• The Korean Journal of Physiology and Pharmacology
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• 제2권6호
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• pp.705-714
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• 1998

Cerebral blood vessels relax when extracellular $K^+$ concentrations $([K^+])_e$ are elevated moderately $(2{\sim}15$ mM, $K^+-induced$ vasorelaxation). We have therefore studied the underlying mechanism for this $K^+-induced$ vasorelaxation in the isolated middle cerebral arteries (MCAs). The effects of ouabain and $Ba^{2+}\;on\;K^+-induced$ vasorelaxation were examined to determine the role of sodium pump and/or Ba-sensitive process (possibly, inward rectifier K current) in the mechanism. Mulvany myograph was used to study 24 rats, 18 rabbits, and 10 humans MCAs $(216{\pm}3\;{\mu}m,\;347{\pm}7\;{\mu}m,\;and\;597{\pm}39\;{\mu}m$ in diameter when stretched to a tension equivalent to 55 mmHg). High $K^+$ (125 mM) and $PGF_{2{\alpha}}\;(1{\sim}10\;{\mu}M)$ induced concentration-dependent contractions in all 3 species, while histamine $(10{\sim}50\;{\mu}M)$ evoked contraction only in the rabbits and induced relaxation in the rats and humans. Addition of $K^+\;(2{\sim}10\;{\mu}M)$ to the control solution induced vasorelaxations. These effects were inhibited by the pretreatment with both ouabain $(10\;{\mu}M)$ and $Ba^{2+}\;(0.1{\sim}0.3\;mM)$ in the rat, but only with ouabain $(10\;{\mu}M)$ in the rabbit and human. These results suggest that $K^+-induced$ vasorelaxation occurs via the stimulation of electrogenic Na pump in the rabbit and human MCAs, while in the rat MCAs via the activation of both Na pump and Ba-sensitive process.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2002년도 제9회 학술 발표회 프로그램과 논문초록
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• pp.9-11
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• 2002

Plasma membrane Na$^{＋}$-K$^{＋}$ ATPase (pump) is an essential component to maintain asymmetrical ion distribution across cell membrane. The Na$^{＋}$-K$^{＋}$ ATPase was discovered by Jens C. Skou in 1957 and since then physiological and biochemical properties of the enzyme have been extensively studied. Jens C. Skou was awarded the 1997 Nobel Prize in chemistry for his discovery of the Na $^{＋}$ - $K^{＋}$ ATPase.(omitted)

• Journal of Chest Surgery
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• 제48권3호
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• pp.206-209
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• 2015

Ascending aortic aneurysms are usually treated with graft replacement under cardiopulmonary bypass. However, if a candidate for off-pump coronary artery bypass grafting has an enlarged ascending aorta, surgeons may consider wrapping it without cardiopulmonary bypass. Here, we report a 78-year-old female who underwent successful wrapping of the ascending aorta concomitant with off-pump coronary artery bypass grafting, using a new wrapping technique that involves multiple bootstraps.

• The Korean Journal of Physiology
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• 제9권2호
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• pp.41-48
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• 1975

The failure of the action potential at the end-plate membrane to reach the sodium equilibrium potential is due to the stimulating action of acetylcholine on $Na^+-K^+$ pump. This action of acetylcholine causes an enormous increase in the $K^+$ transport rate. The quantitative amount of potassium ions in the inside of the end-plate membrane prevented the permeability of sodium ions during the depolarization phase of the action potential. It would favor the changes in the shape of action potential by acetylcholine which are always toward a fixed potential slightly below the zero line. The increased $Na^+-K^+$ pump activity by acetylcholine is responsible for the hypopolarization of membrane. This reduces the membrane resistance of the end-plate during transmitter activity.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.110.1-110.1
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• 2003

Fumonisins are specific inhibitors of ceramide synthase in sphingolipid metabolism. Sphingolipids are biologically active lipid mediators in cellular physiology and involved in cell signaling, growth, transformation, angiogenesis and differentiation. The objective of this study was to determine the effect of fumonisin B1 on $Na^+, \;K^+$-pump activity when fumonisin B1 was exposed to LLC-PK1 cells. Fumonisin B1 elevated free sphingoid bases and their 1-phosphates, while total complex sphingolipids were depleted at 20$\mu$M fumonisin B1 during the 3 day exposure. (omitted)

