• Biomolecules & Therapeutics
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• 제6권2호
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• pp.139-144
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• 1998

Abstract -Phyllanthus ussuriensis which belongs to Euphorbiaceae has been used as a component of Korean traditional remedy against hepatitis and jaundice. Aqueous methanolic extract of P. ussuriensis was tested for antiviral activity of hepatitis B virus (HBV) in HepG2 2.2.15 cells which were derived through transfection of cloned HBV DNA into HepG2 human hrpatoblastoma cells. P. ussuriensis extract decreased the levels of extracellular HBV virion DNA and inhibited HBV replication at concentrations ranging from 50 to 500$\mu$g/ml. Partitioning of water suspension of the extract revealed that the activity mainly resides in the EtOAc fraction. Consecutive purification of the EtOAc fraction by silica-gel column chromatography resulted in the two active anti-HBV fractions. Southern blot analysis shows that the action mechanisms or active site of the two fractions seems to be different in terms of their inhibition of HBV replication steps.

• 한국측량학회지
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• 제36권3호
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• pp.177-184
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• 2018

In case that limited resources can be mobilized, non-structural countermeasures such as 'monitoring using Information and Communication Technology might be one of solutions to mitigate disaster risks. Having established the monitoring system, operational and maintenance costs to maximize the effectiveness might trouble the authority concerned or duty attendant who is in charge. In this respect, "Guerrilla Sensor" would be very cost effective because of the inherent mobility characteristic. The sensor device with the IRIS camera and GPS (Global Positioning System) equipped, is basically battery-operated and communicates with WCDMA (Wideband Code Division Multiple Access). It has a strong advantage of capabilities for 'Disaster Response' with immediate and prompt action on the spot, making the best use of IoT (Internet of Things), especially with the mobile web. This paper will explain how the sensor system works in real-time GIS (Geographic Information System) pinpointing the exact location of the abnormal movement/ground displacement and notifying the registered users via SMS (Short Message Service). Real time monitoring with early warning and evaluation of current situations with LBS (Location Based Service), live image and data information can help to reduce the disaster impact. Installation of Guerrilla sensor for a real site application at Gimcheon, South Korea is also reported.

• Journal of Photoscience
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• 제7권3호
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• pp.87-95
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• 2000

As sunlight not always optimized for every terrestrial plant in terms of light quality, quantity and duration, some plants suffer detrimental effects of sunlight exposure under certain conditions. Photoinhibition of photosynthesis is a typical phenomenon representing harmful light effects, commonly observed in many photosynthetic organisms. It is generally accepted that functional, structural loss of photosystem II complex(PSII) is the primary event of photoinhibition. Accumulating data also suggest that singlet oxygen($^1$O$_2$) is the main toxic species directly involved in it. There are two different views on the specific site and mechanism of $^1$O$_2$ production in the photosynthetic membrane. One of them favors the PSII reaction center, where the primary charge pairs recombination occurs as a prerequisite for the generation of $^1$O$_2$, and the other inclines to photosensitized $^1$O$_2$ formation by a substance located outside PSII. This article describes how we, as the advocators of the latter concept, have arrived at the conclusion that $^1$O$_2$ immediately involved in PSII photodamage is largely generated from the Rieske center of the cytochrome b$_{6}$/f complex and diffuses into PSII, attacking the reaction center subunits.s.

• 한국잡초학회지
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• 제9권3호
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• pp.230-237
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• 1989

Bleaching herbicides(oxyfluorfen, oxadiazon, paraquat)의 작용발현에 영향을 미치는 온도 및 광의 효과를 조사한 결과 oxyfluorfen 과 oxadiazon의 제초활성은 $10-35^{\circ}C$에서 온도가 증가될수록 높았으며 온도의 효과는 제초작용 발현단계(photooxidation) 보다는 그 이전 단계에서 더욱 큰 영향이었다. 처리약제 모두 광도가 높을수록 활성이 강하였으며 paraquat 는 광질간의 활성차이가 없었으나 oxyfluorfen 및 oxadiazon 은 챙색광에서 높은 활성을 보였고 이들 두 약제에 대한 광의 효과는 광합성 및 호흡의 전자전달계나 carotenoid 생합성 보다는 chlorophyll 생합성 과정과 일정한 관련이 있다.

• 대한한의학회지
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• 제23권1호
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• pp.50-60
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• 2002

Objectives: Sunghyangjunggisan (SHJS) is a commonly prescribed drug with a wide neuropharmacological spectrum. The water extracts of SHJS were found to be protective against neurotoxicity elicited by deprivation of serum and glucose. Methods: The morphological examination and Hoechst staining of nucleus also clearly showed that the extracts attenuated the cell shrinkage, membrane blebbing, representing typical neuronal apoptotic phenomena and nucleosome-sized fragmentation under the microscope in PC 12 rat pheochromocytoma cells. Results: Activation of protein kinase A (PKA) with dibutyl-cAMP and forskolin also protected during glucose deprivation, although it was not additive with the effect provided by phorbol ester. Interestingly, treatment with the protein kinase A inhibitor, KT5720, was not neuroprotective in the presence of SHJS. Electrophoretic mobility shift assays were used to characterize the neuroprotective binding of nuclear proteins to consensus sequences for AP-l, nuclear factor kappa B ($NF-{\kappa}B$) after glucose deprivation. When PC 12 cells are induced to undergo apoptosis by serum deprivation, AP-l and $NF-{\kappa}B$ DNA binding activity transiently increases to a slight degree. This stimulation is blocked by the water extracts of SHJS. The site of action of the drugs appeared to involve specific inhibition of AP-1 and nuclear factor kB binding activity. Conclusions: Taken together, these results suggested the possibility that the extracts of SHJS might provide a neurotrophic-like activity in PC 12 cells.

