• 전기학회논문지P
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• 제59권2호
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• pp.191-196
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• 2010

The electricity distribution system in Korea is adopting a multi-grounding system. Protection of this distribution system against lightning is performed by installing overhead ground wires over the high voltage wires, and connecting the overhead ground wires to the ground every 200 m. The ground resistance in this system is limited not to exceed $50\Omega$ and overhead ground wire and neutral wire are multiple parallel lines. Although overhead ground wire and neutral wire are installed in different locations on the same pole, this circuit configuration has duplicated functions of providing a return path for unbalanced currents and protecting the distribution system against induced lightning. Therefore, the purpose of this study is to analyze the induced lightning shielding effect according to the neutral wire installation structure of a 22.9kV distribution line in order to present a new 22.9kV distribution line structure model and characteristics. This study calculated induced lightning voltage by performing numerical analysis when an overhead ground wire is present in the multi-grounding type 22.9kV distribution line structure, and calculated the induced lightning shielding effect based on this calculated induced lightning voltage. In addition, this study proposed and analyzed an improved distribution line model allowing the use of both overhead wire and neutral wire to be installed in the current distribution lines. The result of MATLAB simulation using the conditions applied by Yokoyama showed almost no difference between the induced lightning voltage developed in the current line and that developed in the proposed line. This signifies that shielding the induced lightning voltage through overhead wire makes no difference between current and proposed distribution line structures. That is, this study found that the ground resistance of the overhead wire had an effect on the induced lightning voltage, and that the induced lightning shielding effect of overhead wire is small.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1995년도 춘계학술대회
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• pp.92-92
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• 1995

It has been suggested that oxygen-derived free radicals have an important role in the pathophysiology of acute gastric ulceration induced by NSAIDs and ischemia-reperfusion. Taurine is hypothetized to exert its protective effect on NSAIDS-induced gastric injury by its antioxidant properties, Protect ive effect of taurine on indomethacin-induced gastric mucosal lesion and its protective mechanism were investigated. Intragastric administration of 25 mg/kg of indomethacin induced hemorrhagic lesions on the glandular stomach in rats, Pretreatment with 0.25 g/kg of taurine for 3 days significantly reduced the gastric lesion formation and Inhibited the elevation of lipid peroxide level In gastric mucosa. Both resting and FMLP-induced luminol-dependent chemiluminescence of rat peritoneal neutrophils increased immediately after treatment of indomethacin. 5-20mM of taurine inhibited chemiluminescence of neutrophils activated by indomethacin and/or FMLP. Human neutrophils (polymorphonuclear leukocytes) significantly adhered to confluent monolayer of human umbilical vein endothelial cells(HUVEC) after coincubation with aspirin or indomethacin. Also taurine prevented neutrophil adhesion induced by these drugs to HUVEC in dose-dependent manner. These results indicate that the protective effect of taurine against NSAIDS-induced gastric mucosal Injury is due to its antioxidant effect, which inhibits lipid peroxidation and neutrophil activation.

• 대한한방내과학회지
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• 제15권2호
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• pp.27-36
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• 1994

In order to investigate the effect of BODUOPAE-SAN(BOS), experiments were performed on analgesic effect induced by acetic acid, duration of hypnosis induced by pentobarbital-Na in mice and gastric ucler in Shay rats and indomethacin induced gastric ulcer, HCI-ethanol induced gastrci lesion in rats and gastric juice secretion in Shay rats. The results are as followings. 1. BOS showed significantly an analgesic effect induced by acetic acid. 2. BOS prolonged the duration of hypnosis induced by pentobarbital-Na in rats 3. BOS rised the spontaneous motility of isolatied ileum of mice temporarily. 4. BOS depressed the gastric motility of rats significantly. 5. BOS showed an anti-ulcer effect in Shay rats and indometacine-induced ulcer rats significantly. 6. BOS reduced the ulcer index of the HCl-ethanol induced gastric lesion in rats. 7. BOS reduced the gastric juice secretion in Shay rats. From above results think BOS is more effective in comparison to the OPAESAN alone on gastrointestinal disorder.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 1998년도 Advances in Ginseng Research - Proceedings of the 7th International Symposium on Ginseng -
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• pp.289-299
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• 1998

