• Title/Summary/Keyword: 시간의존효과

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Glutamate-Induced Serotonin Depletion in Fetal Rat Brainstem Cultures (흰쥐태 뇌간의 배양에서 Glutamate에 의한 Serotonin의 고갈)

  • Park, Sang-Wook;Wie, Myung-Bok;Song, Dong-Keun;Kim, Yong-Sik;Kim, Yung-Hi
    • The Korean Journal of Pharmacology
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    • v.29 no.2
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    • pp.189-193
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    • 1993
  • Exposure of dissociated cultures from fetal rat brainstem to glutamate for upto 6 h decreased cellular contents of 5-hydroxytryptamine and 5-hydroxyindoleacetic acid in a concentration- and time-dependent manner. In addition, glutamate induced lactate dehydrogenase leakage. Tetrodotoxin did not block the effects induced by glutamate. MK-801 $(1{\mu}M)$, an N-methyl-D-aspartate (NMDA) channel blocker, but not 6-cyano-2,3-dihydroxy-7-nitro-quinoxazoline $(CNQX;\;3{\mu}M)$, a non-NMDA receptor antagonist, blocked glutamate-induced effects, indicating that these glutamate-induced responses are mediated through NMDA receptors.

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Numerical Analysis of Heat Transfer in Packed Bed of $Ca(OH)_2/CaO$ for Chemical Heat Pump ($Ca(OH)_2/CaO$계 화학 열펌프에 있어서 고체 반응층의 전열해석)

  • Kim, Jong-Shik
    • Solar Energy
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    • v.17 no.1
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    • pp.67-77
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    • 1997
  • To develop chemical heat pump of higher energy density and efficiency heat-release characteristics accompanied by exothermic hydration reaction in packed bed, $Ca(OH)_2/CaO$ reactor, are examined in a lab-scale unit. We have studied the enhancement effect of inserted fins in cylindical packed bed reactor. The results obtained by numerical analysis about profiles of temperature, completion time of reaction and exothermic heat amount released from the reactor read the insertion of fins in reactor can reduce the reaction completion time by half and the rate of thermochemical reaction depends on the temperature and concentration, and it is also governed by the boundary conditions and the rate of heat transfer in the particle packed bed.

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Survey of Models for Random Effects Covariance Matrix in Generalized Linear Mixed Model (일반화 선형혼합모형의 임의효과 공분산행렬을 위한 모형들의 조사 및 고찰)

  • Kim, Jiyeong;Lee, Keunbaik
    • The Korean Journal of Applied Statistics
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    • v.28 no.2
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    • pp.211-219
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    • 2015
  • Generalized linear mixed models are used to analyze longitudinal categorical data. Random effects specify the serial dependence of repeated outcomes in these models; however, the estimation of a random effects covariance matrix is challenging because of many parameters in the matrix and the estimated covariance matrix should satisfy positive definiteness. Several approaches to model the random effects covariance matrix are proposed to overcome these restrictions: modified Cholesky decomposition, moving average Cholesky decomposition, and partial autocorrelation approaches. We review several approaches and present potential future work.

Acute Toxicity of Sodium Chloride, Formaline and Potassium Permanganate to Nile Tilapia Fry (나일틸라피아 치어에 미치는 염화나트륨, 포르말린 및 과망간산칼륨의 금성독성)

  • 박인석;최경철;노재구;김동수
    • Journal of Aquaculture
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    • v.15 no.2
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    • pp.119-121
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    • 2002
  • A study on the acute toxicity in the Nile tilapia, Oreochromis niloticus fry showed that the 24hr-$LC_{50}$ was 18.6% for NaCl,152 ppm for formaline and 2.1 ppm for $KMnO_4$. The fry responded to narrow range of concentration of all the tested chemicals and their toxic effects were dose-dependent.

