• Applied Biological Chemistry
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• v.26 no.1
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• pp.35-40
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• 1983

The inhibitory activity of 20 Lactic strains from Kimchi was tested against Escherichia coli and other microorganisms. Of the lactic strains investigated, A7 (Pediococcus cerevisiae) and C4(Leuconostoc spp.) were the most effective in restricting the growth of test organisms. The mixed culture inoculation of each selected lactic strain and Escherichia coli resulted in a drastic reduction in the plate count of Escherichia coli after 24 hours. Similar results were obtained when Staphylococcus aureus and Bacillus cereus were used as test organisms. For all test organisms, the presence of A7 caused a higher death rate constant than that of C4. Addition of catalase in the mixed culture did not prevent inhibition, suggesting that hydrogen peroxide did not cause the inhibition. The filtrate of A7 culture added to Escherichia coli showed identical inhibitory action, however heat treatment of filtrate at $80^{\circ}C$ 30min. destroyed the inhibitory activity. A7 filtrate treated with trypsin substantially lost the inhibitory effect, but not by pepsin. The results imply that the protein-like compound(s) is the principal inhibitor produced by this lactic strain.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.4
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• pp.662-667
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• 2001

Some biological activities and isoflavone (daidzein, genisten) contents were investigated from chungkugjang (CK) fermented with black beans and Bacillus strains at 42$^{\circ}C$ for 72 hr. n antibacterial activity, black bean CK fermented with Bacillus megaterium SMY-212 was higher than that ferment4d with B. subtilis. In both CK the methanol extract fo large black bean CK was more effective than that of small black bean CK was more effective than that of small black bean. Hydrogen-donating activity of methanol extract of chungjugjang (MEC) prepared with large and small black soybean showed to be 76.4 and 75.5%, respectively. Hydrogen-donating activity of MEC prepared with B. subtilis and SMY-212 was slightly highter than that without both strains. MEC of large black bean was higher in nitrite-scavenging activity than that of small black bean, and black bean CKs fermented with B. subtilis and SMY-212 have no difference in nitrite-scavenging activity B. subtilis and SMY-212. MEC of black bean showed strong antioxidative activity against peroxidation of linoleic acid and $H_2O$$_2$-FeSO$_4$-induced peroxidation of rat liver homogenate. MEC of black bean with Bacillus strains was higher in antioxidative activities than that of black bean without Bacillus strains. Contents of isoflavone (daidzein, genistein) were gradually increased during fermentation of CK. The isoflavone content was slightly higher in large black bean CK than in small black bean CK.

• Tuberculosis and Respiratory Diseases
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• v.45 no.2
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• pp.457-464
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• 1998

This report describes a 5-month follow-up of the efficacy of Herbst oral appliance(OA) in a obstructive sleep apnea syndrome patient who has failed with uvulopalatopharyngoplasty(UPPP) and was unable to tolerate to subsequent nasal continuous positive airway pressure(CPAP) because of mouth air leak. The obstructive sleep apnea and daytime performance were markedly improved by regular home use of OA, and the patient still continues to use OA without complications. It is suggested that OA can be a successful alternative therapeutic modality in patients who are unable to tolerate to nasal CP AP, especially after UPPP.

• Tuberculosis and Respiratory Diseases
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• v.45 no.2
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• pp.429-436
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• 1998

Approximately 100 drugs have been reported to affect the lungs adversely. Among these, pulmonary toxicity caused by antieneoplastic agent. is being recognized more frequently. Cyclophosphamide is an immunosuppressive alkylating agent used for the treatment of a wide variety of malignant and nonmalignant diseases. The incidence of pulmonary toxicity is probably less than 1 percent The first case was reported in 1967. Since then, more than 20 well-documented cases of pulmonary toxicity associated with cyclophosphamide have been reported in the literature. In Korea, three patients were identified with cyclophosphamide-induced lung disease. The typical features of toxicity include dyspnea, fever, cough, new parenchymal infiltrates, gas exchangs abnormalities on pulmonary function tests, and pleural thickening on chest roentgenogram. The best approach to management is early diagnosis, discontinuation of the offending drug and administration of corticosteroid therapy. Recently, we experienced a case of diffuse alveolar damage induced by cyclophosphamide. The patient presented with early-onset pulmonary toxicity and died of repiratory failure despite early use of corticosteroid.