In this present study, we investigated the effects of red ginseng extract and its active constituents - Rbl , Re, Rgl on cycloheximide (CXM)-induced amnesia in the passive avoidance task in rats. Red ginseng water extract at 0.05-0.5 g/kg could improve CXM-induced amnesia in rats, Furthermore, the recovery effect of Rbl at 10 mghg administered 30 min before training trial from CXM-induced amnesia was better than those of Rbl administered other time before or after training trial. Rbl at 0.001-0.1 mghg could significantly improve CXM-induced amnesia and at 1 mghg completely augmented, but at 10 mghg its improving effect slightly weakened. Rgl and Re at 0.3-10 mghg could significantly improve CXM-induced amnesia and Rgl at 10 mg/kg completely avgmented. On the other hand, Rbl at 10 mghg could prolong the step through latencies in the training trial. These results suggest the beneficial effect of red ginseng extract on CXM-induced amnesia in rats could mainly due to the contribution of its active constituents - Rbl, Re, Rgl. The improving effect of Rbl on CXM-induced amnesia was best among the three active constituents. But the reduction in the improving effect of Rbl at 10 mg/kg might be due to the decrease in motor activity and attention to the passive avoidance task.

• The Korean Journal of Physiology and Pharmacology
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• 제1권6호
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• pp.797-808
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• 1997

Nitric oxide (NO) has been 3mown as a mediator of nonadrenergic, noncholinergic inhibitory neurotransmitter in intestinal smooth muscles. It has been suggested that NO donor such as sodium nitroprusside (SNP) produces relaxation of smooth muscle via activation of guanylate cyclase and elevation of cGMP levels. We have therefore investigated the effects of NO, using SNP, on muscle tension in the longitudinal smooth muscle of guinea-pig ileum. The possible role of cGMP was also investigated as well as the involvement of $K^+$ channel on SNP-induced inhibitory effect. The results are summarized as follows; high KCI-or CCh-activated contractions were inhibited by SNP in a concentration-dependent manner. 8-Br-cGMP also showed a similar effect in that of SNP TEA (1 mM) significantly reduced the SNP-induced inhibitory effect. SNP-induced effect was forther reduced by the presence of 10 mM TEA. On the other hand, 4-AP (0.1 mM), glibenclamide $(10\;{\mu}M)$ and apinain $(0.1\;{\mu}M)$ showed little effects on SNP-induced relaxation. Zaprinast significantly potentiated the SNP-induced inhibitory effect in all ranges. ODQ also significantly decreased the SNP-induced inhibitory effect. Pretreatment with CPA $(10\;{\mu}M)$ slightly reduced the SNP-induced inhibitory effect. From the above results, both effect mediated by NO and cGMP might be responsible for the activation of $Ca^{2+}$-activated $K^+$ channel by SNP in guinea-rig ileum. And this $K^+$ channel activation by SNP also contributes to the SNP-induced membrane hyperpolarization and relaxation.

• 대한본초학회지
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• 제26권3호
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• pp.75-82
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• 2011

Objectives : In this study, we evaluated the effect of Chungganhaeju-hwan(CGHJH) on hydrogen peroxide($H_2O_2$)-induced and ethanol(EtOH)-induced neuronal damage in vitro and in vivo, respectively. Methods:We carried out the anti-oxidant effects of CGHJH against hydrogen peroxide($H_2O_2$)-induced toxicity in HT22 and PC12 cells using thiazolyl blue tetrazolium bromide. Then, to investigate the protective effect on CGHJH against EtOH-induced memory impairment and hippocampal cell damage in male ICR mice, we performed novel object recognition test(NORT), and analysed the brain tissues after immunohistochemistry and western blotting. Results:CGHJH showed protective effect from $H_2O_2$-induced cell toxicity at doses of $1\sim100{\mu}g$/mL in both HT22 and PC12 cells. CGHJH had also recovery effect from EtOH-induced memory impairment in ICR mice from NORT and it protected hippocampal cells against EtOH toxicity in the result of cresyl violet and NeuN immunoreactivity. Conclusion : These results demonstrate that CGHJH has protective effect in neuronal cells against $H_2O_2$ and EtOH toxicities and this effect could be a main role of recovery effect on EtOH-induced memory loss.

• 대한수의학회지
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• 제30권3호
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• pp.283-286
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• 1990

The effects of nifedipne and verapamil were compared on carrageenan-induced paw edema in rats and the results are summarized as follows: Carrageenan induced severe acute paw edema within 30 minutes and the maximum effect was achieved around 4 hours after administration. The carrageenan-induced paw edema was prominantly reduced by pretreatments of indomethacin (2mg/kg, p.o.) and nifedipine (10 and 20mg/kg, i.p.), whereas verapamil had no effect on the carrageenan-induced paw edema. These results suggest that calcium antagonists, nifedipine and verapamil, have a different effect on the inflammatory response induced by carrageenan.

