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amniotic sac

An amniotic fluid-filled, thin membranous sac, which surrounds the embryo of amniote vertebrates; it provides a fluid cushion, prevents dehydration and acts as a waste receptacle during embryonic development.


Obstetrics A popular term for the amniotic sac, see there.

Patient discussion about membranes

Q. HYALINE MEMBRANE DISEASE in pre-mature infants;what are the causes of it in pregnant women?

A. the cause of Hyaline Membrane disease is pre-mature birth. while the fetus develop, about in the 29th week a substance called surfactant is created in the lungs. this substance's function is to change the surface tension of the fluid in the lungs- therefore decreasing it's force. the surface tension tends to shrink the lungs and can cause the lungs to collapse. so a premature baby wouldn't be able to breath properly.

Q. For those that had an epimacular membrane removed, how long was it before your eye healed? How was your vision afterwards? Do you now require or benefit from glasses?

A. Epimacular membrane removal can be associated with a variety of ocular conditions and therefore the healing process varies tremendously depending on the underlying pathology. Furthermore, this condition may recur.

More discussions about membranes
References in periodicals archive ?
The influence of support layer on mass transport of homologous series of alcohols and esters through composite pervaporation membranes.
The combination of rising air bubbles, the resulting hydraulic cross-flow, and the seaweed-like movement of the membrane filters ensures that even sludge, hair, and other fibrous components are dislodged from the membranes and moved safely out of the system.
Cellulose Acetate (CA) was one of the first polymeric microporous membranes to be used for processing pharmaceuticals.
The cost to recompress the gas has kept membranes from competing with conventional methods, he says.
In the United States, roofing manufacturers are just stepping up to warranty their membranes with a greenroof component.
The final expulsion step of the maturing virus particles seemed to result in some disruptions to the plasma membrane.
In general, preparation of composite membrane includes the introducing functional groups to PVDF membrane for adsorbing metal ions, and reducing the absorbed metal ions into metal NPs [18], Although several composite membranes have been reported [13, 17, 18], these composite membranes cannot separate the product from reactants because the formed metal NPs distributed both on membrane surface and in membrane pores results in the product always companied by the reactant in the whole process.
Among these methods, blending with inorganic materials especially nanoparticles has attracted much interest due to their simple operation and efficient method for designing new materials to improve performance of the hydrophobic membranes [3].
Keeping membranes clean, permeable and functional is a great challenge to membrane desalination technologies.
Quite relevantly, the talk about biofuels mandates mentioning industrial membranes which had been proven to be very crucial in the field of chemical process industry.
Among the scopes of the conference, mention can be made of membrane for fuel cell and energy applications, membrane for gas and vapor separation, membrane in petroleum industries, membrane for water and wastewater treatment, membrane for bio-refinery applications, bio-membranes, nano-membranes, membrane bioreactors, advanced materials for membrane fabrication, membrane contactors and multifunctional reactors, membranes characterization and modification, membranes for food and bio-product applications and membrane for pharmaceutical and medicine applications.

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