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1. Biology
a. A thin, pliable layer of tissue covering surfaces or separating or connecting regions, structures, or organs of a living organism.
b. A semipermeable layer that bounds a cell or an organelle, typically consisting of lipids and proteins.
2. A thin, pliable sheet or layer of natural or synthetic material: the resonating membrane of a kazoo.
3. A piece of parchment.
4. Chemistry A thin sheet of natural or synthetic material that is permeable to substances in solution.

[Latin membrāna, skin, from membrum, member of the body.]

mem′bra·nal (-brə-nəl) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Biology) relating to membranes
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
La membrana del eritrocito esta constituida por un glicocalix (con abundantes carbohidratos), una bicapa lipidica (de proteinas transmembranales y lipidos) y un citoesqueleto membranal (proteinas con disposicion de red, intrincada en la bicapa lipidica).
The ratio of membranal cPKC[beta]II to cytosolic cPKC[beta]II was not significantly altered in the three brain regions at 2 weeks (Figure 4(a)) but dramatically decreased in the prefrontal cortex and hippocampus at 8 weeks (Figure 5(a)).
These differences appear in the molecules effectiveness against different inflammatory diseases and might be related to the antibodies binding to membranal TNF-[alpha] on T cells [28].
Lahat, "Hypoxia reduces the output of matrix metalloproteinase-9 (MMP-9) in monocytes by inhibiting its secretion and elevating membranal association," Journal of Leukocyte Biology, vol.
They differentiate by the morphology of the outer segment made of stacks of membranal disks or invaginations containing the light-sensitive molecule as originally observed by Schultze in 1866 [44].
In these assays, because PS2 is a membranal protein (as mentioned before), we decided to use p-Tau to mark microtubules to identify the localization of PS2.
Protection of membranal lipids against lipid oxidation by vitamin E has been suggested to be the mechanism responsible for the positive influence of dietary vitamin E on the water holding capacity since the integrity of the cell membrane is thought to be associated with drip loss (Asghar et al., 1991).
Shaltiel, "The cleavage of protein kinase A by the kinase-splitting membranal proteinase is reproduced by meprin [beta]," The Journal of Biological Chemistry, vol.
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