• 제목/요약/키워드: nitrogen species

검색결과 1,085건 처리시간 0.03초

BETA-AMYLOID INDUCES OXIDATIVE AND/OR NITRATIVE PC12 CELL DEATH: POSSIBLE INVOLVEMENT OF INFLAMMATORY CASCADES

  • Jang, Jung-Hee;Surh, Young-Joon
    • 한국독성학회:학술대회논문집
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    • 한국독성학회 2002년도 Current Trends in Toxicological Sciences
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    • pp.94-94
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    • 2002
  • Oxidative stress induced by reactive oxygen and/or nitrogen species has been considered as a major cause of cellular injuries in a variety of neurodegenerative disorders including Alzheimer's disease (AD). Inflammatory as well as oxidative tissue damage has been implicated in pathophysiology of AD, and non-steroidal anti-inflammatory drugs have been reported to have beneficial effects in the treatment or prevention of AD.(omitted)

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Protective Effects of Naturally Occurring Antioxidants against beta-Amyloid-Induced Oxidative and Nitrosative Cell Death

  • Jang, Jung-Hee;Surh, Young-Joon
    • 한국독성학회:학술대회논문집
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    • 한국독성학회 2003년도 춘계학술대회 논문집
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    • pp.93-94
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    • 2003
  • beta-Amyloid peptide is considered to be responsible for the formation of senile plagues that accumulate in the brains of patients with Alzheimers disease. There has been a paucity of evidence to support the involvement of reactive oxygen and/or nitrogen species (ROS and/or RNS) in beta-amyloid-induced neuronal cell death. (omitted)

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고밀도 플라즈마 내에서의 plasma species의 변화 (The generation of nitrogen ion species in high-density plasma with HCD)

  • 김상권;김성완
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2009년도 춘계학술대회 논문집
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    • pp.234-234
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    • 2009
  • 고밀도 플라즈마 질화를 위해 장비 내에 보조 HCD (Hollow Cathode Discharge) 전극을 설치하여 고밀도의 플라즈마가 발휘되도록 장비를 구축하였다. 기존 bias 플라즈마 질화는 1-10Torr의 공정압력인데 반하여 $10^{-1}-10^{-2}$Torr의 비교적 고 진동에서 고밀도의 플라즈마를 발생시켰다. HCD 질화는 bias plasma 질화 공정의 플라즈마를 비교하면 가스 비의 영향이 매우 큰 것드로 관찰되었으며 기존에 발표된 플라즈마 질화 관련 모델과 비교하여 관찰된 플라즈마 내에서는 ion species가 실제 공정에서도 영향을 미치는 것을 알 수 있었다.

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BETA-AMYLOID INDUCES OXIDATIVE AND/OR NITRATIVE PC12 CELL DEATH VIA PRO-INFLAMMATORY MECHANISMS

  • Jang, Jung-Hee;Surh, Young-Joan
    • 한국독성학회:학술대회논문집
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    • 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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    • pp.115-115
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    • 2001
  • Oxidative stress induced by reactive oxygen and/or nitrogen species has been considered as a major cause of cellular injuries in a variety of neurodegenerative disorders including Alzheimers disease (AD). Inflammatory as well as oxidative tissue damage has been associated with pathophysiology of AD, and non-steroidal anti-inflammatory drugs have been reported to have beneficial effects in the treatment or prevention of AD.(omitted)

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레이저 자기공명 분광기용 광대역 CO 레이저의 개발 (Development of a Broad-Band CO laser for the Laser Magnetic Resonance Spectrometer)

  • 김용평
    • 한국광학회:학술대회논문집
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    • 한국광학회 1989년도 제4회 파동 및 레이저 학술발표회 4th Conference on Waves and lasers 논문집 - 한국광학회
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    • pp.70-72
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    • 1989
  • The laser magnetic resonance (LMR) which makes use of paramagnetic properties of transient species is a powerful technique for the study of molecular radical ions. A liquid nitrogen cooled cw CO laser is developed for the LMR spectrometer in the mid-infrared region of the spectrum. The laser mid-infrared region of the spectrum. The laser system is designed to allow broad-band operation from 5 to 8${\mu}{\textrm}{m}$. The design details will be presented.

