• 대한토목학회논문집
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• 제5권2호
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• pp.83-90
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• 1985

본(本) 논문(論文)은 제체(堤體)의 중앙심벽형(中央心壁型) model을 제작(製作)해서 상류측(上流側) 각(各) 수위(水位)의 변화(變化)에 대한 침투유량(浸透流量)을 실험(實驗)을 통하여 구하고, 이 때의 침윤선형상(浸潤線形狀)과 Equipotential line에 대하여도 고찰(考察)한 것이다. 또한 실험(實驗)에서 얻은 자료(資料)를 FEM기법(技法)을 사용하여 구한 유선망(流線網)의 각요소별(各要素別) Flow-rate에 대한 유속(流速)과 침투유량(浸透流量)을 실험치(實驗値)와 근사리론공식(近似理論公式)에서 산출(算出)된 값과 비교검토(比較檢討)하였다. 침투수량(浸透水量)은 고수위시(高水位時)에서는 실험치(實驗値)보다 FEM 값이 적게 나타났으며, 저수위시(低水位時)에는 거의 비슷한 값이었다. 그리고, 유선망(流線網)이 형성(形成)된 각(各) 요소별(要素別) Flow-rate 는 X, Z 축(軸)은 수위변화(水位變化)가 있어 흐름에 따른 유속(流速)이 크나 Y 축(軸)의 유속(流速)은 무시할 수 있을 정도의 적은 값이었다.

• 동의생리병리학회지
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• 제18권2호
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• pp.490-495
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• 2004

Brain cells produce cytokines and chemokines during the inflammatory process of many neuronal diseases both in animal models and in patients. Inflammatory cytokines are the main responsible for the onset of inflammatory cascade. During the past decade, a growing corpus of evidence has indicated an important role of these cytokines in the development of brain damage. ZhenganXifeng-tang (ZGXFT) is a Korean herbal prescription, which has been successfully applied for the treatment of various neuronal diseases. However, its effect in experimental models remains unknown. Astrocytes are predominant neuroglial cells of the central nervous system and are actively involved in cytokine-mediated events in inflammatory disease. An inflammatory response associated with β-amyloid (Aβ) and interleukin (IL)-1β is responsible for the pathology of inflammation disease. To investigate the biological effect of ZGXFT, the author examined cytotoxicity, effect of cytokines (IL-6 and IL-8) secretion and expression of cyclooxygenase-2 (COX-2) on human astrocytoma cell line U373MG stimulated with IL-1β plus M fragment 25-35 (Aβ [25-35]). ZGXFT by itself had no effect on cell viability on human astrocytoma cells. The secretion of IL-6 and IL-8 was inhibited by pre-treatment with ZGXFT in human astrocytoma cells. In addition, the expression of COX-2 was induced by IL-1β plus AB[25-35] and was partially inhibited by treatment with ZGXFT. The author demonstrates the regulatory effects of inflammatory reactions by ZGXFT in human astrocytes for the first time and suggest the anti-inflammatory effect of ZGXFT may reduce and delay pathologic events of inflammatory disease.

• Archives of Plastic Surgery
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• 제33권5호
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• pp.541-545
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• 2006

Purpose: There are many methods for the reconstruction of the facial defect after an excision of a skin cancer; such as skin graft, local flap, free flap, etc... Skin graft has its' limitations; it could remain in different color with in regards of the recipient to donor, with an unfavorable scar. Free flap can lead to big donor site morbidity with long operation time and uncontrolled scar as a disadvantage factor. Compared to the prior, local flap offers several merits; sufficient blood supply, good tissue quality and short operation time. We revised 'V-Y-S flap' for the facial defect, which proved to have favorable outcomes. Methods: Total 7 V-Y-S flaps were performed to patients with skin cancers(six squamous cell carcinoma and one basal cell carcinoma). Two of these flaps were combined with composite grafts, one with full thickness skin graft. Six patients were female and one male. The average diameter of defects after excision was 2.3 cm. The follow-up period was 18 months maximally. Results: We treated seven facial skin cancers with 'V-Y-S flap'. There were no flap necrosis, cancer recurrence and scar contracture as a result. Furthermore, this method also offers a favorable central scar line that is parallel to the nasolabial fold and the nasojugal groove, especially in the nasolabial area and superomedial side of the cheek. With this method, we could cover a maximum diameter of 4cm facial defect. Conclusion: In conclusion, it is suggested that V-Y-S flap is a useful method to cover facial defects after the excision of a skin cancer.

