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Reticulocyte Production Index
The reticulocyte production index (RPI), also called a corrected reticulocyte count (CRC), is a calculated value used in the diagnosis of anemia. This calculation is necessary because the raw reticulocyte count is misleading in anemic patients. The problem arises because the reticulocyte count is not really a ''count'' but rather a ''percentage'': it reports the number of reticulocytes as a percentage of the number of red blood cells. In anemia, the patient's red blood cells are depleted, creating an erroneously elevated reticulocyte count. Physiology Reticulocytes are newly produced red blood cells. They are slightly larger than totally mature red blood cells, and have some residual ribosomal RNA. The presence of RNA allows a visible blue stain to bind or, in the case of fluorescent dye, result in a different brightness. This allows them to be detected and counted as a distinct population.Adamson JW, Longo DL. Anemia and polycythemia. ''in:'' Braunwald E, et al. ''Harriso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anemia
Anemia or anaemia (British English) is a blood disorder in which the blood has a reduced ability to carry oxygen due to a lower than normal number of red blood cells, or a reduction in the amount of hemoglobin. When anemia comes on slowly, the symptoms are often vague, such as tiredness, weakness, shortness of breath, headaches, and a reduced ability to exercise. When anemia is acute, symptoms may include confusion, feeling like one is going to pass out, loss of consciousness, and increased thirst. Anemia must be significant before a person becomes noticeably pale. Symptoms of anemia depend on how quickly hemoglobin decreases. Additional symptoms may occur depending on the underlying cause. Preoperative anemia can increase the risk of needing a blood transfusion following surgery. Anemia can be temporary or long term and can range from mild to severe. Anemia can be caused by blood loss, decreased red blood cell production, and increased red blood cell breakdown. Causes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reticulocyte
Reticulocytes are immature red blood cells (RBCs). In the process of erythropoiesis (red blood cell formation), reticulocytes develop and mature in the bone marrow and then circulate for about a day in the blood stream before developing into mature red blood cells. Like mature red blood cells, in mammals, reticulocytes do not have a cell nucleus. They are called reticulocytes because of a reticular (mesh-like) network of ribosomal RNA that becomes visible under a microscope with certain stains such as new methylene blue and Romanowsky stain. Clinical significance To accurately measure reticulocyte counts, automated counters use a combination of laser excitation, detectors and a fluorescent dye that marks RNA and DNA (such as titan yellow or polymethine). Reticulocytes appear slightly bluer than other red cells when looked at with the normal Romanowsky stain. Reticulocytes are also relatively large, a characteristic that is described by the mean corpuscular volume. The n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reference Ranges For Blood Tests
Reference ranges (reference intervals) for blood tests are sets of values used by a health professional to interpret a set of medical test results from blood samples. Reference ranges for blood tests are studied within the field of clinical chemistry (also known as "clinical biochemistry", "chemical pathology" or "pure blood chemistry"), the area of pathology that is generally concerned with analysis of bodily fluids. Blood test results should always be interpreted using the reference range provided by the laboratory that performed the test. Interpretation A reference range is usually defined as the set of values 95 percent of the normal population falls within (that is, 95% prediction interval). It is determined by collecting data from vast numbers of laboratory tests. Plasma or whole blood In this article, all values (except the ones listed below) denote blood plasma concentration, which is approximately 60–100% larger than the actual blood concentration if the amount insid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polychromatic Erythrocyte
Polychrome is the "practice of decorating architectural elements, sculpture, etc., in a variety of colors." The term is used to refer to certain styles of architecture, pottery or sculpture in multiple colors. Ancient Egypt Colossal statue of Tutankhamun Paris 2019 A.jpg, Polychrome quartzite colossal statue of Tutankhamun, 1355-1315 BC Nofretete Neues Museum.jpg, Polychrome limestone and plaster ''Bust of Nefertiti'', 1352–1336 BC Composite Papyrus Capital MET 10.177.2 EGDP018080.jpg, Polychrome sandstone Composite papyrus capital, 380–343 BC Medinet Habu 2016-03-23g.jpg, Polychrome winged sun on a cavetto from the Medinet Habu temple complex, unknown date Classical world Some very early polychrome pottery has been excavated on Minoan Crete such as at the Bronze Age site of Phaistos. In ancient Greece sculptures were painted in strong colors. The paint was frequently limited to parts depicting clothing, hair, and so on, with the skin left in the natural co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erythrocyte
