• 제목/요약/키워드: active agents

검색결과 659건 처리시간 0.038초

N-Triethoxy silyl propyl quinine urethane을 도입한 유-무기 복합 코팅제의 내후성 (Weatherability of Organic-Inorganic Hybrid Coating Agents with N-Triethoxy silyl propyl quinine urethane)

  • 이만성;조남주
    • 접착 및 계면
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    • 제2권2호
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    • pp.20-27
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    • 2001
  • 투명 플라스틱 중에서 가장 많이 이용되고 있는 재료의 하나로 폴리카보네이트 수지가 알려져 있다. 이 수지는 투명 플라스틱 중에서도 굴절률이 1.584로 유리의 굴절률에 상응하는 수치를 가지고 있어 렌즈, 창소재 등 광학적 용도에 있어서 유리의 대체품으로서 호응이 크다. 그러나 장점에 반하여 표면 경도가 낮기 때문에 마찰에 의해 긁히기 쉽고 용제 등에 대한 내성도 나쁜 편이다. 특히 옥외 창 재료로 사용할 경우에는 자외선의 흡수에 따른 표면의 황변이 심각한 문제가 되어 사용상에 한계를 가지고 있다. 본 연구에서는 실리콘 하드 코팅제의 우수한 내마모성 및 광학 특성을 가지며 또한, 무기 실록산 네트워크에 자외선 흡수 능력을 가진 유기 실란을 도입시켜 폴리카보네이트 수지의 취약한 표면을 효율적으로 보호하면서 내후성 또한 뛰어난 표면 보호 코팅제를 제공하기 위하여 quinine과 3-isocyanato propyl triethoxy silane(3-IPTES) 으로부터 N-triethoxy silyl propyl quinine urethane (TESPQU)을 합성하였다. 이 물질을 methyl triethoxy silane(MTES) 과 공가수분해 후 축합시켜 실록산 네트워크 속으로 도입시켰다. 또한 benzophenone 계통의 자외선 흡수제를 유가실란 축합물에 단순 배합한 경우와 비교하였다. 주사슬에 UV에 안정한 형태의 유가 실란, TESPQU를 도입한 경우 좋은 내후성을 나타냄을 확인할 수 있었다.

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Brazilin Augments Cellular Immunity in Multiple Low Dose Streptozotocin (MLD-STZ) Induced Type I Diabetic Mice

  • Yang, Kyoung-Mee;Jeon, Sun-Duck;So, Dhong-Soo;Moon, Chang-Kiu
    • Archives of Pharmacal Research
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    • 제23권6호
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    • pp.626-632
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    • 2000
  • Brazilin, an active principle of Caesalprenia sappan, was examined for its immunopotentiating effects in multiple low dose streptozotocin (MLD-STZ) induced type diabetic mice. Brazilin was intraperitoneally administered for 5 consecutive days to MLD-STZ induced type 1 diabetic mice. Delayed type hypersensitivity, Con A-induced proliferation of splenocytes and mixed lymphocyte reaction, which had been decreased in diabetic mice, were significantly recovered by the administration of brazilin. Brazilin increased IL-2 production without affecting suppressor cell activity. Con A-induced and IL-2-induced expression of high affinity IL-2 receptors were also enhanced by brazilin. These results indicate that brazilin augments cellular immune responses, which are suppressed in the MLD-STZ induced type I diabetic mice, by increasing IL-2 production and responsiveness of immune cells to IL-2.

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Role of Micronutrients in Skin Health and Function

  • Park, Kyungho
    • Biomolecules & Therapeutics
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    • 제23권3호
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    • pp.207-217
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    • 2015
  • Skin is the first line of defense for protecting our bodies against external perturbations, including ultraviolet (UV) irradiation, mechanical/chemical stress, and bacterial infection. Nutrition is one of many factors required for the maintenance of overall skin health. An impaired nutritional status alters the structural integrity and biological function of skin, resulting in an abnormal skin barrier. In particular, the importance of micronutrients (such as certain vitamins and minerals) for skin health has been highlighted in cell culture, animal, and clinical studies. These micronutrients are employed not only as active compounds in therapeutic agents for treating certain skin diseases, but also as ingredients in cosmetic products. Here, the author describes the barrier function of the skin and the general nutritional requirements for skin health. The goal of this review is to discuss the potential roles and current knowledge of selected micronutrients in skin health and function.

Effect of Diallyl Disulfide on the Hepatic Glutathione S-Transferase Activity in Rat : Diallyl Disulfide Effect on the Glutathione S-Transferase

  • Huh, Keun;Lee, Sang-Il;Park, Jong-Min;Kim, Seok-Hwan
    • Archives of Pharmacal Research
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    • 제9권4호
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    • pp.205-209
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    • 1986
  • Glutathione s-transferase in thought to play a key role in initiating the detoxication of potential alkylating agents, including pharmacologically active compounds. It is widely accepted that garlic contained allin which is converted to allicin by allinase. Allicin is easily degraded to diallyl disulfide and other components. This report attempted to observe the effect of diallyl disulfide on some biological activities. It was observed that the activity of serum transaminase was not changed by the treatment of diallyl disulfide. The liver cytosolic glutathione s-transferase was significantly increased. where as the microsomal glutathione s-transferase was not increased.

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Inhibitory Effect Against Akt by Cyclic Dipeptides Isolated from Bacillus sp.