• The Korean Journal of Pain
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• 제26권1호
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• pp.65-71
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• 2013

More than 80% of cancer patients experience cancer pain. Among them, more than 50% experience moderate to severe pain. To control cancer pain, a variety of methods have been used, including medications and nerve blocks. In some patients, however, it is impossible to perform nerve blocks due to caner metastasis into the epidural space, while in other patients, opioid dose escalation is impossible due to opioid side effects; thus, cancer pain management is difficult. Scrambler therapy is a novel approach for pain control that uses EKG-like pads, which are applied above and below the site of pain. Scrambler therapy synthesizes 16 different types of nerve action potentials that provide "non-pain" information via cutaneous nerves. The advantages of this treatment are that it is non-invasive and safe and has no significant side effects. In this case series, we report the treatment results of using scrambler therapy in three cancer patients with intractable pain.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제6권1호
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• pp.21-26
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• 2006

In this paper, we propose a customer personalized system that presents the web pages to users which are customized to their individuality. It analyzes the action of users who visit the shopping mall, and preferentially supplies the necessary information to them. When they actually buy some items, it forecasts the user's access pattern to web site and their following purchasable items and improves their web page on the bases of their individuality. It reasons the relation among the web documents and among the items by using the log data of web server and the purchase information of DB. For reasoning, it employs Apriori algorithm, which is a method that searches the association rule. It reasons the web pages by considering the user's access pattern and time by using the web log and reasons the user's purchase pattern by using the purchase information of DB. On the basis of the relation among them, it appends the related web pages to link of user's web pages and displays the inferred goods on user's web pages.

• The Korean Journal of Pain
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• 제27권3호
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• pp.200-209
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• 2014

Background: Spinal opioid administration is an excellent option to separate the desirable analgesic effects of opioids from their expected dose-limiting side effects to improve postoperative analgesia. Therefore, physicians must better identify either specific opioids or adequate doses and routes of administration that result in a mainly spinal site of action rather than a cerebral analgesic one. Methods: The purpose of this topical review is to describe current available clinical evidence to determine what opioids reach high enough concentrations to produce spinally selective analgesia when given by epidural or intrathecal routes and also to make recommendations regarding their rational and safety use for the best management of postoperative pain. To this end, a search of Medline/Embase was conducted to identify all articles published up to December 2013 on this topic. Results: Recent advances in spinal opioid bioavailability, based on both animals and humans trials support the theory that spinal opioid bioavailability is inversely proportional to the drug lipid solubility, which is higher in hydrophilic opioids like morphine, diamorphine and hydromorphone than lipophilic ones like alfentanil, fentanyl and sufentanil. Conclusions: Results obtained from meta-analyses of RTCs is considered to be the 'highest' level and support their use. However, it's a fact that meta-analyses based on studies about treatment of postoperative pain should explore clinical surgery heterogeneity to improve patient's outcome. This observation forces physicians to use of a specific procedure surgical-based practical guideline. A vigilance protocol is also needed to achieve a good postoperative analgesia in terms of efficacy and security.

• Archives of Pharmacal Research
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• 제21권6호
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• pp.671-676
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• 1998

Five hundred and seventy clinical strains of Pseudomonas aeruginosa were isolated from August 1993 to August 1994 in Korea and screened for their resistance to ciprofloxacin, norfloxacin, and ofloxacin. Among these, two P. aeruginosa strains (PA150 and PA300) were selected based on their strong resistance (MICs > 50mcg/ml) to all three quinolones. The susceptible strain as well as two resistant strains had proton gradient-dependent efflux system. Efflux system in PA300 showed different specificities to ofloxacin and ciprofloxacin while PA150 had less permeability for ofloxacin. Ofloxacin had a less inhibitory action on DNA synthesis in permeabilized cells of PA150 and PA300 than 1771M. When quinolone resistance determining region (QRDR) in gyrA was sequenced, PA300 had one missense mutation, Asn 116Tyr, which was newly reported in this work. The results showed that PA150 became ofloxacin resistant by reduced ofloxacin accumulation due to the existence of efflux system and low permeability, while resistance of PA300 was due to the efflux system and a mutation in QRDR of gyrA -the target site of quinolone.

• 한국식품과학회지
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• 제5권3호
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• pp.157-162
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• 1973

무균(無菌) 상태하에서 습윤한 여지위에 숙성(熟成)시킨 감자 괴경 박편(塊莖 薄片) $(1mm{\times}1.5cm)$을 재료로 방사선(放射線)의 작용기작(作用幾作)연구를 행하였다. Invertase, 핵산 및 호흡작용의 time courses를 결정하고 이들 세작용의 방사선(放射線)에 대한 민감도를 측정하였다. 세 작용 중 어느 것도 세포분열을 억제하는 선량에서 심하게 억제되지 않았다. $^3H-thymidine$의 incorporation 결과는 방사선(放射線)의 작용부위가 mitosis나 $G_2$ period에 존재할지도 모른다는 것을 암시한다.