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        검색결과 31

        2.
        2015.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        스테아르산과 인지질혼합물의 농도변화에 띠르는 유기초박막에 대한 안정성을 조사하였다. 스 테아르산과 인지질 혼합물 유기초박막은 ITO glass에 LB법을 사용하여 제막하였다. 전기화학적 특성은 NaClO4 용액에서 3 전극 시스템으로 순환전압전류법을 사용하여 초기 1650 mV에서 최종 퍼텐셜 -1350 mV 까지 측정하였다. 그 결과 스테아르산과 인지질의 혼합물 유기초막은 순환전압전류도표로부 터 산화전류로 인한 비가역공정으로 나타났다. 스테아르산과 인지질혼합물 LB막(몰비 1:1, 1:2, 1:3)에 서 확산계수(D)는 0.01 N NaClO4에서 각각 1.4x10-3, 1.7x10-3 및 1.6x10-3 (cm2/s)로 산출되었다.
        4,000원
        3.
        2014.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        포화지방산과 인지질(DMPC)혼합 LB막에 대한 전기화학적 특성을 조사하였다. 포화지방산과 DMPC 혼합 단분자 LB막은 ITO glass에 Langmuir-Blodgett법을 사용하여 제막하였다. 전기화학적 특 성은 NaClO4 용액에서 3 전극 시스템 (Ag/AgCl 기준전극, 백금선 카운터 전극 및 LB 필름이 코팅된 ITO 작업 전극)으로 순환전압전류법을 사용하여 측정하였다. 그 결과 포화지방산과 인지질(DMPC)의 LB막은 순환전압전류도표로부터 산화전류로 인한 비가역공정으로 나타났다. 포화지방산과 인지질 (DMPC)혼합(몰비 1:1) LB막(C14, C16, C18, C20)에서 확산계수(D)는 0.05 N NaClO4에서 각각 1.2x10-3, 2.1x10-3, 1.4x10-4 및 1.1x10-3 cm2/s로 산출되었다.
        4,000원
        4.
        2012.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        우리는 순환전압전류법에 의한 폴리이미드와 인지질혼합 나노LB 필름에 대한 전기화학적 특성을 조사하였다. polyamic acid와 인지질 단분자 LB막은 ITO glass에 Langmuir-Blodgett법을 사용하여 제막하였다. 전기화학적 특성은 KClO4 용액에서 3 전극 시스템 (Ag/AgCl 기준전극, 백금선 카운터 전극 및 LB 필름이 코팅된 ITO 작업 전극)으로 순환전압전류법을 사용하여 측정하였다. 측정 범위는 연속적으로 1650 mV로 산화시키고, 초기전위인 -1350 mV로 환원시켰다. 주사속도는 각각 50, 100, 150, 200 및 250 mV/s였다. 그 결과 polyamic acid와 인지질 혼합물의 LB 필름은 순환전압전류도표로부터 환원전류로 인한 비가역공정으로 나타났다. Polyamic acid와 인지질혼합 LB막에서 확산계수(D)효과는 LAPC를 사용한 경우가 LLPC를 사용한 것 보다 확산계수 값이 적었다.
        4,000원
        5.
        2012.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        우리는 순환전압전류법에 의한 LB 필름에 대한 전기화학적 특성을 조사하였다. 인지질 화합물은 ITO glass에 Langmuir-Blodgett법을 사용하여 제막하였다. 0.5, 1.0, 1.5 및 2.0 N NaClO4 용액에서 3 전극 시스템 (Ag/AgCl 기준전극, 백금선 카운터 전극 및 LB 필름이 코팅된 ITO 작업전극)으로 순환전압전류법을 사용하여 전기화학적 측정을 시도하였다. 측정 범위는 연속적으로 1650 mV로 산화시키고, 초기전위인 -1350 mV로 환원시켰다. 그 결과, 인지질 화합물의 LB 필름은 순환전압전류도표로부터 오직 산화전류로 인한 비가역공정으로 나타났다. LB 필름의 확산계수(D) 효과는 인지질 화합물 양의 증가로 인하여 감소하였다.
        4,000원
        6.
        2010.12 구독 인증기관 무료, 개인회원 유료
        Phospholipid hydroperoxide glutathione peroxidase (PHGPx) is a unique antioxidant enzyme involved in reduction of peroxidized phospholipids within biomembranes. To investigate the expression pattern of the PHGPx gene during fetal development, in situ hybridization analyses were performed using mouse FITC-labeled PHGPx cRNA probes in fetal tissues on embryonic days (Ed) 13.5-18.5. During these periods, PHGPx mRNA appeared in the developing telencephalon, diencephalon, spinal cord, and spinal ganglion. In particular, PHGPx mRNA was strongly expressed in pyramidal cells of the cerebral cortex. On Eds 17.5-18.5, PHGPx mRNA was detected in various tissues including liver, intestinal villi and crypt, pancreas, lung, and olfactory epithelium of the nasal cavity. In addition, PHGPx mRNA was highly expressed in the inner ear on Eds 14.5-18.5, brown fat on Ed 17.5, and adrenal gland on Ed 18.5. It is conceivable that PHGPx may act as an important antioxidant against fetal oxidative stress during mouse organogenesis.
