• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 추계학술대회
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• pp.517-527
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• 1997

Magnetic Resonance Spectroscopic Imaging is a methodology combining the imaging and spectroscopy. It can provide the spectrum of each areas of image so that one can easily compare the spectrum of one position to another position of the image. In this study, we developed pulse sequence or the spectroscopic imaging method, RF wave forms or the saturation of water signal, computer simulations to validate our method, and confirmed the methodology with phantom experiment. Then we applied the spectroscopic method to human subject and identified a few important metabolites in in vivo. To develope a water saturating RF waveform, we used Shinnar-Le-Roux algorithm and obtained maximum phase RF waveform. With this RF pulse, it could suppress the water signal to 1:1000. The magnet is shimmed to under 1.0ppm with auto-shimming technique. The saturation bandwidth is 80Hz(2ppm). The water and fat seperation is 3.3ppm(about 140Hz at 1 Tesla magnet), the bandwidth is enough to resolve the difference. But we are more concerned about the narrow window in between the two peaks, in which the small quantity of metabolites reside. We performed the computer simulation and phantom experiments in 8*8 matrix form and showed good agreement in the image and spectrum. Finally we applied spectroscopic imaging to the brain of human subject. Only the lipid signal was shown in the periphery region which agrees with the at distribution in human head surface area. The spectrum inside the brain shows the important metabolites such as NAA, Cr/PCr, Choline. We here have shown the spectroscopic imaging which is normally done above 1.5 Tesla machine can be performed in the 1 Tesla Magnetic Resonance Imaging Unit.

• 한국자원식물학회지
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• 제25권4호
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• pp.433-446
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• 2012

기후적인 인자와 양치식물과의 관계를 밝히기 위한 선행연구로서, 우리나라 양치식물 총 321분류군을 대상으로 이들의 생활형에 대하여 휴면형태 및 잎의 계절성을 중심으로 한 분류군별 구성 분석을 수행하여 국내 양치식물의 life-form spectrum을 제시하고자 하였다. 휴면형의 경우, Raunkiaer의 기준으로, 국내 외 표본관의 소장표본 및 전문 연구 자료를 조사하여 구분 정리하였으며, 잎의 계절성에 대하여는 문헌, 개인관찰기록, 개인서신 등에 기초하였다. 아울러 분류 정리된 생활형을 중심으로 각 과별 특성도 살펴보았다. 잎의 계절성 양상에 따른 구분 결과로는 하록성(d), 상록성(e), 동록성(sd)이 각각 37.4%, 59.2%, 1.9%으로 상록성 양치식물이 상대적으로 많이 분포하는 것으로 나타났으며, 분류군별 휴면형에 따라서는 반지중식물(Hemicryptophytes: H)이 42.1%로 가장 높은 비율로 나타났고, 다음으로 지중식물(Geophytes: G)과 착생식물(Epiphytes: E)이 각각 25.5%, 15.9% 이었으며, 지표식물(Chamaephytes: Ch)이 11.8%로 조사되었다. 향후 지역별 식물상에서 양치식물상을 추출하여 유사한 spectrum을 나타내는 지역을 연결한 양치식물 생활형선(Ptph. life-form line)을 도출함으로써 우리나라 양치식물의 분포역 고찰이 가능할 수 있을 것으로 사료된다.

• 생물정신의학
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• 제1권1호
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• pp.17-30
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• 1994

Several different classes of antidepressants(ADs) with newer drugs becoming available have been used for the phamacological management of a broad spectrum of mental disorders, among which depressive disorder is most commonly indicated. Successful clinical use of ADs requires a complete understanding of the psychopharmacological properties of ADs and on accurate knowledge of patients, characteristics based on clinical experience and theoretical framework. This paper aims at providing some practical information on the clinical use of ADs to assist clinicians in treating patients with major depression. The author describes (1) different classes of ADs and their presumed mechanisms of action, (2) clinical characteristics of ADs focusing on side-effect profiles, (3) some issues arising during the treatment course such as : a) pretreatment tasks, b) choice of ADs, c) therapeutic drug dose and monitoring of drug concentration, d) three stages of treatment and e) strategies in refractory depression and (4) ADs in special patient groups.

• BMB Reports
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• 제53권4호
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• pp.181-190
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• 2020

Protein phosphatase 4 (PP4), one of serine/threonine phosphatases, is involved in many critical cellular pathways, including DNA damage response (DNA repair, cell cycle regulation, and apoptosis), tumorigenesis, cell migration, immune response, stem cell development, glucose metabolism, and diabetes. PP4 has been steadily studied over the past decade about wide spectrum of physiological activities in cells. Given the many vital functions in cells, PP4 has great potential to develop into the finding of key working mechanisms and effective treatments for related diseases such as cancer and diabetes. In this review, we provide an overview of the cellular and molecular mechanisms by which PP4 impacts and also discuss the functional significance of it in cell health.

