• 대한화학회지
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• 제43권4호
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• pp.447-455
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• 1999

Allyl (5R)-dibromopenicillanate(6)의 2,3-O-isopropylidene-D-glyceraldehyde와의 축합, $Zn-NH_4OAc$에 의한 환원 및 Mitsunobu 제거반응의 일련의 과정을 거처서 allyl (5R)-(Z) 및 (5R)-(E)-6-[(2S)-2,3-isopropylidenedioxypropylidene]penicillanate(10a 및 10b)를 합성하였다. 화합물10a의 이소프로필리덴 및 알릴 보호기를 제거하여 potassium (5R)-(Z)-6-[(2S)-2,3-dihydroxypropylidene]penicilla-nate(4)를 얻었다. 그러나 화합물 10b의 이소프로필리덴 보호기를 제거한 결과 ${\alpha},\;{\beta}$-unsaturated-lactone(12)이 얻어짐을 확인하였다. Allyl(5R)-6,6-dibromopenicillanate(6)의 (2S)-2-(t-butyldimethyl-silyloxy)propanal(15)과의 축합, $Zn-NH_4OAc$에 의한 환원 및 Mitsunobu 제거반응 또는 메실화-제거반응의 일련의 과정을 거처서 allyl (5R)-(Z)- 및 (5R)-(E)-6-[(2S)-2-(t-butyldimethylsilyloxy)propylidene]-penicillanate(18a 및 18b)를 합성하였다. 화합물 18a 및 18b의 t-부틸디메틸실릴 및 알릴 보호기를 제거하여 potassium (5R)-(Z)- 및 (5R)-(E)-6-[(2S)-2-hydroxypropylidene]penillanate(5a 및 5b)를 얻었다.

• Parasites, Hosts and Diseases
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• 제37권3호
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• pp.181-188
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• 1999

We investigated the value of mitochondrial small subunit rRNA gene (mt SSU rDNA) PCR-RFLP as a taxonomic tool for Acanthamoeba isolates with close inter-relationships. Twenty-five isolates representing 20 species were included in the analysis. As in nuclear 18s rDNA analysis, two type strains (A. astronyxis and A. tubiashi) of morphological group 1 diverged earliest from the other strains, but the divergence between them was less than in 18s riboprinting. Acanthamoeba griffini of morhological group 2 branched between pathogenic (A. culbertsoni A-1 and A. healyi OC-3A) and nonpathogenic (A.palestinensis Reich, A. pustulosa GE-3a, A. royreba Oak Ridge, and A lenticulata PD2S) strains of morphological group 3. Among the remaining isolates of morphological group 2, the Chang strain had the identical mitochondrial riboprints as the type strain of A. hatchetti. AA2 and AA1, the type strains of A. divionensis and A. paradivionensis, respectively, had the identical riboprints as A. quina Vil3 and A. castellanii Ma. Although the branching orders of A. castellanii Neff, A. polyphaga P23, A. triangularis SH621, and A. lugdunensis L3a were different from those in 18S riboprinting analysis, the results obtained from this study generally coincided well with those from 18S riboprinting. Mitochondrial riboprinting may have an advantage over nuclear 18S rDNA riboprinting beacuse the mt SSU rDNAs do not seem to have introns that are found in the 18S genes of Acanthamoeba and that distort phylogenetic analyses.

• Bulletin of the Korean Chemical Society
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• 제27권10호
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• pp.1577-1580
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• 2006

The article reports the synthesis and enantiomeric recognition of a new chiral azophenolic pyridino-18-crown-6 ether, (S,S)-6, possessing diphenyl groups as chiral barriers. The association constants for the enantiomeric recognition of chiral primary amines (7-12) using chiral azophenolic pyridino-18-crown-6 ether, (S,S)-6, were determined by UV-visible titration method in acetonitrile at $25{^{\circ}C}$.

• Molecules and Cells
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• 제19권2호
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• pp.283-288
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• 2005

Complete 18S rDNA sequences were determined for 10 vetigastropods in order to investigate the phylogeny of Vetigastropoda, which is controversial. These sequences were analyzed together with published sequences for nine other vetigastropods and two nerites. With the two nerites as outgroups, the phylogeny was inferred by three analytical methods, neighbor-joining, maximum likelihood, and maximum parsimony. The 18S rDNA sequence data support the monophyly of four vetigastropod superfamilies, the Pleurotomarioidea, the Fissurelloidea, the Haliotoidea, and the Trochoidea. The present results yield the new branching order: (Pleurotomarioidea (Fissurelloidea ((Scissurelloidea, Lepetodriloidea) (Haliotoidea, Trochoidea)))) within the vetigastropod clade.

• 대한안전경영과학회지
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• 제18권1호
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• pp.167-177
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• 2016

The CEO leadership and employee's concerning and participation to quality management innovation activity is critical factor for improving the business performance. This empirical study is aims to find that whether the quality management activity is significant or not in the automotive parts suppliers. To perform this research, we distributed 250 sheets totally, and withdraw 194 sheets. We analysed 169 sheets that we could use for this research using SPSS 18.0 and AMOS 18.0. We had the results that CEO leadership is significantly positive effects on the employees's participation to quality management. And the result of process improvement have positively effective and significant effects on the product improvement result and business performance of firms.

