• Title/Summary/Keyword: Precusor

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Studies on Mechanism of Antidiuretic Action of N$_G$ Nitro-L-Arginine, Nitric Oxide Synthase Inhibitor, in Dog (Nitric Oxide의 합성 억제제인 N$_G$-Nitro-L-Arginine의 항이뇨작용 기전에 관한 연구)

  • 고석태;유강준
    • Biomolecules & Therapeutics
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    • v.6 no.3
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    • pp.225-231
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    • 1998
  • This studies were performed for investigation of mechanism on central antidiuretic action of L$_{G}$-Nitro-L-arginine (L-NOARG), nitic oxide systhase inhibitor, in dog. Antidiuretic action of L-NOARG infused into the carotid artery was not affected by renal denervation but inhibited by pretreatment with arginine, NO Precusor. Furthermore, L-NOARG inhibited the diuretic action of dopamine induced by hemodynamic development. Above results suggest that antidiuretic actions of L-NOARG mediated by endogenous substances not associated with renal nerve. Therefore, it is demonstrated that those endogenous substances might be associated with NO which mediate the diuretic action of dopamine.e.

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Green Tea Catechin Causes an Weight Loss in Transgenic Mice Over-expressing Carboxyl Terminus of Amyloid Precusor Protein

  • Lim Hwa-J.;Kim Yong-K.;Sheen Yhun-Y.
    • Biomolecules & Therapeutics
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    • v.14 no.2
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    • pp.96-101
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    • 2006
  • Amyloid$\beta(A{\beta})$ has been reported have an effect on the induction of oxidative stress that involves the functional and structural abnormalities in Alzheimer's disease. As a role of a radical scavenger, a green tea treatment was found have some inhibitory effect on the neurodegenerative process. The aim of this study was to determine if green tea catechin (GTC) reduces in transgenic model. To test this, transgenic mice carrying neuronspecific enolase (NSE) controlled C-terminus (105) of APP (APP-C105) were created and treated them with a low ana high dose of GTC for 6 months. Herein, we conclude that transgenic mice expressing NSE/APP-C105 were successfully created and the GTC-treated group exhibited significant reduction in body weight. Thus, GTC might be a good prevention of obesity or good treatment for AD patient.

Secretion of the cloned serratia marcescens nuclease in escherichia coli (Serratia marcescens nuclease의 escherichia coli에서의 분비)

  • 신용철;이상열;김기석
    • Korean Journal of Microbiology
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    • v.28 no.4
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    • pp.297-303
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    • 1990
  • Secretion of Serratia marcescens nuclease by E. coli harboring pNUC4 was investigated. 29.2, 54.2 and 16.6% of total nuclease were observed in culture medium, periplasm, and cytoplasm of E. coli, respectively. To investigate the secretion mechanism of Serratia nuclease by E. coli, secretion kinetics of nuclease was examined in the presences of sodium azide, and energy metabolism inhibitor; procaine, an exoprotein processing inhibitor; and chloramphenicol, a protein synthesis inhibitor. In the presence of sodium azide, periplasmic unclease was gradually decreased and the extracellular nyclease was linearly increased according to the incubation time. Similar results were obtained in presences of procaine and chloramphenicol. From these results, we concluded that two transport processes are involved in nuclease secretion: secretion of nuclease through the inner membrane is occurred by an energy-dependent process and probably requiring precusor processing: secretion of nuclease through outer membrane does not require energy, de novo protein synthesis, and precursor processing.