• Restorative Dentistry and Endodontics
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• v.34 no.6
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• pp.467-476
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• 2009

The aim of this study was to measure the dentinal tubular fluid flow (DFF) during and after amalgam and composite restorations. A newly designed fluid flow measurement instrument was made. A third molar cut at 3 mm apical from the CEJ was connected to the flow measuring device under a hydrostatic pressure of 15 $cmH_2O$. Class I cavity was prepared and restored with either amalgam (Copalite varnish and Bestaloy) or composite (Z-250 with ScotchBond MultiPurpose: MP, Single Bond 2: SB, Clearfil SE Bond: CE and Easy Bond: EB as bonding systems). The DFF was measured from the intact tooth state through restoration procedures to 30 minutes after restoration, and re-measured at 3 and 7days after restoration. Inward fluid flow (IF) during cavity preparation was followed by outward flow (OF) after preparation, In amalgam restoration, the OF changed to IF during amalgam filling and slight OF followed after finishing. In composite restoration, application CE and EB showed a continuous OF and air-dry increased rapidly the OF until light-curing, whereas in MP and SB, rinse and dry caused IF and OF, respectively. Application of hydrophobic bonding resin in MP and CE caused a decrease in flow rate or even slight IF. Light-curing of adhesive and composite showed an abrupt IF. There was no statistically significant difference in the reduction of DFF among the materials at 30 min. 3 and 7 days after restoration (p > 0.05).

• Journal of Dairy Science and Biotechnology
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• v.32 no.2
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• pp.141-145
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• 2014

There is a burgeoning number of products on the market that contain probiotics, but do they do you any good? What exactly are probiotics? They have been defined as living organisms that, when ingested in sufficient quantities, provide health benefits beyond basic nutrition. They are often referred to as "friendly bacteria" or "good bacteria." Probiotics have been claimed, amongst other things, to (i) reduce the incidence of colon cancer and other diseases of the colon, such as IBS, (ii) stimulate the immune system, (iii) have anti-hypertensive and anti-cholesterolemic properties, (iv) mitigate against the effect of antibiotics on the intestinal microbiota, and (v) protect against gastrointestinal infections. However, the scientific basis for many of these claims is not well-established. Indeed, the European Food Safety Authority has denied the use of several health claims associated with probiotics, particularly those related to mitigation of diarrhea following consumption of antibiotics. Thus, there is a need for research on the mechanisms of action of probiotics. We have been mainly interested in the use of probiotics to control enteric infections. There are several possible modes of action to explain how probiotics may protect the host from enteric pathogens, including competitive exclusion and immunomodulation. We have shown that probiotics produce bioactive molecules that interfere with bacterial cell-cell communication (also called quorum sensing), and this results in a down-regulation of virulence genes that are responsible for attachment of the pathogen to the gastrointestinal epithelium. These bioactive molecules act on a variety of bacteria, including enterohemorrhagic and enterotoxigenic Escherichia coli, Salmonella, Clostridium difficile and Clostridium perfringens, and there is evidence that they can inhibit the formation of biofilms by Listeria monocytogenes. These bioactive molecules, which are peptidic in nature, can exert their effects not only in vitro but also in vivo, and we have shown that they mitigate against E. coli O157:H7 and Salmonella in mice and Salmonella and E. coli K88 infections in pigs. They can be delivered in foods such as yoghurt and maintain their activity.

• The Korean Journal of Pesticide Science
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• v.4 no.3
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• pp.7-14
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• 2000

Methanol extracts from 21 grains were tested for fungicidal activities against six phytopathogenic fungi and for insecticidal activities toward five insect pests in a greenhouse. The efficacy varied with both the plant pathogen/insect pest and grain species used. Potent fungicidal activity at 5 mg/pot, were produced from extracts of Elymus sibiricus and Hordeum vulgare var. nudum against Pyricularia grisea and Erysiphe graminis and these of Sesamum indicum (W) and Triticum aestivum against Puccinia recondita and Erysiphe graminis. At 2,500 ppm, potent insecticidal activities were exhibited from the extracts of Fagopyrum esculentum against Myzus persicae and Ischaemum crassipes, and these of Oryzo sativa var. glutinosa, Panicum miliaceum, Setaria italica, Sorghum bicolor, and T. aestivum against Tetranychus urticae. All grain extracts revealed weak or no fungicidal and insecticidal effect against Phytophthora infestans, Plutella xylostella and Spodoptera litura. As a naturally occurring fungicide and insecticide, grain-derived materials described could be useful as new fungicidal and insecticidal products against phytopathogenic fungi and insect pests.

