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dialysis
di·al·y·sis D0196100 (dī-ăl′ĭ-sĭs)n. pl. di·al·y·ses (-sēz′) 1. The separation of smaller molecules from larger molecules or of dissolved substances from colloidal particles in a solution by selective diffusion through a semipermeable membrane.2. Medicine Any of several techniques, especially hemodialysis and peritoneal dialysis, in which filtration through a semipermeable membrane is used to remove metabolic wastes and excess fluid from the blood of people with kidney failure.
[Greek dialusis, separating, dissolution, from dialūein, to break up, dissolve : dia-, apart; see dia- + lūein, to loosen; see leu- in Indo-European roots.]
di′a·lyt′ic (-ə-lĭt′ĭk) adj.di′a·lyt′i·cal·ly adv.dialysis (daɪˈælɪsɪs) n, pl -ses (-ˌsiːz) 1. (Chemistry) the separation of small molecules from large molecules and colloids in a solution by the selective diffusion of the small molecules through a semipermeable membrane2. (Medicine) med See haemodialysis, peritoneal dialysis[C16: from Late Latin: a separation, from Greek dialusis a dissolution, from dialuein to tear apart, dissolve, from luein to loosen] dialytic adj ˌdiaˈlytically advdi•al•y•sis (daɪˈæl ə sɪs)
n., pl. -ses (-ˌsiz) 1. the separation of crystalloids from colloids in a solution by diffusion through a membrane. 2. the process, used in treating kidney disease, by which uric acid and urea are removed from circulating blood by means of a dialyzer. [1580–90; < Late Latin < Greek diálysis a separation, derivative of dialý(ein) to part, separate (dia- dia- + lyein to loosen)] di`a•lyt′ic (-əˈlɪt ɪk) adj. di·al·y·sis (dī-ăl′ĭ-sĭs)1. The separation of the smaller molecules in a solution from the larger molecules by passing the solution through a membrane that does not allow the large molecules through.2. The removal of wastes from the bloodstream by a machine that performs dialysis when the kidneys do not function properly.dialysisthe process whereby colloids and crystalloids separate in solution by diffusion through a membrane. — dialytic, adj.See also: BiologydialysisA method of compensating for poorly functioning kidneys by using a machine to artificially remove waste products from the blood.Thesaurus| Noun | 1. | dialysis - separation of substances in solution by means of their unequal diffusion through semipermeable membraneschemical analysis, qualitative analysis - the act of decomposing a substance into its constituent elementspheresis, apheresis - a procedure in which blood is drawn and separated into its components by dialysis; some are retained and the rest are returned to the donor by transfusionhaemodialysis, hemodialysis - dialysis of the blood to remove toxic substances or metabolic wastes from the bloodstream; used in the case of kidney failureosmosis - (biology, chemistry) diffusion of molecules through a semipermeable membrane from a place of higher concentration to a place of lower concentration until the concentration on both sides is equal |
Translationsdialysis
dialysis (dīăl`ĭsĭs), in chemistry, transfer of solute (dissolved solids) across a semipermeable membrane. Strictly speaking, dialysis refers only to the transfer of the solute; transfer of the solvent is called osmosisosmosis
, transfer of a liquid solvent through a semipermeable membrane that does not allow dissolved solids (solutes) to pass. Osmosis refers only to transfer of solvent; transfer of solute is called dialysis.
