• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.284-284
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• 2015

본 연구는 퍼클로레이트의 생물학적 환원 과정에 있어서 고농도의 염이 미생물에게 어떤 영향을 미치는지를 다양한 방법을 통해서 알아보고 적절한 모델링 접근을 통하여 최적 환원속도를 위한 반응조 조건 및 설계에 필요한 요소들을 도출하기 위해 수행되었다. 100mL 합성폐수를 포함하는 플라스크를 이용한 실험이 수행되었고, 일정 농도의 퍼클로레이트와 유일 탄소원으로 아세트산나트륨이 사용되었다. 염화나트륨 농도가 $7490{\mu}s/cm$에서 $23700{\mu}s/cm$까지 증가하는 동안 퍼클로레이트의 생물학적 환원 속도는 현저하게 감소하였으며, $32100{\mu}s/cm$ 이상의 염화나트륨 농도에서는 퍼클로레이트가 환원되지 않았다. 동일한 농도의 염화나트륨, 염화암모늄, 염산 및 황산이 포함된 하수에서는 퍼클로레이트의 환원속도가 모두 비슷하였다.

• The Korean Journal of Financial Studies
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• v.8 no.1
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• pp.21-54
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• 2002

본 논문은 1997년 말 우리나라의 외환위기이후 IMF에 의해 주도된 경제개혁방안 중 기업지배구조 개선과 관련하여 최근에 취해진 정부의 기업지배구조 개선을 위한 제반 정책을 평가하고 향후 바람직한 우리나라 기업의 지배구조 개선방안을 제시하는 것을 목적으로 한다. 외환위기 이전의 우리나라 기업지배구조는 여러 가지 척도로 평가했을 때 전반적으로 비효율적이었으며 특히 소액주주의 보호라는 측면에서는 전 세계적으로 최하위의 평가를 받았다. 따라서 최근에 취해진 제반 지배구조 개선 조치는 주로 소액주주의 권리를 강화하는데 초점을 맞추면서 선진국에서 시행하는 제반 제도를 집중적으로 도입한 것이었다. 그러나 기업지배구조 개선의 궁극적인 목적이 기업의 장기적인 경쟁력제고라고 할 때 최근의 조치는 경영자로 하여금 단기업적주의에 치중하고 우리 경제 발전의 원동력이 된 기업가정신을 저해할 가능성을 상당히 포함하고 있으므로 앞으로는 지식근로자들의 이해관계를 조정하고, 은행의 지배구조를 개선하여 은행의 감시기능을 제고하며 시장의 기능을 활성화하는 방향으로 정책이 전개되어야 할 것이다.

• Food Science and Industry
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• v.44 no.1
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• pp.63-68
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• 2011

Lactobacillus rhamnosus GG(ATCC 53013) 유산균은 현재 가장 많은 연구가 진행되고 있는 프로바이오틱 유산균들 중 하나이다. 이 유산균은 내산성, 내담즙성, 특유의 콜로니 모양, 장 정착성, 병원성 세균에 대한 경쟁적 저해작용 등의 선택기준을 통하여 분리되었고, 그 특성이 밝혀져 있다. 프로바이오틱 유산균의 선택기준이 진보하고 있지만, LGG 유산균은 아직도 매우 우수한 프로바이오틱 유산균이다. LGG 유산균은 그 유전적인 특성뿐만 아니라 설사예방, 아토피성 습진, 호흡기 감염에 대한 우수성이 임상시험을 통하여 입증되었다. 최근에는 임산부와 영아의 과체중에 대한 개선효과가 임상시험을 통해 증명되어 있다. 향후에는 특정 유산균 단독이나 과학적인 방법으로 선택된 프로바이오틱 유산균의 조합에 의한 유익성을 중심으로 복합 균주의 효과에 대한 새로운 증명이 기본적인 임상시험을 형성하게 될 것이다.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.57-57
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• 1995

