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Используя текст «LIVER», опишите устно на английском языке печень.

16. Ответьте на вопросы.

1. What is the liver?

2. Where is the liver located?

3. How many principal lobes does the liver have?

4. What is the surface of the liver covered with?

5. What is the microscopic structure of the liver?

6. Where is blood brought to the liver from?

7. What are the functions of the liver?

8. What is a pear-shaped hollow sac attached to the under surface of the liver?

9. Where does the gallbladder end?

10. What is the function of the gallbladder?

Выполните письменный перевод текста “Kidneys” на русский язык, используя словарь. Составьте список ключевых терминов к каждой части текста. Составьте предложения с ключевыми словами.

Kidneys

Kidneys are a pair of glands situated close to the spine in the upper part of the abdomen. They are on a level with the last dorsal and upper two lumbar vertebrae, and each is, to a great extent, covered behind by the twelfth rib of its own side. They are kept in this position by a quantity of fat and loose connective tissue, in which they are embedded, by the large vessels which supply them with blood, by the peritoneal membrane stretched over their front surface, and largely by the pressure of the other abdominal organs against them.

Structure. In size each isabout 4 inches long, 2.5 inches wide, 1.5 inches thick, and weighs over 4 ounces. The size, however, varies a good deal. The left kidney is slightly longer and narrower, and lies a trifle higher in the abdomen than the right.

The kidney in adult human beings presents a smooth exterior, though in early life, as in many animals, it is divided up into distinct lobes, corresponding to the pyramids found in the interior. Enveloping it is a tough fibrous coat, which, in the healthy state, is bound to the kidney only by loose fibrous tissues and by a few blood vessels that pass between it and the kidney.

The outer margin of the kidney is convex, the inner is concave, presenting a deep depression, known as the hilus, where the vessels enter its substance. At the hilus the renal vein lies in front of the renal artery, the former joining the inferior vena cava, and the latter springing from the aorta almost at a right angle. Here, too, the ureter, which conveys urine down to the bladder, is attached. The ureter is spread out into an expanded, funnel-like end, known as the pelvis, to which the capsule of the kidney is firmly attached and which further divides into little funnels known as the calices.

On splitting open a kidney, one finds it to consist of two distinct parts: a layer on the surface, about 1/6 inch thick, known as the cortex, and a part towards the hilum, known as the medulla. The latter consists of pyramids, arranged side by side, with their base on the cortex and their apex projecting into the calices of the pelvis. The apex of each pyramid, of which there are about 15-20 in all, is studded with minute holes, which are the openings of the microscopic uriniferous tubes.

Each pyramid is in effect taken together with the portion of the cortex lying along its base, an independent little kidney. About a score of small tubes open on the surface of each pyramid and these, if traced up into its substance, divide again and again so as to form bundles of tubes, known as medullary rays, passing up towards the cortex. If one of these be traced still farther back, it is found, after a very tortuous course, to end in a small rounded body, the Malpighian corpuscle or glomerulus.

If the blood vessels now be traced through the kidney, their course is found to be as follows. The renal artery splits up into branches, which form arches at the line of junction of cortex and medulla, and from these again spring vessels that run up through the cortex, giving off small branches in every direction.

Each of these at last ends in a little tuft of capillaries enclosed in a capsule (Bowman's), that forms the end of the uriniferous tube above described, and capillaries with a capsule are known as a glomerulus. The blood, after circulating in the glomerulus, emerges by a small vessel, which again splits up into capillaries on the walls of the uriniferous tubes. From these it is collected finally into the renal veins and by them leaves the kidney.

By means of the double circulation, first through the glomerulus and then around the tube a large amount of fluid is removed from the blood in the glomerulus, and then the concentrated blood passes on to the uriniferous tube for removal of parts of its solid contents. Other straight arteries come off from the arches above mentioned and supply the medulla direct, the blood from these passing through another set of capillaries and also finally into the renal veins.

Though the circulation just described is confined entirely to the kidney, it has certain small connections both by arteries and veins which pass through the capsule and join the lumbar vessels communicating direct with the aorta.

Function. The chief function of the kidneys is to separate fluid and certain solids from the blood. The glomeruli filter from the blood the non-protein portion of the plasma. As this filtrate passes through the convoluted tubules varying parts of it are reabsorbed. It is estimated that in 24 hours the total human glomeruli will filter between 15 and 200 liters, 99 per cent of which is reabsorbed by the tubules. The constituents of the filtrate may be grouped according to the extent to which they are reabsorbed by the tubules: I) substances actively reabsorbed, such as amino acids, glucose, potassium, calcium, magnesium and chlorine; 2) substances passing through the tubular epithelium by a simple process of diffusion when their concentration in the filtrate exceeds that in the plasma, such as urea, uric acid, phosphate; 3) substances not returned to the blood from the tubular fluid - e. g., creatine.

When the kidneys are diseased and the number of glomeruli and tubules decreased in consequence, this alternating action is not so readily carried out, and therefore the work of the diseased kidney becomes much embarrassed. When the blood vessels of the kidney are partially closed by disease (arteriosclerosis), the general blood pressure rises with the object of forcing more blood through the kidneys; and, in consequence, marked changes are produced upon the heart in this type of renal disease. When the kidneys fail to act, these solid waste substances accumulate in the blood. The general poisoning resulting from failure of renal function produces the clinical condition known as uraemia.

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