• Title/Summary/Keyword: 억제요인

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신합성 화합물 1,4-Naphthoquinone 유도체들의 세포독성 기전에 관한연구

  • 정명희;오지영;정세영
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1992.05a
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    • pp.41-41
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    • 1992
  • 새로이 합성된 1,4-Naphthoquinone(1,4-NQ) 화합물의 세포독성의 확인과 그 작용기전을 규명코져 본 실험을 수행하였다. 분리된 흰쥐 간세포를 1,4-NQ유도체들과 반응 시켰을때 이들 중 YC 001과 YC 008은 독성을 나타냈으나 YC 012는 독성율 나타내지 아니하였다. 세포독성은 세포치사, lactate dehydrogenase 유출 및 산소소비의 억제등으로 확인하였다. 세포 독성의 기전은 mitochondria에서의 전자흐름 차단작용과 microsome에서 redox-cycling 기전에 의한 산소리디칼 생성의 두가지에 대하여 검토하였다. 분리된 mitochondria를 YC 001과 YC 008은 반응 시켰을때 mitochondria의 호흡은 완전히 억제되었다. 그러나 YC 012는 전혀 작용을 나타내지 아니하였다. 이는 간세포에 대한 독성작용과 일치하는 결과이며 따라서 mitochondria에 대한 억제 작용은 이들의 세포독성에 주요한 요인이라고 추측되었다.

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Properties of Soil Suppressiveness to Cucumber Wilt, caused by Fusarium oxysporum f. sp. cucumerinum Owen (오이 덩굴쪼김병의 발병(發病)을 억제(抑制)하는 토양(土壤)의 특성(特性)에 관(關)하여)

  • Park, Chang-Seuk;Cho, Yong-Sup
    • Korean journal of applied entomology
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    • v.24 no.2 s.63
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    • pp.85-95
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    • 1985
  • It has been tried to find effective biological control measures involved in nature of soil suppressiveness to fusarium wilt of cncumber caused by Fusarium oxysporum f. sp. cucumerinum Owen. Total 28 soil samples were obtained from Jinju, Haman, Namji, Milyang and Suncheon vinyl house area. The disease response of test soil was quantified in terms of DI50 value which caculated from log-probit transformation of diseases response curves. Soils designated 5 from Jinju, 7 from Suncheon, 22 from Namji were recognized as suppressive to fusarium wilt of cucumber. This suppressiveness was completely nullified after autoclave. The disease suppressiveness of tested soil did not indicate any consistency according to either chemical property or texture of soil. Conidial germination, induction and germination of chlamydospore were markedly inhibited in supprerssive soil compared to those in intermediate or conducive soils, however, mycelial lysis did not appear to have direct relationship with disease suppressiveness of given soil. Population density of fluorescent Pseudomonads and Bacillus spp. in the soil originated from different degree of suppressiveness were not different significantly but the number of lytic bacterial plaques measured by triple layer agar method was remarkably higher in suppressive soil than that in intermediate or conducive soil.

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Studies on Ciliary Activity of Bivalve, Tapes philippinarum , During Developmental Stages (성장단계에 따른 이매구, Tapes philippinarum 의 직모 연동능에 관한 연구)

  • 최기철;이춘구
    • The Korean Journal of Zoology
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    • v.4 no.2
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    • pp.1-6
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    • 1961
  • 바지락(Tapes philippinarum) 직모연동능에 미치는 몇가지 중요한 환경 요인의 영향에 관하여 생리학적 방법으로 조사하였다. 1. 산화환워전위 측정결과, 치매일수록 성매에 비하여 무기상태에 대한 저항성이 낮았다. 2. 치매의 직모연동능은 17$\pm$1$^{\circ}C$에서 산소장력 저하상태로 \ulcorner긴 20분후, 성매의 약 1/2 이하로 감소되었따. 3. 한편 수온 13$\pm$1$^{\circ}C$dpt는 직모운동능이 같은 산소장력의 저하에 의하여서도 성매 치매 모두가 비슷한 경향으로 급격히 억제되었다. 4. 수온 1$0^{\circ}C$에서 20 $^{\circ}C$로 옮겼을 때 성매와 치매의 직모연동능은 수온으로 인하여 거의 평행하게 최고치 약 2305까지 촉진되었다. 5. 특히 치매에 있어서는 부유토분자의 낮은 혼촉도에 의하여 직모연동능이 감소되었다. 6 바지락은 광감성물질임을 밝혔다. 7 . 이들 결과로서 치매의 높은 치사율은 해저서식지의 불리한 환경요인 특히 중량요인에 좌우되는 것임이 확실하다. 치사율을 좌우하는 가장 중요한 요인은 용존산소의 결지, 저온 그리고 심한 부유토의 온촉도이며 반하여 약간의 염도변동은 그리 치명적인 것이 아니다.