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Structural properties of PZT multilayer thick films of improved densification (PZT 후막의 치밀성 향상에 따른 PZT 다층 후막의 구조적 특성)

  • Yun, Sang-Eun;Lee, Sung-Gap;Park, Sang-Man;Lee, Young-Hie
    • Proceedings of the KIEE Conference
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    • 2006.07b
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    • pp.1245-1246
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    • 2006
  • Ferroelectric PZT (70/30) thick films were fabricated by the screen printing method. And the PZT (30/70) precusor solution were infiltrated by the spin-coating method on the PZT thick films to obtain a densification. All PZT thick films were sintered at $1050^{\circ}C$ for 10 min. Structural properties, such as crystalline structure, microstructures and compositional ratio, of PZT thick films were investigated with the variation of the number of sol coatings using XRD, SEM and EDS, respectively. All PZT thick films exhibited a perovskite polycrystalline structure without a pyrochloer phase. The thickness of PZT thick films, 4-times screen-printed, was approximately $60{\mu}m$. And the densification of the PZT thick films increased with increasing the number of sol coatings.

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Deposition Technology of Copper Thin Films for Multi-level Metallizations (다층배선을 위한 구리박막 형성기술)

  • 조남인
    • Journal of the Microelectronics and Packaging Society
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    • v.9 no.3
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    • pp.1-6
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    • 2002
  • A low temperature process technology of copper thin films has been developed by a chemical vapor deposition technology for multi-level metallzations in ULSI fabrication. The copper films were deposited on TiN/Si substrates in helium atmosphere with the substrate temperature between $130^{\circ}C$ and $250^{\circ}C$. In order to get more reliable metallizations, effects on the post-annealing treatment to the electrical properties of the copper films have been investigated. The Cu films were annealed at the $5 \times10^{-6}$ Torr vacuum condition and the electrical resistivity and the nano-structures were measured for the Cu films. The electrical resistivity of Cu films shown to be reduced by the post-annealing. The electrical resistivity of 2.0 $\mu \Omega \cdot \textrm{cm}$ was obtained for the sample deposited at the substrate temperature of $180^{\circ}C$ after vacuum annealed at $300^{\circ}C$. The resistivity variations of the films was not exactly matched with the size of the nano-structures of the copper grains, but more depended on the contamination of the copper films.

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Structural properties of PZT multilayer thick films of improved densification (PZT 후막의 치밀성 향상에 따른 PZT 다층 후막의 구조적 특성)

  • Yun, Sang-Eun;Lee, Sung-Gap;Park, Sang-Man;Lee, Young-Hie
    • Proceedings of the KIEE Conference
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    • 2006.07c
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    • pp.1705-1706
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    • 2006
  • Ferroelectric PZT (70/30) thick films were fabricated by the screen printing method. And the PZT (30/70) precusor solution were infiltrated by the spin-coating method on the PZT thick films to obtain a densification. All PZT thick films were sintered at $1050^{\circ}C$ for 10 min. Structural properties, such as crystalline structure, microstructures and compositional ratio, of PZT thick films were investigated with the variation of the number of sol coatings using XRD, SEM and EDS, respectively. All PZT thick films exhibited a perovskite polycrystalline structure without a pyrochloer phase. The thickness of PZT thick films, 4-times screen-printed, was approximately $60{\mu}m$. And the densification of the PZT thick films increased with increasing the number of sol coatings.

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Flavor of Fermented Black Tea with Tea Fungus (Tea Fungus 발효홍차의 향기)

  • 최경호;최미애;김정옥
    • Journal of Life Science
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    • v.7 no.4
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    • pp.309-315
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    • 1997
  • The fermented black tea with tea fungus (FBTF) was prepared by culturing tea fungus biomass in black tea with 10% sucrose (BT) at 30$\circ$ for 14 days. The flavor quality of FBTF was investigated by sensory and chemical analysis, and the results were compared with BT. The data of sensory analysis indicated that fruity, wine-like, sharp-pungent, and vinegar-like flavor notes were increase, while earthy note was reduced during fermentation. GC-MS analysis of volatile compounds collected from FBTF and BT by Tenax trap showed that linalool, liinalool oxide other flavor compounds known as black tea flavor compounds were disappeared. Some major flavor compounds produced during fermentation were acetic acid, ethanol, limonene, $\alpha$-terpineol, and these volatiles may be attributed to the flavor of characteristic FBTF. Biosynthetic pathway for the formation of limonene and $\alpha$-terpineol are proposed through mevalonic acid pathway using acetic acid as precusor and/or through transformation of linalool and linalool oxide.

