• Restorative Dentistry and Endodontics
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• 제9권1호
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• pp.59-68
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• 1983

The purpose of this study was to examine the influence of canal irrigants and the method of canal filling on the quality of canal obturation. Sixty extracted human teeth with single root were selected and divided into three different groups; In group I (control); 5 cc normal saline irrigated after each instrumentation In group II; 2.5 cc-3% NaOCl in combination with 2.5 cc-3% $H_2O_2$ In group III; RC-Prep in combination with 5 cc-3% NaOCl All specimens were cleaned, shaped(#50 file size), irrigated and obturated by lateral condensation and automated thermatic condensation filling method of gutta-percha and AH-26. After all the specimens were immersed in 2% methylene blue dye solution in $37^{\circ}C$ for 7 days and the degree of dye penetration into the canals observed by magnifying glass(${\times}$20) and reflected light microscope The results were as follows: 1. All the the teeth showed some degree of the dye penetration. 2. There were no significant difference among three groups in the degree of the dye penetration in each canal filling method. 3. There were no significant difference of the dye penetration between each canal filling method in group I. 4. There were no statistically significant difference of the dye penetration between each canal filling method in group II and group III, but lateral condensation group was showed slightly more than automated thermatic condensation group.

• Journal of the Korean Wood Science and Technology
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• 제41권4호
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• pp.269-275
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• 2013

본 연구는 유기질 문화재 보존을 위해 한국 전통 약용식물을 대상으로 항균 및 살충활성을 검증한 결과 황벽나무 열매 추출물이 우수한 활성을 나타냄을 확인하였다. 황벽나무 열매 추출물을 비극성 용매로 분획하여 그 중 가장 활성이 우수한 ethylacetate 분획물을 대상으로 실리카젤 및 Sephadex LH-20 컬럼 크로마토그래피를 실시하고 Prep-TLC를 이용하여 화합물을 순수 분리하였다. 화합물은 UV spectrum 분석 결과 260 nm 파장에서 최대흡수피크가 관찰되었고, $^1H$, $^{13}C$, HMQC, HMBC NMR과 ESI mass spectrum을 이용하여 화학구조를 분석한 결과 (4'-ethyl-2'-methylfuranyl)-6-methoxy-7-methylnona-2E,4E,6Z,8E-tetraenoic acid의 새로운 화합물임을 알 수 있었다.

• 한국작물학회지
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• 제56권4호
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• pp.349-360
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• 2011

The objectives of present study were to characterize the peptides which were isolated from Korean fermented soybean paste, chungkukjang, and to determine their antioxidant activities. Four fractions were collected from the methanol extract of chungkukjang by using a recycling preparative HPLC. Among fractions, Fr-2 was identified to be highly potent free radical scavenging activity in the assay of 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and nitroblue tetrazolium(NBT)-reduction inhibition. Base on antioxidant effects, fraction Fr-2 was employed for the refraction with a prep-column and separated into five fractions of which two fractions were identified to have higher antioxidant activity. To confirm the amino acid constituents of antioxidant fractions Fr-2-2 and Fr-2-3 were analyzed, and eight kinds of amino acids such as aspartic acid, threonine, serine, glutamic acid, glycine, lysine, histidine, and arginine were identified as the constituent amino acids. Antioxidant activities of the separated peptides were further assessed cell viability with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl terazolium bromide (MTT), and fluorescence-activated cell sorting (FACS) analysis of H4IIE cells treated with hydrogen peroxide (H2O2). Chungkukjang peptides have shown their ability to protect H4IIE rat hepatoma cells against H2O2- induced oxidative stress by concentration and time-dependent manner. Therefore, These results indicated that fermented soybean paste chungkukjang will be promoted the antioxidant and radical scavenging activities, and beneficial for health. The antioxidant peptide fractions Fr-2-2 and Fr-2-3 were denominated as P-NICS-1 and P-NICS-2, respectively. However, further studies were required to clarify their amino acid sequences and molecular properties, and physiological significances.

• Journal of Microbiology and Biotechnology
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• 제15권5호
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• pp.1001-1010
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• 2005