        4,000원
        7.
        2010.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was designed to investigate the effects of green tea extract on aluminum-induced damage to phospholipid content in old rat cerebral tissue. The aim of this study was to investigate the possibility that aluminum is the cause of Alzheimer’s disease. Forty Sprague-Dawley old male rats weighing 350±10 g were divided into four groups, consisting of a control group (CON), 40 ppm aluminum sulfate group (Al-40), green tea water extract group (GTWE), and 40 ppm aluminum sulfate and green tea water extract groups (Al-40+GTWE) and kept on their respective diets for 12 weeks. In order to discover the influence of aluminum on cerebral tissue of old male rats, the serum aluminum concentration and phospholipid composition were compared between the aluminum-treated group and the normal group. The results showed that the serum aluminum concentration was higher in the aluminum sulfate-treated group than in the normal group. The cerebral tissue phospholipid concentration decreased significantly in the aluminum sulfate treated group as compared to the normal group. The results of this experiment show that increase of aluminum concentration in experimental animals causes the rise of serum aluminum and phospholipid concentrations, phenomena that are very similar to those shown in Alzheimer’s disease., The results of this experiment, together with reports that aluminum is a cause of neurofibrillary tangles in cerebral tissue, therefore demonstrate the possibility that aluminum is the cause of Alzheimer’s disease. Green tea water extract is also shown to be an effective therapeutic candidate for the treatment of Alzheimer’s disease.
        4,000원
        8.
        2009.10 구독 인증기관·개인회원 무료
        Phospholipid-hydroperoxide glutathione peroxide (PHGPx) is an antioxidant enzyme that reduces lipid hydroperoxides in biomembranes. Here, we cloned and characterized cys-PHGPx from the bumblebee Bombus ignitus (Bi-PHGPx). The Bi-PHGPx gene consists of 4 exons, encoding 168 amino acid residues with a canonical cys-codon at residue 45 and active site residues Gln82 and Trp134. Recombinant Bi-PHGPx, expressed as a 19 kDa protein in baculovirus-infected insect cells, exhibited enzymatic activity against PLPC-OOH and H2O2 using glutathione as an electron donor. Tissue distribution analyses showed the presence of Bi-PHGPx in all tissues examined. Bi-PHGPx transcripts were upregulated by stresses, such as wounding, H2O2 exposure, external temperature shock, and starvation. Under H2O2 overload, the RNA interference (RNAi)-induced thioredoxin peroxidase (BiTPx1)-knock-down B. ignitus worker bees showed upregulated expression of Bi-PHGPx in the fat body. These results indicate that Bi-PHGPx is a stress-inducible antioxidant enzyme that acts on phospholipid hydroperoxide and H2O2.
        9.
        2009.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was performed to investigate the effects of aluminum sulfate administration on the brain tissues of old rats, when given at different concentrations. The experiment attempted to further ascertain whether aluminum exposure cause Alzheimer's disease. Seventy-five aged Sprague-Dawley rats were divided into five groups; a control group, 2 ppm aluminum sulfate group, 20 ppm aluminum sulfate group, 40 ppm aluminum sulfate group, and 200 ppm aluminum sulfate group, and were kept on the respective diets for 12 weeks. In order to understand the influence of aluminum on the brain, serum aluminum concentrations, phospholipid composition, and catecholamine concentrations were compared between the aluminum-treated groups and the normal group. According to the results, serum aluminum was higher in the aluminum sulfate-treated groups than in the normal group. Within the cortex, catecholamine concentrationes were significantly increased but cerebellum and brainstem tissue were significantly decreased, in the aluminum sulfate-treated groups compared to the normal group. For phospholipid composition, phosphatidyl inositol was significantly increased wherase phosphatidyl choline, phosphatidyl ethanolamine, and phosphatidyl serine were significantly decreased in the aluminum sulfate-treated groups versus the normal group. Based on the data, increased aluminum consumption in experimental animals causes increased serum aluminum levels and catecholamine variation. These phenomena are very similar to conditions of Alzherimer's disease. Therfore, the results of this experiment further suggest that aluminum cause Alzherimer's disease, coinciding with reports that aluminum is a cause of neurofibrilly tangles in the brain.
