• 제목/요약/키워드: Early injection

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사염화탄소 투여가 Dimethylnitrosamine의 급성중독 간세포의 구조에 미치는 영향 (Effects of Carbon Tetrachloride on Structures in Hepatocytes Following DMN Induced Hepatotoxicity)

  • 강영천;남혜주;김동석;최원희;이태숙
    • Journal of Yeungnam Medical Science
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    • 제8권2호
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    • pp.84-94
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    • 1991
  • 간에 급성 출혈성 괴사를 일으키는 dimethylnitrosamine(DMN)의 간 독작용이 과량의 사염화탄소로 전처치시 어떤 영향을 받는 가를 관찰하기 위해 먼저 DMN을 쥐의 복강내에 주입하였다. 또 사염화탄소 전처치에 의한 영향을 조사하기 위해 사염화탄소 투여 후 DMN을 투여하고 간조직을 적출하여 광학 현미경 및 전자 현미경으로 관찰하였다. 광학 현미경하에서 DMN 단독 투여시 12시간부터 간 소엽중심부에 심한 출혈성 괴사가 나타나서 120시간까지 지속되었다. 과량의 사염화탄소로 전처치시 초기부터 광범위한 괴사가 나타났으나 24시간부터는 활발한 재생성변화가 나타나서 120시간에는 거의 정상으로 회복되어서 괴사의 정도는 DMN 단독 투여군과 유사하고 회복되는 시간은 단독 투여군보다 더 빨랐다. 전자 현미경하에서 DMN 단독 투여시 초기 변화는 주로 과립성 내형질막의 분열로 나타났고, 사염화탄소 단독 투여시는 내형질막의 덩어리 형성과 수포성 팽창으로 나타났다. 사염화탄소 전처치 후 DMN 투여시 초기에 나타난 변화는 그 양상이 사염화탄소 단독 투여시와 유사했지만 정도가 더 심했다. 이상의 결과에서 DMN의 급성중독 효과는 과량의 사염화탄소로 전처치한 경우에 재생이 더 빨리 이루어지는 것으로 보아 사염화탄소가 DMN에 대해 방어적인 작용을 하는 것으로 추측된다.

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Gene Transfer and Transient Expression of Foreign DNA in Limanda Yokohamae

  • Yoon, Yoon-Kwon
    • 한국양식학회지
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    • 제12권4호
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    • pp.275-281
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    • 1999
  • The utility of RSV-LTR and carp beta-actin promoters was evaluated in a marine flatfish species, Limanda Yokohamae by examining successful expression of transgenic DNA in muscles (transfected by direct injection) and in early embryos (transformed by lipofected sperm). The expressed pattern of injected DNA in skeletal muscles was dependent on the DNA amount injected. The activity reached to maximal level at 48 hours post injection, and persisted up ot 1 month transiently. Gene transfer into early embryo of this species was successfully achieved using lipofected sperm with the efficiency ranging 36.8% to 48.1%. The expression of transgene during embryonic development was shown as stage-specific and transient.

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균일혼합기 가솔린 직분사 엔진의 다중 영역 유사차원 해석을 통한 배기 및 노킹 예측 (Quasidimensional Simulation with Multi-zone Combustion Model for Homogeneous GDI Engine Emissions and Knocking)

  • 이재서;허강열;권혁모;박재인
    • 한국연소학회지
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    • 제18권1호
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    • pp.7-12
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    • 2013
  • A quasidimensional program is developed for a four stroke cycle homogeneous GDI (Gasoline Direct Injection) engine. It includes models for spray, burning rate and chemistry to predict knock and emissions. With early injection a homogeneous GDI engine goes through spark ignited, turbulent premixed combustion as in PFI (Port Fuel Injection) engines. The cylinder charge is divided into unburned and burned zone with the latter divided into multiple zones of equal mass to resolve temperature stratification. Validation is performed against measured pressure traces, NOx and CO emissions at different load and RPM conditions. Comparison is made between an empirical knock model and predictions by the chemistry model in this work.

