• Journal of the Korean Ceramic Society
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• 제38권7호
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• pp.648-653
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• 2001

구연산이 첨가된 0.01 M의 $\beta$-인산칼슘 용액을 수열처리 하여 휘스커 상 수산화아파타이트를 합성할 때 수열처리 온도 및 시간이 휘스커의 생성에 미치는 영향을 관찰하였다. 용액을 30$0^{\circ}C$에서 5시간 수열처리 할 때 c축으로 약 60-80$\mu\textrm{m}$까지 성장하고 비교적 순수한 휘스커를 얻을 수 있었으며 이렇게 합성된 수산화아파타이트 휘스커를 수산화아파타이트 시멘트에 1-2 wt% 첨가하였을 때 그 경화체의 직경인장강도는 약 4-6배까지 증가하였다.

• Journal of the Korean Society of Food Science and Nutrition
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• 제33권7호
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• pp.1092-1097
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• 2004

The objective of the current study was to determine the effects of the crude polysaccharide isolated from fruit body of Pleurotus eryngii on mouse splenocytes, B cells, and macrophages in vitro. The crude polysaccharides directly induced the proliferation of spleen cells in a dose-dependent manner and increased IL-6 and IFN-${\gamma}$ synthesis. The crude polysaccharides also increased the proliferation of B cells in a dose-dependent manner. The production of immunoglobulin Gl, G2a and IgG3 in the presence of the crude polysaccharides was increased progressively in the culture supernatant. When the crude polysaccharide were used in macrophage cell line (RA W264.7) stimulation, there were marked induction of NO synthesis in a dose-dependent manner and IL-6, TNF- r and GM-CSF synthesis. These results suggest that the crude polysaccharide isolated from fruit body of Pleurotus eryngii seem to act as a potent immunomodulator causing augmentation of immune cell activity, and thus could be used as a biological response modifier having possible therapeutic effects against immunological disorders, without any side effects.

• Journal of Applied Biological Chemistry
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• 제58권2호
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• pp.183-187
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• 2015

The electron donating ability, elastase inhibitory, procollagen synthesis and Matrix metalloprotease-1 (MMP-1) activities were measured in order to verify the anti-wrinkle properties of extracts from Buplerum falcatum as a functional ingredient for cosmetic products. Electron donating ability and elastase inhibition activities were 80 and 52% at a dose of $1,000{\mu}g/mL$ of B. falcatum 70% ethanol extract. Pro-collagen synthesis was increased with the increase concentration of B. falcatum extract on CCD-986sk in addition to decrease the amount of protein of MMP-1. The results suggested that B. falcatum extract can be used to reduced electron donating ability, elastase, pro-collagen synthesis and MMP-1 activity and is a potential candidate for cosmedical materials.

• Journal of Powder Materials
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• 제6권3호
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• pp.215-223
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• 1999

The synthesis of $Ni_5Si_2,\;Ni_2Si$ and NiSi has been investigated by mechanical alloying (MA) of Ni-27.9at%Si, Ni-33.3at%Si and Ni-50.0at%Si powder mixtures. As-received and premilled elemental powders were subjected to MA. The as-received Ni powder was spherical and the mean particle size 48.8$\mu$m, whereas the premilled Ni powder was flaky and the mean particle diameter and thickness were found to be 125 and 5$\mu$m, respectively. The mean surface area of the premilled Mi powder particle was 3.5 times as large as that of the as-received Ni powder particle. The as-received Si powder was was 10.0$\mu$m. Self-propagating high-temperature synthesis (SHS) reaction, followed by a slow reaction (a solid state diffusion), was observed to produce each Ni silicide during MA of the as-received elemental powders. In other word , the reactants and product coexisted for a long period of MA of time. Only SHS reaction was, however, observed to produce each Ni silicide during MA of the premilled elemental powders, indicating that each Ni sillicide formed rather abruptly at a short period of MA time. The mechanisms and reaction rates for the formation of the Ni silicides appeared to be influenced by the elemental powder particle size and shape as well as the heat of formation of the products $(Ni_5Si_2$longrightarrow-43.1kJ/mol.at., $Ni_2Si$$\rightarrow$-47.6kJ/mol.at.).

