• 한국환경농학회지
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• 제14권3호
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• pp.319-328
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• 1995

잿빛곰팡이병균(Botrytis cinerea)의 procymidone약제 저항성 발현 요인을 구명하기 위하여 procymidone 약제 저항성과 감수성 균주를 각각 세균주씩 선발하여 약제 저항성 검정과 아울러 세포구성물질의 함량 및 조성을 조사한 결과를 요약하면 아래와 같다. 1. 공시균주의 약제 저항성 검정 결과 저항성이 감수성균주에 비하여 1,000배 이상의 저항성이 발현된 것으로 확인되었다. 2. Monooxygenase저해제인 piperonyl butoxide와 esterase 저해제인 triphenyl phosphate를 PDA 배지에 처리한 후 균사생육을 조사한 결과 저항성과 감수성균주간에 차이가 없어 저항성은 균체의 내적요인에서 기인된 것으로 판단되었으며, 아울러 procymidone과 혼합 처리시 약효 상승 효과는 확인되지 않았다. 3. 스테롤 조성은 저항성과 감수성 균주 모두 유사하였으며, GC/MS 분석결과 분자량 428의 스테로이드계 화합물이 비슷한 함량으로 존재하였다. 4. 지질함량은 저항성이 감수성균주에 비하여 30% 정도 많았고, 지방산 함량은 저항성균주의 경우 palmitic acid와 stearic acid가 약 2.5배, oleic acid 2.9배, 그리고 linoleic acid가 공시균주의 주된 지방산으로 나타났으며, 2배 정도 많은 함량을 보였다. 5. 조키틴 함량은 감수성균주가 저항성에 비하여 0.11% 많았으나, 이의 가수분해산물인 N-acetyl glucosamine함량은 저항성균주가 감수성에 비하여 반응 24시간에 3배 그리고 48시간에서 2배 많았다. 따라서 잿빛곰팡이병균(Botrytis cinerea)의 procymidone 약제 저항성은 lipid 함량의 증가, fatty acid 함량의 증가 및 조성의 변화 그리고 키틴 전구물질인 GlcNAc 함량과의 복합적인 요인에 의하여 발현되었을 것으로 판단되었다.

• 한국의류학회지
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• 제20권6호
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• pp.992-1001
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• 1996

The binding of polyethylene glycol (PEG, average molecular weight 600) to cotton fabrics was achieved by using pad-dry-cure process in the presence of citric acid, MgCl3·6H3O, DMDHEU, and TEAHCL. Treated fabrics were dyed with direct, acid, and basic dye. Wrinkle recovery angles, durable press rate, wettability, dyeability and color fastness to washing of all treated cottons were evaluated. The results of this study were as follows: 1. The wrinkle resistance of the PEG treated cottons was increased by increasing PEG and DMDHEU concentration. 2. The wettability of the PEG treated cottons was decreased by increasing PEG and DMDHEU concentration, increased by increasing TEAHCL concentration. 3. PEG/DMDHEU/TEAHCL treated cottons had greater affinity on direct, acid, and basic dye than untreated cottons, and dyeability of the modified cottons was improved compare to untreated fabrics. 4. Color fastness to washing of the PEG/DMDHEU/TEAHCL treated cottons was good except for the wash fastness of the direct dye.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.249-252
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• 2006

Recently, as it has greatly increased the demand on the serviceability of subway, cable tunnel and underground storage, the stability of tunnel structures has been attracting the concern of engineers and researchers. Thus the aim of the present study is to evaluate acid attack resistance of shotcrete using in tunnel structures. And, in order to understand the deterioration mechanism, test using scanning electron microscopy(SEM) analysis and X-ray diffraction showed that the deterioration mechanism due to acid attack in shotcrete.

• Mycobiology
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• 제30권2호
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• pp.88-92
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• 2002

Rehmannia glutinosa is a perennial medicinal plant belonging to the family Scrophulariaceae with more than 300 species known in the world, especially in temperate regions. Its roots have been used widely in Korea for medicinal purposes. However, it is commonly infected by various pathogens during storage, causing great damage to the roots, and impedes the intensive farming of the crop. Therefore, an attempt has been made to isolate and screen a resistance gene against the pathogen Fusarium oxysporum using differential display. We treated salicylic acid(SA), and isolated a resistance gene that responds to SA. As a result, we found that SA was involved in plant defense mechanism in pathogenicity tests with SA treated and non-treted plants, and we isolated a partial PR-la gene through differential display polymerase chain reaction(DD-PCR) method.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.319-323
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• 1999

This study is performed to evaluate the physical and mechanical properties and acid-resistance of oyster shell concrete. The result shows that the unit weights of concrete with oyster shell are decreased by 1∼2% than that of the normla cement concrete. The highest strength is achieved by 2.5% oyster shell filled oyster shell concrete, it is increased compressive strength by 4% , tensile strength by 6% and bending strength by7% than that of the normal cement concrete, respectively . The acid-resistanceis increased with increase of the content of oyster shell. It is 1.6 times of the normal cement concrete by 15% oyster shell filled oyster shell concrete. Accordingly, oyster shell concrete will improve the properties of concrete.

