• The Korean Journal of Physiology and Pharmacology
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• v.10 no.4
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• pp.181-186
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• 2006

This study was undertaken to evaluate whether peroxisome proliferator-activated-receptor-gamma $(PPAR-{\gamma})$ agonist-rosiglitazone (ROSI) induces postischemic functional recovery in Langendorf heart model. Hearts isolated from normal rats were subjected to 20 min of normoxia or 25 min zero-flow ischemia followed by 50 min reperfusion. In this acute protocol, ROSI $(20\;{\mu}g/ml)$ administered 10 min before ischemia had no effect on hemodynamic cardiac function, but had protective effect on lipid peroxidation in in vitro experiments. In chronic protocol in which ROSI was given by daily gavage (4 mg/kg) for three consecutive days, ROSI could not prevent the hemodynamic alteration on cardiac performance, but has protective effect on the activity of superoxide dismutase (SOD). There was no significant difference in the contents of reduced glutathione (GSH) and catalase activity between ischemia-reperfusion (IR) and ROSI treated IR hearts. Although ROSI had no effect on hemodynamic factor, it had effect on antioxidant activity. Our results indicate that ROSI provides partial beneficial effects by inhibiting lipid peroxidation and/or recovering normal level of SOD activity in the ischemic reperfused heart.

• Preventive Nutrition and Food Science
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• v.18 no.1
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• pp.38-44
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• 2013

The protective effect of Polyopes lancifolia extract on high glucose-induced oxidative stress was investigated using human umbilical vein endothelial cells (HUVECs). High concentration of glucose (30 mM) treatment induced HUVECs cell death, but Polyopes lancifolia extract, at concentrations of 25, 50, and $100{\mu}g/mL$, protected cells from high glucose-induced damage. Furthermore, thiobarbituric acid reactive substances, intracellular reactive oxygen species, and nitric oxide levels increased by high glucose treatment were effectively decreased by treatment with Polyopes lancifolia extract in a dose-dependent manner. Also, Polyopes lancifolia extract treatment reduced the overexpressions of inducible nitric oxide synthase, cyclooxygenase-2, and nuclear factor-kappa B proteins activation that was induced by high glucose in HUVECs. These results indicate that Polyopes lancifolia extract is a potential therapeutic material that will reduce the damage caused by high glucose-induced-oxidative stress associated with diabetes.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.760-763
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• 2003

We have investigated the electro-optical characteristics of image sticking in AC PDP. Although Image sticking is one of major factors to determine display quality in AC PDP, so far, it has not being reported why it is occurred and how we can prevent it. In this experiment, we have analyzed the effect of MgO protective layer and phosphor on the image sticking and we have measured the difference of firing voltage, brightness and discharge current between sticking image and normal image in AC PDP. As a result, Phosphor degradation is a more major factor than MgO protective layer and the firing voltage of gas discharge in sticking image is higher than that of normal discharge.

• Journal of Ginseng Research
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• v.34 no.2
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• pp.145-149
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• 2010

This study investigated the antioxidant effects of ginseng coffee in L6 muscle cells. Ginseng coffee was prepared by coating and digesting coffee beans with ginseng concentrate. The ginseng coffee water extract potently protected against hydrogen peroxide-induced L6 cell death and adenosine triphosphate reduction in a dose-dependent manner; in fact, these cytoprotective effects were significantly greater than those of normal coffee. However, ginseng coffee did not exhibit significant radical scavenging or catalase-like activity. These results suggest that ginseng coffee might act as a cytoprotective agent in muscles, but that the protective effects are not due to a direct radical-reduction property but rather to another intracellular signaling factor.

• The Journal of Korean Medicine
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• v.21 no.1
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• pp.91-98
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• 2000

The water extract of Seongpungtang(SPT) has commonly been used for treatment of ischemic brain damage in Oriental traditional medicine. However, little is known about the mechanism by which the water extract of SPT rescues brain cells from ischemic damage. To elucidate the protective mechanism of ischemic induced cytotoxicity, the regulation of Lipopolysaccharide (LPS) and PMA (phobol-12-myristate-13-acetate) induced iNOS expression in microglial cells was investigated. LPS and PMA treatment for 48 hr in microglial cells markedly induced nitric oxide (NO), but treatment of the cells with the water extract of SPT decreased nitrite formation. In addition, LPS and PMA treatment for 48 hr induced severe cell death in microglial cells. However treatment of the cells with the water extract of SPT did not induce significant changes compared to the control cells. Furthermore, NO production was markedly decreased by treatment of nuclear factor kappa B(NF-kB) inhibitor, pyrrolidine dithiocarbamate(PDTC). According to the above results, it is suggested that the protective effects of the water extract of SPT against ischemic brain damage may be mediated by regulation of iNOS during ischemic condition.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.9
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• pp.527-532
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• 2000