광흡수법을 이용한 LPG 연료의 증발특성 및 연료 농도 분포에 관한 연구 (A Study on Evaporation Characteristics and Concentration Distribution of LPG fuel using Light Extinction Method)

  • 김대근;조규백;오승묵;최교남;정동수
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집D
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    • pp.708-714
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    • 2001
  • Although LP gas has lots of advantages, there has been limitation in application for automotive engine due to the several disadvantages, such as power decrease, complex fuel supply unit, and back fire etc. However LP gas direct injection engine has possibility to solve the problems above mentioned. LEM(Light Extinction Method) was employed for analysis of spacial and temporal distribution of LP gas which is directly injected into combustion chamber under various pressure and temperature conditions. The results from CVC(Constant Volume Chamber) were compared to those of RICEM(Rapid Induction, Compression and Expansion Machine) which simulate early- and late injection of direct injection engine. LPG fuel spray is affected by temperature and pressure in evaporation characteristics but it is more benefit to direct injection engine in every way such as, fuel distribution, evaporating speed and well wetting reduction.

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가솔린 엔진에서 연료분사시기와 포트특성에 따른 실린더 내 연료거동 : Part II - 저/중 와류의 경우 (In-Cylinder Fuel Behavior According to Fuel Injection Timing and Port Characteristics in an Sl Engine : Part II-With Low/Medium Swirl)

  • 엄인용;조용석
    • 한국자동차공학회논문집
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    • 제9권3호
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    • pp.9-17
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    • 2001
  • This paper is the second of 3 companion papers which investigate axial stratification process. In-cylinder fuel behavior has been investigated in the port injected Sl engine by visualizing for the purpose of understanding stratification. Planar laser light sheet from an Nd:YAG laser has been illuminated through the transparent quartz cylinder of the single cylinder optical engine and the Mie scattered light has been captured through the quartz window in the piston head with an ICCD camera. Fuel has been replaced with an air-ethanol mixture to utilize atomized fuel spray fur the visualization purposes. This results have been compared with steady flow concentration measurement. For low/medium swirl port, the early injection makes such a fuel distribution state that is upper-rich, middle-lean and lower-rich along the combustion chamber and cylinder by tumbling motion. On the other hand, the late injection induces upper-rich, middle-lean and lower-rich state due to the short fuel penetration.

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응급실에서 디클로페낙 근주 후 발생한 니콜라우 증후군 1례 (Nicolau Syndrome following Diclofenac Injection in an Emergency Department)

  • 정상원;강지훈;여준모;고재욱
    • 대한임상독성학회지
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    • 제9권2호
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    • pp.101-104
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    • 2011
  • Nicolau syndrome is a rare adverse reaction at the site of an intramuscular injection, and is characterized by severe pain immediately after the injection and rapid development of distinct skin lesions. As this syndrome is rare, it may be overlooked at the early clinical phase and subsequently, clinical outcomes may be worse due to delay in treatment. We report on a female who developed Nicolau syndrome following intramuscular diclofenac injection, which required surgical reconstruction. Understanding the characteristics of Nicolau syndrome and careful surveillance for relevant clinical features may help physicians to more quickly diagnose and treat this condition.

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인가전압이 디젤 피에조 인젝터의 분무 특성에 미치는 영향 (Effect of Induced Voltage on Spray Characteristics of Piezo Actuated Diesel Injector)

  • 이진우;배충식
    • 한국자동차공학회논문집
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    • 제18권4호
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    • pp.99-106
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    • 2010
  • A piezo-driven injector was applied with a purpose to evaluate the effect of induced voltage on spray characteristics. For this, injection rate, macroscopic imaging, ambient gas entrainment and particle sizing were carried out. It was shown that initial slope of injection rate was steeper as induced voltage increased, while slope of injection rate became mostly constant with fully opened needle. From macroscopoic imaging, longer spray tip penetration was produced with higher induced voltage. Moreover, wider spray angle was detected in the early stage of spray development, when higher induced voltage was applied. Ambient air entrainment rate was increased and particle size was reduced with higher induced voltage.

