• Biomolecules & Therapeutics
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• v.8 no.1
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• pp.53-63
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• 2000

This study was performed to elucited the mechanisms of the antidiuretic action by SKP-450, a $K^+$ channel opener, given into the vein, and of the diuretic action observed only in the ipsilateral kidney, when given into a renal artery, in dog. The antidiuretic action of SKP-450 was not affected by renal denervation or pretreatment with glibenclamide, a ATP-dependent $K^+$ channel blocker. The diuretic action of SKP-450 was inhibited by renal denervation or pretreatment with glibenclamide. SKP-450 given into carotid artery had little effect on renal function. These results suggest that the antidiuretic action of SKP-450 given into the vein is caused by some endogenous substances probably not related to $K^+$ channel, whereas the diuretic action of SKP-450 observed only in ipsilateral kidney, when given into a renal artery, is provoked through $K^+$ channel related to renal nerves.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.8 s.173
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• pp.100-107
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• 2005

The objective of the study is to improve the quality of wheel bearing hub by the rigid-plastic finite element analysis and the response surface methodology. The rigid-plastic finite element codes, AFDEX-2D and DEFORM-3D, were used to analyze the two-dimensional and three-dimensional forging processes, respectively. The response surface analysis is used to find the minimum underfill by the variation of design variables such as the height of billet after upsetting and punch angles of blocker dies. The metal flow of forged product shows good agreement with the results from 2D and 3D analysis. Also, the quality of the wheel bearing hub has been improved by the optimization of design variables and the machining time has been reduced by the machining allowance.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.3
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• pp.56-62
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• 2014

During the hot forging process, the most common cause of tool failure is wear. Tool wear results in the gradual loss of part tolerances, after which eventually the tool must be replaced or repaired. In order to maximize the lifetimes of forging tools, it is important to investigate the wear mechanisms of these tools. In this study, the hot forging of the outer race of an automotive constant-velocity joint was analyzed by a finite element method to investigate the wear distribution, especially the amount and location of the maximum expected wear damage, using Archard's wear model, which was modified considering the forging temperature. Forging analyses were carried out after modifying blocker forging tools based on established versions. The modified blocker tools resulted in an increase in the tool life up to 31% with a finisher punch.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2451-2452
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• 2010

• Korean Journal of Veterinary Service
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• v.18 no.2
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• pp.177-181
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• 1995

The effects of histamine were investigated on the uterine smooth muscle motility in the pig. The results were summarized as fellows : 1. Histamine caused the contraction of the porcine uterine smooth muscle and the contractile responses increased between the concetration of histamine $10^{-8}$ and $10^{-5}$ M with a dose-dependent manner. 2. The contractile response Induced by histamine ($10^{-6}$ M) was completely blocked by pretrevatment with $H_1$-histaminergic receptor blocker, pyrilamine($10^{-6}$ M) 3. The contractile response induced by histamine($10^{-6}$ M) was increased by pretreatment with $H_2$-histaminergic receptor blocker, cimetidine($10^{-6}$ M) From these results, it was concluded that the effects of uterine smooth muscle by histamine were the contraction mediated by $H_1$-histaminergic receptor and the relaxation mediated by $H_2$-histaminergic receptor in pig.

• Biomolecules & Therapeutics
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• v.19 no.1
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• pp.33-37
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• 2011

Decursin was purified from Angelica gigas Nakai, and its effects on the human Kv1.5 (hKv1.5) currents were recorded in mouse fibroblasts ($Ltk^-$ cells) by whole-cell patch-clamp technique. Decursin inhibited hKv1.5 current in a concentration-dependent manner, with an $IC_{50}$ value of $2.7\;{\mu}M$ at +60 mV. Decursin accelerated the inactivation kinetics of the hKv1.5 channel, and slowed the deactivation kinetics of the hKv1.5 current, resulting in a tail crossover phenomenon. Also, decursin inhibited the hKv1.5 current in a use-dependent manner. These results strongly suggest that decursin is a kind of open-channel blocker of the hKv1.5 channel.

• Korean Journal of Veterinary Research
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• v.56 no.4
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• pp.261-264
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• 2016

A nine-month-old Pomeranian dog with exercise intolerance and syncope was presented. The dog was depressed with grade 4 systolic murmur on cardiac auscultation. Based on cardiac examination, the dog was diagnosed with severe subaortic stenosis with involvement of the anterior mitral valve. ${\beta}-blocker$ administration was initiated and clinical signs were improved, but not fully resolved. Balloon valvuloplasty was performed and the dog survived for nearly one year without clinical sign and the cardiac troponin I level was normalized. This case describes successful management of severe subaortic stenosis in a small breed dog through balloon valvuloplasty.

• Biomolecules & Therapeutics
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• v.9 no.4
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• pp.237-243
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• 2001

This study was attempted to investigate the effects of cromakalim (CRK), $K^{+}$ channel opener, and glibenclamide (GLY), $K^{+}$ channel blocker, on intestinal function of rabbit. CRK supressed the tension and spontaneous movement of intestinal strips. CRK enhanced the tension and spontaneous movement of strips induced by acetylcholine. Also the inhibiting effect of dopamine was potentiated by CRK. GLY augmented the tension, but did not affect the spontaneous movement of strips. GLY inhibited tension and spontaneous movements in intestinal strips induced by acetylcholine, GLY blocked the dopamine-induced attenuation of tension, but not the decrease of spontaneous movements in intestinal strips. The present studies suggest that $K^{+}$ channel opening suppresses intestinal movements, whereas it's blockade enhances intestinal movements in rabbit.abbit.

• Journal of Chest Surgery
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• v.53 no.2
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• pp.86-88
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• 2020

A 39-year-old man presented to the department of emergency medicine in Seoul National University Hospital complaining of chest pain, heart palpitation, and headache. Upon arrival, a computed tomography scan showed a 7.0 cm×6.2 cm lesion with the typical features of a paraganglioma. The patient was treated with an alpha-blocker and a beta-blocker prior to surgical intervention. We removed the tumor successfully, and histopathologic findings indicated that the tumor was indeed a paraganglioma. Since intracardiac paraganglioma is a rare disease, we present this case together with a literature review.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 1999.03a
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• pp.243-248
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• 1999

There is substantial evidence that anatomical connections and functional interactions exist between vestibular and autonomic systems. Heart rate variability (HRV) including mean, standard deviation, coefficient of variation (CV), power spectrum was analyzed for evaluation of the physiological role of the vestibular system on control of heart rate in rabbits. In anesthetized rabbits, electrical stimulation of the vagus nerve decreased heart rate and decreased LF/HF by increasing HF. On the cervical sympathetic nerve increased heart rate and increased LF/HF by increasing LF. Atropine, cholinergic blocker, increased heart rate and increased LF/HF by reducing HF, and propranolol, ${\beta}$-adrenergic blocker, decreased heart rate and decreased LF/HF by reducing LF> In unanesthetized rabbits, stimulation of the vestibular system induced by rotation or caloric increased heart rate and increased LF/HF by increasing LF> Also electrical stimulation of the vestibular nerve produced the same of effects as rotation or caloric in anesthetized rabbits. These results suggest that Stimulation of the vestibular system increased heart rate not by inhibiting the parasympathetic nerve but by activating the sympathetic nerve.