移動荷重을 받는 橋梁의 振動制御

권호철,이인원 대한토목학회 1995 대한토목학회 학술발표회 논문집 Vol.1995 No.1

대기압 유전체 격벽 플라즈마를 이용한 폴리머 친수성 향상

권호철,김진우,김곤호 한국진공학회 2009 한국진공학회 학술발표회초록집 Vol.37 No.-

Usefulness of serum lactate as a predictor of successful discontinuation of continuous atropine infusion in patients with severe acute organophosphate poisoning

권호철,차용성,안교진,이윤석,김현 대한응급의학회 2018 Clinical and Experimental Emergency Medicine Vol.5 No.3

Objective In severe organophosphate (OP) poisoning, administration of atropine via continuous intravenous infusion is typically considered. To date, there have been no studies on predicting successful atropine discontinuation through plasma cholinesterase (PChE) and serum lactate levels, which are monitored during critical care in severe acute OP poisoning. Therefore, we retrospectively evaluated the usefulness of serum lactate and PChE as predictors of successful discontinuation of atropine infusion. Methods This retrospective observational study was performed on consecutive adult patients treated for severe acute OP poisoning between March 2011 and December 2016. We sequentially evaluated serum lactate and PChE levels on emergency department arrival and before a discontinuation trial of atropine infusion. Discontinuation of atropine intravenous infusion was attempted in patients after clearance of respiratory secretions and cessation of bronchoconstriction. Discontinuation of atropine infusion attempts were divided into successful and failed trials. Results A total of 95 trials were conducted in 62 patients. Serum lactate levels before trials were significantly different between patients with successful and failed trials. The area under the curve for prediction of successful atropine discontinuation using serum lactate levels before trial discontinuation were 0.742 (95% confidence interval, 0.638 to 0.846). PChE level was not significantly different between two groups. Conclusion Serum lactate levels before the discontinuation trial of atropine infusion served to predict successful discontinuation in severe acute OP poisoning.

전해질 내 방전 전극의 기포 막 두께에 따른 플라즈마 전력의 변화

윤성영,권호철,김곤호 한국진공학회 2010 한국진공학회 학술발표회초록집 Vol.38 No.-

Electron Density Monitoring By Using the V-I Phase Difference with a Circuit Model for a kHz Atmospheric-Pressure Dielectric Barrier Discharge

이승훈,권호철,김곤호 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.55 No.5

The electron density of a kHz atmospheric-pressure dielectric barrier discharge (APDBD) can be estimated from the V-I phase angle measurement by using the proposed equivalent circuit model. The model consists of plasma resistance, the capacitive reactance and the system impedance corresponding to the reactor capacitance and the power line impedance. The phase difference determined from the gap voltage (V) and the displacement current (I) in the equivalent circuit were applied to estimate the electron density in the reactor system. Since the V-I phase difference is a function of the ratio of the plasma resistance and reactance, the spatial averaged electron density can be analyzed The feasibility of the monitoring method was evaluated for 1 and 20 kHz APDBD plasmas using nitrogen gas. The obtained electron densities were in good agreement with the 1D simulation results, 105 ∼108cm−3 during a half cycle. The electron density of a kHz atmospheric-pressure dielectric barrier discharge (APDBD) can be estimated from the V-I phase angle measurement by using the proposed equivalent circuit model. The model consists of plasma resistance, the capacitive reactance and the system impedance corresponding to the reactor capacitance and the power line impedance. The phase difference determined from the gap voltage (V) and the displacement current (I) in the equivalent circuit were applied to estimate the electron density in the reactor system. Since the V-I phase difference is a function of the ratio of the plasma resistance and reactance, the spatial averaged electron density can be analyzed The feasibility of the monitoring method was evaluated for 1 and 20 kHz APDBD plasmas using nitrogen gas. The obtained electron densities were in good agreement with the 1D simulation results, 105 ∼108cm−3 during a half cycle.