• 한국실내디자인학회논문집
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• 제18권2호
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• pp.50-60
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• 2009

The change of idea about overall politics, society, technology, and culture in 20th century led to the change of kitchen which is the central space of household affairs as well. Frankfurt kitchen of Margarete Schuette Lihotzky which was introduced for the first time at Germany International Trade Exhibition in 1927 functionally designed small space of $6.5m^2$ with considering move-line and convenience. This is the beginning of kitchen type which has built-in sink and cupboard that is regarded as an universal option these days, and this has extensively been applied to kitchen system throughout the world after the repetitive development in America, Sweden and Switzerland. And improved kitchen of Park Gil-Yong which was influenced by rationalism introduced from the house improvement campaign and the opening of a port which were progressed in Korea in $1919{\sim}1930$ is the first stand-up kitchen which improved the inefficiency of Korean conventional kitchen. The purpose of this study is to understand the change aspect of kitchen through the rationalization in each country by comparing the introduction background of the times, change of space for residence and kitchen, and the characteristics of kitchen plan which had influence at the turning point on the kitchen in Korea, Europe on the side of efficiency at the same period, take into consideration of our residing-culture which has rapidly been changed between tradition and modernity, and to see the direction of kitchen design which copes with the unique residential environment.

• Journal of Nutrition and Health
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• 제49권2호
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• pp.72-79
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• 2016

Purpose: The initiation of mandatory folic acid fortification using pteroylmonoglutamic acid (PteGlu) has reduced the rate of congenital malformations. However, it also appears to be responsible for several adverse effects, including increased cancer incidence. This may be related to physicho-chemical characteristics of PteGlu. This study examines the potential effect of high concentrations of PteGlu on a population subjected to mandatory folic acid fortification using an in vitro model. Methods: Caco-2 (colorectal cancer) and MCF7 (breast cancer) cell lines were cultured at 6 different PteGlu concentrations (0, 0.1, 1, 50, 250, and $500{\mu}g/ml$) for 6 days. Cell growth was determined using thiazolyl blue tetrazolium bromide assay. The genotype of dihydrofolate reductase 19bp deletion/insertion (DHFR 19-del) was also scored in cell lines using a restriction fragment length polymorphism technique to examine whether genetic variations may factor in cell proliferation. Results: PteGlu exhibited differential growth promoting properties between cell lines. Caco-2 cells did not show a significant growth difference at low concentrations compared to control, however, at higher concentrations, the growth showed a contrasting trend in the early experimental period, while MCF7 showed enhanced cell growth at all concentrations. The DHFR 19-del genotype differed in the two cell lines. Conclusions: Altered response to PteGlu by Caco-2 and MCF7 may reflect a tissue specific disease aetiology or genotype specific differential enzyme activity, for example by DHFR, to critical levels of PteGlu. As folic acid fortification is a blanket intervention, and DHFR and other enzyme activities vary between individuals, PteGlu intake may have an as yet undefined effect on health. These findings may be relevant when considering mandatory folic acid fortification for disease prevention.

• 정신신체의학
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• 제7권2호
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• pp.274-280
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• 1999

중추신경계와 말초신경계의 손상으로 인한 다양한 기전에 의해서 신경병성 통증이 생길 수 있다. 특정한 질병과 관련된 기전에 의해서 생기는 경우는 거의 없고, 진단과는 상관없이 한 환자에서 여러 가지 기전이 동시에 관여하여 생긴다. 신경병성 통증은 신경학적 검사와 환자의 문진으로부터 쉽게 진단할 수 있으나 치료는 아직 만족할 만하지 못하다. 신경병성 통증의 치료가 어렵다 하더라도 의사가 치료시 문제점을 완전히 이해하고 있다면 적절한 치료에 도달될 수 있을 것이다. 적절한 약물의 선택은 환자마다 효과가 있는 약제, 용량, 혈중농도 등이 각기 다르기 때문에 치료의 시도와 실패의 반복을 통해서 얻어질 수 있다. 효과가 있다고 알려진 각 약물들의 적절한 치료연구는 신경병성 통증의 약물치료에 있어 핵심일 것이다. 삼환계 항우울제는 일차약물로 알려져 있고 이에 대한 효과가 만족스럽지 못할 경우에는 항경련제, 국소마취성 항부정맥제제, clonidine, 마약성 진통제, 국소도포제 순으로 사용해 볼 수 있다. Venlafaxine, nefazodone 같은 항우울제가 최근에 삼환계 항우울제 보다 부작용이 적고 비슷한 효과가 있으며, 항경련제인 gabapentine도 효과있는 약물로 널리 사용되고 있다.

• The Korean Journal of Physiology and Pharmacology
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• 제11권2호
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• pp.37-43
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• 2007

