• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 1994년도 Proceedings of International Symposium on BIOLOGICAL CONTROL OF PLANT DISEASES Korean Society of Plant Pathology
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• pp.75-85
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• 1994

Biocontrol is playing a more and more important role in plant disease management. Evidences show that there are optimum prospects for people to apply biocontrol approach to control plant disease or to study the mechanism of antagonism.“The study of Antagonistic Protein of Bacillus spp.to Xanthomonas oryzae pv. oryzae”has been worked in our laboratory since 1986. One hundred and thirty antagonistics bacteria were screened out, most of them belonged to Bacillus spp., and showed very strong inhibitive effect to various plant pathogens. Nine antagonistic proteins (peptides) were purified (P11-I, P11-II, B8, B826-I, B826-II, A30-I, A30-II, G35). Two antagonistic protein related DNA fragments (B826-I, A30-II) were cloned and sequenced. B826-I DNA fragment composed by 905 bp, and it contained two ORF encoding 95, and 54 amino acids, respectively. By using Rifr and Kamr as the selective markers, we found the bacteria could colonize on rice leaf for at least 40 days. In greenhouse the antagonistic bacteria showed certain degree of control efficiency.

• Tuberculosis and Respiratory Diseases
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• 제55권5호
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• pp.488-498
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• 2003

연구배경 : 세포에 방사선을 조사하면 세포사멸과 함께 AP-l, NF-${\kappa}B$와 같은 여러 전사인자가 활성화 되는 것으로 알려져 있다. 이중 염증과 면역반응의 중요한 전사인자인 NF-${\kappa}B$는 항아포프토시스의 기능이 있으며 NF-${\kappa}B$ 활성화를 차단함으로써 TNF-${\alpha}$나 daunorubicine 등에 의 한 항암효과를 상승시킬 수 있음이 밝혀져 있다. NF-${\kappa}B$의 항아포프토시스 기전은 NF-${\kappa}B$ 의존성 단백질인 cIAPI, 2의 전사발현 유도에 의한 것으로 cIAPl, 2는 caspase 3, 7, pro-caspase-9의 활성을 차단함으로써 아포프토시스를 억제하는 것으로 알려져 있다. 이에 저자들은 방사선 유도성 세포사멸에 비교적 내성을 보이는 A549 세포주에서 방사선에 의한 NF-${\kappa}B$ 활성화와 그에 따른 cIAP 발현유도를 조사하고 NF-${\kappa}B$ 활성화를 차단하여 방사선 유도성 세포사멸의 감작효과를 확인하기 위하여 본 연구를 시행하였다. 방 법 : 세포주는 A549 폐암세포주를 이용하였고, 방사선 조사는 Varian사의 Clinac 1800C 선형가속기를 이용하였으며 조사량은 10GY를 사용하였다. 세포독성 검사는 MTT Assay를 이용하였고, NF-${\kappa}B$ 활성화 검사는 luciferase reporter gene assay, electromobility shift assay, $I{\kappa}B-{\alpha}$ degradation에 대한 westem blot을 이용하였다. NF-${\kappa}B$활성을 차단하기 위하여 proteosome inhibitor인 MGI32와 $I{\kappa}B{\alpha}$-superrepressor plasmid를 transfection한 안정적 세포주 A549-$I{\kappa}B{\alpha}$-superrepressor를 이용하였다. cIAP의 발현은 RT-PCR을 이용하였고, cIAP2 promoter 활성은 NF-${\kappa}B$ site를 포함한 cIAP2 유전자 5' f1anking region(1.4kb)을 pGL2-Basic luciferase vector에 cloning 한 construct를 사용하여 transfection 후 luciferase assay를 시행하였다. 결 과 : A549 cell에서 10Gy 방사선 조사에 의한 세포독성은 24hr, 48hr에 각각 $10.82{\pm}.3%$, $17.7{\pm}6.4%$로 비교적 내성이 있음을 확인하였다. 방사선에 의한 NF-${\kappa}B$의 활성은 $I{\kappa}B-{\alpha}$ 분해에 대한 western blot과 EMSA로 확인하였으며 luciferase assay에서도 약 1.6 배 정도의 NF-${\kappa}B$ 활성화가 있었다. NF-${\kappa}B$활성을 차단하기 위해 사용한 MG132는 방사선 유도성 세포사멸에 영향을 주지 않았으며 A549-$I{\kappa}B{\alpha}$-superrepressor 세포주에서도 세포사멸의 감작효과는 없었다. 또한 RT-PCR 결과 방사선에 의한 cIAP1,2 mRNA 발현유도는 관찰되지 않았고 cIAP2 promoter luciferase assay에서도 cIAP2 전사활성 유도는 없었다. 결 론 : A549 폐암세포주에서 방사선에 의해 NF-${\kappa}B$의 활성화는 확인하였으나 활성화 정도가 미약하였고 NF-${\kappa}B$ 의존성 항아포프토시스 유전자인 cIAP가 방사선에 의해 발현유도 되지 않았으며, NF-${\kappa}B$ 활성을 차단함에도 세포독성에 감작효과가 없었으므로 A549 폐암세포주에서 방사선 유도성 세포사멸에 내성을 보이는 기전에는 NF-${\kappa}B$의 역할이 미미하리라고 사료된다.