척추 탈출 디스크 제거를 위한 미세 플라즈마 발생 장치 연구

김곤호,윤성영,권호철 한국진공학회 2010 한국진공학회 학술발표회초록집 Vol.38 No.-

Oxytocin의 자궁수축작용에 미치는 Diazepam의 영향

박윤기,이승호,권호철,하정희,이광윤,김원준 영남대학교 의과대학 1992 Yeungnam University Journal of Medicine Vol.9 No.2

Benzodiazepine계 약물들은 진정 최면제의 대표적인 약물로서, 중추신경계에서의 그 작용은 gamma amino butyric acid(GABA)수용체와 짝지워져 있는 benzodiazepine수용체를 통해서 나타나며 또한 뇌에 있는 synaptosome에서 전위 의존성 calcium channel을 통한 calcium의 섭취를 억제함으로써 진정작용 및 최면 작용이 나타난다. 이와 아울러 말초 장기에서도 benzodiazepine수용체와 GABA 수용체가 발견 되었는데 이들의 기능과 상호관계는 잘 알려져 있지 않다. 이에 본 실험에서는 benzodiazepine계통의 대표적인 약물이며 중추신경과 말초 장기에 동시에 작용하는 diazepam이 흰쥐 적출자궁의 자발 수축 및 diazepam유발 수축에 미치는 영향을 검색하고, 이러한 diazepam의 효과와 GABA수용체 및 calcium과의 상호관계를 검색함으로써 그 작용기전을 추구해 보기 위하여 다음과 같은 실험을 하였다. 난소를 제거한 후 estrogen(17 beta-estradiol : 500㎍/kg/day)을 4일 동안 전 처치한 흰쥐의 자궁을 적출하여 등적성 장력을 측정함으로써 그 수축력의 변화를 관찰하였다. Diazepam과 GABA수용체 효현제 및 그 봉쇄제들이 자궁절편의 자발 수축과 oxytocin 유발 수축에 미치는 영향을 검색하였고, 또 이들 약물의 작용에 관련된 calcium 동원기전에 대하여 관찰하여 다음과 같은 결과를 얻었다. Diazepam은 흰쥐 적출자궁의 자발수축 및 oxytocin 유발수축을 농도 의존적으로 억제하였다. GABA, GABA A 수용체 효현제인 muscimol, GABA A 수용체의 상경적 봉쇄제인 bicuculline, GABA A수용체의 비상경적 봉쇄제인 picrotoxin, GABA B수용체 효현제인 boclofen, 그리고 GABA B수용체 봉쇄제인 delta-aminovaleric acid는 흰쥐 적출 자궁의 자발 수축 및 oxytocin유발수축에 아무런 영향을 미치지 않았다. 자발 수축 및 oxytocin유발수축에 대한 diazepam의 억제 작용은 GABA수용체 효현제 및 봉쇄제의 영향을 받지 않았다. 그러나 bicuculline은 diazepam의 억제 작용에 상가적으로 작용하였는데, bicuculline의 이러한 작용은 muscimol에 의해서 길항되지 않았다. 정상 PSS 내에서 diazepam에 의해 억제되었던 자발수욱 및 oxytocin유발수축은 calcium의 첨가 및 calcium inophore인 A23187의 첨가로 일부 회복되었다. Calcium배제 용액내에서는 diazepam이 calcium첨가로 인한 수축력 회복을 방해하였으며 calcium inophore인 A23187에 의한 수축력 증가는 막지 못하였다. 또 세포외액에 calcium이 결핍된 상태에서는 oxytocin자체에 의한 수축을 방해하지 못하였으나 이어 첨가된 calcium에 의한 oxytocin유발 수축의 증가는 일부 억제하였다. 이상의 실험결과로 미루어 볼 때 diazepam은 자궁의 자발수축 및 oxytocin유발수축을 억제할 수 있으며, 이러한 작용은 GABA수용체 의존성이 아닌 세포외액의 calcium의 유입을 억제함으로써 나타나는 것으로 사료된다. This study was designed to investigate the effect of diazepam on the spontaneous contraction and oxytocin induced contraction of the isolated rat uterus. Female rat (Sprague-Dawley) pretreated with oophorectomy and 4 days administration of estrogen. weighing about 200 g, was sacrificed by cervical dislocation, and the uteruses were isolated. A longitudinal muscle strip was placed in temperature controlled (37℃) muscle chamber containing Locke's solution and myographied isometrically. Diazepam inhibited the spontaneous contraction and oxytocin induced contraction of the isolated rat uterus in a concentration-dependent manner. GABA, muscimol, a GABA A receptor agonist, bicuculline, a competitive GAGA A receptor antagonist, picrotoxin, a non competitive GABA A receptor antagonist, baclofen, a GABA B receptor agonist,and delta-aminovaleric acid, a GABA B receptor antagonist, did not affect on the spontaneous and oxytocin induced contraction of the isolated rat uterus. The inhibitory actions of diazepam on the spontaneous and oxytocin induced contraction were not affected by all the GABA receptor agonists and antagonists, but exceptionally potentiated by bicuculline. This potentiation-effect by bicuculline was not antagonized by muscimol. In normal calcium PSS, addition of calcium restored the spontaneous contraction preinhibited by diazepam and recovered the contractile of oxytocin preinhibited by diazepam. A23187, a calcium inophore, enhanced the restoration of both the spontaneous and oxytocin induced contraction by addition of calcium. In calcium-free PSS, diazepam suppressed the restoration of spontaneous motility by addition of calcium but allowed the recovery of spontaneous motility to a considerable extent. Diazepam could not inhibit some development of contractility by oxytocin in calcium-free PSS, but inhibited the increase in contractility by subsequent addition of calcium. These results suggest that the inhibitory action of diazepam on the rat uterine motility does not depend on or related to GABA receptors and that diazepam inhibits the extracellular calcium influx to suppress the spontaneous and oxytocin induced contractilities.