• Animal cells and systems
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• 제4권3호
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• pp.257-261
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• 2000

To elucidate phylogenetic relationships among poecilostome families 18S rDNA sequence data were generated for seven poecilostome and one cyclopoid copopods by PCR cloning and sequencing techmiques. Phylogenetic trees were constructed by maximum parsimony, neighbor joining, and maximum likelihood methods using cyclopoid sequence as an outgroup. The results from three different analyses showed that the seven poecilostome families were eiridel into two groups: Clausidiidae-Myicolidae-Synaptiphillidae-bomolochidae and Lichomologidae-Chondracanthidae-Ergasilidae. The molecular phylogenies were consistent with those from the morphological characters. Therefore, these analyses porvide further evidence for the utility of 18S rDNA sequences in addressing phylogenetic relationships among poecilostome families.

• Animal Systematics, Evolution and Diversity
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• 제38권3호
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• pp.144-147
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• 2022

The polychaete Scolelepis (Scolelepis) sagittaria was originally described from Japanese waters and subsequently reported from Korean waters. In this study, we determined for the first time the mitochondrial cytochrome c oxidase subunit I (COI), 16S ribosomal DNA (16S rDNA), and nuclear 18S ribosomal DNA (18S rDNA) sequences of Korean specimens of S. (S.) sagittaria. We also assessed intraspecific variation in the shape of the prostomium of this species based on an examination of 247 individuals. All materials were collected from intertidal sandy beaches of the Korea Strait. The molecular data and morphological observations reported herein will contribute to gaining a better understanding of the taxonomic relationships among members of the genus Scolelepis.

• 임상간호연구
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• 제21권2호
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• pp.188-195
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• 2015

Purpose: The purpose of this study was to evaluate the appropriateness of the replacement time intervals of 18 gauge peripheral intravenous catheters (PICs) by investigating the development of phlebitis. Methods: The subjects were 200 hospitalized patients over 18 yrs old aged who have 18 gauge PICs placed for surgery. After the insertion of PICs, the researcher monitored the insertion site daily for 96 hours for any signs of phlebitis. Results: Phlebitis developed in 25.7% of patients. Patients who developed phlebitis were significantly older and were receiving fluids with faster infusion rate. However, patients with and without phlebitis were not different by gender, insertion site, fluid osmolality, or pH of drugs administered. The incidence rate of phlebitis was higher than 10%(12.9%) starting 24~48 hours after the insertion of 18 gauge PICs. Conclusion: It is recommended to replace 18 gauge PICs within 24~48 hours after insertion. Close monitoring of the PICs insertion site for the signs of phlebitis is recommended.

• Bulletin of the Korean Chemical Society
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• 제29권10호
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• pp.1973-1976
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• 2008

Electronic photodepletion spectrum of dibenzo-18-crown-6 with a potassium ion ($K^+$-DB18C6) was obtained in the gas phase using electrospray ionization and quadrupole ion-trap reflectron time-of-flight mass spectrometry. The spectrum exhibited rather a broad absorption band at 36350 $cm^{-1}$, which was tentatively assigned as the origin of the S1 band. The photodepletion spectrum of $Cs^+$-DB18C6 was also obtained to elaborate the effects of metal cations on electronic and geometric structures of metal cation-DB18C6 complexes. We found that the S1 band of $Cs^+$-DB18C6 was red-shifted by 180 $cm^{-1}$ from that of $K^+$-DB18C6. With the results of quantum theoretical calculations using the density functional theory, we suggested that the red-shift arose mainly from weaker binding of $Cs^+$ to DB18C6 than that of K+, which resulted from a larger size of $Cs^+$ than that of the cavity in DB18C6.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권2호
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• pp.154-159
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• 2006

Interleukin-18 (IL-18), otherwise known as interferon-gamma-inducing factor (IGIF), is one of several well characterized and important cytokines that contribute to host defenses. The complementary DNA (cDNA) of mature human interleukin-18 gene (hIL-18) was fused with the signal peptide of the rice amylase 1A gene (Ramy1A) and introduced into the plant expression vector under the control of a duplicated CaMV 35S promoter. The recombinant plasmid was transformed into tobacco (Nicotiana tabacum L. cv Havana) using the Agrobacterium-mediated transformation method. The integration of the hlL-18 gene into the genome of transgenic tobacco plants was confirmed by polymerase chain reaction (PCR) amplification and its expression was observed in the suspension cells that were derived from the transgenic plant callus by using Northern blot analysis. The hlL-18 protein was detected in the extracts of the transgenic callus and in the medium of the transgenic tobacco suspension culture by using immunoblot analysis. Based upon enzyme-linked immunosorbant assay (ELISA) results, the expression level of the hlL-18 protein approximated $166{\mu}g/L$ in the suspension culture medium. Bioassay results from the induction of $interferon-{\gamma}$ from a KG-1 cell line indicated that the hlL-18 secreted into the suspension culture medium was bioactive.