• Korean Journal of Mathematics
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• 제12권1호
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• pp.77-90
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• 2004

The purpose of this paper is to give a sufficient condition for the existence, nonexistence and uniqueness of coexistence of positive solutions to a rather general type of elliptic competition system of the Dirichlet problem on the bounded domain ${\Omega}$ in $R^n$. The techniques used in this paper are upper-lower solutions, maximum principles and spectrum estimates. The arguments also rely on some detailed properties for the solution of logistic equations. This result yields an algebraically computable criterion for the positive coexistence of competing species of animals in many biological models.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1992년도 폐기물 매립지의 공학적 특성과 개량기술
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• pp.1-18
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• 1992

The contaminatlon of soil and groundwater by leachate from impmperly managed landfills, or by cheiicals and gasoline leaked flu underground storage tanks has buou a serious urldwide environmental problei. Most of those contaminants are adsorptive and absorptive into soul, while they are hardly soluble in water. Thus, the rate of self purification is very slow, causing persistent problems in water use and environmental protection when the contamination is left untreated. Biological remediatlon technologies utilize the ertraordlnary caperbllity of microorganisms In degrading a tilde spectrum of organic compounds. Among them, an in situ bioremediation technology Involves injection of supplementary materials into the subsurfce in order to bring about a significant Increase in the microbial activity. The Increased microbial activity helps remove the pollutants in situ, that is, without digging out contaminants, soil, or water. This paper focused on the features, possibilities, and limitations of the bioremedition technology.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2002년도 제9회 학술 발표회 프로그램과 논문초록
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• pp.50-50
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• 2002

The heterologous expression of sodN gene from Streptomyces seoulensis in Streptomyces lividans together with the gel filtration and sedimentation equilibrim data indicated that the quaternary structure of NiSOD is homohexamer, which is novel among SODs, not the previously reported homotetramer. The EPR spectrum of $^{61}$ Ni (I = 3/2) substituted NiSOD showed a clear resolved hyperfine structure at g=2.016, unambiguously identifying that the EPR signal from NiSOD is due to Ni.(omitted)

• 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.253.2-253.2
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• 2002

Apicidin. a natural product HDAC inhibitor. is recently isolated from Fusarium sp. at Merk Research Laboratories, induces therapeutic applications as a broad spectrum antiprotozoal agent to muti-drug resistant malaria and a potential antitumor agent. The biological activity of apicidin appears to be apicocomplexan HDAC at low nanomolar concentrations. (omitted)

• 한국잡초학회지
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• 제31권1호
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• pp.8-23
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• 2011

유기농 재배에서 이용되고 있는 잡초방제 기술 및 연구 동향을 검토하고 앞으로 방향을 제시하기 위하여 화학적 방제를 배제하고 기계적 방제, 경종적 방제, 생물적 방제를 포함한 종합방제 기술에 대한 문헌을 정리하고 분석하여 유기농업에서의 새로운 잡초 관리방안을 전망하고자 하였다. 물리적 방법은 기계적 방법, 열, 광선, 전기충격, 압축공기, 로봇잡초방제기술, 그리고 경종적 방법은 멀칭, 경운, 윤작, 피복식물, 경합을 이용한 방법이 포함된다. 생물적 방제는 미생물제초제, 대량증식 생물제제, 광역 생물제제, 상호대립억제물질 등이 개발되거나 또는 이용되고 있다. 유기농재배에서 성공적인 잡초방제를 위하여 물리적 방법과 경종적 방법은 제초제 사용이 제한된 조건에서 가장 중요한 잡초방제 수단이므로 기계적, 경종적 방법을 근간으로 하고 생물적 방법이 조화롭게 보완되는 종합잡초관리방법이 요구된다. 그리고 유기농 재배에서 수익을 창출하고 적합한 장기적 잡초관리 방안을 도출하기 위하여 잡초관리 결정에 도움이 되는 모델의 개발도 필요하다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2021년도 춘계학술대회
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• pp.59-59
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• 2021

Stachys sieboldii Miq. (SSM) and Acorus gramineus Soland. (AGS) have been used as traditional medicines for thousands of years in parts of Asia, including Korea, China, and Japan. Recent researches on SSM and AGS have documented a wide spectrum of therapeutic properties, including anti-inflammatory, anti-oxidative, neurodegenerative disease effects. However, the toxicity and safety of SSM and AGS, and their mixture (medicinal herber mixture, MHMIX) were not confirmed. Therefore, this study was performed to evaluate the acute toxicity and safety of SSM, AGS and MHMIX. SSM, AGS and MHMIX were orally administered at a dose of 5,000 mg/kg in ICR mice. Animals were monitored for the mortality and changes in the body weight, clinical signs and gross observation during the 14 days after dosing, upon necropsy. We also measured parameters of organ weight, clinical chemistry, and hematology. No dead and no clinical signs were found during the experiment period after administration of a single oral dose of SSM, AGS and MHMIX. There were no adverse effects on clinical signs, body weight, or organ weight and no gross pathological findings in any treatment group. Therefore, LD50 value of SSM, AGS and MHMIX may be over 5,000 mg/kg and it may have no side toxic effect to ICR mice. The results on the single-dose toxicity of SSM, AGS and MHMIX indicate that it is not possible to reach oral dose levels related to death or dose levels with any harmful side effects.