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Erythrocytapheresis
Erythrocytapheresis is an apheresis procedure by which erythrocytes (red blood cells) are separated from whole blood. It is an extracorporeal blood separation method whereby whole blood is extracted from a donor or patient, the red blood cells are separated, and the remaining blood is returned to circulation. Method Overview For the separation of erythrocytes, whole blood is passed through an apparatus that isolates the red blood cells from the remaining components. In erythrocytapheresis, centrifugation is the most commonly used red blood cell fractionation method. This is because the hematocrit, or the percentage of blood volume taken up by red blood cells, is present in the highest percentage of all blood cell components in the solid portion of blood. Therefore, since erythrocytes have the highest specific weight in comparison to other solids in blood, they can easily be separated using centrifugation. Whole blood is spun down in a spinning bowl centrifuge and the botto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apheresis
Apheresis ( ἀφαίρεσις (''aphairesis'', "a taking away")) is a medical technology in which the blood of a person is passed through an apparatus that separates one particular constituent and returns the remainder to the circulation. It is thus an extracorporeal therapy. One of the uses of apheresis is for collecting hematopoietic stem cells. Method Depending on the substance that is being removed, different processes are employed in apheresis. If separation by density is required, centrifugation is the most common method. Other methods involve absorption onto beads coated with an absorbent material and filtration. The centrifugation method can be divided into two basic categories: Continuous flow centrifugation Continuous flow centrifugation (CFC) historically required two venipunctures , as "continuous" means the blood is collected, spun, and returned simultaneously. Newer systems can operate with a single venipuncture by collecting blood in a vessel an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erythrocytes
Red blood cells (RBCs), referred to as erythrocytes (, with -''cyte'' translated as 'cell' in modern usage) in academia and medical publishing, also known as red cells, erythroid cells, and rarely haematids, are the most common type of blood cell and the vertebrate's principal means of delivering oxygen () to the body tissue (biology), tissues—via blood flow through the circulatory system. Erythrocytes take up oxygen in the lungs, or in fish the gills, and release it into tissues while squeezing through the body's capillary, capillaries. The cytoplasm of a red blood cell is rich in hemoglobin (Hb), 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 physiological Cell (biology), cell function such as erythrocyte deformabil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centrifugation
Centrifugation is a mechanical process which involves the use of the centrifugal force to separate particles from a solution according to their size, shape, density, medium viscosity and rotor speed. The denser components of the mixture migrate away from the axis of the centrifuge, while the less dense components of the mixture migrate towards the axis. Chemists and biologists may increase the effective gravitational force of the test tube so that the precipitate (pellet) will travel quickly and fully to the bottom of the tube. The remaining liquid that lies above the precipitate is called a supernatant or supernate. There is a correlation between the size and density of a particle and the rate that the particle separates from a heterogeneous mixture, when the only force applied is that of gravity. The larger the size and the larger the density of the particles, the faster they separate from the mixture. By applying a larger effective gravitational force to the mixture, like ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hematocrit
The hematocrit () (Ht or HCT), also known by several other names, is the volume percentage (vol%) of red blood cells (RBCs) in blood, measured as part of a blood test. The measurement depends on the number and size of red blood cells. It is normally 40.7–50.3% for males and 36.1–44.3% for females. It is a part of a person's complete blood count results, along with hemoglobin concentration, white blood cell count and platelet count. Because the purpose of red blood cells is to transfer oxygen from the lungs to body tissues, a blood sample's hematocrit—the red blood cell volume percentage—can become a point of reference of its capability of delivering oxygen. Hematocrit levels that are too high or too low can indicate a blood disorder, dehydration, or other medical conditions. An abnormally low hematocrit may suggest anemia, a decrease in the total amount of red blood cells, while an abnormally high hematocrit is called polycythemia. Both are potentially life-threatening d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrophoresis
Electrophoresis is the motion of charged dispersed particles or dissolved charged molecules relative to a fluid under the influence of a spatially uniform electric field. As a rule, these are zwitterions with a positive or negative net charge. Electrophoresis is used in laboratories to separate macromolecules based on their charges. The technique normally applies a negative charge called cathode so anionic protein molecules move towards a positive charge called anode. Therefore, electrophoresis of positively charged particles or molecules (cations) is sometimes called cataphoresis, while electrophoresis of negatively charged particles or molecules (anions) is sometimes called anaphoresis. Electrophoresis is the basis for analytical techniques used in biochemistry and molecular biology to separate particles, molecules, or ions by size, charge, or binding affinity, either freely or through a supportive medium using a one-directional flow of electrical charge. It is use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