Steroid Modification with Aspergillus Phoenicis : Effects of Solvents and Glucose (미생물(Aspergillus phoenicis)을 이용한 스테로이드의 변형에 관한 연구 : 유기용매와 포도당의 효과에 관한 고찰)

  • Kim, Mal-Nam
    • The Korean Journal of Mycology
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    • v.11 no.3
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    • pp.115-119
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    • 1983
  • The bioconversion of progesterone by Aspergillus phoenicis has been studied. The metabolism in the conditions of experiment gave $11{\alpha}-hydroxyprogesterone$ as main product. The concentration of $11{\alpha}-hydroxyprogesterone$ increased monotonically and leveled off after 40 hours of incubation. Addition of glucose into the medium reduced considerably the time for attaining limiting concentration of $11{\alpha}-hydroxyprogesterone$. The increase in initial progesterone concentration did not affected the percentage of conversion nor the time required for termination of the reaction. But it could not be represented as first order reaction with respect to progesterone concentration. The degree of inhibition of enzymes by organic solvents depended upon the concentration of solvents. At low solvent concentration, acetone proved to yield the highest conversion.

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3,3'-Diindolylmethane (DIM) decrease adhesion, migration and invasion in human prostate cancer cells (3,3'-Diindolylmethane (DIM)이 인체 전립선암 세포의 부착, 이동 및 침윤성에 미치는 영향)

  • Kim, Hyeon-A
    • Food Science and Preservation
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    • v.22 no.1
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    • pp.19-26
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    • 2015
  • Indole 3-carbinol (I3C), important component of cruciferous vegetables and its major acid-catalyzed metabolite, 3,3'-diindolylmethane (DIM) have been suggested to have an inhibitory effect on the tumor growth and metastasis. This study investigated the effect of DIM on the adhesion, migration and invasion of highly invasive PC3 and DU145 human prostate cancer cell lines. Cells were grown in Dulbecco's modified Eagle's medium (DMEM) supplemented with 3.0 g/L glucose, 3.7 g/L sodium bicarbonate and 10% fetal bovine and were incubated in a humidified incubator at $37^{\circ}C$ and 5% $CO_2$. DIM reduced the adhesion of PC3 and DU145 cells in a dose dependent manner. The pretreatment of PC3 cells with DIM reduced the adhesion dose dependantly, but inhibition was less effective than the treatment with DIM during the adhesion assay. The migration and invasion of PC3 and DU145 cells were reduced by DIM dose dependantly, and the inhibition of DIM was less effective in the DU145 cells than in the PC3 cells. The pretreatment of PC3 cells with DIM for 24 hr before the assay reduced invasion of PC3 cells by 37%. These results suggest that DIM inhibits adhesion, migration and invasion of the PC3 and DU145 cells and may be an effective antimetastatic therapy in addition to traditional chemotherapy.

Effect of Ondansetron Alone and Combination of Naltrexone and Ondansetron on Alcohol Intake in C57BL/6 Mice (Naltrexone과 ondansetron의 병합투여가 C57BL/6형 생쥐의 알코올 섭취량에 미치는 영향)

  • Kim, Hyeun-Kyeung;Kim, Sung-Gon;Kang, Cheol-Joong;Park, Sang-Ick;Kim, Won-Ho
    • Journal of Life Science
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    • v.17 no.11
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    • pp.1576-1581
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    • 2007
  • Dopamine reward pathway projecting from ventral tegmental area to nucleus accumbens is well known as playing an important role in alcohol dependence. It is supposed that this dopamine pathway is modulated by $5-HT_3$ nervous system, and it was reported that ondansetron (OND), $5-HT_3$ receptor antagonist, reduced drinking amount and increased abstinence rate in alcohol-dependent patients. The purpose of this study is to investigate the effect of combination of OND and naltrexone (NTX), non-specific opioid receptor antagonist, on alcohol intake in C57BL/6 mice. In 40 C57BL/6 mice in the state of alcohol dependence, vehicle, while OND 0.01 mg/kg, or NTX 1.0 mg/kg administrated respectively, or OND 0.01 mg/kg and NTX 1.0 mg/kg administrated simultaneously for ten days, medication effects on 2-hr alcohol, 22-hr water, 24-hr food intake and body weight were studied. When vehicle group was compared with 3 medication groups respectively, using a repeated measure ANOVA, NTX alone and vehicle groups showed a significant medication by time interaction (p=0.042) in 2-hr alcohol intake, but in the other 2 groups, OND and NTX combination group and OND alone group, there was no significant interaction with vehicle group in 2-hr alcohol intake. From these results, it is suggested that there is no effect on alcohol intake in mice treating with OND, and naltrexone#s suppression effect on alcohol intake in mice is attenuated when treating with OND and NTX simultaneously. It is supposed that a further study looking at the interactions of serotonin, dopamine and opioid nerves systems will be needed.