Bacillus megaterium KL39, an antibiotic-producing plant growth promoting rhizobacterium (PGPR), was selected from soil. The antifungal antibiotic, denoted KL39, was purified from culture filtrate by column chromatography using Dion HP-20, Silica gel, Sephadex LH-20, and prep-HPLC. Thin layer chromatography, employing the solvent system of ethanol:ammonia:water=8:1:1, showed the $R_{f}$. value of 0.32. The antibiotic KL39 showed a negative reaction with ninhydrin solution, positive with iodine vapor, and also positive with Ehrlich reagent. It was soluble in methanol, ethanol, butanol, and acetonitrile, but insoluble in chloroform, toluene, hexane, ethyl ether, or acetone. Its UV spectrum had the maximum absorption at 208 nm. Amino acid composition, FAB-mass, $^{1}H-NMR,\;^{13}C-NMR$, and atomic analyses showed that the antibiotic KL39 (MW=1,071) has a structure very similar to iturin E. The antibiotic KL39 has a broad antifungal spectrum against a variety of plant pathogenic fungi including Rhizoctonia solani, Pyricularia oryzae, Monilinia froeticola, Botrytis cinenea, Altenaria kikuchiana, Fusarium oxysporum, and F. solani. An MIC value of $10\;{\mu}g/ml$ was determined for Phytophthora capsici. Macromolecular incorporation studies with P. capsici using radioactive [$^{3}H-adenine$] as the precursor, indicated that the antibiotic KL39 strongly inhibits the DNA biosynthesis of the fungal cell. Microscopic observation of the antifungal action showed abnormal hyphal swelling of P. capsici. The purified antibiotic KL39 was very effective for the biocontrol of in vivo Phytophthora-blight disease of pepper.

• 대한본초학회지
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• 제21권2호
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• pp.1-7
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• 2006

Objectives : The purpose of this study is to isolate tyrosinase inhibitory material from Pinellia ternata and characterize its own structure and activity. Methods : Pinellia ternata (600g) was extracted with 95% methanol (1L) at $37^{\circ}C$ for 4 days, with shaking at 250rpm. The extract was further solvent-fractionated with n-hexane, chloroform, ethylacetate and water. The active fraction was subjected to JAI recycling prep-HPLC JAIGEL GS-320 column. The structure was identified for the active peak with NMR and GC. Results : Tyrosinase was potently inhibited by 95% methanol extracts from Pinellia ternata. The $IC_{50}$ value of the extracts was estimated to be 0.05mg/ml. The extracts was divided into four solvent-fractions, and the most potent tyrosinase inhibition was found in ethylacetate layer. $IC_{50}$ value of ethylacetate fraction was 0.001mg/ml. This fraction was further purified with JAI Recycling Preparative HPLC (Model: LC 9104). The isolated compound showing inhibitory activity was characterized on its chemical structure by NMR and the compound was identified as 3,4-dihydroxybenzaldehyde. $IC_{50}$ was found to be 7.74 ${\mu}M$ which is much lower than that of kojic acid $(66.5{\mu}M)$. Conclusions : The data suggest that 3,4-dihydroxybenzaldehyde isolated and identified from Pinellia ternata is very strong inhibitor to melanin biosynthesis.

• 벤처창업연구
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• 제5권1호
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• pp.19-44
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• 2010

본 연구에서는 창업교육이 예비창업자의 심리적 특성 변화에 미치는 영향을 분석하는데 연구의 목적을 두고자 한다. 다시 말하면, 창업자의 심리적 특성이 창업교육을 받은 전과 수료 후 어떤 변화가 있는지에 대한 연구이다. 창업자의 심리적 특성으로는 기존 선행연구에서 주로 통제의 위치, 위험감수성향, 성취욕구, 모호성의 수용을 다루어 왔는데, 여기에 새로운 심리적인 특성인 창의성을 추가하여 연구하였다. 본 연구의 실증 분석을 위하여 서울과 대구의 성공창업패키지 교육 실행기관 중 임의의 기관을 선정하여 예비창업자 200명을 대상으로 대응표본 T-검증과 ANCOVA를 실행하였다. 분석결과는 창업교육전과 창업교육 후를 비교하여 볼 때 성취욕구와 모호성의 수용, 창의성은 향상되어진 것으로 나타났다. 다만 통제 위치와 위험 감수 성향은 창업교육 전 후에 차이가 없는 것으로 나타났다. 연령, 학력 그리고 창업교육 횟수에 따라 창업교육 전후의 심리적 특성의 차이가 있는 가에 대한 검증에서는 유의한 차이가 없는 것으로 나타났다.

• 천문학회보
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• 제43권1호
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• pp.32.1-32.1
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• 2018

Searching for low surface brightness (LSB) dwarf galaxies in low density environments (isolated and group) can help us resolve the discrepancy between observation and theory known as the 'missing satellite' problem. They are also important to study the evolution of low mass galaxies in these environments. Although the number of dwarfs in such environments is rapidly increasing in many recent studies, it is still not easy to characterize their general properties. Motivated by this, we present preliminary results of our search for LSB dwarf galaxies around 60 nearby galaxies (D<50Mpc) using deep optical images. Imaging data from Maidanak Astronomical Observatory (MAO) in Uzbekistan as a part of Intensive Monitoring Survey of Nearby Galaxies (IMSNG; Im in prep.) and other archival data are used to find previously unknown LSB dwarf galaxies. Extended LSB sources (central surface brightness ${\mu}_0$ > $23mag/arcsec^2$) are first selected in the ${\mu}_0$ - magnitude plane (Rines & Geller 2008). The dwarf galaxy candidates are chosen by visual inspection. We discuss whether these candidates are actual satellite galaxies, by measuring the projected number densities in group environments and in the field. Also, their structural and photometric properties are compared with those of previously discovered dwarf galaxies in the literature.