• 대한수학회보
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• 제58권5호
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• pp.1069-1078
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• 2021

Let R be a commutative ring with identity. A proper ideal I of R is called 1-absorbing primary ([4]) if for all nonunit a, b, c ∈ R such that abc ∈ I, then either ab ∈ I or c ∈ ${\sqrt{1}}$. The concept of 1-absorbing primary ideals in a polynomial ring, in a PID and in idealization of a module is studied. Moreover, we introduce weakly 1-absorbing primary ideals which are generalization of weakly prime ideals and 1-absorbing primary ideals. A proper ideal I of R is called weakly 1-absorbing primary if for all nonunit a, b, c ∈ R such that 0 ≠ abc ∈ I, then either ab ∈ I or c ∈ ${\sqrt{1}}$. Some properties of weakly 1-absorbing primary ideals are investigated. For instance, weakly 1-absorbing primary ideals in decomposable rings are characterized. Among other things, it is proved that if I is a weakly 1-absorbing primary ideal of a ring R and 0 ≠ I₁I₂I₃ ⊆ I for some ideals I₁, I₂, I₃ of R such that I is free triple-zero with respect to I₁I₂I₃, then I₁I₂ ⊆ I or I₃ ⊆ I.

• 말소리와 음성과학
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• 제2권3호
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• pp.23-27
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• 2010

The purpose of this study was to find how English vowels /a, e, i, o, u/ affect the production of English labials /p, b, f, v/ by Korean learners of English. Sixty syllables were composed by five vowels and four labials in the syllable types CV, VC, and VCV. The nonsense syllables were produced three times by nine subjects. The major results show that (1) in inter-vocalic position, the subjects had higher scores in producing /v/ composed with /a, e, o/ and /u/, while subjects had lower scores in producing /p/ with /i/ and /o/, (2) in post-vocalic position, the subjects had higher scores in producing /v/ and /f/ with /a, e/, and /o/, while subjects had lower scores in producing /b/ with /e/ and /i/, and (3) in pre-vocalic position, the subjects had higher scores in producing /v/ with /e, o, u/ and /f/ with /u/, while subjects had lower scores in producing /b/ with /e/, /i/ and /u/. The results suggest that on the whole, Korean learners of English have much difficulty in producing /p/ with /i/ in inter-vocalic condition and /b/ with /i, /e/ in pre-vocalic position.

