• Bulletin of the Korean Chemical Society
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• v.21 no.8
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• pp.823-827
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• 2000

Gas-Phase reactions of methyl and ethyl nitrites with anionic nucleophiles of SH-, F- and OH- are investigated theoretically at the MP2/6-311+G* level. The SN2 processes are all highly exothermic and proceed with a typ-icaI double-weIl reaction coordinate profile. The elimination reactions of methyl nitrite with SH- and F- are double-well energy surface processes,with stabilizedproduct complexes of NO-...H2S and NO-...HF, pro-ceeding by an E1 cb-like E2 mechanism. The $\beta-elimination$ of ethyl nitrite is an E2 type process. The $\alpha-elimi-nation$ reactions of methyl and ethyl nitrites with OH- have triple-well energy profiles of Elcb pathway with an $\alpha-carbanion$ intermediate which is stabilized bythe vicinal $nc\alpha-{\sigma}*o-N$ charge transfer interactions. CompIex-ation ofmethyl carbanion with HF seems to provide a stable intermediate within a triple-well energy profile of El cb channel in the reaction of F- with methyl nitrite.

• The Journal of the Korean Society for Microbiology
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• v.34 no.6
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• pp.573-582
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• 1999

Cytokines are hormone-like proteins which mediate and regulate inflammatory and immune responses. The purpose of this study was to investigate the effect of lipopolysaccharide (LPS), Staphylococcus enterotoxin B (SEB), and Mycoplasma lysates on regulation of IL-6 and IL-8 production by human nasal fibroblasts. Primary cultured cells were incubated with LPS ($1.0\;{\mu}g/ml$) from E.coli, SEB ($1.0\;{\mu}g/ml$) from S.aureus, or Mycoplasma lysates (M.pneumoniae, Mp; M. fermentans, Mf; M. hominis, Mh, each $1.0\;{\mu}g/ml$). The culture supernatants were collected at 2, 6, and 24 hr and assessed for IL-6 and IL-8 production by enzyme-linked immunosorbent assay. The production of IL-6 in the culture supernatant was downregulated by LPS, SEB, or Mycoplasma lysates. But IL-6 was upregulated by mixed exposure with Mp+LPS (2 hr), Mp+LPS+SEB (24 hr), Mf+LPS (24 hr), Mf+LPS+SEB (2 hr), Mh+LPS (24 hr), Mh+SEB (24 hr), or Mh+LPS+SEB (24 hr). The production of IL-8 in the culture supernatant was similar to that of IL-6 by same stimulants. But IL-8 was upregulated by mixed exposure with Mf+LPS+SEB (2 hr), Mh+LPS (24 hr), Mh+ SEB (24 hr), or Mh+LPS+SEB (24 hr). These studies show that costimulation of LPS or SEB with Mycoplasma whole cell lysates upregulates the production of IL-6 and IL-8.

• The Journal of Advanced Prosthodontics
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• v.7 no.6
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• pp.454-459
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• 2015

PURPOSE. To determine whether the fracture strengths and failure types differed between metal and zirconia frameworks veneered with pressable or layering ceramics. MATERIALS AND METHODS. A phantom molar tooth was prepared and duplicated in 40 cobalt-chromium abutments. Twenty metal (IPS d.SIGN 15, Ivoclar, Vivadent, Schaan, Liechtenstein) and 20 zirconia (IPS e.max ZirCAD, Ivoclar) frameworks were fabricated on the abutments. Each framework group was randomly divided into 2 subgroups according to the veneering material: pressable and layering ceramics (n=10). Forty molar crowns were fabricated, cemented onto the corresponding abutments and then thermocycled ($5-55^{\circ}C$, 10,000 cycles). A load was applied in a universal testing machine until a fracture occurred on the crowns. In addition, failure types were examined using a stereomicroscope. Fracture load data were analyzed using one-way ANOVA and Tukey HSD post-hoc tests at a significance level of 0.05. RESULTS. The highest strength value was seen in metal-pressable (MP) group, whereas zirconia-pressable (ZP) group exhibited the lowest one. Moreover, group MP showed significantly higher fracture loads than group ZP (P=.015) and zirconia-layering (ZL) (P=.038) group. No significant difference in fracture strength was detected between groups MP and ML, and groups ZP and ZL (P>.05). Predominant fracture types were cohesive for metal groups and adhesive for zirconia groups. CONCLUSION. Fracture strength of a restoration with a metal or a zirconia framework was independent of the veneering techniques. However, the pressing technique over metal frameworks resisted significantly higher fracture loads than zirconia frameworks.

