巻号一覧
17 巻 (1992)
- 6 号 p. 352-
- 5 号 p. 274-
- 4 号 p. 216-
- 3 号 p. 128-
- 2 号 p. 58-
- 1 号 p. 2-
17 巻, 3 号
選択された号の論文の9件中1～9を表示しています
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笠原 道弘1992 年 17 巻 3 号 p. 128-134
発行日: 1992/05/01
公開日: 2011/03/04
ジャーナル フリーRecent advances in the studies of glucose transport in animal cells are reviewed. Five subtypes of glucose transporters of facilitated diffusion have been found. They differ in tissue distribution. One of them, GLUT 1 localizes in blood-tissue barriers, such as blood-brain barrier, blood-ocular barrier and placental barrier. Homologous transporters are found in prokaryotes as well as lower eukaryotes. They traverse the membrane 12 times, according to hydropathy analysis and the molecular weights of which are around 50K. Homology of membrane segments is higher than that of hydrophilic parts. Regulation by insulin of glucose transport in adipocytes and muscles is mainly done by the recycling of vesicles containing glucose transporters between microsomes and plasma membrane. Recent rapid progress in moleluar biology of glucose transport may enable us to clarify the molecular mechanism of membrane transport.抄録全体を表示PDF形式でダウンロード (1123K) -
石井 哲郎1992 年 17 巻 3 号 p. 135-141
発行日: 1992/05/01
公開日: 2011/03/04
ジャーナル フリーMovement of amino acids into and out of animal cells is mediated by various types of transport system. More than 15 transport systems are well characterized, and they can be classified by two criteria. First, they may accept mainly zwitterionic, cationic or anionic amino acids as substrate and second, they can be either Na+ dependent or independent. Each transport system seems to be composed of system-specific carrier protein (s). Recently, the molecular cloning of two carrier proteins have been reported. One carrier is specific for γ-aminobutyric acid (GABA), a neurotransmitter present in central nervous system. In this case, the carrier protein was first highly purified and the amino acid sequence of N-terminal region was utilized in cloning. The other one is specific for basic amino acid such as L-arginine, L-lysine, and L-ornithine. This carrier protein was first cloned as the receptor for ecotropic murine leukaemia viruses, and later it was identified as the System y+ carrier. In other studies, carrier proteins for Systems XAG- and A are highly purified, and some carriers are expressed in Xenopus oocytes after injection of mRNAs from mammalian cells or tissues. These results can serve as means to obtain cDNA clones corresponding to carrier genes.抄録全体を表示PDF形式でダウンロード (993K) -
高野 幹久1992 年 17 巻 3 号 p. 142-152
発行日: 1992/05/01
公開日: 2011/03/04
ジャーナル フリーThe present review is mainly concerned with the transport mechanisms of drugs in the plasma membranes of the renal epithelial cells. Organic anions and cations are actively secreted from plasma to filtrate in the proximal tubules. Studies with isolated membrane vesicles have generated a great deal of information about the transport mechanisms of organic ions in basolateral and brush-border membranes. p-Aminohippurate (PAH ; an organic anion) is actively transported in basolateral membranes by two functionally linked transport systems, Na+/dicarboxylate cotransporter and dicarboxylate/PA H exchanger. In rat brush-border membranes, PAH is probably transported by two distinct transport systems, anion exchanger and potential-sensitive transport system. On the other hand, tetraethylammonium (TEA ; an organic cation) is transported by a potential-sensitive, carrier-mediated system in basolateral membranes. In brush-border membranes, TEA is actively transported by H+/TEA antiport system. Thus, the vesicle studies have provided new insights into our understanding of renal tubular transport mechanisms of drugs.抄録全体を表示PDF形式でダウンロード (1341K) -
柳下 宏, 外赤 隆二, 中山 昇, 北本 大, 中根 堯1992 年 17 巻 3 号 p. 153-165
発行日: 1992/05/01
公開日: 2011/03/04
ジャーナル フリーThe preparation of asymmetric polyethersulfone (PES) membranes by the phase inversion process was investigated. Interactions among the polymer, solvents and gelating solutions were also investigated to determine the suitable solvent and gelating solution on the basis of the physicochemical criteria. For such purpose, viscosity change of the polymer solutions in dissolution process of the polymer, mixing heat of a solvent and a gelating solution, effusion rate of a solvent from a casting solution in gelation process, and gelation point were measured, respectively. The results obtained from those physicochemical measurements and membrane preparation experiments showed that NMP was suitable for the solvent and ethanol for the gelating solution.
The membrane prepared from the casting solution composed of 30 wt% polyethersulfone and 70 wt% NMP, using ethanol as a gelating solution by the phase inversion process exhibited the separation factor α (CO2/CH4) of 40 with the CO2 flux of 1.1×10-6 [cm3 (STP) /cm2·sec·cmHg].抄録全体を表示PDF形式でダウンロード (7574K) -
高澤 啓二, 菊池 武彦, 倉持 智宏, 伊保内 賢1992 年 17 巻 3 号 p. 166-178
発行日: 1992/05/01
公開日: 2011/03/04
ジャーナル フリーWe studied permeation behavior for blended or laminated membrane of polydimethylsiloxane (PDMS), polyarylate (PAR), poly (4-methylpentene-1) (PMP) and 1, 2-polybutadiene (1, 2-PB).
