• 제목/요약/키워드: I-FORM

검색결과 3,862건 처리시간 0.035초

화학적수식에 의한 Bacillus subtilis ED 213 Cytidine Deaminase의 활성부위에 관한 연구 (A study on the Active Site of Cytidine Deaminase from Bacillus subtilis ED 213 by Chemical Modification)

  • 박정문;박상원;서태수;김정;유대식
    • 미생물학회지
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    • 제35권2호
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    • pp.133-138
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    • 1999
  • Bacillus subtilis ED 213의 cytidine deaminase 의 활성부위에 존재하는 필수 아미노산잔기를 화학수식 방법으로 측정하였다. 본 효소는 1mM o-phenanthroline 에 의하여 효소활성이 43% 저해되어 효소활성 발현에 Fe\sup 2+\가 요구된다고 추정되며, 1mM ethylenediaminetetraacetic acid 에 의해서는 효소활성이 오히려 28% 정도 촉진되었다. 본 효소는 1mM N-bromosuccinimide, 1mM chloramine-T 와 1mM $\rho$-chloromercuribenzoic acid에 의하여 100% 저해되었으며, 그의 저해 양상은 경쟁적 저해 양상을 나타내었다. 본 효소의 효소활성은 1mM pyridoxal-5-phosphate 에 의항 36% 저해되었으며, 1mM 1ethyl-3-carbodiamide 와 1mM glycine methylester에 의해 저해된 효소활성이 5mM cysteine에 의해 완전히 회복되었다. 이상의 결과로부터 Bacillus subtilis ED 213 cytidine deaminase의 활성부위에는 tyrosine, methionine, cysteine 과 serine 잔기가 관여할 뿐만 아니라 lysine 과 glycine 도 효소활성에 관여하는 것으로 추정된다.

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A Novel Complement Fixation Pathway Initiated by SIGN-R1 Interacting with C1q in Innate Immunity

  • Kang, Young-Sun
    • 한국미생물학회:학술대회논문집
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    • 한국미생물학회 2008년도 International Meeting of the Microbiological Society of Korea
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    • pp.23-25
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    • 2008
  • Serum complement proteins comprise an important system that is responsible for several innate and adaptive immune defence mechanisms. There were three well described pathways known to lead to the generation of a C3 convertase, which catalyses the proteolysis of complement component C3, and leads to the formation of C3 opsonins (C3b, iC3b and C3d) that fix to bacteria. A pivotal step in the complement pathway is the assembly of a C3 convertase, which digests the C3 complement component to form microbial-binding C3 fragments recognized by leukocytes. The spleen clears microorganisms from the blood. Individuals lacking this organ are more susceptible to Streptococcus pneumoniae. Innate resistance to S. pneumoniae has previously been shown to involve complement components C3 and C4, however this resistance has only a partial requirement for mediators of these three pathways, such as immunoglobulin, factor B and mannose-binding lectin. Therefore it was likely that spleen and complement system provide resistance against blood-borne S. pneumoniae infection through unknown mechanism. To better understand the mechanisms involved, we studied Specific intracellular adhesion molecule-grabbing nonintegrin (SIGN)-R1. SIGN-R1, is a C-type lectin that is expressed at high levels by spleen marginal-zone macrophages and lymph-node macrophages. SIGN-R1 has previously been shown to be the main receptor for bacterial dextrans, as well as for the capsular pneumococcal polysaccharide (CPS) of S. pneumoniae. We examined the specific role of this receptor in the activation of complement. Using a monoclonal antibody that selectively downregulates SIGN-R1 expression in vivo, we show that in response to S. pneumoniae or CPS, SIGN-R1 mediates the immediate proteolysis of C3 and fixation of C3 opsonins to S. pneumoniae or to marginal-zone macrophages that had taken up CPS. These data indicate that SIGN-R1 is largely responsible for the rapid C3 convertase formation induced by S. pneumoniae in the spleen of mice. Also, we found that SIGN-R1 directly binds C1q and that C3 fixation by SIGN-R1 requires C1q and C4 but not factor B or immunoglobulin. Traditionally C3 convertase can be formed by the classical C1q- and immunoglobulin-dependent pathway, the alternative factor-B-dependent pathway and the soluble mannose-binding lectin pathway. Furthermore Conditional SIGN-R1 knockout mice developed deficits in C3 catabolism when given S. pneumoniae or its capsular polysaccharide intravenously. There were marked reductions in proteolysis of serum C3, deposition of C3 on organisms within SIGN-$R1^+$ spleen macrophages, and formation of C3 ligands. The transmembrane lectin SIGN-R1 therefore contributes to innate resistance by an unusual C3 activation pathway. We propose that in the SIGN-R1 mediated complement activation pathway, after binding to polysaccharide, SIGN-R1 captures C1q. SIGN-R1 can then, in association with several other complement proteins including C4, lead to the formation of a C3 convertase and fixation of C3. Therefore, this new pathway for C3 fixation by SIGN-R1, which is unusual as it is a classical C1q-dependent pathway that does not require immuno globulin, contributes to innate immune resistance to certain encapsulated microorganisms.