• Biomolecules & Therapeutics
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• 제13권3호
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• pp.138-142
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• 2005

Adenosine and GABA are known to be major inhitory neurotransmitters in the central nervous system and its receptors mediate various neurophamacological effects including cardiovascular modulatory effects. Inhibitory cardiovascular effects induced by intrathecal (i.t.) administration of adenosine $A_1$ receptor agonist and its modulation by cyclic AMP was suggested by our previous report. In this experiment, we examined the modulation of cardiovascular effects of adenosine $A_1$ receptor and adenosine $A_2$ receptor by $GABA_B$ receptors antagonist in the spinal cord. I.t. administration of 10 nmol of $N^6$-cyclohexyladenosine (CHA, an adenosine $A_1$ receptor agonist), I.t. administration of 2 nmol of 5'-(N-cyclopropyl)-carboxamidoadenosine (CPCA, an adenosine $A_2$ receptor agonist), pretreatment with 5-aminovaleric acid (a $GABA_B$ receptor antagonist, 50 nmol, i.t.) prior to administration of CHA and pretreatment with 5-aminovaleric acid (a $GABA_B$ receptor antagonist, 50 nmol, i.t.) prior to administration of CPCA were performed in anesthetized, artificially ventilated Sprague-Dawley rats. I.t. administration of 50 nmol of 5-aminovaleric acid significantly attenuated the inhibitory cardiovascular effects of CHA but did not attenuated the inhibitory cardiovascular effects of CPCA. It is suggested that cardiovascular responses of adenosine $A_1$ receptor is modulated by $GABA_B$ receptor and adenosine $A_2$ receptor is not modulated by $GABA_B$ receptor in the spinal cord.

• 대한수학회보
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• 제30권2호
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• pp.213-221
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• 1993

In this paper, we will show that the multiplicative group G in a finite ring R with identity 1 has a (B, N)-pair satisfying the following conditions; (1) G=BNB where B and N are subgroups of G. (2) B.cap.N is a normal subgroup of N and W = N/(B.cap.N), is generated by a set S = { $s_{1}$, $s_{2}$, .., $s_{k}$} where $s_{i}$.mem.N/(B.cap.N), $s_{i}$$^{2}$.iden.1 and $s_{i}$.neq.1. (3) For any s.mem.S and w.mem.W, we have sBw.contnd.BwB.cup.BswB. (4) We have sBs not .subeq. B for any s.mem.S. When G, B, N and S satisfy the above conditions, we say that the quadruple (G, B, N, S) is a Tits system. The group W is called the Weyl gorup of the Tits system.ystem.m.

• 대한수학회보
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• 제35권4호
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• pp.615-624
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• 1998

We consider a generalization of [1. theorem 2.5]. We give a description of the element of $_{\mathcal I}^l$(resp. $_{\mathcal I} ^r$), where A and B are left (resp. right)${\mathcal I}$-ideals of an IS-algebra X. For a nonempty left (resp. right) stable, we obtain a condition for $_{\mathcal I}^l$(resp. $_{\mathcal I}^l$) to be closed. We give a characterization of a closed $\mathcal I$-ideal in an IS-algebra, and show that in a finite IS-algebra, every $\mathcal I$-ideal is closed.

• Journal of Gastric Cancer
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• 제7권1호
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• pp.16-22
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• 2007

목적: 하부 위암의 절제술 후 각각의 재건술에 따른 환자의 위배출시간과 영양상태, 덤핑 증후군의 발생정도를 비교하여 환자의 증상과 삶의 질을 개선하는 방법을 찾고자 하였다. 대상 및 방법: 1999년 6월부터 2002년 7월까지 원위부 위암으로 절제술을 시행한 환자 중 2003년 1월 한 달간 외래에서 술 후 6개월 이상 경과한 환자 122명을 대상으로 하였다. 위십이지장문합술을 받은 환자(이하 B-I군)는 51명, 위공장문합술을 받은 환자(이하 B-II군)는 71명이었다. 위배출검사는 동위원소 검사법을 이용하여 T1/2값을 얻어 비교하였고, 식사 횟수와 양, 체중감소 정도를 비교하였다. 수술 후 복부증상을 비교하였으며, 덤핑증후군은 Sigstad score를 측정하여 비교하였다. 결과: 수술 후 6개월의 T1/2값은 B-I군에서 지연되어 있었다($159.4{\pm}31.0min$). 12개월 후에는 B-I군의 위배출시간이 빨라져 B-I군과 B-II군 사이의 위배출 시간의 차이가 없어졌다. 식사 횟수는 각 군 간의 차이가 없었고 일회식사량은 수술 전과 비교해 보았을 때 6개월째는 각군간의 차이가 없었으나 12개월에는 B-I군이 B-II군에 비해 식사량이 많은 것으로 나타났다(P=0.038). 수술 후 체중은 B-I군이 B-II군에 비해 체중감소가 의미있게 적은 것으로 나타났다(P=0.023). Sigstad dumping score는 B-I군에서 6개월째에는 7.6점, 12개월째에는 3.4점으로 시간이 경과함에 따라 덤핑 증후군의 빈도가 감소하나 B-II군에서는 시간의 경과해도 덤핑 증후군의 빈도에는 유의한 차이가 없었다. 결론: 원위부 위암환자에서 근치적 수술이 가능한 한도에서는 Billroth I 술식이 체중감소가 적고, 복부 증상도 적게 나타났으며 덤핑증후군의 빈도도 낮아 환자의 삶의 질을 개선하는데 B-II 술식보다 유용한 술식으로 생각된다.