As a result shows, in blended system, separation factor of PAR /1, 2-PB system is a value of 4.80, and laminated system of PAR /1, 2-PB system is 5.51.
In the case of laminated membranes, PDMS or 1, 2-PB laminating on the high strength film such as PAR and PMP, obtain significantly excellent separation membranes. These are because of progressing oxygen affinity of PDMS or 1, 2-PB on laminating film.抄録全体を表示PDF形式でダウンロード (5258K) -
第6報中空糸ミニ・モジュールのGPCを用いた分画特性の測定大矢 晴彦, 佐藤 弓子, 浦山 豊, 根岸 洋一1992 年 17 巻 3 号 p. 179-192
発行日: 1992/05/01
公開日: 2011/03/04
ジャーナル フリーFor the purpose to establish a standard method for determining retention characteristics of hollow fiber ultrafiltration modules, ultrafiltration experiments of aqueous mixed solutions of polyethylene glycoles (PEG) and dextrane (DEX) were carried out using six mini-modules, of which membrane materials were polyethersulfone for two, polysulfone for two and polyacrylonitrile for two modules.
The following operating conditions are strongly recommended for this purpose.
1. The effect of concentration polarization should be eliminated with mass transfer coefficients calculated using Lévêque's equation, to obtain intrinsic retention R =1-Cp/Cm.
2. With the increase of the operating pressure, molecular cut-off at 90% R decreases and gradient of the molecular cut-off curve of R vs. molecular weight decreases.
Therefore, the gradient of the curve should be steap as far as the operating pressure to be allowed enough low.
3. Concentration of each solute will be around 500 mg/l not to be affected by the solute adsorption on the membrane.抄録全体を表示PDF形式でダウンロード (1353K) -
S.I. Semenova, H. Ohya, T. Higashijima, Y. Negishi1992 年 17 巻 3 号 p. 193-196
発行日: 1992/05/01
公開日: 2011/03/04
ジャーナル フリーAsymmetric polyimide membranes were prepared using various coagulants such as diethylether, n-hexane, acetone, toluene, methanol, o-xylene, ethanol, 1, 4-dioxane, water and ethylene glycol. It was found that coagulants having viscosities lower than 0.8 mPa·s give good shaped membranes and that the as-cast film does not coagulate or is broken during immersion into coagulants having higher viscosities than 1.2 mPa·s. The as-cast film immersed in ethanol with a viscosity of 1.0, is broken during hand treatment. Coagulants of lower viscosity might penetrate more quickly into the as-cast film, causing it to solidify but still allowing enough time to form an interlocked porous structure. SEM observation showed that a closed-pore structure is formed at low temperature, versus open-pore at high temperature, using the same successful coagulant such as hexane and toluene. The effective thickness calculated based on measured permeabilities increases in the sequence of N2, CO2, and liquid and vapor EtOH, i. e., 2.7, 3.9, 6.0, and 6.0 μm, respectively, for membranes coagulated in toluene at 293 K.抄録全体を表示PDF形式でダウンロード (1075K) -
大矢 晴彦, 本多 淳, リファイド M. ヌル, 根岸 洋一1992 年 17 巻 3 号 p. 197-202
発行日: 1992/05/01
公開日: 2011/03/04
ジャーナル フリーIn the preparation of asymmetric sulfonated polyether sulfone (SPES) membranes, the sulfonation of polyether sulfone (PES) was carried out by both a surface sulfonation method and a polymer sulfonation method. The resulting membranes, as well as ordinary PES membranes, were tested for the separation of 50% carbon dioxide and 50% methane gases mixtures, and their ion exchange capacities were also determined. Permeabilities and separation factors were determined for both types of membranes as function of solvent evaporation times varying from 2 to 6 minutes, casting temperatures varying from 60 to 100 °C, and in the case of polymer sulfonated membranes, permeabilities and separation factors were also determined as function of polymer concentrations varying from 15 to 25 wt%. Permeabilities obtained with surface-sulfonated membranes were not significantly higher than those observed for PES membranes, but the permeabilities for polymer-sulfonated membranes were significantly higher. Separation factors obtained with surface-sulfonated membranes were lower than those of PES membranes, and those of the polymer-sulfonated membranes were significantly higher. Ion exchange capacities obtained with surface-sulfonated membranes were not significantly higher than those of the PES membranes, but those of the polymer-sulfonated membranes were significantly higher.抄録全体を表示PDF形式でダウンロード (1200K) -
入谷 英司, 板野 雄太, 村瀬 敏朗1992 年 17 巻 3 号 p. 203-206
発行日: 1992/05/01
公開日: 2011/03/04
ジャーナル フリーThe body-feed method, in which fine particles are admixed to the proteinaceous solutions to be filtered, is presented to form dynamic ultrafiltration membranes and compared with the conventional precoat method. It is shown that the ratio of the body-feed to solute concentrations is an important factor to maintain the high solute rejection, and that there exists an optimum filtration pressure in view of both the solute rejection and the filtration rate.抄録全体を表示PDF形式でダウンロード (429K)
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