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에너지 균형법에 의한 한우 수소의 유지 대사에너지 요구량 (Metabolizable Energy Requirement of Growing Hanwoo Bulls for Maintenance by Energy Equilibrium Metho)

  • 이상철;탁태영;김경훈;윤상기
    • Journal of Animal Science and Technology
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    • 제45권1호
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    • pp.123-130
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    • 2003
  • 수소 육성과 비육단계에서 필요로 하는 유지에너지 요구량을 구하기 위해 체중 100kg에서 400kg까지 100kg 증체 간격(100, 200, 300, 400 kg)으로 각 9두를 이용한 3처리(에너지 급여수준) 3반복의 에너지 균형 시험을 수행하였다. 에너지 급여수준은 대사에너지(Metabolizable energy; ME)로 1) 유지에너지 수준(Maintenance, 1.0M), 2) 유지에너지의 1.5배(1.5M), 3) 유지에너지의 2배(2.0M)을 섭취 할 수 있도록 1일 사료급여량을 정하였고, 조사료와 농후사료의 비율은 40:60을 유지하였다. 이와 같은 시험 설계를 기초로 각 체중별로 국내에서 주로 이용되는 볏짚(실험 I), 목건초(실험 II), 옥수수 사일리지(실험 III)의 조사료가 다른 조건에서의 유지에너지 요구량을 구하였다. 체중별 MEm은 체중 100kg시 99.80 kcal/ MBS로 가장 높았던 반면 체중 200kg시 가장낮아 94.48 kcal/$W^{0.75}$였고, Kg의 경우 0.36-0.57의 범위에 있었다. 체중별 성적을 종합 분석한 결과, 유지를 위한 대사에너지(MEm)는 95.80kcal, 증체를 위한 대사에너지 이용효율(Kg)은 0.44로 평가되어졌다.

이유자돈의 사료 첨가제로서 Copper Chelates(메치오닌, 키토산, 효모)의 효과 (Effect of Copper Chelates(Methionine-Cu, Chitosan-Cu and Yeast-Cu) as the Supplements to Weaning Pig Diet)

  • 김병한;임희석;남궁환;백인기
    • Journal of Animal Science and Technology
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    • 제45권1호
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    • pp.49-56
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    • 2003
  • 본 시험은 이유자돈사료에 Cu-chelates를 첨사시 자돈의 생산성과 혈액지질 및 IgG 수준에 미치는 영향을 측정하기 위하여 실시하였다. 4주령 된 이유자돈 48마리(암 수 각 24마리)를 4처리 4반복으로 반복 당 3마리씩 암수 구별하여 실시하였다. 본 시험에서 사용된 대조구 사료에는 137ppm의 구리가 함유되어 있으며 각 처리구는 대조구사료에 methionine-Cu chelate, chitosan-Cu chelate와 yeast-Cu chelate를 Cu 100ppm 수준에서 각각 첨가하였다. 5주간의 사양기간 동안 증체량은 개체 단위로, 사료섭취량은 pen 단위로 매주 측정을 하였다. 일당 증체량, 사료 섭취량, 사료효율 그리고, 영양소 이용률은 모두 처리간에 유의차를 보이지 않았다. 혈청 내 triglyceride 함량은 chito- san-Cu 처리가 methionine-Cu나 yeast-Cu 처리보다 유의하게 낮았으나 대조구와는 유의한 차이를 보이지 않았다. 혈청 내 cholesterol 함량은 yeast-Cu 처리가 대조구와 methionine-Cu 처리보다 유의하게 낮았지만 chitosan-Cu 처리와는 유의한 차이가 없었다. 혈청 IgG의 함량은 대조구 보다 모든 Cu-chelate 처리구에서 낮게 나타났다. 결론적으로 Cu 137ppm의 대조구 사료에 Cu 100ppm 수준에서 첨가한 Cu-chelates는 이유자돈의 증체량, 사료섭취량과 사료효율에 유의한 영향을 미치지 않았으나, 혈청 내 지질의 조성과 IgG 함량에는 유의한 영향을 미쳤다.