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Vascular Endothelial Growth Factor Inhibits irradiation-induced Apoptosis in Human Umbilical Vein Endothelial Cells (혈관내피세포에서 Vascular Endothelial Growth Factor가 방사선에 의해 유도된 apoptosis에 미치는 영향)

  • Lee Song Jae;Kim Dong-Yun
    • The Journal of Korean Society for Radiation Therapy
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    • v.14 no.1
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    • pp.165-174
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    • 2002
  • Vascular endothelial growth factor (VEGF) has been identified as a peptide growth factor specific for vascular endothelial cells. In this study, we examined the effect of VEGF on radiation induced apoptosis and receptor/second messenger signal transduction pathway for VEGF effect in human umbilical vein endothelial cells (HUVECs). VEGF was found to protect HUVECs against the lethal effects of ionizing radiation by inhibiting the apoptosis induced in these cells by radiation exposure. VEGF (1-30 ng/ml) dose dependently inhibited apoptosis by irradiation. Pre-treatment with Flt-1 and Flk-l/KDR receptor blocked the VEGF-in duced antiapoptotic effect. Phosphatidylinositol 3'-kinase (PI3-kinase) specific inhibitor, Wortman in and LY294002, blocked the VEGF-induced antiapoptotic effect. These data suggest that VEGF may play an important role in survival of HUVECs due to the prevention of apoptotic cell death caused by some stresses such as ionizing radiation.

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Factors and Recovery of Herbicide Phytotoxicity on Direct-seeded Rice - 2. Phytotoxicity of Herbicide with Nutrient Condition (직파(直播) 벼의 제초제(除草劑) 약해(藥害) 요인(要因)과 회복(回復) 연구(硏究) - 2. 영양(營養) 조건(條件)에 따른 약해(藥害))

  • Im, Il-Bin;Usui, K.
    • Korean Journal of Weed Science
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    • v.17 no.1
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    • pp.24-30
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    • 1997
  • The influence of nutrients on the phytotoxicity of herbicides (bensulfuron-methyl, pyrazosulfuron-ethyl, imazosulfuron, dimepiperate, and molinate) was investigated in controlled-environment growth chamber with direct-seeded rice (Oryza sativa L. cv. Dongjin). The phytotoxicity of bensulfuron-methyl, pyrazosulfuron-ethyl, and imazosulfuron for rice was greater in nutrient culture than in no-nutrient condition. The root growth of rice applied with these herbicides was more inhibited than the shoot growth. The most severe inhibition was obtained with pyrazosulfuron-ethyl application. The growth inhibition of rice applied by dimepiperate was increased under no-nutrient culture condition. Dimepiperate suppressed more remarkably shoot growth than root. Especially the shoot elongation was much more inhibited than the others. The shoot growth inhibition in rice applied by molinate was severer than the root. The shoot growth was reduced under nutrient culture condition, while the root growth was reduced under no-nutrient culture.

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A Study of the relation between class and the welfare attitudes and regulating effects of education (계급·계층이 복지정책에 대한 태도에 미치는 영향과 교육변인의 조절효과 연구)

  • Kim, HeeJa
    • 한국사회정책
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    • v.20 no.2
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    • pp.35-68
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    • 2013
  • Class has been the factor that affects welfare attitudes in western societies. But the results of the studies on affects of class in Korea are not consistent. This Study focuses on the relations between three class variables-income, status in employment, occupation-and the Korean attitudes on welfare policy and examines the regulating effects of education on that. Attitudes on welfare policy consist of 'reinforcement of established welfare programs', 'expansion into new welfare area' and 'universalism in welfare policy.' The result shows that all three class variables, education and age do not affect the attitudes to 'reinforcement of established welfare programs.' Age and class variables affects the attitudes to 'expansion into new welfare area' statistically, but education does not. Education explains largest parts of the attitudes to 'universalism in welfare policy.'