드럼세탁기의 Weight Balance 최적설계

조한기,노양환,권호철 (사)한국CDE학회 1996 한국CAD/CAM학회학회지 Vol.2 No.2

여수시관내 국도대체 우회도로(우두-종화) 건설공사 대안설계

이명재(Lee Myeong Jae),권호철(Kwon Ho Chul),조충영(Cho Chung Young),백종균(Baik Jong Gyun) 대한토목학회 2005 대한토목학회 학술대회 Vol.2005 No.10

Usefulness of delta neutrophil index for early prediction of overt disseminated intravascular coagulopathy in patients with venomous snakebite

차용성,이강현,이석정,권호철,이종욱,김형일,김오현,차경철,김현,황성오 대한응급의학회 2018 Clinical and Experimental Emergency Medicine Vol.5 No.2

Objective Clinically, consumptive coagulopathy, such as disseminated intravascular coagulopathy (DIC), is the most important among the common venomous snakebite complications owing to the serious hemorrhage risk associated with this condition. We evaluated the predictive value of the delta neutrophil index (DNI)—a new indicator for immature granulocytes—for DIC diagnosis. Methods This retrospective observational study consecutively assessed adult patients with venomous snakebites for over 51 months. Patients were categorized into the no DIC and DIC groups. DNI values were measured within 24 hours after snakebite. Results Thirty patients (26.3%) developed DIC. The DIC group had significantly higher median initial DNI than the no DIC group (0% vs. 0.2%, P<0.001). When the DIC group was divided into early and late groups (within and over 24 hours after snakebite, respectively), the DNI of the former was significantly higher than that of the latter and no DIC group. The late DIC group had significantly higher DNI than the no DIC group. Furthermore, DNI positively correlated with the DIC score (r=0.548, P<0.001). The initial DNI (odds ratio, 4.449; 95% confidence interval, 1.738 to 11.388; P=0.002) was an early DIC predictor. The area under the curve based on the initial DNI’s receiver operating characteristic curve was 0.724. Conclusion DNI values were significantly higher in the DIC group. Additionally, DNI was an early predictor of DIC development in patients with venomous snakebites in the emergency department.