WordNet

increase the likelihood of (a response); "The stimulus facilitates a delayed impulse"
make easier; "you could facilitate the process by sharing your knowledge" (同)ease, alleviate
(physics) the process in which there is movement of a substance from an area of high concentration of that substance to an area of lower concentration
the spread of social institutions (and myths and skills) from one society to another

PrepTutorEJDIC

…‘を'容易にする,楽にする,助ける,促進する
放散,発散,拡散[作用] / 普及,流布 / (文体などの)散漫,冗漫

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2013/02/17 09:25:50」(JST)

wiki en

Facilitated diffusion in cell membrane, showing ion channels and carrier proteins

Not to be confused with diffusion. Facilitated diffusion is not a type of diffusion (thermal motion) but a type of transport process.

Facilitated diffusion (also known as facilitated transport or passive-mediated transport) is a process of passive transport (as opposed to active transport), with this passive transport aided by integral membrane proteins. Facilitated diffusion is the spontaneous passage of molecules or ions across a biological membrane passing through specific transmembrane integral proteins. The facilitated diffusion may occur either across biological membranes or through aqueous compartments of an organism.^[1] Polar molecules and charged ions are dissolved in water but they cannot diffuse freely across the plasma membrane due to the hydrophobic nature of the fatty acid tails of phospholipids that make up the lipid bilayers. Only small nonpolar molecules, such as oxygen can diffuse easily across the membrane. All polar molecules are transported across membranes by proteins that form transmembrane channels. These channels are gated so they can open and close, thus regulating the flow of ions or small polar molecules. Larger molecules are transported by transmembrane carrier proteins, such as permeases that change their conformation as the molecules are carried through, for example glucose or amino acids. Polar molecules, such as retinol or lipids are poorly soluble in water. They are transported through aqueous compartments of cells or through extracellular space by water-soluble carriers as retinol binding protein. The metabolites are not changed because no energy is required for facilitated diffusion. Only permease changes its shape in order to transport the metabolites. The form of transport through cell membrane which modifies its metabolites is the group translocation transportation.

Glucose, sodium ions and chloride ions are just a few examples of molecules and ions that must efficiently get across the plasma membrane but to which the lipid bilayer of the membrane is virtually impermeable. Their transport must therefore be "facilitated" by proteins that span the membrane and provide an alternative route or bypass.

Various attempts have been made by engineers to mimic the process of facilitated transport in synthetic (i.e., non-biological) membranes for use in industrial-scale gas and liquid separations, but these have met with limited success to date, most often for reasons related to poor carrier stability and/or loss of carrier from the membrane.

References

^ Pratt, Charlotte Amerley; Voet, Donald; Voet, Judith G. (2002). Fundamentals of biochemistry upgrade. New York: Wiley. pp. 264–266. ISBN 0-471-41759-9.

Facilitated Diffusion - Description and Animation

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English Journal

Factors influencing fluoride ingestion from dentifrice by children.

Kobayashi CA, Belini MR, Italiani Fde M, Pauleto AR, Julianelli de Araujo J, Tessarolli V, Grizzo LT, Pessan JP, Machado MA, Buzalaf MA.SourceDepartment of Pediatric Dentistry, Orthodontics and Public Health, Bauru Dental School, University of Sao Paulo, Bauru, Brazil Department of Biological Sciences, Bauru Dental School, University of Sao Paulo, Bauru, Brazil.
Community dentistry and oral epidemiology.Community Dent Oral Epidemiol.2011 Oct;39(5):426-32. doi: 10.1111/j.1600-0528.2011.00615.x. Epub 2011 May 9.
Kobayashi CAN, Belini MR, Italiani FM, Pauleto ARC, Julianelli de Araujo J, Tessarolli V, Grizzo LT, Pessan JP, Machado MAAM, Buzalaf MAR. Factors influencing fluoride ingestion from dentifrice by children. Community Dent Oral Epidemiol 2011; 39: 426-432. c 2011 John Wiley & Sons A/S Abstract?
PMID 21557754

Japanese Journal

取引の流れによるイノベーション波及の理解

井上寛康
大阪産業大学経営論集 12(1), 55-72, 2010-10
… If we want to find the environment where innovations are facilitated, the preferred data is the number of transactions, not the gross amount of transactions because the number of firms directly means the extent of the competition in the transactions. …
NAID 110007975312

Related Pictures

★リンクテーブル★

リンク元	「受動拡散」「促進拡散」「促通拡散」
関連記事	「facilitate」「facilitated」「diffusion」

「受動拡散」

　　[★]

英: passive diffusion
関: 拡散

		濃度勾配	エネルギー	飽和
受動拡散	passive diffusion	従う	不要	しない
能動拡散	active diffusion	逆らう	必要	する
促通拡散	facilitated diffusion	従う	不要	する