..... Click the link for more information. . Dialysis is frequently used to separate different components of a solution. For example, a solution of starch and sodium chloride in water can be separated by placing the mixture in a vessel on one side of a semipermeable membrane and placing pure water on the other side. The smaller particles of sodium chloride (which dissolve in water to form sodium and chloride ions) will diffuse across the membrane; diffusion of the much larger starch particles (which are not truly in solution but are in colloidal suspension) is hindered and may be completely prevented. By continuously or periodically replacing the solvent with fresh solvent, almost all of the sodium chloride can be removed. The method was originated by Thomas Graham, who termed the substance that remained within the membrane a colloid and the substance that diffused a crystalloid. An extension of the method makes possible the separation of mixed colloids by the use of a semipermeable membrane (usually synthetic) of known selectivity, i.e., one that will permit the diffusion of one colloid and hinder the diffusion of others. Mixed macromolecules, such as proteins, may be similarly separated. By the use of graded semipermeable membranes chosen to allow successively smaller molecules to pass, mixtures can be separated into components of graded ranges of molecular weight. Hemodialysis Artificial kidney machines have been developed that make use of dialysis to purify the blood of persons whose kidneys have ceased to function. Known as hemodialysis, this procedure has saved the lives of many persons suffering from renal failure. In such machines, blood is circulated on one side of a semipermeable membrane (often cellophane) while a special dialysis fluid is circulated on the other side. The dialysis fluid must be a solution that closely matches the chemical composition of the blood. Metabolic waste products such as urea and creatinine diffuse through the membrane into the dialysis fluid and are discarded, while loss by diffusion of substances necessary to the body (such as sodium chloride) is prevented by their presence in the dialysis fluid. In peritoneal hemodialysis, the dialysis fluid is introduced into the abdominal cavity. Waste products leach from the blood vessels into the fluid, which is later drained from the patient. Home peritoneal dialysis machines that release patients from dependence on hospital dialysis (usually three 4-hr visits weekly) have been available since the 1980s. See diffusiondiffusion,
in chemistry, the spontaneous migration of substances from regions where their concentration is high to regions where their concentration is low. Diffusion is important in many life processes.
..... Click the link for more information. . Dialysis the removal of impurities of low-molecular-weight substances from colloidal systems and solutions of macromolecular compounds by means of semipermeable membranes, or partitions, which pass small molecules and ions but hold back colloidal particles and macromolecules. The simplest device for dialysis, a dialyzer, is a pouch or sleeve made of semipermeable material that is filled with the liquid to be purified and immersed in a solvent (a dispersion medium). Cylindrical vessels with a semipermeable membrane instead of a bottom are often used in place of a pouch. The membranes are made of collodion, cellophane, animal and plant membranes, and synthetic materials. Diffusion processes are the basis of dialysis; therefore, it proceeds very slowly. Dialysis may be accelerated by increasing the ratio of the membrane area to the volume of the liquid to be dialyzed, by increasing the temperature, by agitation, by creating a pressure difference across the membrane, and by frequent or continuous replacement of the solvent into which the ions or molecules of the low-molecular-weight substance pass (diffuse) through the membrane. Dialysis in an electric field (electrodialysis) accelerates the removal of electrolytes from dialyzed systems by dozens of times. A simple electrodialyzer consists of three chambers separated by membranes. The liquid to be purified is poured into the central chamber, and electrodes immersed in solvent are located in the side flow chambers. The ions in the stationary electrical field move directly to the corresponding electrodes, penetrating the membrane from the central chamber into the side chambers. Electrodialysis is particularly efficient when ionite membranes made of ion-exchange materials are used. Depending on the sign of the electrical charge on their surface, the membranes pass either cations or anions. Multichamber electrodialyzers with ionite membranes are used in hydrometallurgy, in the atomic industry (to treat effluents, concentrate saline solutions, and separate elements close in properties), and in the desalinization of seawater. Dialysis and electrodialysis are used in many industrial processes, in physicochemical and biological research, and in medicine. The dialysis method, which was called vivi-diffusion, was used in 1913 by the American scientist D. Abel to study the components of the blood of a living organism. The animal’s blood passed from an artery into a vein through colloidal tubes placed in a glass cylinder filled with physiologic solution. Abel’s unit was the basis for the design of the artificial kidney, which is used for hemodialysis. REFERENCESVoiutskii, S. S. Kurs kolloidnoi khimii. Moscow, 1964.
