scholarly journals ON THE PERMEABILITY OF THE STOMACH MUCOSA FOR ACIDS AND SOME OTHER SUBSTANCES

1939 ◽  
Vol 23 (2) ◽  
pp. 263-274 ◽  
Author(s):  
Torsten Teorell
Keyword(s):  
Gastric Juice ◽  
Stomach Content ◽  
Diffusion Theory ◽  
Weak Acids ◽  
Permeable Membrane ◽  
Alkali Ions ◽  
Stomach Mucosa ◽  
Other Substances ◽  
Concentration Changes ◽  
Alkali Chlorides

1. Solutions approximately isotonic with blood of strong and weak acids, several salts, glucose, and glycine were introduced in the resting stomachs of cats. The concentration and volume changes were recorded. 2. It was found that the stomach mucosa was permeable to the majority of the ions tested. There was also a permeability in the opposite direction from the blood (mucosa) to the stomach content, particularly of alkali chlorides. Poorly permeable substances were glucose, glycine, and sodium iodate. Pure weak acids such as acetic acid penetrated very rapidly. 3. The electrolyte concentration changes in the stomach content (or gastric juice) are pictured as an exchange diffusion; for instance, the hydrogen ions of an acid are exchanged against alkali ions of the mucosa or blood. 4. It is pointed out that the concept of the mucosa as an ion permeable membrane could be used as the foundation of a "diffusion theory," which can explain the acidity and chloride variations of the gastric juice without postulating neutralizing or diluting secretions.

scholarly journals The diffusion capsule, a novel device for the addition of a solute at a constant rate to a liquid medium. Its application to metabolic regulation

1971 ◽  
Vol 121 (2) ◽  
pp. 293-297 ◽  
Author(s):  
S. J. Pirt
Keyword(s):  
Metabolic Regulation ◽  
Diffusion Theory ◽  
Culture Technique ◽  
Shake Flask Culture ◽  
Concentrated Solutions ◽  
Permeable Membrane ◽  
Novel Device ◽  
Constant Rate ◽  
Substrate Diffusion ◽  
Micro Organisms

The diffusion capsule consists of a cylindrical container that can be completely filled with a solution and sealed with a small semi-permeable membrane at one end. In use, the capsule is immersed in an agitated liquid. Experiments on concentrated solutions in the capsule showed that, contrary to diffusion theory, the rate of diffusion of solute (sugars or amino acids) out of the capsule remained virtually constant until about 65% of the solute had diffused out of the capsule. Thus the device has been used to maintain constant material feed rates for periods exceeding 30h. The capsule is a simple and compact substitute for a pump and is superior to a pump for small feed rates in many applications. The capsule greatly extends the scope of the shake-flask culture technique for micro-organisms in that substrate-limited growth, possibly the aspect of greatest interest, is readily achieved simply by dropping in the flask a capsule containing the substrate. Diffusion feed should facilitate study of the metabolism of toxic substrates: also it is likely to provide an improved means for supplying a pulse of tracer to a culture.

Evaluation of Carcinoembryonic Antigen Levels in Gastric Juice, Stomach Mucosa and Plasma in High-Risk and Gastric Cancer Patients

Oncology ◽  
1986 ◽  
Vol 43 (3) ◽  
pp. 149-153 ◽  
Author(s):  
Mauro Castelli ◽  
Stefano Guadagni ◽  
Anna Bagnato ◽  
Maria Antonietta Pistoia ◽  
Manlio Carboni ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
High Risk ◽  
Carcinoembryonic Antigen ◽  
Gastric Juice ◽  
Cancer Patients ◽  
Stomach Mucosa ◽  
Gastric Cancer Patients

Elemental mass loss in silicate minerals during x-ray analysis

1990 ◽  
Vol 48 (4) ◽  
pp. 804-805
Author(s):  
P.E. Champness ◽  
R.W. Devenish
Keyword(s):  
Mass Loss ◽  
Current Density ◽  
Damage Mechanism ◽  
Beam Current ◽  
Single Chain ◽  
Plagioclase Feldspar ◽  
X Ray ◽  
Alkali Ions ◽  
Structural Order ◽  
Sheet Silicate

It has long been recognised that silicates can suffer extensive beam damage in electron-beam instruments. The predominant damage mechanism is radiolysis. For instance, damage in quartz, SiO2, results in loss of structural order without mass loss whereas feldspars (framework silicates containing Ca, Na, K) suffer loss of structural order with accompanying mass loss. In the latter case, the alkali ions, particularly Na, are found to migrate away from the area of the beam. The aim of the present study was to investigate the loss of various elements from the common silicate structures during electron irradiation at 100 kV over a range of current densities of 104 - 109 A m−2. (The current density is defined in terms of 50% of total current in the FWHM probe). The silicates so far ivestigated are:- olivine [(Mg, Fe)SiO4], a structure that has isolated Si-O tetrahedra, garnet [(Mg, Ca, Fe)3Al2Si3AO12 another silicate with isolated tetrahedra, pyroxene [-Ca(Mg, Fe)Si2O6 a single-chain silicate; mica [margarite, -Ca2Al4Si4Al4O2O(OH)4], a sheet silicate, and plagioclase feldspar [-NaCaAl3Si5O16]. Ion- thinned samples of each mineral were examined in a VG Microscopes UHV HB501 field- emission STEM. The beam current used was typically - 0.5 nA and the current density was varied by defocussing the electron probe. Energy-dispersive X-ray spectra were collected every 10 seconds for a total of 200 seconds using a Link Systems windowless detector. The thickness of the samples in the area of analysis was normally 50-150 nm.

Amoxycillin and ampicillin are not transfered to gastric juice irrespective of Helicobacter pylori status or acid blockade by omeprazole

2001 ◽  
Vol 120 (5) ◽  
pp. A588-A588
Author(s):  
R ORTIZ ◽  
L ABREU ◽  
S CALLAFATTI ◽  
A CORAZZA ◽  
M DEGUER ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Gastric Juice

Biochemical Study of the Large Molecular Constituents of Gastric Juice

1955 ◽  
Vol 29 (6) ◽  
pp. 1017-1023 ◽  
Author(s):  
Virginia Richmond ◽  
Ranwel Caputto ◽  
Stewart Wolf
Keyword(s):  
Gastric Juice ◽  
Biochemical Study

The Secretion of Halogens into the Gastric Juice

1954 ◽  
Vol 27 (1) ◽  
pp. 98-112 ◽  
Author(s):  
E. Heinz ◽  
K.J. Öbrink ◽  
H. Ulffendahl
Keyword(s):  
Gastric Juice
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