• ALGAE
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• 제17권1호
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• pp.53-58
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• 2002

The transition of plant life from aquatic algae to land to land plants was one of the major events in the history of life. However, in hypothesizing the exact evolutionary path of the transition, limited shared phenotypic characters in aquatic algae and land plants (embryophytes) have been a major hinderance. Chloroplast genomes contain characters useful in tracing evolutionary histories. Embryophyte chloroplast genomes are distinguished from algal cpDNAs by having over 20 group Ⅱ introns, some of which were gained during the transition from algae to embryophytes (Manhart and Palmer 1990; Lew and Manhart 1993;Lee and Manhart 2002). Here we examine a gene cluster that, in land plants, contains psbB, psbT, psbH, petB and petD with introns found in petB and petD (petB.i and petD.i). In addition the presence/absence of introns in trnA and trnI (trnA.i and trnI.i) were determined in all five major lineages of charophytes. We found that the psbB gene cluster occurs in most surveyed charophytes and embryophytes except Spirogyra (Zygnematales) which lacks it due to intra-genomic rearrangement. All four introns are absent in Chlorokybus but present in some or all of the other four charophyte lineages (Klebsormidiales, Zygnematales, Coleochaetales, and Charales). In addition, Chlorokybus is distinguished from other charophytes and embryophytes by having an unusually long spacer (over 2 kb) between psbH-petB. The results indicate that Chlorokybus diverged before the intron gains but after psbB gene cluster formation, placing the other charophyte lineages closer to embryophytes.

• The Korean Journal of Physiology and Pharmacology
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• 제5권6호
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• pp.521-527
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• 2001

Diclofenac, a phenylacetic acid derivative, is a widely used non-steroidal anti-inflammatory drug (NSAID) to provide effective relief of inflammation and pain. Nitric oxide (NO) synthesized by inducible nitric oxide synthase (iNOS) has been implicated as a mediator of inflammation. We examined the inhibitory effects of diclofenac on the induction of iNOS in RAW 264.7 macrophages which were activated with lipopolysaccharide (LPS) plus interferon-gamma $(IFN-{\gamma}).$ Treatment of RAW 264.7 cells with diclofenac and other NSAIDs (aspirin and indomethacin) significantly inhibited NO production and iNOS protein expression induced by LPS plus $IFN-{\gamma}.$ Also, diclofenac but not aspirin and indomethacin, inhibited iNOS mRNA expression and nuclear factor-kappa B $(NF-{\kappa}B)$ binding activity concentration-dependently. Furthermore, transfection of RAW 264.7 cells with iNOS promoter linked to a CAT reporter gene revealed that only diclofenac inhibited the iNOS promoter activity induced by LPS plus $IFN-{\gamma}$ through the $NF-{\kappa}B$ sites of iNOS promoter. Taken together, these suggest that diclofenac may exert its anti-inflammatory effect by inhibiting iNOS gene expression at the transcriptional level through suppression of $NF-{\kappa}B$ activation.