Red blood cells (RBCs), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells), haematids, erythroid cells or erythrocytes (from Greek ''erythros'' for "red" and ''kytos'' for "hollow vessel", with ''-cyte'' translated as "cell" in modern usage), are the most common type of blood cell and the vertebrate's principal means of delivering oxygen (O2) to the body tissues—via blood flow through the circulatory system. RBCs take up oxygen in the lungs, or in fish the gills, and release it into tissues while squeezing through the body's capillaries. The cytoplasm of a red blood cell is rich in hemoglobin, an iron-containing biomolecule that can bind oxygen and is responsible for the red color of the cells and the blood. Each human red blood cell contains approximately 270 million hemoglobin molecules. The cell membrane is composed of proteins and lipids, and this structure provides properties essential for p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reticulocyte
Reticulocytes are immature red blood cells (RBCs). In the process of erythropoiesis (red blood cell formation), reticulocytes develop and mature in the bone marrow and then circulate for about a day in the blood stream before developing into mature red blood cells. Like mature red blood cells, in mammals, reticulocytes do not have a cell nucleus. They are called reticulocytes because of a reticular (mesh-like) network of ribosomal RNA that becomes visible under a microscope with certain stains such as new methylene blue and Romanowsky stain. Clinical significance To accurately measure reticulocyte counts, automated counters use a combination of laser excitation, detectors and a fluorescent dye that marks RNA and DNA (such as titan yellow or polymethine). Reticulocytes appear slightly bluer than other red cells when looked at with the normal Romanowsky stain. Reticulocytes are also relatively large, a characteristic that is described by the mean corpuscular volume. The n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bone Marrow
Bone marrow is a semi-solid biological tissue, tissue found within the Spongy bone, spongy (also known as cancellous) portions of bones. In birds and mammals, bone marrow is the primary site of new blood cell production (or haematopoiesis). It is composed of Blood cell, hematopoietic cells, marrow adipose tissue, and supportive stromal cells. In adult humans, bone marrow is primarily located in the Rib cage, ribs, vertebrae, sternum, and Pelvis, bones of the pelvis. Bone marrow comprises approximately 5% of total body mass in healthy adult humans, such that a man weighing 73 kg (161 lbs) will have around 3.7 kg (8 lbs) of bone marrow. Human marrow produces approximately 500 billion blood cells per day, which join the Circulatory system, systemic circulation via permeable vasculature sinusoids within the medullary cavity. All types of hematopoietic cells, including both Myeloid tissue, myeloid and Lymphocyte, lymphoid lineages, are created in bone marrow; howev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemorrhage
Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vagina or anus, or through a puncture in the skin. Hypovolemia is a massive decrease in blood volume, and death by excessive loss of blood is referred to as exsanguination. Typically, a healthy person can endure a loss of 10–15% of the total blood volume without serious medical difficulties (by comparison, blood donation typically takes 8–10% of the donor's blood volume). The stopping or controlling of bleeding is called hemostasis and is an important part of both first aid and surgery. Types * Upper head ** Intracranial hemorrhage – bleeding in the skull. ** Cerebral hemorrhage – a type of intracranial hemorrhage, bleeding within the brain tissue itself. ** Intracerebral hemorrhage – bleeding in the brain caused by the rup ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erythropoietin
Erythropoietin (; EPO), also known as erythropoetin, haematopoietin, or haemopoietin, is a glycoprotein cytokine secreted mainly by the kidneys in response to cellular hypoxia; it stimulates red blood cell production ( erythropoiesis) in the bone marrow. Low levels of EPO (around 10 mU/mL) are constantly secreted in sufficient quantities to compensate for normal red blood cell turnover. Common causes of cellular hypoxia resulting in elevated levels of EPO (up to 10 000 mU/mL) include any anemia, and hypoxemia due to chronic lung disease. Erythropoietin is produced by interstitial fibroblasts in the kidney in close association with the peritubular capillary and proximal convoluted tubule. It is also produced in perisinusoidal cells in the liver. Liver production predominates in the fetal and perinatal period; renal production predominates in adulthood. It is homologous with thrombopoietin. Exogenous erythropoietin, recombinant human erythropoietin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reticulocytopenia
Reticulocytopenia is the medical term for an abnormal decrease of reticulocytes in the body. Reticulocytes are new, immature red blood cells. Causes Reticulocytopenia is usually a result of viral parvovirus B19 infection, which invades and destroys red blood cell precursors and halts the red cell production. If infection occurs in individuals with sickle cell anemia,"Sickle Cell Disease - Basic Principles and Clinical Practice" Edited by Stephen H. Embury, Robert P. Hebbel, Narla Mohandas and Martin Steinberg. Copyright 1996 by Lippincott-Raven. Section IV p352. spherocytosis, or beta thalassemia, it will lead to incorporation of two anemia-induced mechanisms: decreased red cell production and hemolysis. The result is a rapid and severe anemia (aplastic crisis) which may require blood transfusion. Diagnosis See also * Erythropoiesis – process of creating red blood cells * Hemolytic anemia – reduced number of red blood cells due to destruction of the cells after they wer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