알긴산나트륨 및 첨가제를 함유한 서방성 매트릭스 정제 (Sustained Release Matrix Tablet Containing Sodium Alginate and Excipients)

  • 신성이;이범진;이태섭;허보욱;유승구
    • Journal of Pharmaceutical Investigation
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    • 제26권3호
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    • pp.187-192
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    • 1996
  • The matrix tablet containing sodium alginate and $CaHPO_4$ can release drugs in a controlled fashion from hydrogel with gelling and swelling due to their interaction as water penetrates the matrices of the tablet. The purpose of this study was to evaluate release characteristics of the matrix tablet varying the amount of sodium alginate, $CaHPO_4$ and other excipients such as chitosan, hydroxypropyl methylcellulose (HPMC) and $Eudragit^{\circledR}$ RS100 in the simulated gastric and intestinal fluid. The practically soluble ibuprofen was used as a model drug. The release profiles of matrix tablet in the gastric fluid as a function of sodium alginate/$CaHPO_4$ ratio was not pronounced because of low solubility of drug and stability of alginate matrices. However, release rate of drug from the matrix tablet in the intestinal fluid was largely changed when sodium alginate/$CaHPO_4$ ratio was increased, suggesting that the ratio of sodium alginate/$CaHPO_4$ was an important factor to control the gelling and swelling of the matrix tablet. The incorporation of other excipients into the matrix tablet also influenced the release rate of drug. The chitosan and HPMC decreased the release rate of drug. No release of drug was occurred when $Eudragit^{\circledR}$ RS100 was added into the tablet. The retarded release of matrix tablet when excipients were added resulted from the hindrance of swelling and gelling of the matrix tablet containing sodium alginate and $CaHPO_4$. The hardness and bulk density of the matrix tablet was not correlated with release rate of drug in the study. From these findings, the ratio of sodium alginate and $CaHPO_4$ in the matrix tablet in addition to incorporation of excipients could be very important to control the release rate of drug in dosage form design.

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대형 유리-세라믹 복합 매질 소결체 제조 시 비등방성 변형 특성 평가 (Evaluation of Characteristics of Anisotropic Deformation in Manufacturing of Large-scale Glass-ceramic Composite Sintered Body)

  • 김광욱;손성준;김지민;포스터 리차드;이근영
    • 방사성폐기물학회지
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    • 제18권1호
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    • pp.31-41
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    • 2020
  • 본 연구에서는 우라늄 폐촉매 처리 공정에서 발생하는 우라늄 함유 폐기물 대상으로 유리-세라믹 매질 구조의 대형 디스크 소결체 형태로 제작 시, 최종 제작된 소결체의 비등방향 수축 특성 및 변형율 변화를 연구하였다. 본 연구에서는 최대 직경 40 cm를 갖는 다양한 크기 원형 디스크 형태와 원형 디스크의 1/4 크기의 부채꼴 형 소결체를 제작하여 이들의 비등방성 수축 특성을 평가하였다. 60 MPa 압력하에서 만들어지는 성형체는 소결 시 성형체의 크기 및 형태에 관계없이 높은 등방성 수축하였다. 제조된 전체 소결체에 대한 비등방성율은 평균 1.6%이었고 이때 평균 부피 감용율은 37.4% 이었다. 이러한 결과로부터 국내에서 발생한 우라늄 폐촉매를 처리하기 위한 공정에서 발생하는 우라늄 함유 폐기물은 대형 디스크 형태의 유리-세라믹 매질 형태로 고형화함으로써 높은 안정성과 부피감용 효과를 가지며 200 L 드럼에 포장될 수 있음이 확인되었다.

