• 한방안이비인후피부과학회지
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• 제19권3호통권31호
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• pp.13-21
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• 2006

Object : We investigated the effect of Gamiokyaek-tang (GOYT) on immediate type hypersensitivity. Methods : We investigated anti-dinitrophenyl (DNP) IgE-mediated passive cutaneous anaphylaxis and acetic acid-induced vascular permeability in rodents. Also perfonned MTT assay and b-hexosaminidase activity is measured in RBL-2H3. Results : GOYT inhibited passive cutaneous anaphylaxis and acetic acid-induced vascular permeability by oral administration. All the concentrations of GOYT from 0.1 to 5 mg/ml didn't have an effect on cell viability and cytotoxicity. b-hexosaminidase release in RBL-2H3 was significantly reduced by 2 and 5 mg/ml of GOYT. Conclusion : These results indicate that GOYT have inhibition effects on immediate type hypersensitivity .

• 대한기계학회논문집A
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• 제31권3호
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• pp.388-394
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• 2007

Many engineering problems require the calculation of effective material properties of a structure which is composed of repeated micro-structures. The homogenization method has been used to calculate the effective (homogenized) properties of composites and several homogenization procedures for different physical fields have been introduced. This research describes the modified homogenization technique for magnetostatic problems. Assuming that the material is periodically repeated, its effective permeability can be prescribed by calculating the homogenized magnetic reluctivity using the finite element analysis of the micro unit cell. Validity of the suggested method is confirmed by comparing the results by the energy based method as well as the widely known homogenization method.

• 대한약학회:학술대회논문집
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• 대한약학회 2001년도 Proceedings of the Pharmaceutical Society of Korea
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• pp.108.2-109
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• 2001

• Macromolecular Research
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• 제12권4호
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• pp.413-421
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• 2004

Sulfonated poly(phthalazinone ether sulfone ketone) (SPPESK) membranes and sol-gel derived SPPESK/silica hybrid membranes have been investigated as potential polymer electrolyte membranes for direct methanol fuel cell (DMFC) applications. In comparison with the SPPESK membrane, the SPPESK/silica membranes exhibited higher water content, improved proton conductivity, and lower methanol permeability. Notably, the silica embedded in the membrane acted as a material for reducing the fraction of free water and as a barrier for methanol transport through the membrane. From the results of proton conductivity and methanol permeability studies, we suggest that the fractions of bound and free water should be optimized to obtain desirable proton conductivities and methanol permeabilities. The highly sulfonated PPESK hybrid membrane (HSP-Si) displayed higher proton conductivity (3.42 ${\times}$ 10$^2$ S/cm) and lower methanol permeability (4.15 ${\times}$ 10$\^$7/ $\textrm{cm}^2$/s) than those of Nafion 117 (2.54 ${\times}$ 10$^2$ S/cm; 2.36 ${\times}$ 10$\^$6/ $\textrm{cm}^2$/s, respectively) at 30$^{\circ}C$. This characteristic of the SPPESK/silica membranes is desirable for future applications related to DMFCs.

• Biomolecules & Therapeutics
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• 제11권2호
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• pp.112-118
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• 2003

1-Methylated $\beta$-carbolines (harmaline and harmalol) and antioxidants (N-acetylcysteine and ascorbate) reduced the loss of cell viability in differentiated PC 12 cells treated with 5 mM glutamate. $\beta$-Carbolines prevented the glutamate-induced decrease in mitochondrial membrane potential, cytochrome c release and caspase-3 activation in PC 12 cells. $\beta$-Carbolines reduced the formation of reactive oxygen species and depletion of glutathione due to glutamate in PC12 cells. $\beta$-Carbolines revealed a scavenging action on hydrogen peroxide and reduced the iron and EDTA-mediated degradation of 2-deoxy-D-ribose. The results suggest that I-methylated $\beta$-carbolines attenuate the cytotoxic effect of glutamate on PC12 cells by reducing the alteration of mitochondrial membrane permeability that seems to be mediated by oxidative stress.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.269-269
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• 2006

The molecular structure of poly(2,6-dimethyl-4,4' -phenylene oxide)-g-poly (styrenesulfonic acid) (PPO-g-PSSA) graft copolymer was designed, and synthesized via living radical polymerization. Obtained graft copolymers were transformed into proton exchange membranes for direct methanol fuel cell (DMFC) application. The performance of the membranes was measured in terms of water uptake, proton conductivity, methanol permeability, and thermal stability. Very low methanol permeability and good proton conductivity were observed by adjusting grafting frequency and PSSA block content.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2005년도 추계학술발표대회 논문집
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• pp.87-90
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• 2005

