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Volume 15, Issue 1
Displaying 1-7 of 7 articles from this issue
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Y. Imanishi, S. Kimura1990 Volume 15 Issue 1 Pages 2-10
Published: January 01, 1990
Released on J-STAGE: March 04, 2011
JOURNAL FREE ACCESSPeptide hormones elicit the effect by binding to the specific receptor in cell membrane. On the other hand, several peptide hormones have been shown to be distributed to the lipid membrane with taking a defined conformation. The peptides are incorporated into the lipid membrane through the hydrophobic interaction, electrostatic interaction, and dipole interaction, etc. Due to these factors, the enkephalin derivative was also shown to interact with the lipid membrane stereoselectively. These findings support the membrane compartment concept, which predicts that the peptide is incorporated into a certain region of the membrane (compartment) where the binding site of the receptor locates, resulted in the enhancement of their association. Opioid receptors exist in three different types, δ, μ, and κ, and the binding sites supposedly locate over, on, and inside membrane, respectively. Several enkephalin derivatives were synthesized and discussed on the relation of the receptor affinity and selectivity with the membrane affinity.View full abstractDownload PDF (1167K) -
Shozo Muranishi1990 Volume 15 Issue 1 Pages 11-18
Published: January 01, 1990
Released on J-STAGE: March 04, 2011
JOURNAL FREE ACCESSVarious biological membranes (barriers) at the sites of drug administration have increased in interest in drug delivery. Epithelial barriers such as gastrointestinal, dermal, nasal, and pulmonary barrier are reviewed at a cellular, biochemical, and anatomical level. Several factors, enzymatic metabolism and membrane permeability, are concerned in drug delivery, Penetration enhancers, for example, act on the various biological barriers at a different extent. Thus absorption enhancers are overviewed, and their enhancing mechanism is presented and discussed from the point of drug delivery system.View full abstractDownload PDF (1201K) -
Masaji Matsuda, Chiyoshi Kamizawa, Kenji Haraya, Woo-Tai Lee1990 Volume 15 Issue 1 Pages 19-24
Published: January 01, 1990
Released on J-STAGE: March 04, 2011
JOURNAL FREE ACCESSIn the research and development of gas separation membranes, it is very important to measure the gas permeabilities of membranes readily and precisely.
In this report, the new type apparatus based on the volumetric method with piston-feeder was developed for the simple, rapid and precise measurement. With this apparatus, the gas permeabilities were measured for microporous glass, silicone rubber, cellulose acetate membrane and polyester film, and the values obtained were in good agreement with ones obtained by the high-vacuum type apparatus. The experiment of the oxygen enrichment as carried out with air through silicone rubber, and observed values were in fair agreement with calculated ones.View full abstractDownload PDF (700K) -
Teruhiko Baba, Masaji Matsuda, Kenji Haraya, Chiyoshi Kamizawa, Woo-Ta ...1990 Volume 15 Issue 1 Pages 25-33
Published: January 01, 1990
Released on J-STAGE: March 04, 2011
JOURNAL FREE ACCESSThe applicability of the newly developed permeability apparatus of the piston-feeder type to the evaluation of the gas diffusion coefficients in membrane were examined using silicone rubber/O2 and/N2 systems at 15°C. The data for the gas diffusivity were obtained by the time lag method and these values were in good agreement with those obtained by the apparatus of the high-vacuum type. Such results were demonstrated for the first time in the case of the volumetric method and suggest that the newly developed permeability apparatus is sufficiently applicable to the evaluations of the diffusivity as well as the permeability, if only the pre-experimental conditions can be set up properly. Meanwhile, it was also actually observed that time lag is much affected with the initial deviation of the gas distribution between the inside and the outside of membrane. This phenomenon is always liable to occur in the case of the volumetric method and the experimental results could be well-described by the Fickian desorption mechanism in the case that the gas concentration in membrane is higher than the equilibrium concentration defined by the outside pressure. From this consideration, the criteria of the initial set-up conditions for the valid evaluations in the repeated measurements were discussed.View full abstractDownload PDF (995K) -
1990 Volume 15 Issue 1 Pages 33
Published: 1990
Released on J-STAGE: March 04, 2011
JOURNAL FREE ACCESSDownload PDF (79K) -
Chiyoshi KAMIZAWA, Masaji MATSUDA, Woo-Tai LEE, Fujio MIZUKAMI, Shuich ...1990 Volume 15 Issue 1 Pages 34-38
Published: January 01, 1990
Released on J-STAGE: March 04, 2011
JOURNAL FREE ACCESSOxygen enrichment membranes containing fixed metal complex carriers were prepared. Schiff bases with cobalt as a ligand were used as metal complex carriers of oxygen. In one type of membrane, Schiff base cobalt complex was coated on the surface of polysulfone support. In another type, after mixing of metal complexes with polymers (silicone or cellulose acetate), the membranes were fabricated. In the former case, the membrane having the permeation rate (O2) of 4.70 × 10-6cm3/cm2·s·cm Hg and separation factor (PO2/PN2) of 3.9 at 1 kg/cm2 was obtained. In latter cases, the membranes having so excellent performances were not prepared, but some informations concerning fixed carrier membranes were obtained.View full abstractDownload PDF (577K) -
[in Japanese]1990 Volume 15 Issue 1 Pages 39-45
Published: January 01, 1990
Released on J-STAGE: March 04, 2011
JOURNAL FREE ACCESSDownload PDF (1427K)
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