• Restorative Dentistry and Endodontics
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• v.35 no.5
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• pp.313-320
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• 2010

Objectives: The aim of this study was to examine changes in the dentinal fluid flow (DFF) during desensitizing agent application and to compare permeability after application among the agents. Materials and Methods: A Class 5 cavity was prepared to exposure cervical dentin on an extracted human premolar which was connected to a sub-nanoliter fluid flow measuring device (NFMD) under 20 cm water pressure. DFF was measured from before application of desensitizing agent (Seal&Protect, SP; SuperSeal, SS; BisBlock, BB; Gluma desensitizer, GL; Bi-Fluoride 12, BF) through application procedure to 5 min after application. Results: DFF rate after each desensitizing agent application was significantly reduced when compared to initial DFF rate before application (p < 0.05). SP showed a greater reduction in DFF rate than GL and BF did (p < 0.05). SS and BB showed a greater reduction in DFF rate than BF did (p < 0.05). Conclusions: Characteristic DFF aspect of each desensitizing agent was shown in NFMD during the application procedure.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.346-346
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• 2007

압전세라믹 재료는 현재 압전 변압기, actuator, transducer, sensor, speaker 등에 광범위하게 이용이 되고 있다. 이 중에서 압전세라믹 소결체를 이용한 스피커의 제조는 가공이 까다롭고, 대형의 크기로 제작 시 소자가 깨지는 등의 많은 제약을 받고 있으며, 저음 특성이 떨어져 응용 범위가 한정되어 있다. 따라서 최근에는 이러한 단점을 극복하기 위하여 세라믹/고분자 복합체를 이용한 필름 스피커를 제작하고자 시도하고 있다. 이러한 세라믹/고분자 0-3형 압전 복합체를 이용할 경우, 제품의 경량화를 실현할 수 있고, 크기나 환경의 영향을 거의 받지 않으므로, 고기능성 스피커로의 응용에 적합할 것으로 보인다. 따라서 본 연구에서는 PZT계의 세라믹와 PVDF, PVDF-TrFE, Polyester, acrylic resin 등의 여러 고분자 물질과의 복합체를 제조하여 압전특성을 평가하였다. 본 실험은 먼저 $(Pb_{1-a-b}Ba_aCd_b)(Zr_xTi_{1-x})_{1-c-d}(Ni_{1/3}Nb_{2/3})_c(Zn_{1/3}Nb_{2/3})_dO_3$ (이하 PZT라 표기)의 최적화 조성을 선택하여, $1050^{\circ}C$에서 소결된 분말을 48시간 ball milling방법 로 약 $1{\mu}m$ 크기로 분쇄하였다. 고분자 물질들은 알맞은 용제들을 선택하여 녹였다. 그 다음 소결된 PZT분말과 고분자를 50:50, 60:40, 65:35, 70:30등의 무게 분율로 혼합하고, 분산제, 소포제 등을 첨가하여 3단 roll mill을 이용하여 충분히 분산시켜 페이스트 (Paste)를 제조하였다. 제조된 페이스트를 ITO가 코팅된 PET필름 위에 스크린 프린팅 법을 사용하여 인쇄하여 $120^{\circ}C$에서 5분간 건조하였다. 코팅된 복합체의 두께는 약 $80{\mu}m$ 정도로 측정되었다. Ag 페이스트를 이용한 상부 전극 형성에도 스크린 프린팅 법을 적용하였다. 이를 $120^{\circ}C$에서 4 kV/mm의 DC 전계로 분극 공정을 수행한 후 전기적 특성을 평가하였다. 유전특성을 조사하기 위해서 LCR meter (EDC-1620)를 사용하였고, 시편의 결정구조는 XRD (Rigaku; D/MAX-2500H)을 통해 분석하였으며, 전자현미경(SEM)을 이용하여 미세구조를 분석하였다. 압전 전하상수$(d_{33})$ 값은 APC 8000 모델을 이용하여 측정하였다. PZT의 혼합비가 증가할수록 비유전율 및 압전 전하 상수 등의 전기적 특성이 증가되었다. 또 여러 고분자 물질 중에서 PVDF-TrFE 수지가 가장 우수한 특성을 보였다. 이는 PVDF-TrFE 수지가 압전성을 나타내기 때문인 것으로 판단되었다.

• Korean Journal of Weed Science
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• v.7 no.2
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• pp.236-242
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• 1987

The study was conducted to interprete the fluctuation of weed vegetation in plant-sociological impacts as affected by the mixture use of oxyfluorfen and glyphosate with various dosages. Also, intended to know the real interaction between two herbicides in weeding efficacies. The better efficacy from the above mixture was recognized than from the oxyfluorfen + paraquat mixture on the perennial-sites. In lower rate mixture of oxyfluorfen, the dominance index was increased by the annual grass species (ie. Digitaria), and of glyphosate by the biennial Stellaria and perennial species (ie. Artemisia). Also, the positive maximum action of both oxyfluorfen and glyphosate in various mixture rates was categorized upto 0.55kg ai/ha for oxyfluorfen and 0.35kg ai/ha for glyphosate, respectively. However, the interaction between the above two herbicides recognized actually as negative. Consequently, the use of mixture compound of oxyfluorfen with glyphosate are expected rather to promote the control efficacy of specific weed species, to enlarge the weeding spectrum and to prolong the weeding periods than to reduce the application rate of both chemicals depending on any synergic interactions.