        4,000원
        10.
        2006.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We investigated the electrochemical properties for Langmuir-Blodgett (LB) films mixed with fatty acid (8A5H) and phospholipid (DLPE, DMPC, and DPPA). LB films of 8A5H monolayer and 8A5H-phospholipid mixture were deposited using the Langmuir-Blodgett method on the indium tin oxide(ITO) glass. The electrochemical properties measured using cyclic voltammetry with three-electrode system, an Ag/AgCl reference electrode, a platinum wire counter electrode and LB film-coated ITO working electrode at various concentrations(0.1, 0.5, and 1.0 mol/L) of NaClO4 solution. A measuring range was reduced from initial potential to -1350 mV, continuously oxidized to 1650 mV and measured to the initial point. The scan rate was 50, 100, 150 and 200 mV/s, respectively. As a result, LB films of fatty acid and phospholipid (8A5H/DLPE and DPPA) appeared irreversible process were caused by only the reduction current from the cyclic voltammogram and LB film of 8A5H-DMPC mixture was found to be caused by a reversible oxidation-reduction process.
        4,000원
        11.
        2005.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        대두유에 혼합 토코페롤과 개별 인지질 성분으로 phosphatidyl choline(PC), phosphatidyl ethanolamine (PE), phosphatidyl inpsitol(PI), phosphatidyl serine(PS), phosphatidic acid(PA) 및 phosphatidyl glycerol(PG)를 각각 0.03%, 0.05%(w/w) 처리하여 이들 성분이 50℃의 항온저장 조건에서 대두유의 산가(AV), 과산화물가(POV) 및 OSI에 미치는 영향을 측정하였다. 또한, 대두유의 가열안정성에 미치는 영향을 측정하기 위하여 180℃에서 20시간 동안 가열처리하며 5시간 단위로 시료유를 채취하여 처리시간에 따른 발연점(SP) 변화를 측정하였다. 항온저장에 따른 AV변화에서는 그 항산화 효과가 PA>PC>PI≥PG>PS≥PE의 순서였으며, POV상승 억제 효과는 PA〉PG〉PC〉PS〉PE〉PI의 순서였고, OSI 하락 억제효과는 PI〉PC〉PA〉PG〉PS〉PE의 순서로 나타났다. 이와 같이 동일한 대두유에 대하여도 그 처리효과는 각 측정항목에 따라 서로 다르게 나타났다. 이러한 항온저장과 달리 180℃에서 20시간 동안 가열처리하며 5시간 마다 시료유를 채취하여 발연점 하락 억제효과를 측정한 결과는 PA〉PC〉PG〉PE〉PI〉PS의 순이었다. 상대적으로 혼합 토코페롤 처리군은 산가, 과산화물가 상승 억제 효과가 없을 뿐만 아니라 경우에 따라서는 산화 촉진제로 작용하였으며, OSI에서는 일정 부분의 처리 효과를 인정할 수 있었으나 발연점에서는 무처리군 보다도 오히려 그 하락이 심하여 특히 대두유를 튀김유로 사용할 경우에는 혼합 토코페롤의 처리가 바람직하지 못한 것을 알 수 있었다.
        4,000원
        14.
        2002.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We carried out this subject to observe photoisomerization using 1,2-dioleoyl-sn- glycero-3-phosphocholine(DOPC) mixed with fatty acid containing azobenzene group which has reversible to cis-trans by light irradiation. Spreading solutions for the LB films were prepared in chloroform(5.0×10-5mol/L).We investigated the photoisomerization and property of the organic ultra thin film of fatty acid containing azobenzene was prepared on the hydrophilic ITO(idium tin oxide) glass plate by LB method. As a result, the absorption spectra of 8A5H and DOPC of mixture LB films was induced to photoisomerization by alternating irradiation of ultraviolet and visible light, because the condensation of pure azobenzene monolayers was loosened by the introduction of phospholipid into the monolayers, and the molecular high aggregation in pure azobenzene monolayers is also weakened by the introduction of phospholipid. We found that it was reversibly induced to cis-trans photoisomerization in several solvents and mixture LB films.
        4,000원
        15.
        2000.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We have investgated UV-Vis absorbance to observe the photoisomerization using the mixture solutions in chloroform and LB monolayers mixed with DLPE and 8A5H containing azobenzene which showed reversible cis-trans photoisomerization irradiated by alternate lights. We have found that the absorbance spectrums of the mixture solutions and LB monolayers were reversibly induced to cis-trans photoisomerization irradiated by alternate lights. In addition, the absorbance of both solution and LB monolayer mixed with 8A5H and DLPE were reversibly by alternate temperatures. As a results, the 1:1(by volume) mixture ratio of 8A5H and DLPE was more flexible and reversible cis-trans photoisomerization than the others.