• Korean Journal of Pharmacognosy
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• v.16 no.3
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• pp.151-154
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• 1985

From the BuOH Fr. of the roots of Acanthopanax koreanum $N_{AKAI}$, we have isolated a lignan glucoside, mp $257{\sim}259^{\circ}$, $C_{34}H_{46}O_{18}$ and it was identified to be (-) syringaresinol diglucoside by spectral data and comparing with authentic samples.

• Archives of Pharmacal Research
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• v.6 no.2
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• pp.133-136
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• 1983

From ether-soluble neutral fraction of the whole plant of Peperomia pellucida (L) HBK (Piperaceae), 4, 7-dimethoxy-5-(2-propenyl)-1, 3-benzodioxole or apiol, in a liquid state, 2, 4, 5-trime-thoxy styrene, mp 138.deg. and three phytosterols, campesterol, stigmasterol and .betha.-sitosterol, were isolated and characterized by spectral data.

• Digital Contents
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• no.9 s.124
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• pp.48-51
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• 2003

전자책이란 도서로 간행됐거나 간행될 수 있는 저작물의 내용이 디지털 데이터를 이용해 전자 기록매체, 저장장치에 수록된 뒤, 유무선 정보통신망을 통해 컴퓨터나 휴대단말기로 그 내용을 읽고, 보고, 들을 수 있도록 한 디지털 도서를 총칭한다. 이렇게 볼때 로버트 기요사키가 만든 '부자 아빠, 가난한 아빠'를 한글 문서나 워드로 만들어 개인 PDA에서 읽는 것도 전자책의 형태일 수 있으며, 한국전자북이 판매하는 하이북 단말기에서 'YBM 시사영어사'의 토익을 보고 MP3로 들을 수 있어도 전자책이다. 이렇듯 큰 의미로는 저작물이 도서로 발간됐거나 가능성이 있는 저작물을 디지털 데이터로 변환된 모든 것을 전자책이라 할 수 있지만 본 지면에서는 국, 내외 상업화된 유로 전자책 사이트에서 제공되는 전자책에 활용되는 솔루션만을 대상으로 한다.

• Journal of Korean Library and Information Science Society
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• v.54 no.4
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• pp.281-306
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• 2023

This study analyzed the legal deposit, acquisition, and donation status from 2020 to 2022, along with the deposit status of e-publications with issued ISBNs. Through this analysis, the study derived improvement measures to strengthen compliance with legal deposit obligations for domestic e-publications. The key findings are as follows: The collection methods were acquisition (57.07%), legal deposit (41.74%), and donation (1.19%). The file formats varied, including e-books (pdf, epub), webtoons (jpg), and audiobooks (mp3). Most e-publications collected were published from 2012 to 2022, with some from 1960 to 2011. Webtoons dominated acquired materials, while legal deposits mainly comprised e-books. Analyzing the status of e-publications with issued ISBNs, e-books (96.2%) were most common, with the literature field receiving the highest number of ISBNs. Most ISBNs were issued during 2020 to 2022. Looking at the top 10 publishers, the low legal deposit rate indicates the need for improvement. To address this, proposed improvement measures include enhancing publishers' awareness of legal deposits, strengthening incentives and sanctions, encouraging voluntary participation through transparent disclosure of the legal deposit status, and improving the accuracy of data in the ISBN issuance and deposit system.