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• 제28권1호
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• pp.32-40
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• 2015

Objectives : Hyaluronic acid(HA) is a mucopolysaccharide, occuring naturally in living organisms. It is one of the most hydrophilic molecules, so it has been known as being related to skin hydration and anti-aging. The purpose of this study is to examine the effects of Angelica acutiloba ethanol extract on hyaluronic acid synthesis. Methods : To determine cytotoxicity and hyaluronic acid synthase 2 gene expression, hyaluronic acid production in HaCaT cells, MTT assay and RT-PCR ELISA was used. Results : There was no cytotoxicity in $50{\mu}g/ml$ concentration Angelica acutiloba extract in MTT assay. Hyaluronic acid synthase 2(HAS2) gene expression was increased by all treated concentration Angelica acutiloba extract. Hyaluronic acid production was higher in $50{\mu}g/ml$ & $100{\mu}g/ml$ concentration Angelica acutiloba extract than control group. Conclusions : Hyaluronic acid production was increased by Angelica Acutiloba extracts. Therefore, We suggest that Angelica acutiloba can make a contribution to the moisturing effect on human skin. Conclusions : Hyaluronic acid production was increased by Angelica Acutiloba extracts. Therefore, We suggest that Angelica acutiloba can make a contribution to the moisturing effect on human skin.

• Journal of Acupuncture Research
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• 제23권2호
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• pp.91-102
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• 2006

Objectives : Ulmus davidiana Planch (UD) has long been known to have anti-inflammatory and protective effects on damaged tissue, inflammation and bone among other functions. Methods : This study was undertaken to address whether the water extract of the bark of UD could modulate proliferation of mouse osteoclasts in vitro and to investigate its effect on cyclooxygenase-2 (COX-2), which converts arachidonic acid to prostaglandin E2 (PGE2) and is highly expressed in osteoclasts. Mouse osteoclasts were tested in vitro for growth inhibition, proliferation cell nuclear antigen expression, and COX-2 activity and expression after treatment with UD extract. Results : Its effects were compared with those of indomethacin (a nonselective COX inhibitor) and celecoxib (a selective COX-2 inhibitor) by Cell viability assay, Cell cycle analysis, Immunohistochemical analysis of PCNA expression, Western blot analysis and PGE2 Enzyme immunoassay (EIA). UD demonstrated a strong growth inhibitory action in both tested osteoclasts cells. The IC50s were $10\;{\mu}g/ml$ for UD, $6\;{\mu}M$ for celecoxib and $42\;{\mu}M$ for indomethacin. UD, as well as celecoxib and indomethacin, suppressed proliferation cell nuclear antigen expression and PGE2 synthesis in osteoclasts. UD inhibited COX-2 expression, whereas celecoxib inhibited COX-2 activity directly. Conclusion : UD selectively and effectively inhibits osteoclasts cell growth in vitro. Inhibitory action of PGE2 synthesis via suppression of COX-2 expression may be responsible for its anti-inflammatory activity.

• The Journal of Korean Obstetrics and Gynecology
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• 제24권4호
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• pp.10-19
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• 2011

Objectives: This study was performed to elucidate the effects of Kwibi-tang extract(KB) on dermal fibroblast. Methods: To demonstrate the effects of KB on dermal fibroblast, we used human dermal fibroblast(F6) and UVB light(30 $mJ/cm^2$) was used to damage to dermal fibroblast. we measured the nitrite production, LDH release in UVB-irradiated dermal fibroblast to elucidate the action-mechanism of KB. Also, we evaluated cell proliferation of dermal fibroblast and the amount of increased PICP, TIMP-1 in dermal fibroblast. Results: 1. KB decreased the cell proliferation of F6 dermal fibroblast in concentration of 50 ${\mu}g/ml$. 2. KB decreased the synthesis of PICP in concentration of 50 ${\mu}g/ml$. 3. KB decreased the synthesis of TIMP-1 in concentration of 50 ${\mu}g/ml$. 4. KB have no effect on the damage in UVB-irradiated F6 dermal fibroblast. Conclusions: From the results, we concluded KB decreases the cell proliferation and collagen synthesis in dermal fibroblast. So we suggest that KB has the anti-hyperplasy of dermal fibroblast.