  • Hong, Sung-Won;Moon, Byoung-Ho;Yong, Yeon-Joong;Shin, Soon-Young;Lee, Young-Han;Lim, Yoong-Ho
    • Journal of Microbiology and Biotechnology
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    • 제18권4호
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    • pp.682-685
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    • 2008
  • Among thirteen strains of the genus Bacillus isolated from Shrimp-jeotkal in our laboratory, a strain BA34 showing good antifungal activity against Phytophthora infestans in a previous experiment was tested for the inhibitory effect against Akt, protein kinase B. Since Akt is known to play an important role in controlling apoptosis, its inhibitors can be used as potential apoptosis-inducing agents in the treatment of cancer. Two active compounds were isolated and their structures were determined. They have similar structures, despite showing different inhibitory effects. In order to elucidate the reasons for these different effects, three-dimensional studies were carried out.

Facile Synthesis of New Pyrazolopyrimidine Derivatives of Potential Biosignificant Interest

  • Aly, Aly A.;El-Karim, Iman A. Gad
    • 대한화학회지
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    • 제55권5호
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    • pp.781-786
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    • 2011
  • An easy and efficient route for the synthesis of some imidazo[1,2-c]pyrazolo[4,3-e]pyrimidines 3-6, imidazo[1,2-c]pyrazolo[4,3-e]triazine 8, pyrazolo[4,3-e]triazolo[1,5-c]pyrimidines 12-15 and pyrazolo-[3',4':4,5]pyrimido[1,6-b]triazines 16, 17 was described through the reaction of readily available 5-aminopyrazole-4-carbonitrile 1 with different reagents. The in vitro antimicrobial activity of some synthesized compounds was examined. Most of the tested compounds proved to be active as antibacterial and antifungal agents.

유행인가? 실행(Praxis)인가? - 가족연구에서의 다문화가족 담론분석과 성찰 - (Trends or Praxis? - Discourse Analysis and Reflection of Multicultural Families in Family Studies -)

  • 최연실
    • 가정과삶의질연구
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    • 제27권6호
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    • pp.171-187
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    • 2009
  • The purpose of this study is to identify and illustrate academic trends that can be gleaned from family studies on multicultural families in Korea, and to gain a suggestion of the relatedness between discourse and practice by reviewing research in that field. The results of discourse analysis are as follows: First, research on multicultural families in family studies set limited focal subjects. Second, the research accepts assimilationism as a primary multicultural policy set forward by the Korean Government. Third, the research reflects a more or less conservative consciousness of family maintenance. Fourth, there have been some changes in perspectives from the perception of immigrant women in multicultural families as passive minorities to more active agents. Lastly, the research perceives family life in multicultural families as a project for practice.

아미노당(糖) 유도체(誘導體)의 미셀형성(形成)에 관(關)한 동력학적(動力學的) 연구(硏究) (Thermodynamics of Micellzation of Aminosugar Derivatives)

  • 남기대;이창섭;박관선
    • 한국응용과학기술학회지
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    • 제8권1호
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    • pp.85-89
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    • 1991
  • The thermodynamics of micellization of a new series of ionic surface-active agents, dimethyl alkyl-2-deoxy-2-epi-inosityi-ammonium chlorides, has been examined, A minimum in the critical micelle concentration versus temperature has been observed at $25^{\circ}C$ It has been found that the standard entropy of micellization is always positive showing that miceliization is governed by the gain in entropy associated with the removal of the monomer from an aqueous environment to the micelle over a $15^{\circ}C$ to $45^{\circ}C$ temperature while governed by enthalpy directed process below $25^C{\circ}$.

Enterococcus faecalis RKY1 이 생산하는 Fumarate Reductase의 특성 (Characteristics of Fumarate Reductase from Enterococcus faecalis RKY1)

  • 박미란;김도만;류화원;이진하
    • KSBB Journal
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    • 제15권3호
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    • pp.318-322
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    • 2000
  • An oxygen-sensitive fumarate reductase has been purified from the cytosol fraction of the Enterococcus faecalis RKY1 grown anaerobically on a defined medium containing glycerol and fumarate. A major portion of the purification was performed with employing Triton X-100 and reducing agents by Phenyl-sepharose CL-4B DEAE-sepharose and Dephadex G-150 The final activity was 0.42 unit/mg. The deduced molecular mass of active band was 66 kDa. The optimal pH and temperature for the activity were 7.0 and 38$^{\circ}C$ respectively. The enzyme activity was not affected by 1mM metal ions such as bacl2 $.$2H2O HgCl2 MnCl2$.$4H2O ZnCl2 CuCl2$.$2H2O Mgcl2$.$6H2O FeSo4$.$7H2O and by EDTA. Partially purified enzyme ws yellow in color ; spectroscopic study indicated the presence of flavins as a cofactor.

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정신과약물의 혈중농도 측정방법 및 임상적 적용 : 항우울제를 중심으로 (Measurement for Blood Levels of Psychotropics and Clinical Applications : Antidepressants)

  • 김승현;이민수
    • 생물정신의학
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    • 제2권1호
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    • pp.20-27
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    • 1995
  • Therapeutic montitoring of drugs is a well established clinical 1001. However, the state of art is somewhat less advanced for psychotrpoic agents than it is for other classes of drugs, for several reasons. Most psychotropics have large volumes of distribution and achieve relatively low plasma concentrations following therapeutic doses. Many have one or more active metabolites. As a consequene, the analytical methodologies are often complex and not always reliable; well-controlled clinical studies are difficult to perform; and therapeutic ranges have been difficult to establish. Despite these limitations, prudent and selective monitoring of serum drug concentrations, particularly of the tricyclic antidepressants can be helpful in clinical management. This paper presents an overview of clinical and mothodological issues surrounding the utility of blood level measurement.

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