Elektrokineticheskie svoistva kapilliarnykh sistem. Moscow-Leningrad, 1956.
Perry, J. H. Spravochnik inzhenera-khimika, vol. 1. Leningrad, 1969. Page 624. (Translated from English.)
Demineralizatsiia metodom elektrodializa (ionitovye membrany). Moscow, 1963. (Translated from English.)dialysis[dī′al·ə·səs] (physical chemistry) A process of selective diffusion through a membrane; usually used to separate low-molecular-weight solutes which diffuse through the membrane from the colloidal and high-molecular-weight solutes which do not. dialysis1. the separation of small molecules from large molecules and colloids in a solution by the selective diffusion of the small molecules through a semipermeable membrane 2. Med See haemodialysis peritoneal dialysisdialysis
dialysis [di-al´ĭ-sis] (Gr.) 1. the diffusion of solute molecules through a membrane" >semipermeable membrane, normally passing from the side of higher concentration to that of lower. A semipermeable membrane is one that allows the passage of certain smaller molecules of such crystalloids as glucose and urea, but prevents passage of larger molecules such as the colloidal plasma proteins and protoplasm. adj., adj dialyt´ic.2. hemodialysis.continuous ambulatory peritoneal dialysis (CAPD) peritoneal dialysis involving the continuous presence of dialysis solution in the peritoneal cavity; see discussion at peritoneal dialysis.continuous cycling peritoneal dialysis (CCPD) a procedure similar to continuous ambulatory peritoneal dialysis but taking place at night, using a machine to make several fluid exchanges automatically. See discussion at peritoneal dialysis.dialysis dysequilibrium syndrome a condition occasionally seen following overly rapid hemodialysis, characterized by increased intracranial pressure that causes nausea, headache, vomiting, restlessness, and a decreased level of consciousness. The neurological complications may lead to coma and death if not treated. The cause of this syndrome is thought to be the rapid decrease in the blood urea nitrogen that accompanies dialysis. Called also dialysis dysequilibrium.extracorporeal dialysis dialysis by a hemodialyzer; see also hemodialysis.intermittent peritoneal dialysis (IPD) an older form of peritoneal dialysis in which dialysis solution is infused into the peritoneal cavity, allowed to equilibrate for 10 to 20 minutes, and then drained out. See discussion at peritoneal dialysis.kidney dialysis hemodialysis.peritoneal dialysis see peritoneal dialysis.renal dialysis hemodialysis.di·al·y·sis (dī-al'i-sis), 1. A form of filtration to separate crystalloid from colloid substances (or smaller molecules from larger ones) in a solution by interposing a semipermeable membrane between the solution and dialyzing fluid; the crystalloid (smaller) substances pass through the membrane into the dialyzing fluid on the other side, the colloids do not. 2. The separation of substances across a semipermeable membrane on the basis of particle size or concentration gradients. 3. A method of artificial kidney function. [G. a separation, fr. dialyo, to separate] dialysis (dī-ăl′ĭ-sĭs)n. pl. dialy·ses (-sēz′) 1. The separation of smaller molecules from larger molecules or of dissolved substances from colloidal particles in a solution by selective diffusion through a semipermeable membrane.2. Medicine Any of several techniques, especially hemodialysis and peritoneal dialysis, in which filtration through a semipermeable membrane is used to remove metabolic wastes and excess fluid from the blood of people with kidney failure.
di′a·lyt′ic (-ə-lĭt′ĭk) adj.di′a·lyt′i·cal·ly adv.dialysis Nephrology The separation of molecules in solution based on differences in size; in renal failure, dialysis is used to separate macromolecules from low-molecular-weight molecules, using a semipermeable membrane Therapeutics The clearance of a drug by a hemodialysis unit. See Hemodialysis, Peritoneal dialysis. di·al·y·sis (dī-al'i-sis) 1. A form of filtration to separate crystalloid from colloid substances (or smaller molecules from larger ones) in a solution by interposing a semipermeable membrane between the solution and water; the crystalloid (smaller) substances pass through the membrane into the water on the other side, the colloids do not.