Adenosine has been reported to provide cytoprotection in the central nervous systems as well as myocardium by activating cell surface adenosine receptors. However, the exact target and mechanism of its action still remain controversial. The present study was performed to examine whether adenosine has a protective effect against $A{\beta}$-induced injury in neuroglial cells. The astrocyte-derived human neuroglioma cell line, A172 cells, and $A{\beta}_{25{\sim}35}$ were employed to produce an experimental $A{\beta}$-induced glial cell injury model. Adenosine significantly prevented $A{\beta}$-induced apoptotic cell death. Studies using various nucleotide receptor agonists and antagonists suggested that the protection was mediated by $A_1$ receptors. Adenosine attenuated $A{\beta}$-induced impairment in mitochondrial functional integrity as estimated by cellular ATP level and MTT reduction ability. In addition, adenosine prevented $A{\beta}$-induced mitochondrial permeability transition, release of cytochrome c into cytosol and subsequent activation of caspase-9. The protective effect of adenosine disappeared when cells were pretreated with 5-hydroxydecanoate, a selective blocker of the mitochondrial ATP-sensitive $K^+$ channel. In conclusion, therefore we suggest that adenosine exerts protective effect against $A{\beta}$-induced cell death of A172 cells, and that the underlying mechanism of the protection may be attributed to preservation of mitochonarial functional integrity through opening of the mitochondrial ATP-sensitive $K^+$ channels.

• 대한방사선기술학회지:방사선기술과학
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• 제22권2호
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• pp.27-32
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• 1999

Cochlear implant poses a contraindication to the magnetic resonance imaging(MRI) process, because MRI generates artifacts, inducing an electrical current and causing device magnetization. CT is relatively expensive and the metal electrodes scatter the image. Post-implantation radiological studies using anterior-posterior transorbital, submental-vertex and lateral views, the intracochlear electrodes are not well displayed. Therefore, the authors developed a special view, which we call the cochlear view. The patient is sitting in front of a vertical device. Then the midsagittal plane is adjusted to form an angle of $15^{\circ},\;30^{\circ}$, and $45^{\circ}$ with the film. The flexion of the neck is adjusted to make the infraorbitomeatal line(IOML) is parallel with the transverse axis of the film. The central ray is directed to exit from the skull at point which is 3.0 cm anterior and 2.0 cm superior to the EAM(external auditory meatus). Results have shown that single radiography of the cochlear view provides sufficient information to demonstrate the position of the electrodes array and the depth of insertion in cochlear. Radiography of the cochlear view in angle of $45^{\circ}$ is an excellent image. The cochlear view gives the greatest amount of medical information with the least radiation and lowest medical cost. It can be widely used in all cochlear implant clinics.

• Animal cells and systems
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• 제9권2호
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• pp.101-105
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• 2005

[ ${\beta}ig-h3$ ] is a secretory protein that is induced by $TGF-{\beta}$ and implicated in various disease conditions including fibrosis. We have previously reported that ${\beta}ig-h3$ expression is implicated in astrocyte response to brain injury. In this study, we further investigated potential roles of ${\beta}ig-h3$ protein in the injured central nervous system (CNS). We specifically assessed whether the treatment of microglial cells with ${\beta}ig-h3$ can regulate microglial activity. Microglial cells are the prime effector cells in CNS immune and inflammatory responses. When activated, they produce a number of inflammatory mediators, which can promote neuronal injury. We prepared conditioned medium from the stable CHO cell line transfected with human ${\beta}ig-h3$ cDNA. We then examined the effects of the conditioned medium on the LPS- or $IFN-{\gamma}-mediated$ induction of proinflammatory molecules in microglial cells. Preincubation with the conditioned medium significantly attenuated LPS-mediated upregulation of $TNF-{\alpha},\;IL-1{\beta}$, iNOS and COX-2 mRNA expression in BV2 murine microglial cells. It also reduced $IFN-{\gamma}-mediated$ upregulation of $TNF-{\alpha}$ and COX-2 mRNA expression but not iNOS mRNA expression. Assays of nitric oxide release correlated with the mRNA data, which showed selective inhibition of LPS-mediated nitric oxide production. Although the regulatory mechanisms need to be further investigated, these results suggest that astrocyte-derived ${\beta}ig-h3$ may contribute to protection of the CNS from immune-mediated damage via controlling microglial inflammatory responses.

• 천문학회보
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• 제39권2호
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• pp.74.1-74.1
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• 2014

We study a wraping instability of a geometrically thin, non-self-gravitating disk surrounding binary supermassive black holes on a circular orbit. Such a circumbinay disk is subject to not only tidal torques due Line 8 to the binary gravitational potential but also radiative rorques due to radiation emitted from each accretion disk. We find tat a circumbinary disk initially aligned with the binary orbital plane is unstable to radiation-driven warping beyond the marginally stable warping radius, which is sensitive to both the ratio of vertical to horizontal shear viscosities and the mass-to-energy conversion efficiency. As expected, the tidal torques give no contribution to the growth of warping modes but tend to align the circumbinary disk with the orbital plane. Since the tidal torques can suppress the warping modes in the inner part of circumbinary disk, the circumbinaary disk starts to be warped at the radii larger than the marginally stable warping radius. If the warping radius is of the order of 0.1 pc, a resultant semi-major axis is estimated to be of the order of 10-2 pc to 10-4 pc for 107 Msun black hole. We also discuss the posibility that the central objects of observed warped maser disks in active galactic nuclei are binary supermassive black holes with a triple disk: two accretion disks around the individual black holes and one circumbinary disk surrounding them.