Growth Inhibition and Apoptosis Induction of Sulindac on Human Lung Cancer Cells (비소세포 폐암 세포주에서 Sulindac의 성장억제와 세포고사 유도)

  • Kim, Hak Ryul;Yang, Sei Hoon;Jeong, Eun Taik
    • Tuberculosis and Respiratory Diseases
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    • v.56 no.5
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    • pp.514-522
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    • 2004
  • Background : Non-steroidal anti-inflammatory drugs (NSAID) are useful in chemoprevention of colorectal cancers. Continuous NSAID administation causes 40% to 50% reduction in relative risk for colorectal cancer. Sulindac possesses an antiproliferative effect and induces apoptosis and tumor regression on colon cancer and other types of cancers. We intended to analyze the effects of sulindac in three non-small cell lung cancer cell lines. Materials and Methods : The human lung cancer cell lines, A549, NCI-H157 and NCI-H460 were used for this study. Viability was tested by MTT assay, and cell death rate was measured by lactate dehydrogenase(LDH) release. Apoptosis was estimated by flow cytometric analysis and nuclear staining. Results: Sulindac was able to decrease the viability of non-small cell lung cancer cells in a dose- and time- dependent manner. In a parallel effect of sulindac on cell death rate, LDH release was increased in sulindac-treated lung cancer cells. Sulindac significantly increased apoptosis characterized by an increase of $sub-G_0/G_1$ fraction and morphological change of nuclei. The rate of apoptotic cells after sulindac treatment in lung cancer cells increased in a time- and dose- dependent manner in flow cytometric analysis. Apoptotic cells were defined as nuclear shrinkage, chromatin condensation and nuclear fragmentation of cells. Conclusion : Sulindac decreases viability and induces the apoptosis of lung cancer cells. Further studies will be needed to elucidate the potential mechanism of sulindac-induced apoptosis in lung cancer cells.

A Study on establishing a SIS for the efficiency of SCM - based on Power process Methodology - (공급사슬 관리(SCM)의 효율성을 위한 전략정보시스템의 구축에 관한 연구 - 권력순환적 접근을 중심으로 -)