• 대한약리학회지
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• 제32권2호
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• pp.189-199
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• 1996

Myocardial ${\alpha}_1-adrenoceptors$ have been shown to mediate a biphaslc inotropic response that was characterized by a transient decline followed by a sustained increasing phase in guinea pig ventricular muscle. Recently one group reported that an ${\alpha}_1-adrenoceptors-induced$ intracellular $Na^+$ decrease is linked to fast $Na^+$ channel inhibition and another group reported that it is linked to $Na^+$-$K^+$ pump activation by ${\alpha}_{1b}-adrenoceptors$. But until now, its mechanism is not clear. Therefore, to see whether the $Na^+$channel or $Na^+-K^+$ pump is related to a decrease in intracellular $Na^+$ activity and/or the negative inotropic response, and which ${\alpha}_1-adrenoceptor$ subtype was involved in the decrease in intracellular $Na^+$activity by phenylephrine, we used conventional and sodium selective microelectrodes, and tension transducer to determine the effects of ${\alpha}_1-adrenergic$ stimulation on membrane potential, intracellular $Na^+$ activity, and twitch force in guinea pig ventricular muscles. $10^{-5}$ M Phenylephrine produced a slight hyperpolarization of the diastolic membrane potential, a decrease or increase in $a_N^i_a$, and a biphasic inotropic response. The negative inotropic response accompanied by a decrease in intracellular $Na^+$activity, whereas in muscles showing a remarkable positive inotropic response without initial negative inotropic effect was accompanied by an increase in intracellular $Na^+$ activity. The decrease in intracellular $Na^+$ activity was apparently inhibited by WB4101, an antagonist of the ${\alpha}_{1a}-adrenoceptors$. The decrease in intracellular $Na^+$ activity caused by phenylephrine was not abolished or reduced by a block of the fast $Na^+$ channels. $V_{max}$ also was not affected by phenylephrine. Phenylephrine produced an increase in intracellular $Na^+$ activity in the presence of a high concentration of extracellular $Ca^{2+}$ (in quiescent muscle) or phorbol dibutyrate, a protein kinase C activator(in beating muscle). These suggest that the ${\alpha}_{1a}-adrenoceptors-mediated$ decrease in intracellular $Na^+$ activity may be related to the protein kinase C.

• Journal of Chest Surgery
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• 제35권4호
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• pp.261-266
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• 2002

배경 및 목적; 심폐체외순환의 부작용을 피하기 위해 최근 들어 심폐체외순환 없이 시행하는 관상동맥우회로술(Off pump CABG)이 시도되고 있다. 이 연구는 Off pump CABG와 심폐체외순환하에서 시행하는 관상동맥우회로술(On Pump CABG) 의 수술 전 위험요소와 수술 후 결과를 비교하였다. 방법; 2001년 1월부터 2001년 7월까지 CABG를 시행 받았던 178명중에서 판막수술이나 심실절제술 등 동반 수술이 없었던 166명을 대상으로 하였다. 이 중 Off Pump CABG환자는 52명이었고 On Pump CABG환자가 114명이었으며, 이 환자들을 대상으로 수술전 위험인자와 관상동맥 질환의 정도 및 수술 후 결과를 비교하였다. 결과; 두 군간의 연령, 남녀 비, 수술전 당뇨, 고혈압, 흡연력, 고지질증, 가족력 등 위험요소에 대한 통계적인 유의성은 없었으며, 폐쇄성 폐 질환이나 말초 동맥혈관 협착증 및 뇌경색의 기왕력, 심근경색의 기왕력이나 흉통의 정도(Canadian Class),관상동맥 질환의 정도 및 심박출계수도 통계적인 차이를 보이지 않았다. 수술시간은 Off Pump CABG에서 통계적으로 유의하게 짧았고(234 $\pm$ 37 min vs 290 $\pm$ 48 min, p<0.001), 이 식편수는 On Pump CABG에서 유의하게 많았다(3.4 $\pm$ 0.9개 vs 2.6 $\pm$ 0.8개, p<0.001). 수술 후 사망은 없었으며, 수술 후 측정한 CK-MB는 Off Pump CABG에서 통계적으로 유의하게 낮았고(10.1 $\pm$ 13.5 IU/L vs 33.1 $\pm$ 18.2 lU/L, p<0.001) 호흡기 사용시간도 통계적으로 유의하게 낮았다(14.8 $\pm$ 3.5 hours vs 16.2 $\pm$ 4.9 hours, p=0.048). 그 외 24시간 출혈량, 출혈로 인한 재수술, 중환자실 입원 기간, 수술 후 심근경색증, 감염, 신부전증, 신경과적 합병증 및 수술 후 입원 기간 등 수술 후 결과와 유병율에는 두 군간의 통계적 유의성이 없었다. 결론; Off Pump CABG는 On Pump CABG에 비해 수술시간의 단축과 수술 후 심근 손상의 정도가 낮고, 호흡기 사용시간이 짧게 나타났으나 On Pump CABG에 비해 이식편수가 적었다. 대체로 Off Pump CABG는 On Pump CABG에 비해 수술 후 결과에서 약간의 장점을 보여주었으나 Off Pump CABG의 장점을 알아보기 위해서는 더 많은 연구가 있어야 할 것으로 생각된다.

