1. There are… pictures in the book.
2. Are there… new students in your group?
3. There are… old houses in our street.
4. Are there… English text books on the desks? – Yes, there are…
5. Are there… maps on the walls? – No, there aren't…
6. Are there… pens on the desk? – Yes, there…
7. Are there… sweets in your bag? – Yes, there are…
8. Have you got… English books at home? – Yes, I have…
9. There are… beautiful pictures in the magazine.
10. I have. nice gloves.
11. There are.ink in my pen.
12. Is there… paper on your table?
13. I have got… exercise-books. Give me please.
14. It is. winter. There are. leaves on the trees.
15. There are. schools in this street.
16. Are the. pictures in your book?
17. There are. flowers here in winter.
18. I can see… children in the yard. They are playing.
19. Are there… new buildings your street?
20. There are. people in the park because it is cold.
Answer the questions.
1. Where does air move from?
2. What does pressure gradient need?
3. Does alveolar pressure become less than atmospheric pressure?
4. Between what does the pressure gradient drive the air into the airway?
5. Via what does the air travel?
6. What may bulk flow be?
7. What does the bulk flow depend on?
8. What does velocity represent?
9. What may the flow be at high velocities?
10. What is the pressure difference needed for?
Make the sentences of your own using the new words (10 sentences).
Make your own sentences using SOME, ANY, NO, EVERY (10 sentences).
Find one word, which is a little bit different in meaning from others (найдите одно слово, которое немного отличается от других по смыслу):
1) a) organism; b) salt; c) body;
2) a) health; b) rest; c) cold;
3) a) brick; b) blood; c) liquid;
4) a) hair; b) head; c) foot;
5) a) lamp; b) organ; c) tissue.
ЛЕКЦИЯ № 27. Mechanics of breathing
Muscles of respiration: inspiration is always an active process. The following muscles are involved: The diaphragm is the most important muscle of inspiration. It is convex at rest, and flattens during contraction, thus elongating the thoracic cavity. Contraction of the external in-tercostals lifts the rib cage upward and outward, expanding the thoracic cavity. These muscles are more important for deep inhalations. Accessory muscles of inspiration, including the scalene (elevate the first two ribs) and sternocleidomastoid (elevate the sternum) muscles, are not active during quiet breath ing, but become more important in exercise. Expiration is normally a passive process. The lung and chest wall are elastic and naturally return to their resting positions after being actively expanded during inspiration. Expiratory muscles are used during exercise, forced expiration and cer tain disease states. Abdominal muscles (rectus abdominis, internal and exter nal obliques, and transversus abdominis) increase intra-abdominal pressure, which pushes the diaphragm up, forc ing air out of the lungs. The internal intercostal muscles pull the ribs downward and inward, decreasing the thoracic volume. Elastic properties of the lungs: the lungs collapse if force is not applied to expand them. Elastin in the alveolar walls aids the passive deflation of the lungs. Collagen within the pulmonary in-terstitium resists further expansion at high lung volumes. Compliance is defined as the change in volume per unit change in pressure (AV/AP). In vivo, compliance is measured by esophageal balloon pres sure vs. lung volume at many points during inspiration and expiration. Each measurement is made after the pressure and volume have equilibrated and so this is called static compli ance. The compliance is the slope of the pressure-volume curve. Several observations can be made from the pressure-volumecurve.
Note that the pressure-volume relationship is different with deflation than with inflation of air (hysteresis). The compliance of the lungs is greater (the lungs are more distensible) in the middle volume and pressure ranges.
At high volumes and expanding pressures, the compliance is lower (the lungs are stiffer). Even when the lung has no expanding pressure, some air remains in the lungs. When saline is used to fill the lung, compliance is much greater (small pressure changes bring about large changes in volume). With saline inflation, there is little difference in the pressure-volume relationship with inflation or defla tion. This indicates that the differences seen between infla tion and deflation of air must be due to surface forces in the air-liquid interface of the alveoli.
Causes of decreased compliance: pulmonary fibrosis, pulmonary venous congestion and edema, deficiency of surfactant. Causes of increased compliance: emphysema, age.
New words
muscles – мускулы, мышцы
respiration – дыхание
inspiration – вдох
always – всегда
process – процесс
following – следующий
to be involved – быть вовлеченным
diaphragm – диафрагма
the most – наиболее
important – важный
inspiration – вдохновение
convex – выпуклый
rest – отдых
to flattens – сглаживаться
contraction – сокращение
elongating – удлинение
the thoracic cavity – грудная впадина
the thoracic – грудная клетка
the rib cage -грудное ребро
upward – вверх
outward – наружу
expanding – расширение
volume – объем
compliance – согласие
some – некоторые
to remain – остаться
saline – солончак
to fill – заполняться
Сравните следующие предложения.