The performance of ac plasma display panels (PDP) is influenced strongly by the surface glow discharge characteristics on the MgO thin films. This paper deals with the surface glow discharge characteristics and some physical properties of MgO thin films prepared by reactive RF planar unbalanced magnetron sputtering in connection with ac PDP. The samples prepared with dc bias voltage of -10V showed lower discharge voltage and lower erosion rate byion bombardment than those samples prepared by conventional magnetron sputtering or E-beam evaporation. The main factor that improves the discharge characteristics by bias voltage is considered to be due to the morphology changes or crystal structure of the MgO thin film by ion bombardement during deposition process.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.9
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• pp.1141-1145
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• 2018

Generally, in nuclear plants, distance relay (21R) has adapting to protect and to operate main protective of transmission lines and backup protective of main generator. Operation of 21R was required and based on exactly accurate calculation and criteria. But presently method of 21R setting has applied according to protection devices operation guide of KPX, excepting IEEE and ISA standards, which have a difference review directions, consider parameters and devices, also consideration factors were affected to relay operations by uncertain guides. therefore this paper proposed new protection relay setting method and unvague criteria from IEEE 741 and ANSI/ISA 67.04.01, and reviewed a different results through numerical calculation results for methods and criteria including previous and established 21r setting by IEEE, ANSI/ISA Technical standards.

• Korean Journal of Child Studies
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• v.26 no.1
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• pp.329-345
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• 2005

Gender and intelligence of children, parenting practices and socioeconomic status of parents were studied to investigate whether they functioned as protective factors for resilient children. Total of 556 children of 12 years of age were contacted for the study. Teachers were asked to rate the children's interpersonal competence. Children reported their experience of stressful life events on a checklist. Based on the competence scores and the experience of stressful life events, 107 children were classified into adaptive, resilient, and maladaptive group. IQ scores were assessed using an intelligence test for the 107 children. Mothers reported their parenting practices and their socioeconomic status through a questionnaire. Descriptive statistics, chi-squares, t-tests, and one-way ANOVAs were performed to analyze the data. There was no difference in their experience of stressful life events between boys and girls. Girls were rated as being more competent by their teachers. There were more girls in the adaptive and the resilient group and more boys in the maladaptive group. Children in adaptive and the resilient group had higher intelligence scores than the maladaptive group. Mothers of resilient children replied as being warm and acceptive and more refusing and controlling than mothers of the adaptive children Group differences in socioeconomic status of the family were not found. Thus, being a girl and having higher IQ scores were the protective factors for the resilient children.

• Korean Journal of Social Welfare Studies
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• no.37
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• pp.399-427
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• 2008

The purpose of this study is to examine the moderating effects of protective factors on the relations between deviant peer's influences and delinquent behaviors in adolescence. To investigate the moderating effects, simple slope and region of significance test based on multiple linear regression(MLR) model were used. This study used data from wave 1-2(2003-2004) of the Korea Youth Panel Survey(KYPS). Results showed that for female adolescents, self-esteem, parent monitoring, and attachment to parent moderated the link between best friend's deviancy and delinquent behaviors. For male adolescents, however, best friend's deviancy and protective factors didn't show any significant moderating effects. These results help clarify the conditions under which exposure to deviant best friends can influence delinquent behaviors in adolescence. Practice and policy implications as well as further research topic were discussed to aid the search for highly effective preventive and treatment interventions.

• The Korea Journal of Herbology
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• v.37 no.4
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• pp.1-8
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• 2022

Objectives : Dioscorea batas Decaisne (DB) has been known to be good for the digestive system on Eastern Asia. However, the protective effect of DB on acute pancreatitis (AP) has not been studied. In this study, we tried to investigate the protective effect of DB water extract on caerulein-induced AP. Methods : To measure the protective effect of DB on AP, Mice were injected with cholecystokinin analogue caerulein (50 ㎍/kg) hourly for 6 times. DB water extract (200 or 400 mg/kg) or saline (control group) was administered orally 1 h before the first injection of caerulein. The mice were sacrificed at 6 h after the last injection of caerulein. The pancreas tissues and serum samples were immediately taken for further analysis. Results : Administration of DB water extract showed the inhibitory effect on the increase of pancreas weight/body weight ratio, pancreatic histological damage. And the rise of serum lipase level was significantly reduced in DB water extract treatment group during AP in mice. However administration of DB water extract did not show significant reduction in serum amylase level. Also, mRNA levels of pro-inflammatory cytokines Interleukin (IL)-6 and Tumor necrosis factor (TNF)-𝛼 but not IL-1𝛽 were inhibited by administration of DB water extract. Conclusions : Taken together, we found that administration of DB water extract ameliorates the severity of caerulein-induced AP, which suggests the potential to be an effective treatment on AP.