Arshile Gorky와 Jackson Pollock의 Painting이 현대의상 직물 문양에 미친 영향 (The Influence of Arshile Gorky's & Jackson Pollock's Painting on Modern Fashion)

  • 정흥숙
    • 한국의류학회지
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    • 제16권3호
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    • pp.197-207
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    • 1992
  • Expressionism, is as diverse as the artists invo)ved, in a very broad sense two main tendencies may be noted. The first is that of the Action painters, concerned in different ways with the gesture of the brush and the texture of the paint. It included such major artists as Arshile Gorky, Jackson Pollock, Willem De Keening, and Franz Kline. The other group consisted of the Color Field painters, concerned with the statement of an abstract sign or tranquil image in terms of a large, unified color shape or area. Here must be included Mark Rothko, Barnett Newman, Ad Rdinhardt, as well as, to a degree, Adolph Gottlieb, Robert Motherwell, and Clyf(ord Still. In this paper, 1 selected two artists Arshile Gorky and Jackson Pollock independent charac-teristics and studied the influence of their Action painting on the fabrics of modern fashion. However, it should be noted it was never the intention of the critic Harold Rosenberg, in coining this term, to imply that Action painting was a kind of athletic exercise. Nor is it true that the furious and seemingly haphazard scattering of the paint involved a completely uncontrolled, intuitive act. There is no question that, in the paintings of Jackson Pollock, Arshile Gorky and many of the other Abstract Expressionists, the element of intuition or the accidental plays a large and deliberate part; this was indeed one of the principal contributions of Abstract Expressionism which had found its own inspiration in surrealism's 'psychic automaton'. However, nothing that an experienced and accomplished artist does can be completely accidental. Aside from their intrinsic quality, the spun-out skeins of poured pigments contributed other elements that changed the course of modern painting. There was the concept of the all-over painting, the painting seemingly without beginning or end, extending to the very limits of the canvas and implying an extension even beyond. The feeling of absorption or participation is heightened by the ambiguity of the picture space. The colors and lines, although never punctur-ing deep perspective holes in the surface, still create an illusion of continuous movement, a billowing, a surging back and forth, within a limited depth. To study the influence of Abstract Expressionism on the fabric of modern fashion, 1 selected and examined four fashion magazines: Collezioni published in France, Bazaar in Italy, Gap in Japan and Vogue in the U.S.a. froim January 1989 to June 1991. As a result of this review I found that some fabrics used in modern clothing are printed in a dripping, pouring and splashing style without any meaning or form. Slides included in the presentation show that modern fabrics which are printed in such a style were influenced by Abstract Expressionism. The slides also show that these abstract prints are well suited to modern fashion design.

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4변형 인자에 의한 고강도콘크리트의 내화성능 평가 (Fire Resistance Performance of High Strength Concrete with 4 Deformation Factors)

  • 이태규
    • 한국구조물진단유지관리공학회 논문집
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    • 제16권5호
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    • pp.112-120
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    • 2012
  • 본 연구는 고강도 콘크리트 부재의 고온 하에서의 내화성능을 평가하기 위하여 내부증발 및 크리프를 고려한 해석적 모델들을 제시하였다. 내화성능의 평가는 열팽창, 수분확산, 크리프 모델 및 구조해석을 통하여 폭렬진행과 내화시간의 2가지 단계로 구분하였으며, 해석프로그램을 사용하여 사전재하조건에서부터 화재에 따른 부재의 폭렬 및 파괴까지의 전반적인 해석을 수행하였다. 콘크리트가 화재에 노출되면 콘크리트 표면에서의 수분뿐만 아니라 콘크리트 내부에서의 수분도 수분의 평형 및 전달조건에 의하여 증발이 발생된다. 화재시 콘크리트 부재 내부의 수분변화를 예측하기 위하여 부재 내부의 임의의 위치에서의 상대함수율을 산정하기 위하여 유한요소방식을 적용하였다. 이러한 해석적 모델 및 해석프로그램의 정확성을 검증하기 위하여 해석적 결과와 다른 연구자들에 의한 여러 가지의 실험데이터와 비교하였으며, 그 결과 해석프로그램은 하중, 단면조건, 부재길이, 콘크리트 강도 등 여러 가지 변수들에 대하여 고강도 콘크리트 부재의 내화성능을 해석적으로 잘 평가하고 있는 것으로 나타나고 있다.

