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Your Key to Good Health. Elaine Hruska
Читать онлайн.Название Your Key to Good Health
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isbn 9780876048498
Автор произведения Elaine Hruska
Жанр Эзотерика
Издательство Ingram
One very important function of the lymphatic system is its ability to carry away from the tissue spaces proteins and large particulate matter, neither of which can be placed directly into the blood capillary. You might think, so what? What’s so fantastic about moving these substances from the fluid between the cells into the bloodstream? However, the removal of proteins from these spaces is an absolutely essential function, for without it we would die within close to twenty-four hours. Take note of this quote from Guyton’s Anatomy and Physiology:
The single most important function of the lymphatics is to return proteins to the circulation when they leak out of the blood capillaries. Some of the pores in the capillaries are so large that small amounts of proteins leak continuously, amounting each day to approximately one-half of the total protein in the circulation. If these proteins were not returned to the circulation, the person’s plasma colloid osmotic pressure [pressure that moves fluid into the capillary] would fall so low and he would lose so much blood volume into the interstitial spaces that he would die within twelve to twenty-four hours. Furthermore, no other means is available by which proteins can return to the circulation except by way of the lymphatics. p. 511
So if it were not for this ongoing removal of proteins, life could no longer continue. The exchange of fluids would be so abnormal that we would cease to exist. As stated in the quote, no other route exists in our bodies except the lymphatics to return these excess proteins to the circulatory system. Hence, no other function of the lymphatic system can even approach this highly important, life-sustaining role.
MAIN PARTS OF THE SYSTEM
Structurally, the lymphatic system is composed of lymph, lymphatic vessels, lymph nodes, Peyer’s patches, and lymphatic organs. (See Fig. 1.) Serving as a defense against infection, the lymphatic system plays an important role in the body’s immunologic response as well as helps to maintain a balance of fluids in the body. A network of lymph nodes clustered in groups and connected by lymphatic vessels make up part of this vast system, which resembles a tree with its main trunk located at the center of the body, its branches reaching out with smaller and smaller twigs, and its foliage covering most of the human body. Or it can be said to resemble an extensive subway system, with its many tubes and tunnels running throughout the body. (See Fig. 2.)
Looking more carefully at each component of the lymphatic system, mentioned above, we have the following descriptions:
Lymph is a clear, watery-appearing fluid, originating in the connective tissue spaces of the body. It is still a mystery, however, exactly how it is formed. The fluid is referred to as lymph once it enters the initial lymph capillaries and is carried through the lymphatic vessels (lymphatics) to lymph nodes, to ducts and trunks, then to the venous system, eventually reaching the heart. Interstitial fluid, the watery substance found in between the cells, is formed by components of blood plasma that have filtered through the blood capillary walls. Yet lymph and interstitial fluid are similar: the former is located within lymphatic vessels and lymphatic tissue, while the latter is found in between the cells.
Lymphatic vessels begin as closed-end structures called lymphatic capillaries. Just as smaller blood capillaries eventually form veins, lymphatic capillaries unite to form larger and larger tubes. In a similar fashion, but in reverse, a large tree trunk divides into smaller branches, then into even smaller twigs. As noted above, these vessels (also called lymphatics) route the lymph fluid on its way to the heart.
Figure 1
Principal components of the lymphatic system
Drawing by Evan Van Auken
At various intervals, like subway stations, the lymph fluid flows through lymph nodes, oval or bean-shaped structures located along the length of the lymphatic vessels. Scattered throughout the body and usually clustered in groups, they act as purification and filtering centers, breaking down and destroying harmful particles in the lymph so that they can be flushed out of the body and eliminated through the lungs, skin, kidneys, and intestines, the body’s main organs of elimination. We usually become aware of them when they become swollen and somewhat achy and painful. There can be from four hundred to seven hundred nodes in the human body, nearly half of them in the abdomen; the others are located in the neck region, armpits (axillae), groin, behind the knees (popliteal area), in the bend of the elbows, and in breast tissue. Flowing in one direction, lymph enters the nodes at one end and exits at another, in the process being cleansed of foreign and harmful substances. As it travels through the nodes, the flow of lymph is usually slowed, allowing time for this cleansing and filtering process to take place. The nodes are also the site of maturation for some lymphocytes, a type of white blood cell important to the body’s defense system.
Peyer’s patches are large specialized collections of lymphoid tissue located in the small intestine, particularly in the ileum. They were named after Johann K. Peyer (1653-1712), a Swiss anatomist, and are mentioned in over sixty readings by Cayce. Bacteria, which enter the body through the mouth, eventually penetrate into the wall of the small intestine, where they multiply in the area of the Peyer’s patches. After a week or two, the bacteria enter the bloodstream. The Cayce readings concur with this function, recognizing this area as the place where poisons can be absorbed into the system. (More about this structure in chapter 5.)
Lastly, we have the lymphatic organs: tonsils, thymus, spleen, liver, appendix, and bone marrow. They, too, help the body fight infection, each in its own unique way.
The tonsils are located at the back of the mouth, at either side of the throat. They assist in trapping and destroying microorganisms and keeping infections away from the lungs. During childhood, around ages six or seven, they are the largest in size but gradually shrink throughout one’s life. They are removed usually in cases where recurrent attacks of tonsillitis (inflammation and swelling of the tonsils) may interfere with the child’s breathing, swallowing, or general health, but—aside from these instances—the operation is usually not necessary and only performed as a last resort.
Figure 2
The lymphatic vessels, larger lymphatic trunks, and lymph nodes
In the long unrecognized thymus, a small gland near the heart, the cells of the immune system learn to differentiate self from non-self. When the immune system starts developing in the fetus, stem cells migrate to the thymus. Here they develop into T lymphocytes, white blood cells which help protect against viral infections as well as detect and destroy some cancer cells. (When these T lymphocytes lose their ability to differentiate self from non-self, autoimmune disease may result.) That it plays a critical part in the body’s defense against infection was not well known until the 1960s. Largest in size at puberty, the gland gradually shrinks and eventually atrophies when the person is much older, its lymphatic tissue replaced by fat, perhaps completing most of its essential work early in childhood. Despite this atrophy, however, some T cells continue to proliferate in the thymus throughout one’s lifetime.
About the size of a fist, the spleen, which is the largest mass of lymphatic tissue in the body, is located in the upper left part of the abdominal cavity, just under the rib cage. Its function is to produce, monitor, store, and destroy blood cells. Its spongelike tissue is of two types: white pulp, which is part of the infection-fighting (immune) system