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One-pot Synthesis of CdS Nanoparticles by Using $Cd(SOCCH_3)_2Lut_2$ Precusor and Their Optical Characteristics ($Cd(SOCCH_3)_2Lut_2$를 이용한 CdS 나노입자의 용이한 합성 방법 및 광학적 특성)

  • Jang, Seunghyun
    • Journal of Integrative Natural Science
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    • v.2 no.4
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    • pp.285-288
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    • 2009
  • A synthetic route for 12 metal thiocarboxylate complex, $Cd(SOCCH_3)_2Lut_2$ [Lut = 3,5-dimethylpyridine (lutidine)], were investigated for their potential to act as precursors for the formation of cadmium sulfide nanoparticles. $Cd(SOCCH_3)_2Lut_2$ were characterized by 1H-NMR spectroscopy. Thermal decomposition of $Cd(SOCCH_3)_2Lut_2$ is expected to undergo thiocarboxylic anhydride elimination to give stoichiometric cadmium sulfide nanoparticles and removes the organic supporting ligands cleanly. Prepared cadmium sulfide nanoparticles were characterized by fluorescence and UV-vis absorption spectroscopy and displayed an emission band at 500 nm with an excitation wavelength of 360 nm.

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Structure and Magnetic Properties on Synthesis Route of Co2Z-type Barium Hexaferrite (Co2Z-type Barium Hexaferrite의 합성방법에 따른 결정구조 및 자기적 특성)

  • Baek, In Seung;Nam, In Tak
    • Journal of the Korean Magnetics Society
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    • v.24 no.1
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    • pp.1-10
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    • 2014
  • $Co_2Z$-type barium ferrites ($Ba_3Co_2Fe_{24}O_{41}$) were synthesized using variation method. First, M-type, $Co_2Y$-type and $Co_2Z$-type synthesized by hydrothermal method. Second, M- and Y-type precursors for synthesis of $Co_2Z$ hexaferrite by hydrothermal and ball milling method. the morphology, structure and magnetic properties of the barium ferrite particles were characterized using XRD, FESEM, VSM, impedance. As a result, Single phase of M-type and $Co_2Y$-type were obtained. Manufactured powders of M+Y ball milling, M+Y hydrothermal were similar to single phase of $Co_2Z$-type hexaferrite, all powders were obtained theoretical magnetization (50 emu/g). The largest initial permeability were obtained $Co_2Z$ hexaferrite synthesized by reagent precusor, With increasing calcination temperature was lowered the initial permeability. In another synthesis didn't almost that little change could be found.

The Emerging Role of Natural Killer Cells in Innate and Adaptive Immunity

  • Kim, Eun-Mi;Ko, Chang-Bo;Myung, Pyung-Keun;Cho, Daeho;Choi, Inpyo;Kang, Hyung-Sik
    • IMMUNE NETWORK
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    • v.4 no.4
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    • pp.205-215
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    • 2004
  • In the early host defense system, effector function of natural killer (NK) cells results in natural killing against target cells such as microbe-infected, malignant, and certain allogenic cells without prior stimulation. NK cell cytotoxicity is selectively regulated by homeostatic prevalence between a repertoire of both activating and inhibitory receptors, and the discrimination of untransformed cells is achieved by recognition of major histocompatibility complex (MHC) class I alleles through inhibitory signals. Although it is well known that the bipotential T/NK progenitors are derived from the common precusor, functional mechanisms in terms of the development of NK cells remain to be further investigated. NK cells are mainly involved in innate immunity, but recent studies have been reported that they also play a critical role in adaptive immune responses through interaction with dendritic cells (DC). This interaction will provide effector functions and development of NK cells, and elucidation of its precise mechanism may lead to therapeutic strategies for effective treatment of several immune diseases.