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Phenolic Compounds from Barks of Pinus densiflora siebold et Zuccarini and Their NO Production Inhibitory Activities.

  • Kwon, Young-Min;Yeom, Seung-Hwan;Kim, Min-Ki;Lee, Jae-Hee;Lee, Min-Won
    • 대한약학회:학술대회논문집
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    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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    • pp.374.1-374.1
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    • 2002
  • The barks o.f Pinus densiflara representative Pinus species graws in Korea, have been used for oriental traditional medicine as the remedies for rheumatitis. hemorrhage and cancer. Water soluble fraction of 80% acetone extracts from the barks af Pinus densiflera (PDB) showed nitrogen monoxide(NO) production inhibitory activity in IFN-${\gamma}$. LPS stimulated RAW 264.7 cell. (omitted)

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Grazing Effects on Floristic Composition and Above Ground Plant Biomass of the Grasslands in the Northeastern Mongolian Steppes

  • Hayashi, Ichiroku;Kawada, Kiyokazu;Kurosu, Mayu;Batjargal, Amgaa;Tsundeekhuu, Tsagaanbandi;Nakamura, Toru
    • Journal of Ecology and Environment
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    • 제31권2호
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    • pp.115-123
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    • 2008
  • We describe plant biomass in the grasslands of the Mongolian steppe obtained using a quadrat sampling technique. Four sites were studied in the northeastern Mongolia located between $47^{\circ}12'N$ and $47^{\circ}40'N$ and $102^{\circ}22'E$ and $112^{\circ}24'E$, which were typical grasslands of the steppe. Biomass, carbon and nitrogen content were determined for the plants collected from the grazed and ungarazed stands. With the measurements above, we expect to obtain information on grazing effects on the grasslands and carbon sequestration of the grassland from the air. In order to estimate the biomass without destroying the stands, we derived an equation to describe the relationship between plant biomass and v-value using plant height and species coverage within the stand. Estimated plant biomass in the ungrazed and grazed stands ranged between $108.0\;g\;m^{-2}$ and $13.4\;g\;m^{-2}$ and between $97.5\;g\;m^{-2}$ and $14.1\;g\;m^{-2}$ in late June 2005, respectively. Litter in the ungrazed and grazed stands ranged from $330.3\;g\;m^{-2}$ to $78.4\;g\;m^{-2}$ and from $188.0\;g\;m^{-2}$ to $20.3\;g\;m^{-2}$, similarly. Average carbon and nitrogen contents in plants and in litter were 43.0% and 1.9% and 33.7% and 1.4%, respectively. In study sites at Baganuur, the carbon and nitrogen content of plant materials (plant plus litter) was $118.4\;g\;m^{-2}$ and $4.7\;g\;m^{-2}$ on 30 June 2005.

한계령풀(Leontice microrhyncha) 개체군의 식생과 토양특성 (A Study on Vegetation Structure and Soil condition of Leontice microrhyncha Population)

  • 권재환;권혜진;송호경
    • 한국환경복원기술학회지
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    • 제13권3호
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    • pp.84-93
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    • 2010
  • This study was carried out to analyze the vegetation properties, soil characteristics and ordination of Leontice microrhyncha population in South Korea. The Leontice microrhyncha population was classified into Quercus mongolica dominant population, Morus bombycis dominant population, Fraxinus mandshurica population and Leontice microrhyncha typical dominant. The Leontice microrhyncha population was located at an elevation of 633m to 1,336m in Korea. In the study sites, soil organic matter, total nitrogen, available phosphate, exchangeable potassium, exchangeable calcium, exchangeable magnesium, cation exchange capacity and soil pH were 8.40~10.58%, 0.42~0.61%, 14.15~25.07mg/kg, 0.44~0.59cmol$^+$/kg, 2.35~6.33cmol$^+$/kg, 0.35~0.98cmol$^+$/kg, 26.04~33.48cmol$^+$/kg and 4.69~5.32 respectively. Morus bombycis dominant population was found in the low elevation and gentle sloped area that has high percentage of phosphoric acid and less percentage of total nitrogen, exchangeable calcium, exchangeable magnesium than other dominant population. Fraxinus mandshurica dominant population and Leontice microrhyncha typical population were found in the comparatively high elevation area that has low percentage of phosphoric acid and high percentage of total nitrogen, exchangeable calcium, exchangeable magnesium. Quercus mongolica dominant population was found in the medium elevation area that has medium percentage of total nitrogen, exchangeable calcium, exchangeable magnesium.