• Asian Pacific Journal of Cancer Prevention
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• 제17권1호
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• pp.57-64
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• 2016

Background: Tobacco smoking is considered a risk factor for cervical cancer development due to the presence of tobacco based carcinogenic metabolites in cervical cells of female smokers. In this study, we investigated the role of the T3801C (MspI) polymorphism of CYP1A1, a gene encoding an enzyme necessary for the initiation of tobacco based carcinogen metabolism, on cervical cancer risk. The T to C substitution may alter CYP1A1 activities, potentially elevating cervical cancer risk. Since results of gene-disease association studies vary according to the study population, the multi-ethnic population of Malaysia provides an excellent representative cohort for identifying and comparing the cervical cancer risk among the 3 major ethnics in Southeast Asia in relation to CYP1A1 MspI polymorphism. Materials and Methods: A total of 195 Thin Prep Pap smear samples from HPV negative and cancer free females were randomly selected as controls while 106 formalin fixed paraffin embedded samples from females with invasive cervical cancer were randomly selected for the cases group. The polymorphisms were identified using restriction fragment length polymorphism (RFLP) PCR. Results: We found no significant associations between CYP1A1 MspI polymorphism and cervical cancer in the general Malaysian female population. However, upon ethnic stratification, the variant C/C genotype was significantly associated with a 4.66-fold increase in cervical cancer risk in Malay females (95% CI= 1.21-17.9; p=0.03). No significant association was observed in the Chinese and Indian females. Additionally, there were no significant associations in the dominant model and allele frequency model analysis in both the general and ethnically stratified female population of Malaysia. Conclusions: Our findings suggest that the C/C genotype of CYP1A1 MspI polymorphism is associated with the development of cervical carcinoma in the Malay females of Malaysia.

• Asian Pacific Journal of Cancer Prevention
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• 제17권7호
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• pp.3489-3494
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• 2016

Background: A major problem with cervical cancer screening in countries which have no organized national screening program for cervical cancer is sub-optimal participation. Implementation of self-sampling method may increase the coverage. Objective: We determined the agreement of cytological diagnoses made on samples collected by women themselves (self-sampling) versus samples collected by physicians (Physician sampling). Materials and Methods: We invited women volunteers to undergo two procedures; cervical self-sampling using the Evalyn brush and physician sampling using a Cervex brush. The women were shown a video presentation on how to take their own cervical samples before the procedure. The samples taken by physicians were taken as per routine testing (Gold Standard). All samples were subjected to Thin Prep monolayer smears. The diagnoses made were according to the Bethesda classification. The results from these two sampling methods were analysed and compared. Results: A total of 367 women were recruited into the study, ranging from 22 to 65 years age. There was a significant good agreement of the cytological diagnoses made on the samples from the two sampling methods with the Kappa value of 0.568 (p=0.040). Using the cytological smears taken by physicians as the gold standard, the sensitivity of self-sampling was 71.9% (95% CI:70.9-72.8), the specificity was 86.6% (95% CI:85.7-87.5), the positive predictive value was 74.2% (95% CI:73.3-75.1) and the negative predictive value was 85.1% (95% CI: 84.2-86.0). Self-sampling smears (22.9%) allowed detection of micro-organisms better than physicians samples (18.5%). Conclusions: This study shows that samples taken by women themselves (self-sampling) and physicians have good diagnostic agreement. Self-sampling could be the method of choice in countries in which the coverage of women attending clinics for screening for cervical cancer is poor.

• 한국식품영양학회지
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• 제26권3호
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• pp.547-552
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• 2013

황백 껍질은 황벽나무(Phellodendron amurense)의 건조된 수피로부터 얻어진다. 이 수피는 한국의 전통 한약제로서, 설사, 황달, 무릎과 발의 통증, 요도관 및 피부 감염증에 폭넓게 사용되어 왔다. 본 연구는 황벽나무의 메탄올 추출액으로부터 항균성 화합물 분리를 위해 CPC 방법으로 효과적으로 수행하였다. 두 용매의 CPC 최적조성은 n-butanol:acetic acid:water(4:1:5 v/v/v)이었다. 이동상의 유속은 1,000 rpm 회전력에서 상승법으로 분당 3 $m{\ell}$ 속도로 전개시켰다. CPC에서 분리된 분획분은 prep-HPLC로 정제하였다. 분리된 palmatine은 $^1H$, $^{13}C$-NMR, ESI-MS 데이터 분석으로 확인하였다.