항암제투여가 가토치수에 미치는 영향에 관한 실험적 연구 (THE STUDY ON THE EFFECTS OF THE NITROGEN MUSTARD TO THE DENTAL PULPS OF RABBITS)

  • 김용화
    • 대한치과의사협회지
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    • 제15권7호
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    • pp.517-519
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    • 1977
  • The author studied the effects of cyclophosphamide to the Dental pulps of Rabbits. Eighteen rabbits were used. The experimental rabbits were given an intramuscular injection of cyclophosphamide 50mg. per 1.5Kg. of body weight. In order to investigate effects of cyclophosphamide to the pulps of rabbits the control and experimental rabbits were sacrificed, on 1,3,5,7,10, and 14 days after injection of cyclophosphamide and made preparations for histopathologic findings. The results were as fallows. 1. In the early stage after injection of cyclophosphamide, retrcgrade degeneration of pulps such as infiltration of inflammatory cells, vacuolization, hyaline degeneration and reticular tissue atrophy in pulps were revealed. 2. The pulps were recovered from 10 to 14 days after injection of cyclophosphamide.

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수소-예혼합 압축착화 엔진에서 착화제인 DME/diesel이 엔진 연소에 미치는 영향 (Effects of DME/Diesel as an ignition promoter on combustion of hydrogen homogeneous charge compression ignition)

  • 전지연;박현욱;배충식
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2013년도 제46회 KOSCO SYMPOSIUM 초록집
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    • pp.37-40
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    • 2013
  • Hydrogen-dimethy ether (DME) and hydrogen-diesel compression ignition engine combustion were investigated and compared each other in a single cylinder compression ignition engine. Hydrogen and DME were used as low carbon alternative fuels to reduce green house gases and pollutant. Hydrogen was injected at the intake manifold with an injection pressure of 0.5 MPa at fixed injection timing, $-210^{\circ}CA$ aTDC. DME and diesel were injected directly into the cylinder through the common-rail injection system at injection pressure of 30 MPa. DME and diesel inejction timing was varied to find the optimum CI combustion to reduce CO, HC and NOx emissions. When DME was injected early, CO and HC emissions were high while NOx emission was low. Fuel consumption, heat release rate, and exhaust emissions were measured to analyze each combustion characteristics of each ignition promoter. Fuel consumption was decreased when diesel was used as an ignition promoter. This is due to the lower volatility of diesel which created more stratified charge than DME.

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DME 분사 시기 조절을 통한 수소-DME 부분 예혼합 압축착화 연소 제어 (Combustion Control through the DME Injection Timing in the Hydrogen-DME Partially Premixed Compression Ignition Engine)

  • 전지연;배충식
    • 한국연소학회지
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    • 제18권1호
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    • pp.27-33
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    • 2013
  • Hydrogen-dimethy ether(DME) partially premixed compression ignition(PCCI) engine combustion was investigated in a single cylinder compression ignition engine. Hydrogen and DME were used as low carbon alternative fuels to reduce green house gases and pollutant. Hydrogen was injected at the intake manifold with an injection pressure of 0.5 MPa at fixed injection timing, $-210^{\circ}CA$ aTDC. DME was injected directly into the cylinder through the common-rail injection system at injection pressure of 30 MPa. DME inejction timing was varied to find the optimum PCCI combustion to reduce CO, HC and NOx emissions. When DME was injected early, CO and HC emissions were high while NOx emission was low. As the DME injection was retarded, the CO and HC emissions were decreased due to high combustion efficiency. NOx emissions were increased due to the high in-cylinder temperature. When DME were injected at $-30^{\circ}CA$ aTDC, reduction of HC, CO and NOx emissions was possible with high value of IMEP.