보리수나무의 질소고정활성에 대한 환경요인의 영향 (Effects of Environmental Factors on the Nitrogen Fixation Activity in Elaeagnus umbellata)

  • Song, Seung-Dal;Lee, Kyung-Jin;Park, Tae-Gyu;An, Chung-Sun;Kim, Joon-Ho
    • The Korean Journal of Ecology
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    • 제16권2호
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    • pp.159-168
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    • 1993
  • The seasonal changes of symbiotic nitrogen-fixation activity and environmental factors of autumn olive plant (Elaeagnus umbellata Thunb.), which is an important constituent species of temperate vegetation and a non-leguminous root nodule plant interacting with Frankia sp., were quantitatively analyzed inthe natural vegetations during hegrowing period. The acetylene redution April and showed two peaks of 133 and $145{\mu}M\;C_2H_4\;{\cdot}\;gfw^{-1}\;{\cdot}\;hr^{-1}$ in early June and mid September. The nitrogenase activity decreased to 10~30% during hot dry summer frommid June to the end of August, and disappeared during the dormant period of winter. The optimum rhizoshere. diurnal change showed the maximum activity in the mid-day and the minimum in the mid-night. The average contents of total nitrogen in each organ changed in the ranges of 42.5~40.1, 40.2~36.3, 30.3~28.6 and 18.4~16.2mgN $gdw^{-1}$ for nodule, leaf, root, and stem, respectively. The soil conditions of rhizosphere were weak acidic, ad seasonal variations of $NO_3^--N,\;NH_4^+-N,\;PO_4^{3-}-P$ and water contents were in the ranges of 48.3~79.5ppm,5.1~13.9ppm, 4.4~$9.9{\mu}M$ and 14.5~39.4%, respectively.

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Optimal Growth Conditions for the Two Euryhaline Cyanobacterial Clones, Anabaena sp. CB-MAL21 and CB-MAL22 Isolated from Mankyeong Estuary, Korea

  • Kim, Young-Geel;Myung, Geum-Og;Yih, Won-Ho;Shin, Yoon-Keun
    • ALGAE
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    • 제19권2호
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    • pp.145-148
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    • 2004
  • As a result of the 2-year monthly monitoring of the phytoplankton community at 3 stations in Mankyeong Estuary, Korea, we learned that cyan bacterial species of the genus Anabaena occurred at most sampling points with huge salinity differences (0.1-32.5 psu). We isolated several clones of Anabaena spp. from the monitoring stations, and screen out two euryhaline and nitrogen-fixing Anabaena clones, CB-MAL21 and CB-MAL22. The two clones were grown under various environmental gradients such as temperature (20, 30, 35 and 40$^{\circ}C$), salinity (0, 2, 5, 15 and 30psu), and $PO_4^{3-}$-P concentration (0, 1.6, 8.0, 40 and 200 ${\mu}M$M). Growth of CB-MAL21 and CB-MAL22 was measured by daily monitoring of chlorophyll fluorescence from each experimental culture for more than three serial transfers. Both the two experimental clones did not grow at 0psu. Maximal growth rates of the two clones were markedly reduced at lower $PO_4^{3-}$-P concentrations showing negligible growth at 0 and 1.6 ${\mu}M$M. However, growth of CB-MAL21 was not affected by low $NO_3^--$ concentration in culture media, showing the nitrogen-fixing ability. Maximum biomass yields of the two clones decreased dramatically at 35 and 40$^{\circ}C$. Optimal growth conditions for the two experimental clones were determined to be 20-30$^{\circ}C$, 40 ${\mu}M$M $PO_4^{3-}$-P, and wide salinity range from 5.0 to over 30psu. Best growth of CB-MAL21 was shown at (20$^{\circ}C$-15psu), which is less saline and cooler condition than those (i.e., 30$^{\circ}C$-30psu) for the best growth of CB-MAL22. The euryhaline and nitrogen-fixing CB-MAL21 strain thus can be a candidate laboratory culture for the future cyan bacterial marine biotechnology in temperate coastal waters.