• The Korean Journal of Physiology and Pharmacology
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• 제22권5호
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• pp.493-501
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• 2018

The present study was carried out with the hypothesis that combination of canagliflozin and omega-3 fatty acid may have potential effect on insulin level, insulin resistance, cardiac biomarkers, inflammatory cytokines and histological studies in type 2 diabetes mellitus (DM). Type 2 DM was induced by injecting nicotinamide (120 mg/kg, i.p.) 15 min before STZ (60 mg/kg) injection. Canagliflozin (5 and 10 mg/kg) and omega-3 fatty acid (300 mg/kg) were given for 28 days after confirmation of diabetes. Biochemical estimations revealed elevated levels of glucose, insulin, HOMA-R and inflammatory cytokines in diabetic group. Daily dosing of alone canagliflozin and omega-3 fatty acid slightly reduced elevated levels of glucose, insulin, HOMA-R and inflammatory cytokines ($IL-1{\beta}$, IL-2, and $TNF{\alpha}$), whereas canagliflozin and omega-3 fatty acid combination has reduced these biochemical parameters significantly when compared with diabetic group. Similarly in diabetic group the levels of cardiac biomarkers such as lipid profile, LDH, CKMB and troponin were significantly increased. Elevated levels of cardiac biomarkers were significantly reduced after daily dosing of alone canagliflozin and omega-3 fatty acid. Canagliflozin and omega-3 fatty acid combination has offered better improvement in cardiac biomarkers compared to alone canagliflozin and omega-3 fatty acid. Histopathological analysis also supported the above hypothesis that combination therapy (canagliflozin and omega-3 fatty acid) offered better protection against degenerative changes in ${\beta}-cells$ of pancreas as compared to alone treatment with these drugs. Thus the present study revealed that canagliflozin and omega-3 fatty acid can be used as potential combination therapy in type 2 DM along with cardiac complication.

• 한국식품과학회지
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• 제27권1호
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• pp.101-104
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• 1995

유제품 30여종과 야채발효 제품 2종에서 Lactobacillus casei ssp.(5 strains), Lactobacillus acidophilus(2 strains), Lactobacillus delbrueckii ssp. bulgaricus(6 strains), Lactobacillus plantarum(3 strains), Streptococcus salivarius ssp. thermophilus(11 strains), and Streptococcus faecalis(2 strains)를 각각 분리하여 이들의 내산성과 담즙산 내성을 평가하였다. 초기생균수를 고려하여 공분산분석으로 내산성을 비교한 결과, L. casei에 속하는 균주들의 내산성이 가장 우수하였으며, L. bulgaricus와 균주들은 가장 낮은 내산성을 보였다(p<0.05). 담즙산 내성은 L. casei, L. plantarum, L. acidophilus, S. feacalis 균주들의 경우 비슷한 경향을 보였으나, L. bulgaridus와 S. thermophilus 그룹에 속하는 균주들의 담즙산 내성은 거의 없는 것으로 나타났다.

• 대한미생물학회지
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• 제19권1호
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• pp.11-24
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• 1984

