Blood is a very special juice

These words of The great writer, poet, scientist I. V. Goethe are consonant with the Bible: “Blood is the soul of man“. After all, human life is connected with blood and depends on blood. Blood circulates in blood vessels, it delivers all the necessary cells and tissues (including oxygen, nutrients, hormones, etc.) and, last but not least, takes away all the harmful substances to be excreted from the body. The total amount of blood in an adult male 5-6 l.

Attention! Loss 50% lethal blood loss 30 % threat is only possible loss to 10 % of the blood.

Blood consists of cells that are suspended in a liquid medium-blood plasma (Fig. 23 per cent. insert.) Plasma contains up to 91 % water, 6.5-8 % protein (about 70 g/l). The plasma is formed by solutions of various inorganic salts of sodium, potassium, calcium, etc., many other trace elements and biologically active substances. In the blood are non-nuclear red blood cells – (4,0-5,0)×1012 l-1, leukocytes–(4,0-6,0)×109 l-1, among which are granular or granulocytes, and non-granular, or agranulocytes (monocytes). In the blood there are also blood plates (platelets), the number of which is (180,0—320,0)×109 l-1. In the blood cells of the immune system are constantly present – lymphocytes. Red blood cells (from Greek. erythros-red), or red blood cells, nuclear-free cells, having the form of biconcave discs. The red blood cell is filled with hemoglobin, carrying oxygen and carbon dioxide. The total number of red blood cells of an adult male reaches 25 × 1012, and the total surface area of all red blood cells – about 3800 m2. If you add all the red blood cells in a row, the length of the chain will be 175 000 km, it could encircle the globe more than four times.

In 1900-1901 the Viennese scientist K. Landsteiner discovered blood groups. In 1930, he was awarded the Nobel prize “for the discovery of human blood groups.” K. Landsteiner described four blood groups. He found that when mixing the blood plasma of one person and the red blood cells of another is often their bonding (agglutination). This leads to clogging of small vessels, which can lead to death. The blood serum of group 0 contains group antibodies anti-A and anti-B; in the serum of group A there are only antibodies anti-B, in the serum of group B – antibodies anti-A, and in the serum AB group antibodies are absent. Therefore, in accordance with the formula Landsteiner serum contains only those antibodies (isoagglutinins) that do not agglutinate red blood cells of this group, so if necessary, a person should only transfuse blood of the same group.

In 1940, Landsteiner discovered another blood factor – RH (Rh-factor), which was first discovered in the monkey macaque rhesus. In 85 % of people, red blood cells carry on their surface Rh-antigen is Rh-positive (Rh+), in others it is absent, they are called RH-negative (Rh-). If a person is Rh-transfused blood from a donor with Rh+, then the first within two to four months will produce Rh-antibodies, and if he is transfused again Rh+ blood, then there will be agglutination of Rh+ red blood cells. Landsteiner found a link between Rh and neonatal jaundice. If the Rh-woman is pregnant with Rh + men, the fetus may be Rh+. Then during the first pregnancy in the mother’s body produced Rh-antibodies. During subsequent pregnancy, if this woman carries Rh + fetus, its Rh-antibodies penetrate through the placenta into the fetal blood and cause it to agglutinate red blood cells, which leads to jaundice newborn.

Every man at least once in his life thinks about the problem of fatherhood. Determination of blood groups of parents and the child can dispel doubt.

But … there are sad exceptions. Many years ago I operated on a five-year-old boy for acute appendicitis (I was a very young doctor then). Before the operation in the children’s surgical Department, he was determined blood type-III. The next day, the doctor was approached by an agitated father: “Doctor, this can not be. You made a mistake, Dima can not be group III blood, because my wife and my eldest daughter – the first. My wife and I have a happy marriage, we love each other passionately, I trust her completely!”Re – determination of blood group did not change anything-III! Talking to mom didn’t make any sense. The mother claimed that she had never had another man in her life. Of course, neither I (doctor) nor my husband believed. Tragic outcome. The claim of the husband about divorce was at once satisfied: III group of blood of the boy-irrefutable proof of infidelity of the wife! Irrefutable?.. I forgot about this story, and 10 years later I came across an article by an Indian doctor from Bombay in an English medical journal, in which Dr. Bhend described the result that surprised the medical world: father I has blood type, mother II, child III. No one could give an explanation for this miracle. And only a few decades later a solution was found. Human blood group is determined by two genes: one directly and the other indirectly encodes the enzyme, without which this group can not be realized. But the second factor is the most important. In the case I described, one of the parents, apparently, was group III blood, but the second gene was defective, so not produced an enzyme that would have realized this group, why was the “simulation” group I. This pathology is called “Bombay phenotype”. And although it occurs in no more than 0.8–0.9% of people, it should be remembered. And men in a similar situation should not make a fatal decision.