        4,000원
        16.
        1999.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We carried out this subject to observe photoisomerization using 8A5H and phospholipid(DLPC) containing azobenzene group which has reversible to cis-trans by light irradiation. We investigated the photoisomerization and property of the monolayer film on quartz substrate prepared by the mixture of 8A5H and phospholipid deposited using Langmuir-Blodgett(LB) method. It was found that the absorption spectrum of the 8A5H and phospholipid LB monolayer was induced to photoisomerization by alternate light irradiation. And the absorbance of both the solution of mixtures of 8A5H-phospholipid and LB film was reversibly changed by the acid-base exposure and alternate temperatures.
        4,000원
        17.
        1998.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Anti-phospholipid antihodies (aPL) have important roles in various pregnancy complications such as recurrent miscarrige, growth retardation, placental abruption and stillbirth. However, their biological actions on preimplantation development of oocytes are still unclear. In this study, we investigated whether either aPL containing sera or phospholipids could affect in vitro fertilization and development of mouse oocytes. Sera used in this study were collected from three patients and the presence of aPL in the sera was confirmed by enzymatic-linked immunosorbent assay. When mouse oocytes were cultured in a serum-free, Chatot, Ziomek and Bavister (CZB) medium (Experiment 1), addition of aPL-containing sera (10%) to CZB medium did not. significantly (P>0.05) influence sperm penetration of oocytes. However, development to the blastocyst stage was significantly (P<0.05) inhibited by serum addition, and formation of morulae (16-23% vs. 58%) and blastocysts (0-4% vs. 21%) was markedly reduced compared with no addition (Experiment 2). In Experiment 3, pronuclear stage embryos were cultured for 96 h in GZB medium supplemented with 1 g /ml phosphatidyl ethanolamine, 1 g/ml phosphatidyl inositol or 1 g /ml phosphatidyl choline. No increase in embryo development was found after addition of the phospholipids to CZB medium. These results suggest that 1) aPL have an inhibitory role in preimplantation development of mouse embryos, and that 2) the action of aPL may be related to a specific phospholid (s) rather than the tested phospholipids in the present study.
        4,000원
        18.
        1997.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The organization of phospholipid monolayers and their monolayers mixed with fatty acid containing azobenzene on the water surface was investigated by means of the displacement current measurement method. The phase transition from the gaseous phase to the gaseous-fluid phase which accompanies the polar ordering of phospholipid molecules was detected in the range of immeasurably low surface pressure. The molecular area which gives the onset of the transition was determined for phospholipid monolayers. The Maxwell displacement current(MDC) pulses were generated across mixed monolayers due to the photoisomerization of fatty acid containing azobenzene by alternating irradiation of ultraviolet and visible light, because the condensation of pure azobenzene monolayers was loosened by the introduction of phospholipids into the monolayers. The displacement currents generated during light irradiation were also investgated in connection with monolayer compression cycles. It was found that the maximum of MDC appeared at the molecular area just before the initial rise of surface pressure in compression cycles.
        4,000원
        19.
        1996.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Metachromatic properties of admixture of thionine and methylene blue(MB) in aqueous solution and phospholipid bilayer membrane have been studied by absorption spectroscopy. When thionine and MB were mixed, new coaggregate has been formed because of MB was redistributed to thionine aggregate. In phosphlipid bilayer membrane system, the highly concentrated thionine was easily formed the coaggregation with MB moiety independent of MB concentration, and absorption band of admixture were more transferred to short wavelength than aqueous system. In monomeric thionine concentration, the coaggregation band was observed at the middle wavelength between the site of monomeric thionine and the site of dimeric MB in the presence of lipid bilayer membrane.
        4,000원
        20.
        1996.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The liposomes have been developed in many drugs and cosmetics fields. The liposomes prepared with main compounds of the intercellular lipids and lecithin. Amphiphile nonionic surfactants used for (PEG) n-sitosterol(n=5), diethanolamine cetylphosphate. The effect of gelation for liposomes have been on swelling reaction which have been mixed phospholipid with polyol-group at the high temperature. There were very good encapsulated properties of the active ingredients whether hydrophilic-group(magnesium ascorbyl phosphate, allantoin, sodium hyaluronate) and hydrophobic-group(vitamin-E acetate, vitamin-A palmitate). Optimum condition of liposomes were passed five times in the microfluidizer(700bar), wetting reaction temperature was at 95±5℃ for a hours. Particle size distribution of the vesicles should be within range 50-560nm(mean 200nm). The stability of liposomes for the course of time was stabilized for six months at 45℃. Application of the cosmetic was prepared moisturizing cream with liposomes of the phospholipid base.
        4,000원
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