung.

The diaphragmatic surface (base) is related to the convex sur face of the diaphragm. The apex (cupola) protrudes into the root of the neck.

The hilus is the point of attachment for the root of the lung. It contains the bronchi, pulmonary and bronchial vessels, lym phatics, and nerves. Lobes and fissures.

The right lung has three lobes: superior, middle and inferior.

The left lung has upper and lower lobes.

Bronchopulmonary segments of the lung are supplied by the segmental (tertiary) bronchus, artery, and vein. There are 10 on the right and 8 on the left.

Arterial supply: Right and left pulmonary arteries arise from the pulmonary trunk. The pulmonary arteries deliver deoxygenated blood to the lungs from the right side of the heart.

Bronchial arteries supply the bronchi and nonrespiratory por tions of the lung. They are usually branches of the thoracic aorta.

Venous drainage. There are four pulmonary veins: superior right and left and inferior right and left. Pulmonary veins carry oxygenated blood to the left atrium of the heart.

The bronchial veins drain to the azygos system.

Bronchomediastinal lymph trunks drain to the right lymphatic duct and the thoracic duct.

Innervation of Lungs: Anterior and posterior pulmonary plexuses are formed by vagal (parasympathetic) and sympathetic fibers. Parasympathetic stimulation has a bronchoconstrictive effect. Sympathetic stimulation has a bronchodilator effect.

New words

lungs – легкие

intrapulmonary bronchi – внутрилегочные бронхи

the primary bronchi – первичные бронхи

lobar bronchi – долевые бронхи

submucosa – подслизистая оболочка

28. Respiratory system

The respiratory system is structurally and functionally adapt ed for the efficient transfer of gases between the ambient air and the bloodstream as well as between the bloodstream and the tissues. The major functional components of the res piratory system are: the airways, alveoli, and bloodvessels of the lungs; the tissues of the chest wall and diaphragm; the systemic blood vessels; red blood cells and plasma; and respi ratory control neurons in the brainstem and their sensory and motor connections. LUNG FUNCTION: provision of 02 for tissue metabolism occurs via four mechanisms. Ventilation – the transport of air from the environment to the gas exchange surface in the alveoli. 02 diffusion from the alveolar air space across the alveolar-capillary membranes to the blood.

Transport of 02 by the blood to the tissues: 02 diffusion from the blood to the tissues.

Removal of C02 produced by tissue metabolism occurs via four mechanisms. C02 diffusion from the tissues to the blood.

Transport by the blood to the pulmonary capillary-alveolar membrane.

C02 diffusion across the capillary-alveolar membrane to the air spaces of the alveoli. Ventilation – the transport of alveolar gas to the air. Functional components: Conducting airways (conducting zone; anatomical dead space).

These airways are concerned only with the transport of gas, not with gas exchange with the blood.

They are thick-walled, branching, cylindrical structures with ciliated epithelial cells, goblet cells, smooth muscle cells. Clara cells, mucous glands, and (sometimes) cartilage.

Alveoli and alveolar septa (respiratory zone; lung parenchyma).

These are the sites of gas exchange.

Cell types include: Type I and II epithelial cells, alveolar macrophages.

The blood-gas barrier (pulmonary capillary-alveolar membrane) is ideal for gas exchange because it is very thin (‹ 0,5 mm) and has a very large surface area (50 – 100 m2). It consists of alveolar epithelium, basement membrane interstitium, and capillary endothelium.

New words

respiratory – дыхательный

air – воздух

bloodstream – кровоток

airways – воздушные пути

alveoli – альвеолы

blood vessels – кровеносные сосуды

lungs – легкие

chest – грудь

diaphragm – диафрагма

the systemic blood vessels – системные кровеносные сосуды

red blood cells – красные кровяные клетки

plasma – плазма

respi ratory control neurons – дыхательные нейроны контроля

brainstem – ствол мозга

sensory – сенсорный

motor connections – моторные связи

ventilation – вентиляция

transport – транспортировка

environment exchange – окружающая среда

surface – поверхность

29. Lung volumes and capacities

Lung volumes – there are four lung volumes, which when added together, equal the maximal volume of the lungs. Tidal volume is the volume of one inspired or expected normal breath (average human = 0,5 L per breath). Inspiratory reserve volume is the volume of air that can be inspired in excess of the tidal volume. Expiratory reserve volume is the extra an that can be expired after a normal tidal expiration.

Residual volume is the volume of gas that re lungs after maximal expiration (average human = 1,2 L).

Total lung capacity is the volume of gas that can be con tained within the maximally inflated lungs (average human = 6 L).

Vital capacity is the maximal volume that can be expelled after maximal inspiration (average human = 4,8 L).

Functional residual capacity is the volume remaining in the lungs at the end of a normal tidal expiration (average luman = 2,2 L).

Inspiratory capacity is the volume that can be taken into the lungs after maximal inspiration following expiration of a normal breath. Helium dilution techniques are used to determine residual volume, FRC and TLC. A forced vital capacity is obtained when a subject inspires maximally and then exhales as forcefully and as completely as possible. The forced expiratory volume (FEV1) is the volume of air exhaled in the first second. Typically, the FEV1 is approximate 80 % of the FVC.

GAS LAWS AS APPLIED TO RESPIRATORY PHYSIOLOGY: Dalton's Law: In a gas mixture, the pressure exerted by each gas is independent of the pressure exerted by the other gases.

A consequence of this is as follows: partial pressure = total pressure x fractional concentration. This equation can be used to determine the partial pressure of oxygen in the atmosphere. Assuming that the total pressure (or barometric pressure, PB) is atmospheric pressure at sea level (760 mmHg) and the fractional concentration of O2 is 21 %, or 0,21: P02 = 760 mmHg Ч 0,21 = 160 mmHg. As air moves into the airways, the partial pressures of the va-ri ous gases in atmospheric air are reduced because of the addi tion of water vapor (47 mmHg). Henry's Law states that the concentration of a gas dissolved in liquid is proportional to its partial pressure and its solubility coef fi-cient (Ks). Thus, for gas X, [X] = Ks Ч Px

Fick's Law states that the volume of gas that diffuses across a barrier per unit time is given by:

Vgas = Y x D x (P1 – P2)

where A and T are the area and thickness of the barrier, P1 and P2 are the partial pressures of the gas on either side of the barrier and D is the diffusion constant of the gas. D is directly proportional to the solubility of the gas and inversely proportional to the square root of its molecular weight.

New words


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