Leukocytes (from the Greek. leukos-white) – nucleated cells with amoeboid mobility. One microliter of blood of a healthy person contains 4000-8000 leukocytes. If you add up all the human leukocytes in a row, it stretches over a distance of about 525 km from leukocytes distinguish between granulocytes and agranulocytes. Granulocytes – granular white blood cells in which the staining in the cytoplasm of visible granules. Such cells can be classified based on the color in which the granules are colored, respectively, as neutrophils, eosinophils and basophils.

Neutrophils are characterized by lobular venom and the presence in the cytoplasm of small neutrophils and azurophilic granules. Neutrophils are able to absorb and destroy bacteria, carrying out phagocytosis. Phagocytizing decay products and microorganisms, neutrophilic granulocytes die, and thus released lysosomal enzymes destroy the surrounding tissue, contributing to the formation of an ulcer. The composition of pus usually includes destroyed neutrophilic granulocytes and decay products. The number of neutrophilic granulocytes increases sharply in acute inflammatory and infectious diseases. Neutrophil granulocytes make up from 93 to 96 % of all granulocytes (average 4150 in one microliter of blood).

Eosinophils – a kind of white blood cells, characterized by the presence in their cytoplasm of large granules, stained orange-red. Eosinophils are able to absorb foreign particles, they are present in large quantities in the mucous membranes and participate in allergic reactions. Normally, a liter of blood contains (40-400)×106 eosinophils. The number of eosinophils in the blood increases with allergies, worms and other parasites. Basophils-a kind of white blood cells, which are characterized by the presence in the cytoplasm of large granules, stained purple-black. Basophils are able to absorb foreign particles and, in addition, contain histamine and heparin in their composition. Normally, one liter of blood contains (30-150)×106 basophils.

Monocytes – non-granular leukocytes in their cytoplasm and many lysosomes. The function of monocytes is to eliminate foreign particles from the body, such as bacteria and dead tissue (phagocytosis). Normally, one liter of blood contains (0.2–0.8)×10 monocytes. Monocytes are precursors of macrophages.

Macrophage (macrophagocyte). In 1882, I. I. Mechnikov first described phagocytosis. Plunging into the transparent body of the larvae of the starfish thorn rose, he observed that a few hours later the thorn was enveloped in a layer of “mobile cells”. If the splinter was previously smeared with Carmine powder or Indigo paint, then the moved cells were filled with these paints. These cells are very voracious and absorb everything they can capture.” I. I. Mechnikov was awarded the Nobel prize for the discovery of phagocytosis. In the 70’s. XX century formed an idea of the system of mononuclear phagocytes (smf), including a group of cells, United by a common origin (of blood monocytes), structure and function (active phagocytosis). The main functions of macrophages are participation in protective reactions.

Platelets – blood plates, flattened oval nuclear-free fragments of megakaryocytes. Platelets perform several functions, but they are all associated with stopping bleeding. Platelets are involved in protective reactions, and produce platelet growth factor. Normally, a liter of blood contains (150-400)×109 platelets. If you place all human platelets nearby, they will stretch about 2500 km, this is the distance from Moscow to Paris.

Stop bleeding. A healthy person has a bleeding wound of small vessels stops for 1-3 min primary hemostasis (from the Greek. haima-blood, stasis-immobility) associated with vasoconstriction and adhesion of platelets that adhere to the edges of the wound. If the blood vessel wall is damaged, platelets stick to them, biologically active substances are released from platelets, which cause vasoconstriction. With more significant damage, a blood clot forms, which clogs the damaged vessel, and bleeding stops.

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