Synonym(s): diffusion (2) . 2. The separation of substances across a semipermeable membrane on the basis of particle size and/or concentration gradients. 3. A method of artificial kidney function. [G. a separation, fr. dialyo, to separate]dialysis Separation of substances in solution by using membranes through which only molecules below a particular size can pass. Dialysis is the basis of artificial kidney machines.dialysis a process by which small molecules can be separated from larger ones using a fine semipermeable membrane, e.g. cellophane or visking tubing, to contain the larger molecules, but which allows the smaller molecules to pass through into the water on the other side. The kidney machine, used in cases of kidney disease or failure, works on the dialysis principle, with arterial blood from the patient's arm being pumped through the dialysis tube then back into a vein. Holes in the tubing allow small molecules such as glucose, salt and urea to diffuse out into a bath of water, salts and glucose, while leaving behind the proteins such as albumin in the blood.DialysisA process of filtering and removing waste products from the bloodstream. Two main types are hemodialysis and peritoneal dialysis. In hemodialysis, the blood flows out of the body into a machine that filters out the waste products and routes the cleansed blood back into the body. In peritoneal dialysis, the cleansing occurs inside the body. Dialysis fluid is injected into the peritoneal cavity and wastes are filtered through the peritoneum, the thin membrane that surrounds the abdominal organs.Mentioned in: Alport Syndrome, Glomerulonephritis, Kidney Transplantation, Shigellosis, Thrombolytic Therapydi·al·y·sis (dī-al'i-sis) 1. Filtration to separate crystalloid from colloid substances (or smaller molecules from larger ones) in a solution by interposing a semipermeable membrane between solution and dialyzing fluid; crystalloid (smaller) substances pass through membrane into dialyzing fluid on other side, colloids do not. 2. Separation of substances across a semipermeable membrane on basis of particle size or concentration gradients. 3. Method of artificial kidney function. [G. a separation, fr. dialyo, to separate]Patient discussion about dialysisQ. I am upset by the lack of privacy at dialysis centers. Does anyone see their nephrologist in private office? My nephrologist comes to see me and examine me while I am receiving dialysis. I understand his talking to me but the exam is objectionable and I am unable to ask personal questions because everyone is listening. I am told they are all old and don't hear us but that is patronizing and extremely rude. Are there rules against this? Why can't we have office visits where there is some privacy?A. I live in Sault Ste Marie Ontario Canada and if you need to ask personal questions you can make an appointment to see your doctor in the clinic.
But when I was in Calgary Alberta they would make you a appointment every 3 months to see the doctor. Q. why the renal doctor told my husband that he needs to eat a dozen of egg a week for protein,how it will help? it won`t afect his cholesterol,also i would like to know what role the protein plays on his treatment and what other foot its rich in protein that he can can take,without causing problems to his health.A. if i understand correctly, your husband is diabetic. like my grandfather he probably developed a "Diabetic nephropathy" which is a long name to: kidney being destroyed because of blood vessels clotted by diabetes. because of that destruction the kidneys allow protein to go out in the urine. this is a dangerous situation,a protein in the name of "albomin" helps our blood to hold fluids in blood vessels. without it fluid will leave the blood and go to our organs. not a good situation. so he needs a lot of proteins.
here is a list of a 100 protein rich foods:
http://smarterfitter.com/blog/2007/10/28/100-most-protein-rich-vegetarian-foods/
More discussions about dialysisdialysis
Related to dialysis: peritoneal dialysis, kidney failure, hemodialysis, Kidney DialysisWords related to dialysisnoun separation of substances in solution by means of their unequal diffusion through semipermeable membranesRelated Words- chemical analysis
- qualitative analysis
- pheresis
- apheresis
- haemodialysis
- hemodialysis
- osmosis
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