• Journal of Physiology & Pathology in Korean Medicine
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• 제33권5호
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• pp.267-274
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• 2019

This study aims to evaluate the effects of Shengmaisan (SMS) and three types of ShengmaisanJiaweifang on the inhibitory effect of melanin synthesis in B16F10 cells, the mechanism of action through tyrosinase, and the antioxidant effect through superoxide dismutase (SOD) activity. In this study, we used ShengmaisanJiaweifangs (SMS, SMSRR, SMSAD, SMSAR) to research the whitening effects in B16F10 cell lines. Shengmaisan (SMS) was a herbal medicine composed of Ginseng Radix, Liriopis Tuber, and Schisandrae Fructus. ShengmaisanJiaweifangs included SMSRR (SMS added with Rehmanniae Radix), SMSAD (SMS added with Asparagi Radix) and SMSAR (SMS added with Astragali Radix). We measured the cell viability, the inhibition rate of the melanin biosynthesis, and the activity of tyrosinase and SOD in malignant melanoma, B16F10 cells, to survey the whitening effect and the mechanism of the impact on the sample. As a result, SMSRR significantly suppressed the cell viability of B16F10 at more than $500{\mu}g/m{\ell}$ and significantly inhibited the generation of melanin induced by ${\alpha}$-MSH at more than $250{\mu}g/m{\ell}$. SMSRR ($500{\mu}g/m{\ell}$) decreased the activity of tyrosinase while increased the activity of SOD. Therefore, we considered that the SMSRR would be able to produce high value-added products more SMS if used as a commercial.

• The Korean Journal of Pesticide Science
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• 제2권1호
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• pp.24-31
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• 1998

Chemical derivative synthesis of ricinine, an active compound of Ricinus communis which showed high mortality against brown planthopper (Nilaparvata lugens), was performed to improve its pesticidal activity and the toxicity of 12 synthetic derivatives against major insect pests and phytopathogenic fungi were examined. Carbamate derivatives of ricinine could be synthesized from the precursor of ricinine, chloronorricinine and norricinine, whereas the derivatives were not synthesized from chlororicinic acid and ricinic acid having ketone group of pyridine ring. In organophosphates, reaction with oxon type of phosphate gave better yield than thiono type. Among the organophosphate derivatives of ricinine, thiono type of derivative structure gave $96.3%{\sim}100%$ mortality of the brown planthopper and the two-spotted spider mite (Tetranychus urticae) at 500 ${\mu}g/ml$ level. On the other hand, carbamate derivatives did not show insecticidal activity. In the fungicidal activity of ricinine derivatives, the derivative having amino radical at the 2 position of ricinine gave 85 to 100% of mycelium growth inhibition effect against ten major plant pathogens at the 200 ${\mu}g/ml$ level. In particular, the control value of the derivative on the rice blast (Pyricularia grisea) and barley powdery mildew (Erysiphe graminis) at the 250 ${\mu}g/ml$ level in vivo under greenhouse conditions was 92% and 96%, respectively.

• Proceedings of the IEEK Conference
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• 대한전자공학회 1998년도 추계종합학술대회 논문집
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• pp.405-408
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• 1998

Generally, the principle function of simulator control loading system is to provide the pilot or student with the "feel" of the actual aircraft flight control systems during flight, taxing, and in malfunction. Flight control "feel" is the resistance felt by the pilot when moving a control stick or pedal, coupled with the amount of control surface deflection, and hence aircraft response, resulting from the input. Therefore, the control loading servo must be capable of performing to some general list of requirements derived from real aircraft control forces. In this paper, we deal with a $\mu-controller$ design for a control loading system of the flight simulator. For this, we derive a frequency response of the hydraulic system from the identification data and then design a controller using a $\mu-synthesis$ method. Under the same condition of simulation, $\mu-controller$ provides the superior performance than PID controller.than PID controller.