• 약학회지
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• 제45권1호
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• pp.93-100
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• 2001

Drug inetraction between of enalapril-induced angiotensin converting enzym) inhibitory effect and Ginkgo biloba Ext.-induced antioxidant action was evaluated in spontaneously hypertensive rats. Combination treatment of enalapril (20 mg/kg/day p.o.) and Ginkgo biloba Ext. (60 mg/kg/day, p.o.) for 6 weeks in drinking water to SHRs resulted the inhibition of ACE activity in lung tissue, angiotensin I-induced pressure response and plasma angiotensin II concentration as similar to enalapril alone treatment. But these effects were sustained after 1 week withdrawal of enalapril and Ginkgo biloba Ext. co-administeration. Also, coadministered group did not increase the concentration of bradykinin in lung tissue, which were different from enalapril alone treated group. Co-administration of enalapril and Ginkgo biloba Ext. inhibited the hemolysis induced by UV B type, even Ginkgo biloba Ext. alone treated group did not. These results suggested that Ginkgo biloba Ext. sustained ACE inhibitory effect and reduced the inhibitory effect of bradykinin inactivation induced by enalapril, meanwhile, enalapril increased the antioxidant effect of Ginkgo biloba Ext.

• 한방안이비인후피부과학회지
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• 제14권2호
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• pp.154-172
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• 2001

Major symptoms of al1ergic rhinitis are nasal obstruction, sneezing and watery rhinorrhea. Onpyetang has been used to treat for nasal obstruction, which is one of the symptoms of allergic rhinitis. This Experimental study was done to research effects of Onpyetang and transformed Onpyetang(Allii Radix is deducted from Onpyetang) on the anti-allergic effects. We have studied the vascular permeability response induced by serotonin and histamine, the contact dermatitis response induced by picryl chloride, the delayed type hypersensitivity response to SRC, the mice paw edema induced by carrageenin, the writhing syndrome induced by $0.7\%$ acetic acid, and the rectal temperature in febrile rats induced by yeast. The results were as follows : 1. In the vascular permeability response to intradermal serotonin and histamine. Onpyetang proved significant inhibitory effect(P<0.05, p<0.001) But transformed Onpyetang proved significant inhibitory effect only to histamine(P<0.05) 2. In the contact dermatitis response induced by picryl chloride, Onpyetang and transformed Onpyetang proved significant inhibitory effect.(P<0.05, P<0.05) 3. In the delayed type hypersensitivity response induced by SRC, Onpyetang and transformed Onpyetang proved significant inhibitory effect on mice paw edema.. (P<0.05, P<0.05) 4. In the delayed type hypersensitivity response induced by SRC, Onpyetang proved significant inhibitory effect to serum IgE.(P<0.01) But transformed Onpyetang proved insignificant inhibitory effect on serum Ig E. 5. In the mice paw edema induced by carrageenin, Onpyetang and transformed Onpyetang proved significant anti-inflammatory effect. (P<0.01, P<0.01) 6. In the writhing syndrome induced $0.7\%$ acetic acid, Onpyetang and transformed Onpyetang proved significant analgestic effect. (P<0.01, P<0.01) 7. In the rectal temperature in febrile rats induced by yeast, Onpyetang and transformed Onpyetang proved significant anti-pyretic effect.(P<0.001, P<0.01) according to this result Onpyetang was conclude to be effective on anti-allergic, anti-pyretic, anti-inflammatory and analgestic action. but transformed Onpyetang(Allii Radix is deducted from Onpyetang) was not effective on the vascular permeability response to intradermal serotonin and increasing Ig E of delayed type hypersensitivity response induced by SRC. In addition, transformed Onpyetang is not effective as Onpyetang. More study should be done about the role of Allii Radix.

• 보건의료산업학회지
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• 제6권3호
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• pp.219-229
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• 2012

In these days, the interest on medical industry is increasing around the world. This paper attempts to estimate the economic effects of the medical and measuring instrument industry through the Input-Output Analysis. Especially, 78*78 Sector Tables were used as the first analysis tool. So then, 79*79 Sector Tables adjusted were used for that industry. The main analysis tools of this study are comparing and analyzing backward and forward linkage effect, the induced effect of the self industry and other industries and the induced coefficients such as products, value-added, employee's pay, sales surplus, employment. According to the result of analysis, the medical and measuring instrument industry has great economic impacts which affects the major macroeconomic factors such as production and backward linkage effect. And the induced effects of the self medical and measuring instrument industry are significant compared to other industries in aspects of production, employee's pay and sales surplus.