  • Jeon Jae-Woan;Lee Kyung-Hwan
    • Proceedings of the Korea Society for Industrial Systems Conference
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    • 2006.05a
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    • pp.368-385
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    • 2006
  • 본 연구는 효율적인 공급사슬관리(SCM)을 위한 전략 정보시스템 구축에 그 목적이 있다. 이러한 효율적 공급사슬관리를 위한 전략정보시스템 구축에 영향을 주는 요인들을 파워 프로세스의 관점에서 파악하고 이를 실증 연구를 통해 보다 효율적인 전략정보시스템으로서의 SCM 전략의 대안을 제시하고자 한다. 따라서 공급사슬관리의 효율적 운영에 영향을 주는 요인에 관한 영향요인들에 관한 기존 연구와 함께 파워 프로세스의 요소와의 연계를 통해 전략정보시스템으로서의 SCM 전략 유형을 제시하고 이의 특징을 연구의 범위로 설정하고 있다. 이러한 연구의 목적과 연구범위를 위해, 먼저 선행 연구된 파워 프로세스의 권력 주체가 권력요소, 가치 욕구, 환경, 관계성이라는 기본적인 다섯가지 권력 결정변수들간의 동적 상호작용을 통해 새로운 가치를 창출하는 과정을 살펴보며, 이러한 파워프로세스에 의한 전략이 권력 결정변수에 대한 가중치에 의해 전략의 유형이 결정되며, 이 유형에 따르는 전략 효과는 그 가중치와 결정 변수들간의 상호작용에 크게 의존되고 있음을 밝혀내고자 한다. 또한, 공급기업과 공급받는 기업들간의 이러한 관계는 기업이 사용하고 있는 전략적 정보시스템(SIS)으로서의 SCM 전략 유형과 일반적으로 높은 상호작용을 하고 있는 것으로 판단되어지며, 더욱이 기업의 정보가치에 대한 높은 인식으로 인한 디지털 경제하에서의 상호간 전략적 형성을 위해서는 더욱 파워프로세스적 관점하에서 SCM 전략 유형과 전략적 정보시스템간의 통합적으로 고찰함으로써 그 유용성을 살펴볼 수 있고 그러한 결과는 기업성과에 밀접한 영향을 주고 있음을 본 논문에서 밝히고 있다.더십을 행사할 때 이러한 리더십은 경영성과에 긍정적인 결과를 유발하는 것으로 나타났다. 그러므로, 리더십 성과 향상을 위한 지식경영정보시스템은 파워결정요소적 측면에서 고려되어야 할 것이다. 모델과 독립성 모델에서는 시스템 등급에 영향을 준다. 향후에는 더욱 더 다양한 상호의존 모델들이 정량화될 필요성이 있다고 본다. 진행하였다. 줄여서 보다 더 정확하고, 지능적인 규칙구성요소 추출 방법론을 제시하고 구현하여 지식관리자의 규칙습득에 대한 부담을 줄여 주고자 한다. 도움을 받을 수 있게 되었다.을 거치도록 되어있다. 교통주제도는 국가의 교통정책결정과 관련분야의 기초자료로서 다양하게 활용되고 있으며, 특히 ITS 노드/링크 기본지도로 활용되는 등 교통 분야의 중요한 지리정보로서 구축되고 있다..20{\pm}0.37L$, 72시간에 $1.33{\pm}0.33L$로 유의한 차이를 보였으므로(F=6.153, P=0.004), 술 후 폐환기능 회복에 효과가 있다. 4) 실험군과 대조군의 수술 후 노력성 폐활량은 수술 후 72시간에서 실험군이 $1.90{\pm}0.61L$, 대조군이 $1.51{\pm}0.38L$로 유의한 차이를 보였다(t=2.620, P=0.013). 5) 실험군과 대조군의 수술 후 일초 노력성 호기량은 수술 후 24시간에서 $1.33{\pm}0.56L,\;1.00{\ge}0.28L$로 유의한 차이를 보였고(t=2.530, P=0.017), 술 후 72시간에서 $1.72{\pm}0.65L,\;1.33{\pm}0.3L$로 유의한

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A Tumor Growth Inhibitory Substance Isolated from Panax ginseng (고려홍삼분말중의 항종양 활성물질)

  • Katano Mitsuo;Yamamoto Hiroshi;Matsunaga Hisashi
    • Proceedings of the Ginseng society Conference
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    • 1988.08a
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    • pp.33-35
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    • 1988
  • During a series of studies aimed at isolation of the tumor growth inhibitory substance from Panax ginseng. we found a new type of antitumor substance. The substance was isolated from a powder of the root of Panax ginseng C.A. Meyer. which is commonly used for various diseases as a commercial medical drug by the name of Korean Red Ginseng Powder in Japan. Data from infrared spectra proton and carbon-13 nuclear magnetic resonance. and high resolution mass spectra were identical with those of panaxytriol. Panaxytriol isolated from Korean Red Ginseng Powder (Nikkan Korai Ninjin Co.. Ltd.. Japan) inhibited the growth of several kinds of human and murine malignant cells in vitro. Although the detailed mechanism of cell growth inhibition by panaxytriol is yet to he elucidated. panaxytriol's action appeares to be more dose-dependent than time-dependent.

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