Inhibitory Effect of Taraxacum mongolicums (蒲公英) on NO Production in LPS-stimulated Macrophages (LPS로 자극된 대식세포에서 포공영의 NO 생성 억제 효과)

  • Ha, Hyeon-Hee;Park, Sun-Young;Ko, Woo-Shin;Jang, Jeong-Su;Kim, Young-Hee
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.20 no.3
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    • pp.98-106
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    • 2007
  • 포공영(蒲公英)은 예로부터 청열해독약(淸熱解毒藥)으로 사용되어 왔으며 NO가 염증의 한 요인이기 때문에 포공영의 항염증 작용기작을 밝히기 위하여 LPS로 자극된 대식세포주 RAW264.7 세포에서 포공영 열수 추출물 (AETM)의 NO 생성에 미치는 효과를 조사하였다. 포공영은 NO 생성 및 iNOS 단백질 발현, iNOS mRNA 발현을 저해하였으며, 전사인자인 $NF-kB$의 핵으로의 이동을 억제하였다. 또한 LPS에 의해서 활성화되는 ERK/MAPK 효소의 활성을 현저히 억제하였다. 이 결과들로 보아 포공영의 항염증 작용이 ERK/MAPK 활성 저해 및 $NF-kB$ 활성 저해로 인한 iNOS 발현의 억제 때문인 것으로 사료된다.

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A Test of Situational Action Theory for Explaining the Moderating Effect of Self-Control and Deterrence in Digital Piracy: Comparing Download with Upload Behavior (디지털 저작권침해 행위에서 상황행위이론의 적용을 통한 자기통제와 처벌억제의 조절효과: 다운로드와 업로드 행위의 비교)

  • Lee, Seong-Sik;Jang, Ha-Young;Lim, Su-Kyung
    • Journal of Digital Convergence
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    • v.19 no.4
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    • pp.9-17
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    • 2021
  • This study test a situational action theory for explaining online download and upload digital piracy and examines the moderating effect of self-control and punishment. Then it tests the moderating effect of self-control in high morality and low moral rule environments and tests the moderating effect of perceived punishment in low morality and high moral rule environments. Using data from 317 college students in Seoul, In case of download, results show that self-control does not control the effects of high morality and low moral rule on it. In addition, it is found that perceived punishment does not control the effects of low morality and high moral rule on it. In case of upload, results show that self-control does not control but increase the effects of high morality and low moral rule on it, while perceived punishment controls the effects of high morality and low moral rule on it.

액체 로켓 추진기관의 연소불안정 현상

  • 윤명원;윤재건
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 1997.04a
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    • pp.13-23
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    • 1997
  • 액체 로켓 추진기관의 개발에 가장 큰 장애요인은 연소불안정 현상이다. 연소불안정이 생기는 원인과 연소실내 음향효과에 따른 분류를 행하고 액체 로켓 추진기관 개발에서 발생하였던 연소 불안정 현상을 추진제 종류와 특성에 따라 살펴보았다. 또한 추진기관의 연소 안정성을 보장하기 위한 성능확인 시험과 연소 불안정을 억제하는 능동적, 수동적 방법에 관하여 기술하였다.

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"공동주택 리모델링 기준 완화"

  • 대한설비건설협회
    • 월간 기계설비
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    • s.139
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    • pp.17-19
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    • 2002
  • 금년 3월부터 사용검사 후 10년 이상 경과된 아파트 등 공동주택은 단지 또는 동별 입주자 전원의 동의를 얻으면 리모델링이 허용될 전망이다. 규제개혁위원회는 최근 건설교통부가 제출한 공동주택관리령 개정안 및 공동주택관리규칙 개정안을 심의, 무분별한 공동주택의 재건축 사업으로 인한 사회적 자원 낭비 요인을 억제하고 리모델링을 활설화하기 위해 이같이 권고키로 의결하였다.

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