• 한국방사선학회논문지
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• 제11권2호
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• pp.157-165
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• 2017

본 논문에서는 고에너지 엑스선(6MeV)을 조사한 세포막 모델에서 $K^+-Na^+$ pump 시스템의 능동적 전달특성에 대하여 연구하였다. 이 실험에 사용된 세포막 모델은 $Na^+$슬폰화 폴리스티렌-디비닐벤젠(polystyrene-divinylbenzene) 혼성 중합막을 사용하였다. 이온의 초기플럭스는 $H^+$이온 농도의 증가와 함께 증가하였다. 이 실험의 조건을 pH 1.5-5, 온도 $36.5^{\circ}C$로 하여 첫 번째, 방사선이 조사되지 않은 막에서 $K^+$의 초기플럭스는 $2.09{\times}10^{-4}-1.32{\times}10^{-3}mole/cm^2{\cdot}h$이고 $Na^+$의 초기플럭스는 $7.09{\times}10^{-4}-1.09{\times}10^{-3}mole/cm^2{\cdot}h$으로 나타내었다. 두 번째, 방사선이 조사된 막에서 $K^+$의 초기플럭스는 $21.0{\times}10^{-4}-16.7{\times}10^{-3}mole/cm^2{\cdot}h$이고 $Na^+$의 초기플럭스는 $62.0{\times}10^{-4}-20.6{\times}10^{-3}mole/cm^2{\cdot}h$으로 나타내었다. 막의 $K^+/Na^+$선택도는 약 1.10이다. 조사된 막의 pH의 추진력은 조사되지 않은 막보다 약 9-20배 정도 유의성 있게 증가하였다. 세포막모델에서 $K^+-Na^+$의 pump 시스템의 능동적 전달특성이 비정상적이기 때문에 세포장해가 세포에서 발현된다고 사료된다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.592-595
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• 2009

In recent years, geothermal heat pump (GHP) systems have become increasingly popular for heating and cooling in buildings. The Standing Column Well (SCW) method is one of the most efficient GHP system. Because it use groundwater for heat transfer material. In SCW systems, water is re-circulated between the well and the building (heat pump). It is only a short time since this method has been applied in domestic. So we have to refer to the developed countries' guides and manuals of SCW. In this paper, several design and construction points of SCW method are filed. We used real operation data of SCW system at Chong-Ju Univ. site for economical efficiency analysis. As a result, the payback period of Chong-Ju Univ. site is calculated at 7.23 years.

• Journal of Information Display
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• 제7권1호
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• pp.35-40
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• 2006

Organic light-emitting diode (OLED) display panel using the charge-pump (CP) pixel addressing scheme was fabricated, and the results show that it is applicable for information display. A CP-OLED panel with 64 ${\times}$ 64 pixels consisting of thin-film capacitors and amorphous silicon Schottky diodes was fabricated using conventional thin-film processes. The pixel drive circuit passes electrical current into the OLED cell during most of the frame period as in the thin-film transistor (TFT)-based active-matrix (AM) OLED displays. In this study, the panel was operated at a voltage level of below 4 V, and this operation voltage can be reduced by eliminating the overlap capacitance between the column bus line and the common electrode.