1) 효소원의 조제 : 류마티스 관절염환자의 관절액 및 rat platelet PLA$_2$는 장등의 방법으로 조재하여 사용하였으며, 기질은 1-pal- (1-$^{14}$ C) linoleoyl PE로 하여 Dole 변법으로 효소활성을 측정하였다. 2) Histamine 유리반응 ; Rat복강으로부터 정제한 비만세포를 항원-항체 복합체로 자극하거나, $A_{23187}$등의 처리로 유리되는 histamine 을 methylation 시킨 후 유기용매법으로 추출한 후 scintillation counter로 측정하였다. 결과 : \circled1 천연물로부터 분리한 5종의 biflavonoid (amentoflavone 및 그 유도체)의 PLA$_2$ 저해 활성을 검토한 결과 거의 유사한 IC50 (약 3$\mu\textrm{m}$)을 나타내었다. \circled2 이들 중 amentoflavone은 염증성 PLA$_2$(Group II형 PLA$_2$)에 비교적 특이성을 나타내었다. 또한 제해양식은 비경쟁적 이면서 비가역적이였다. \circled3 비만세포에서 histamine 유리 억제반응은 자극제의 종류에 관계없이 억제작용을 나타내었으며, 기존에 임상적으로 사용되고 있는 Tranilast나 DSCG(disodium chromoglycate)에 비하여 10배 이상 강한 histamine 유리 억제작용을 나타내었다.다.

• Microbiology and Biotechnology Letters
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• v.41 no.1
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• pp.112-118
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• 2013

This study was performed to investigate the possible use of Eisenia bicyclis (EB) ethanol extract to inhibit activity against lipase. In tests, the lipase inhibitory activity of EB ethanol extract was noted as being 43, 27, and 24% at concentrations of 5, 2.5, and 1 mg/ml, respectively. Isolation was carried out by liquid and liquid extraction, silica-gel column chromatography, and HPLC. The results showed that the lipase inhibitory activity of the ethyl acetate (EA) fraction from EB ethanol extract exhibited the strongest lipase inhibitory activity with an $IC_{50}$ value of 1.31 mg/ml. The EA fraction was separated using silica-gel column chromatography and we obtained 22 sub-fractions. Amongst them, the EA1 fraction showed the highest lipase inhibitory activity with an $IC_{50}$ value of 0.54 mg/ml. Eight peaks were obtained from the EA1 fraction by HPLC. Fraction 5 also showed a strong lipase inhibitory activity with an $IC_{50}$ value of 0.37 mg/ml. The fraction 5 was identified as dieckol and the inhibition pattern analyzed from Lineweaver-Burk plots revealed a non-competitive inhibitor. These results suggest that EB has potential as a natural anti-obesity agent.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2008.04a
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• pp.5-20
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• 2008

GLP-1-based drugs (GLP-1 analogues and DPP IV inhibitors) and incretin mimetics are currently one of the most exciting classes of agents for type II diabetes. GLP-1, a gut peptide, is an incretin that potentiates glucose-dependent insulin release from the pancreas, slows GI-transit and stimulates the proliferation of beta-cells. DPP IV inhibitors act like incretins by inhibiting DPP IV which inactivates GLP-1. LC15-0133 is a competitive, reversible DPP IV inhibitor ($IC_{50}$ = 24 nM, Ki=0.247 nM) with excellent selectivity over other critical human proteases such as DPP II, DPP 8, elastase, trypsin. and urokinase. LC15-0133 showed long half-life and good bioavailability in rats and dogs. Inhibition of plasma DPP IV activity by LC15-0133 was kept more than 50% 24 hours after oral dosing in rats and dogs at 0.1 mg/kg and 0.02 mg/kg, respectively. The Minimum effective doses of LC15-0133 were 0.01 mg/kg for lowering blood glucose excursion during oral glucose tolerance test and 0.1 mg/kg for increasing glucose-induced GLP-1 response in C57BL/6 mice. Repeat oral administration of LC15-0133 for 1 month delayed the progression to diabetes and reduced HbA1c levels in a dose-dependent manner in Zucker Diabetic Fatty rats. In conclusion, LC15-0133 is a novel, potent, selective and orally active DPP IV inhibitor and showed an excellent blood glucose lowering effects in various animal models.

