• 제목/요약/키워드: oil-degradation

검색결과 405건 처리시간 0.027초

오미자 종자 정유에 의한 인체백혈병 U937 세포의 apoptosis 유도 (Apoptotic Cell Death of Human Leukemia U937 Cells by Essential Oil purified from Schisandrae Semen)

  • 최영현
    • 생명과학회지
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    • 제25권2호
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    • pp.249-255
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    • 2015
  • 오미자 종자에서 추출된 정유(Schisandrae Semen essential oil, SSeo)의 항암활성 및 작용 기전 해석을 위하여 U937 백혈병 세포를 대상으로 apoptosis 유도 여부를 조사하였다. SSeo 처리에 의한 U937 세포의 증식 억제는 apoptosis 유도와 연관성이 있음을 DAPI 염색을 통한 apoptotic body 출현의 증가, agarose gel 전기영도에 의한 DNA의 단편화 유도 및 flow cytometry 분석에 의한 Sub-G1기 세포 빈도의 증가로 확인하였다. SSeo 처리에 의한 apoptosis 유도에서 IAP family 단백질에 속하는 XIAP, cIAP-1 및 survivin의 발현 감소와 anti-apoptotic Bcl-2 단백질의 발현 저하, DR4 및 DR5의 발현 증가와 연관성이 있었다. SSeo 처리는 또한 Bid truncation, 미토콘드리아 기능 손상, caspases (-3, -8 and -9)의 활성화와 활성형 caspase-3의 기질 단백질인 PARP의 단편화를 동반하였다. 본 연구의 결과는 오미자 정유의 생화학적 항암기전 해석을 이해하고 향후 지속적인 연구를 위한 기초자료로서 활용될 수 있을 것으로 생각된다.

Intravascular Tumour Targeting of Aclarubicin-loaded Gelatin Microspheres Preparation biocompatibility and biodegradability

  • Lee, Kang-Choon;Koh, Ik-Bae
    • Archives of Pharmacal Research
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    • 제10권1호
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    • pp.42-49
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    • 1987
  • This study is to evaluate the potential use of aclarubicin-loaded gelatin microspheres as an intravascular biodegradable drug delivery system for the regional cancer therapy. The diameter of the microspheres prepared by water in oil emulsion polymerization could be controlled by adjusting the stirring rate in the range of 10-50 $\mu$m : D(in $\mu$m) = -73.8 log (rpm) + 262.7. The addition of proteolytic enzyme increased the in vitro aclarubicin release but it did not change the amount of the initial burst release which reached about 45%. Microspheres injected intravenously into the mouse tail vein embolized only to the lung when observed by fluorescence microscopy. From histological examination following injection of gelatin microspheres into mouse femoral muscle, mild inflammation was observed from the appearance of neutrophils after 2 days and rapid repair process was confirmed thereafter. Biodegradation process of gelatin microspheres lodged on the pulmonary capillary bed was followed up by microscopic observation; degradation was taking place by about 36 hrs, followed by severe damage on the spheerical shape and microspheres was no longer found 10 days after injection.

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송전용 OF 케이블의 절연특성 분석방법에 대한 고찰 (The Investigation of Analytical Techniques for Insulation Characteristics of Oil-Filled Transmission Cables)

  • 김종은;서광석;김정태;이전선;구자윤
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 D
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    • pp.1608-1610
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    • 1999
  • To find effective diagnostic method for Transmission OF cables, various characterizations were carried such as DGA (dissolved gas analysis), water contents, total acidity and AC breakdown voltage. It was found that the result was varied by sampling and container. The results from those characterization method showed the present condition and history very well and could be used to estimate the degree of degradation of cables.

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Ruminal and Intestinal Digestibility of Some Tropical Legume Forages

  • Khamseekhiew, B.;Liang, J.B.;Wong, C.C.;Jalan, Z.A.
    • Asian-Australasian Journal of Animal Sciences
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    • 제14권3호
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    • pp.321-325
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    • 2001
  • Two experiments were conducted to examine the degradation rates of 4 tropical legume forages in rumen and intestine of Kedah-Kelantan (KK) cattle. Three KK cattle, averaging $173{\pm}17.15kg$ each fitted with a permanent ruminal and a T-shaped duodenal cannulae were used. The cattle were fed a maintenance diet (1% DM of their body weight) composing of 60% oil palm frond (OPF) pellet and 40% of a legume mixture of Arachis pintoi (AP) and Leucaena throughout the study. The overall DM and CP degradabilities in the rumen for Gliricidia sepium (GS) and AP were significantly higher than those for Leucaena leucocephala-Bahru (LB) and Leucaena leucocephala-Rendang (LR). This implies that LB and LR would have higher dietary protein flows into the intestine for the more efficient enzymatic digestion. However, the results of the present study suggested only limited proportions of the ruminal undegraded protein in the Leucaenas were digested in the intestine.

열 열화에 의한 주상변압기의 수명 손실 (Life Loss of Pole Mounted Transformers by Thermal Aging)

  • 정종만;이병성;송일근
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2005년도 춘계학술대회논문집
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    • pp.209-213
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    • 2005
  • To enhance the reliability of distribution transformers in service and to reduce the cost of maintaining and replaceing these, the condition and life of those insulating system should be evaluated accurately and the time to replace should be determined economically. Since the transformer failures related to insulation failure indicates that the primary cause is normally mechanical failure of integrity due to loss of mechanical strength as a result of degradation, the tensile strength characteristics of paper during ageing under accelerated conditions in insulating oil and research trends for assessing the life of insulating paper were investigated.