• Korean Journal of Poultry Science
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• v.39 no.4
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• pp.253-260
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• 2012

This study was undertaken to investigate the influence of multi-probiotics, fermented ginseng byproducts and fermented sulfone as an alternative to probiotics on performance, intestinal microflora and immunity of broiler. A five weeks trial was conducted with one day old Ross${\times}$Ross broilers (n=340), divided into five groups which further divided into 4 replicates with 17 birds in each replicate. Birds were assigned to 5 dietary treatments as control, antibiotic avilamycin (AB), multi-probiotics (MP), fermented sulfone (FS) and fermented ginseng byproducts (FGB). Growth parameters were recorded on weekly basis while rest of the parameters viz. blood and faeces were collected at the end of the experiment. Growth parameters were not affected statistically by dietary treatments. However, numerically, higher body weight, splenocytes proliferation and lower total cholesterol and LDL values were found in MP treatment (P>0.05). Salmonella spp. count ($P{\leq}0.001$) and E. coli (P<0.001) concentrations in the ileum were found lowest in AB treatment while FS group showed lowest level of yeast (P<0.10) and Lactobacillus spp. ($P{\leq}0.001$). Fecal ammonia and $CO_2$ emission was significantly decreased in FGB than other dietary treatments (P<0.05). It was concluded that multi-probiotics would be valuable feed additives to improve the growth performance, Lactobacillus proliferation and immunity of broiler chicks.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.2
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• pp.403-411
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• 2003

For evaluating the effect of Siegesbeckiae Herba (here after abbreviated as SBH) on rheumatoid arthritis, the experiment was carried out; Incidence of rheumatoid arthritis, IRA(indices of rheumatoid arthritis), immunophenotypes by flow cytometer and histopathological changes in MRL/MpJ-Ipr-Ipr Mice in vivo were studied. The results were obtained as follows: 1. Incidence of RA in MRL/Ipr mice was suppressed to 60% of control by SBH. 2. IRA was significantly reduced for IgG3 and IgM at 20 weeks of age and for IgG2b at 12 and 20 weeks of age in mice by SBH compared with control. 3. Immunophenotypes such as CD4/sup +//CD25/sup +/, CD8/sup +//CD3e/sup +/, CD69/sup +//B220/sup +/, NK/sup +//CD3e/sup +/ were significantly increased by SBH compared with control. 4. In histopathological analysis, SBH suppressed the progression of PMN(polymorphonuciear leukocyte), leukocyte and fibroblast infiltration, and subsynovial soft tissue edema frequently showing in the early stage of the arthritis, and also effectively reduced the degeneration of cartilages and degenerative bone symptoms. These results suggest Siegesbeckiae Herba can be effectively applied to the treatment of rheumatoid arthritis and it is still necessary to isolate effective compound from Siegesbeckiae Herba in the near future.

• International Commerce and Information Review
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• v.7 no.3
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• pp.195-212
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• 2005

International trade has been changed from traditional trade to e-trade due to the fast expanding of information technology like e-marketplace, EDI (Electronic data interchange) using Internet since mid of 1990's. e-Trade, as a new trade method, could handle every trade procedure such as market research, contract, customs clearance, logistics and payment using IT like internet without restriction of time and space. The evolution of transaction-based business model is upon us. The business models of many e-Marketplace in their early stages have typically been based on transaction fees. Many e-Marketplaces have even called out transaction revenues as a core element of their business plans. The transaction business represents the most simple of business models, but it does not provide a long-term sustain able advantage. For buyer's convenience, wide selection and test price hold appeal. For suppliers, the extended global market reach and direct access to customers and consortiums of customers is powerful. To maximize leverage of these new e-marketplace, you must from both a buyer perspective as well as a supplier perspective. Also required is a strategy that takes in account all of the various e-Marketplace transaction standards and one that allows the easy accomodation to new e-marketplace as the market change. These new e-marketplace will need to be factored into the sales channel strategies. To be successful, integration with these e-marketplaces should occur at a complete business process level. This study would suggest on the role of buyers and sellers for e-trade which could maximize effect of e-trade in order to cope with rapid changing IT environment and global trade environment. Therefore, this study suggests top priority tasks for implementing on the specialization strategy of e-trade process.