Shigella remains to be an important enteric pathogen in this country for the present. Moreover, most of the isolates have become multiple resistant to various antibiotics which used to be drugs of choice for shigellosis. This study was made as an attempt to assess the present stage of antibiotic resistance and the incidence and transferability of R factors of Shigella. A total of one hundred and seventeen strains of Shigella isolated from patients in Seoul and provincial area between 1982 and 1983 were tested for their resistant to antimicrobial agents and transmission of R-plasmid. Antibiotic susceptibilities were determined by an agar dilution method. Muller hinton agar were used for the assay of drug resistance and tryptic soy broth were used for propagating medium for conjugation. Shigella isolated found to be one or more antibiotics were considered potential donor of R-plasmid. The following results were obtained. 1. Among 117 strains of Shigella isolated, 111 strains(94.9%) were found to be resistant to one or more drugs tested and 97.3% of these resistant strains were multiply resistant, indicating the multiply resistant strains were more than the single resistant strains. Only six strains were susceptible to all drugs tested. 2. Among 117 strains of Shigella isolated, 107 strains(91.5%) were resistant to Tetracyclin(Tc), 106 strains(90.6%) to Chloramphenicol(Cp) and Streptomycin(Sm), 97 strains(82.9%) to Ampicillin(Ap), 68 strains(58.1%) to Cephaloridine(Cr), 10 strains(8.5%) to Nalidixic acid(Na), 5 strains(4.3%) to Kanamycin(Km) and 2 strains(1.7%) to Rifampicin. No strain was resisfant to Amikacin(Ak) and Gentamicin(Gm). 3. All drug-resistant Shigella strains, except three, were multiply resistant to two or more drugs. Fifty eight strains were resistant to five drugs, followed by 26 strains resistant to dour drugs, 12 strains resistant to three drugs and 11 strains resistant to six drugs. 4. The 73% of multiply drug-resistant Shigella transferred their resistance to E. coli by conjugation and the resistance was considered to be mediated by R-plasmid. Resistance to Nalidixic acid and Rifampicin were not transferred by conjugation to recipient. As for the transferability of resistance to each seperate drug, Ap resistance was transferred with 73.2% frequence and Cm and Tc resistance were transferred with approximately 50-60% frequence whereas Sm and Cr resistance were transferred in 19.1-21.4% The other four drugs resistant failed to transfer their resistance to recipient. 5. As for the incidence and transferability of resistance to each seperate drug, the strains resistant to Tc and Cm were encountered most frequently with the rate of 91-92%, whereas transfer of Tc and Cm were low, 51-52%. The incidence of Sm resistance was very high(90.6%) but transferability of drugs resistance was much lower(25.4%). Though the incidence of Km reristance was much lower(4.3%) transferability of Km resistance was considerably higher(60%). 6. The greater the multiplicity of resistance, the greater was the likelihood that part of all of the resistance markers would be transferable.

• 한국치위생학회지
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• 제9권4호
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• pp.740-752
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• 2009

Objectives : This study was carried out to examine the effect of varnish fluoride and APF gel on the acid resistance and the remineralization of the enamel. Methods : At first, the microhardness changes of enamel surface were measured after demineralizing the fluoride treated tooth surface. Next, the changes were measured after fluoride application to the demineralized enamel surface. Results : 1. Acid resistance was higher in varnish fluoride groups than APF gel groups and the difference was significant(p<0.001). 1) Varnish fluoride groups Microhardness of enamel surface showed $297.76{\pm}9.89$ after fluoride treatment and $260.90{\pm}28.67$ after drmineralization. The changes of Vickers hardness number(VHN) were $-36.86{\pm}27.30$. 2) APF gel groups Microhardness of enamel surface showed $298.79{\pm}17.28$ after fluoride treatment and $43.75{\pm}18.58$ after demineralization The changes of VHN were $-255.04{\pm}21.31$. 2. No significant changes were surveyed in both varnish fluoride groups and APF gel groups as for remineralization of enamel(p>0.05). 1) Varnish fluoride groups Microhardness of enamel surface showed $46.58{\pm}15.42$ after demineralization and $46.61{\pm}15.70$ after fluoride treatment. The changes of VHN were $0.02{\pm}3.75$. 2) APF gel groups Microhardness of enamel surface showed $47.13{\pm}19.31$ after demineralization and $42.59{\pm}16.12$ after fluoride treatment. The changes of VHN were $-4.54{\pm}5.06$. Conclusions : Varnish fluoride showed higher acid resistance than APF gel, however both of them were observed to have no effect on the remineralization of the enamel.

• 한국미생물·생명공학회지
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• 제31권3호
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• pp.297-300
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• 2003

In order to select probiotics with a high survival rate in gut and the growth inhibition of virulent pathogens to human beings or animals, we have screened lactic acid bacteria and yeasts from Jeot-gal to assess resistance against the artificial gastric acid and bile juice. Lactic acid bacteria and yeasts isolated were incubated for 24 h in artificial bile juice after incubation for 2 h in artificial gastric acid. Especially, strain HW 161 and strain NK 181 showed the higher survival for 2 h incubation in artificial gastric acid. All of 3 strains of lactic acid bacteria and 2 strains of yeast were showed higher growth rate than the control in artificial bile. The antimicrobial activity of lactic acid bacteria and yeasts was also investigated to prove efficacy as probiotic organisms. Lactic acid bacteria were shown the inhibition of Gram positive and negative bacteria, but yeasts narrow inhibition.