This paper presents an evaluation of the effect of titanium dioxide nanoparticles in sulfonated poly(ether ether ketone) (SPEEK) with sulfonation degree of 57%. A series of inorganic-organic hybrid membranes were prepared with a systematic variation of titanium dioxide nanoparticles content. Their water uptake, methanol permeability and proton conductivity as a function of temperature were investigated. The results obtained show that the inorganic oxide network decreases the proton conductivity and water swelling. It is also found that increase in inorganic oxide content leads to decrease of methanol permeability. In terms of morphology, membranes are homogeneous and exhibit a good adhesion between inorganic domains and the polymer matrix. The properties of the composite membranes are compared with standard nafion membrane.

• 약학회지
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• 제47권3호
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• pp.154-158
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• 2003

Lincomycin, a selective tyrosinase blocker, has been thought to be effective in the treatment of melanogenesis, ephelis, post inflammatory pigmentation, and facial discoloration. In an attempt to develop a transdermal perparation for lincomycin, this study was designed to examine the appropriate contents of various surfactants and ethanol in the cream preparation. Frans type diffusion cell was used to investigate permeation efficiency of the preparation, and lincomycin in the receptor phase was measured by HPLC. After having a 1.5 hrs of leg time, the permeability of lincomycin was rapidly increased by adding surfactants, and varied with different types of surfactants after 10 hrs, the permeability of Brij 56$^{(R)}$ preparation (501.4$\pm$45 $\mu\textrm{g}$/mι) was greater than that either of Labrasol$^{(R)}$ (263.9$\pm$33.7 $\mu\textrm{g}$/mι) or Tween$^{(R)}$20(386.2$\pm$26.7 $\mu\textrm{g}$/mι). Ethanol also increased the permeability of lincomycin.mycin.

• Journal of electromagnetic engineering and science
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• 제13권2호
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• pp.134-136
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• 2013

This paper examines various aspects of the electromagnetic responses of the ring resonator located in the transverse electromagnetic cell. In addition, an equivalent circuit for the ring resonator is proposed and analyzed based on the electromagnetic phenomenon of the resonator. The equivalent circuit was simply modeled based on the concept of magnetization. A method for achieving a wider operating bandwidth of the negative permeability is provided. The ring resonator with its resonant frequency of 13.56 MHz was designed and its characteristics were examined in terms of S-parameters, effective permeability, loss rate, bandwidth, etc. The circuit and electromagnetic simulation results show an excellent agreement as well as that of theory.

• 한국잡초학회지
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• 제5권1호
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• pp.56-62
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• 1985

벼의 발아후(發芽後) 생육(生育), 중경(中徑)과 근(根) 세포형태(細胞形態) 및 근(根) 세포막(細胞膜) 투과성(透過性)에 대한 butachlor와 1, 8 - naphthalic anhydride(NA)의 상호작용력(相互作用力)을 검토(檢討)하였다. Butachlor와 NA의 단일처리(單一處理)는 독도(獨度)의 증가(增加)와 함께 벼의 중경(中莖) 및 유근(幼根) 신장(伸長)을 현저히 억제(抑制)시키지만 엽초에 대해서는 영향(影響)을 미치지 않았다. Butachlor + NA 처리(處理)로 엽초 신장(伸長)을 증대(增大)되었지만 중경(中莖) 신장(伸長)은 감소(減少)되었다. Butachlor를 단일처리(單一處理)하면 중경(中莖) 근(根) 세포(細胞)의 피층세포(皮層細胞)가 부분적(部分的)으로 파괴된 세포간공극(細胞間空隙)이 형성(形成)되지만, NA를 동시(同時)에 처리(處理)하면 피층세포(皮層細胞)가 파괴된 세포간공극(細胞間空隙)은 더욱 확대(廓大)되었다. 벼의 근(根) 세포막(細胞膜) 투과성(透過性)은 butachlor와 NA의 처리농도(處理濃度) 증가(增加)로 확대(擴大)되지만, butachlor + NA의 처리(處理)로 감소(減少)되는 경향이었다.