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변압기 열화진단을 위한 절연유중 퓨란화합물 최적 분석기법 고찰 (Proposals for an Optimum Analysis Method for Furanic Compound in Insulating Oil for Paper Degradation Assessment)

  • 박현주;김석분
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.2047_2048
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    • 2009
  • 절연유중 용존가스분석에 의한 진단방법은 변압기 내부에 이상유무를 판단하는 좋은 방법이다. 이중에서 $CO_2$와 CO가스에 의한 열화진단도 가능하나, 이들 가스들은 운전 중인 변압기 내에서 절연지 속으로 매우 잘 흡수되어 진다고 알려져 있다. 절연지는 도체의 주위를 감싸고 있어서 변압기를 폐기할 때까지는 종이로 된 절연물의 상태를 분석하기가 어렵기 때문에 절연유중에 용해되어 있는 CO와 $CO_2$ 농도를 분석하여 절연지의 열화 정도를 판단하고 있지만, 절연유의 일반적인 열화에 의해서도 이들 가스가 발생하기 때문에 정확하게 판단하기가 어렵다. 따라서, 절연물의 열화정도를 파악하기 위해 절연유중의 퓨란화합물에 대한 최적 분석법을 도출하여 열화진단에 대한 정확도를 높이고자 하였다.

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유입변압기의 절연열화물 분석에 의한 열화진단 (Diagnostics of Oil Immersed Transformer by Analysis of Degradation Products)

  • 박현주;남창현;윤여찬
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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    • pp.572-574
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    • 2005
  • 전력용 변압기 내부의 주요 부품들은 권선과 코일 및 절연물로 크게 나눌 수 있는데, 이들 구성물질 중 권선과 코일은 $30\sim40$년 운전기간동안 별다른 문제를 야기하지 않아 일반적으로 변압기의 수명은 거의 절연물의 수명과 일치한다고 알려져 있다. 특히 절연지의 열화에 매우 의존적이다. 절연지의 인장강도나 중합도 분석 등은 상당량의 절연지를 필요로 하기 때문에 운전 중 변압기의 열화진단을 위해서는 부적절하다. 따라서 HPLC 에 의한 furfural 분석은 변압기의 절연지의 둔해 정도를 평가하는 좋은 방법이 되고 있다. 이 논문은 그동안 한전의 변압기들에 대한 furfural 분석결과와 경년열화실험을 통한 절연열화물들에 대한 분석결과를 토대로 변압기의 수명평가를 위한 기초를 마련하고자 하였다.

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계장화 압입시험법을 이용한 보일러 설비의 고온 기계적 물성 측정과 수명 평가 (High-temperature Mechanical Properties Measurement and Life Assessment of Boiler Equipment by Instrumented Indentation Technique)

  • 노동성;홍정화;김광호;이정준
    • 한국안전학회지
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    • 제24권3호
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    • pp.1-6
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    • 2009
  • Recently power plants and oil refineries are focusing on capacity enlargement for better efficiency through higher temperature and higher pressure. Thickness of boiler tubes becomes lessened due to oxidation and erasion caused by high temperature bums gas flowing over tubes outside. Accordingly, mechanical stress of tubes is increasing and that is a critical factor to make a crack and fracture. To prevent those sorts of accidents, aging assessment for proper periodic repair and replacement should be conducted reliably and reasonably. We performed IIT test on Cr-Mo steel, one of the most heat-resistant materials for facilities in power plants, and we report the test result and the considerable effectiveness of IIT test.

Effects of the Hovenia dulcis THUMBER var. Koreana Nakai Extracts on Hepatoprotective Activities and Improvement of Hepatofunction

  • Hwang Hyun-Ik;Lee In-Soon;Chae Hee-Jun;Moon Hae-Yeon
    • 대한의생명과학회지
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    • 제11권2호
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    • pp.237-242
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    • 2005
  • The Hovenia extracts showed a significant hepato-protective activity against alcohol and CC4-induced hepatotoxicity. Injection of CC4 and alcohol induced liver injury and increased serum GOT (glutamic oxaloacetic transaminase) and GPT (glutamic pyuvic transaminase) levels in injured rats. The ADH (alcohol dehydrogenase)-like and ALDH (aldehyde dehydrogenase)-like activities in the Hovenia extracts were studied. Their activities in the extracts of Hovenia wood were higher than the extracts of other parts of Hovenia. And then Hovenia wood extracts have high effects on the alcohol and acetealdehyde degradation. The Hovenia extracts were decreased concentration of fusel oil. The ADH-like and ALDH-like activities in the Hovenia wood extract were 1.14 $unit/{\mu}l$, 0.33$unit/{\mu}l$ respectively.

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Role of Unstable Phenanthrene-Degrading Pseudomonas species in Natural Attenuation of Phenanthrene-Contaminated Site

  • Prakash, Om;Lal, Rup
    • 한국미생물·생명공학회지
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    • 제41권1호
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    • pp.79-87
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    • 2013
  • An unstable yet efficient phenanthrene-degrading bacterium strain Ph-3 was isolated from a petroleum-contaminated site at the Mathura Oil Refinery, India. The strain was identified as Pseudomonas sp. using a polyphasic approach. An analysis of the intermediates and assays of the degradative enzymes from a crude extract of phenanthrene-grown cells showed a novel and previously unreported pattern of 1, 2-dihydroxy naphthalene and salicylic acid production. While strain Ph-3 lost its phenanthrene- degrading potential during successive transfers on a rich medium, it maintained this trait in oligotrophic soil conditions under the stress of the pollutant and degraded phenanthrene efficiently in soil microcosms. Although the maintenance and in vitro study of unstable phenotypes are difficult and such strains are often missed during isolation, purification, and screening, these bacteria constitute a substantial fraction of the microbial community at contaminated sites and play an important role in pollutant degradation during biostimulation or monitored natural attenuation.