단일 첨가제를 이용한 고종횡비 TSV의 코발트 전해증착에 관한 연구 (A Study on the Cobalt Electrodeposition of High Aspect Ratio Through-Silicon-Via (TSV) with Single Additive)

  • 김유정;이진현;박기문;유봉영
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2018년도 춘계학술대회 논문집
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    • pp.140-140
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    • 2018
  • The 3D interconnect technologies have been appeared, as the density of Integrated Circuit (IC) devices increases. Through Silicon Via (TSV) process is an important technology in the 3D interconnect technologies. And the process is used to form a vertically electrical connection through silicon dies. This TSV process has some advantages that short length of interconnection, high interconnection density, low electrical resistance, and low power consumption. Because of these advantages, TSVs could improve the device performance higher. The fabrication process of TSV has several steps such as TSV etching, insulator deposition, seed layer deposition, metallization, planarization, and assembly. Among them, TSV metallization (i.e. TSV filling) was core process in the fabrication process of TSV because TSV metallization determines the performance and reliability of the TSV interconnect. TSVs were commonly filled with metals by using the simple electrochemical deposition method. However, since the aspect ratio of TSVs was become a higher, it was easy to occur voids and copper filling of TSVs became more difficult. Using some additives like an accelerator, suppressor and leveler for the void-free filling of TSVs, deposition rate of bottom could be fast whereas deposition of side walls could be inhibited. The suppressor was adsorbed surface of via easily because of its higher molecular weight than the accelerator. However, for high aspect ratio TSV fillers, the growth of the top of via can be accelerated because the suppressor is replaced by an accelerator. The substitution of the accelerator and the suppressor caused the side wall growth and defect generation. The suppressor was used as Single additive electrodeposition of TSV to overcome the constraints. At the electrochemical deposition of high aspect ratio of TSVs, the suppressor as single additive could effectively suppress the growth of the top surface and the void-free bottom-up filling became possible. Generally, copper was used to fill TSVs since its low resistivity could reduce the RC delay of the interconnection. However, because of the large Coefficients of Thermal Expansion (CTE) mismatch between silicon and copper, stress was induced to the silicon around the TSVs at the annealing process. The Keep Out Zone (KOZ), the stressed area in the silicon, could affect carrier mobility and could cause degradation of the device performance. Cobalt can be used as an alternative material because the CTE of cobalt was lower than that of copper. Therefore, using cobalt could reduce KOZ and improve device performance. In this study, high-aspect ratio TSVs were filled with cobalt using the electrochemical deposition. And the filling performance was enhanced by using the suppressor as single additive. Electrochemical analysis explains the effect of suppressor in the cobalt filling bath and the effect of filling behavior at condition such as current type was investigated.

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시화호에서 채집한 풀망둑 Acanthogobius hasta의 간장 약물대사효소계 및 항산화계의 반응 (Responses in Hepatic Xenobiotic Metabolizing and Antioxidant Enzymes in Javelin Goby Acanthogobius hasta Collected at Shihwa Lake)

  • 이지선;정지현;한창희;심원준;전중균
    • 환경생물
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    • 제26권2호
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    • pp.94-101
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    • 2008
  • 공장 폐수로 인한 오염이 심한 경기 시화호에서 오염정도가 다른 두 지역으로부터 풀망둑을 채집하여 이들의 해독효소계 또는 항산화효소계의 반응을 비교하였다. 해독효소계에서 I상효소로는 CYP, P450R, b5R, EROD를, II상효소로는 GST를 조사하였다. 그리고 항산화효소계로는 CAT, GR, CPx의 활성 그리고 GSH및 CSSG농도를 조사하였다. 그 결과, 오염정도가 심한 지역에서 잡은 어류가 간장 중 P450R, b5R, GST의 활성이 높았으나 EROD활성은 오히려 낮았고 CYP농도는 차이가 없었다. 그리고 이지역에서 잡은 어류는 CAT와 GR의 활성, 비효소적인 항산화계인 CSH와 GSSC농도도 더 높았으나 GTx활성은 오히려 낮았다. 이들 결과는 시화호의 오염된 곳에서 서식하는 풀망둑 Acanthogobius hasta은 상당히 해독효소계가 항진되어 있으며 산화 스트레스도 크게 받고 있음을 보여준다.