• Applied Biological Chemistry
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• v.10
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• pp.47-61
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• 1968

Sweetpotato infected by Soft-rot, Rhizopus nigricans, has been investigated for its biochemical changes. The results of the present experiment are summarized as follows: 1. From the Soft-rotted tuber, nineteen Ehrlich's positive substances and three fluorescent compounds which had not been found in a healthy tuber were detected with thin layer chromatography. 2, Ipomeamarone and umbelliferone, each of which are predominating substances among the Ehrlich's positive and fluorescent compounds, were isolated by silica gel column chromatography and studied for their identities. 3. Time course biosynthesis of the metabolites was studied and discussed for their possible biosynthetic pathways. 4. Among the metabolites, ipomeamarone and ipomeamarone-like substances have enzyme: inhibitive action against ${\alpha}$-amylase and probably other enzymes; the inhibition type was determined as the uncompetitive one. 5. Ipomeamarone obtained from soft-rotted sweetpotato was proved to have an uncoupling action as 2, 4-dinitrophenol.

• The Korean Journal of Food And Nutrition
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• v.28 no.1
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• pp.111-118
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• 2015

In summary, the rutin metabolite DHT significantly reduced EGF-induced neoplastic transformation in JB6 P+ cells. This inhibition was mediated mainly by blocking the Raf/MEK/ERK signaling pathway and subsequent suppression of AP-1 activities. DHT attenuated Raf-1 kinase activity by directly binding to Raf-1 in vitro and ex vivo. Taken together, these results suggest that Raf-1 may be a critical molecular target to suppress DHT-induced neoplastic transformation, which is mainly attributable to the chemopreventive potential of several foods containing rutin.

• Applied Biological Chemistry
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• v.40 no.2
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• pp.112-116
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• 1997

The enzymatic properties as well as its distribution in the cerebral region and subcellular organells were investigated for the neurosteroid acyltransferase from the bovine brain, which synthesize the fatty acid esters of the neurosteroids. The cerebellum region was the highest in NSAT activity while the cerebrum was the lowest with 50% of the cerebellar activity. The NSAT was found to be mainly localized in the microsomal fraction. The optimal temperature and pH were $40^{\circ}C$ and 4.9, respectively. When $^3H-DHEA$ was utilized as substrate, the $K_m$ and $V_{max}$ was $32.6\;{\mu}M$ and 4.86 nmole/mg protein/h, respectively. Under the same condition pregnenolone$({\Delta}^5P)$ was a competitive inhibitor with $K_i=22.8\;{\mu}M$ and testosterone was a uncompetitive inhibitor with $K_i=22.8\;{\mu}M$. This may suggest that the NSAT has a different conformation in the acylation of the ${\beta}-hydroxyl$ group at C-3 and C-17.

• Convergence Security Journal
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• v.14 no.1
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• pp.71-76
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• 2014

In modern society, a social economic change is brought about, because time space limitation regarded to be restrictive in times past was overcome owing to its rapid development on the basis of IT technology. The creation of new knowledge became the basis of competitiveness of nations and companies. As competition intensifies among nations and countries in relation to the development of core technology, companies make investment with placing much weight on the development of new technology, but on the other hand, technology leakage incident continuously occurs due to a lack of understanding to protect technology. This is the largest cause of impeding the competitiveness of nations and companies. And now, it is urgent to take security measures against this. Therefore, this paper analyzes institution and system weakness in the physical security area in the integrated security environment, and then identifies all problems about this, and proposes a plan for solving these.