• Title/Summary/Keyword: 반투과성

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DEVELOPMENT OF THREE DIMENSIONAL MEASURING PROGRAM WITH FRONTAL AND LATERAL CEPHALOMETRIC RADIOGRAPHS -PART 1. COMPUTATION OF THE THREE-DIMENSIONAL COORDINATES BY COMPENSATION OF THE ERROR OF THE HEAD POSITION IN ORDINARY NON-BIPLANAR CEPHALOSTAT- (정모 및 측모 두부 방사선 규격사진을 이용한 3차원 계측 프로그램의 개발 -1. 단일 방사선원으로 촬영된 두부 방사선사진의 두부 위치 보정을 이용한 3차원 좌표의 산출-)

  • Lee, Geun-Ho;Lee, Sang-Han;Jang, Hyon-Joong;Kwon, Tae-Geon
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.27 no.3
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    • pp.214-220
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    • 2001
  • The clinical application of the three-dimensional radiographic technique had been limited to standard Broadbent-Bolton cephalometer with biplanar stereoradiography. We developed a new method for compensating the error of head position in ordinary non-biplanar cephalostat. It became to possible to use the three dimensional cephalogram commonly in clinical bases. 1. The method of methemetical compensation of head positioning error in non-biplanar condition was evaluated with dry skull. The error of the method of first and the second trial was $0.46{\pm}1.21$, $0.33{\pm}0.90mm$, which means the error of the head positioning correction in conventional cephalogram was within clinical acceptance. 2. The reproducibility of this system for clinical application was 0.54 mm ($-2.99{\sim}2.26mm$) which defines the absolute mean difference of the first and second trial. Compare to the The landmark identification error $1.2{\pm}1.6mm$, the error of the measurement was within the range of landmark identification error. The result indicates the adequate clinical accuracy of the computation of three-dimensional coordinates by compensation of the error of the head position in ordinary non-biplanar cephalostat.

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Isotopic Determination of Food Sources of Benthic Invertebrates in Two Different Macroalgal Habitats in the Korean Coasts (동위원소 분석에 의한 동해와 남해 연안의 상이한 해조류 군락에 서식하는 저서무척추동물 먹이원 평가)

  • Kang, Chang-Keun;Choy, Eun-Jung;Song, Haeng-Seop;Park, Hyun-Je;Soe, In-Soo;Jo, Q-Tae;Lee, Kun-Seop
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.12 no.4
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    • pp.380-389
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    • 2007
  • Stable carbon and nitrogen isotopes were analyzed in suspended particulate organic matter, macroalgae and macrobenthic invertebrates in order to determine the importance of primary organic matter sources in supporting food webs of rocky subtidal and intertidal macroalgal beds in the Korean coasts. Investigations were conducted at the inter tidal sites within Gwangyang bay, a semi-enclosed and eutrophicated bay, and the subtidal sites of the east coast, a relatively oligotrophic and open environment, in May and June 2005. Water-column suspension feeders showed more negative $\delta^{13}C$ values than those of the other feeding guilds, indicating trophic linkage with phytoplankton and thereby association with pelagic food chains. In contrast, animals of the other feeding guilds, including interface suspension feeders, herbivores, deposit feeders, omnivores and predators, displayed relatively less negative $\delta^{13}C$ values than those of the water-column suspension feeders and similar with that of macroalgae, indicating exclusive use of macroalgae-derived organic matter and association with benthic food chains. Most the macrobenthic species were considered to form strong trophic links with benthic food chains. In addition, the distribution of higher $\delta^{15}N$ values in macrobenthic consumers and macroalgae at the intertidal sites of Gwangyang Bay than those at the subtidal sites of the east coast suggests that anthropogenic nutrients may enhance the macroalgal production at the intertidal sites and in turn be incorporated into the particular littoral food web in Gwangyag Bay. These results confirm the dominant role of macroalgae in supporting rocky subtidal and intertidal food webs in the Korean coasts.

Inhibitory Effect of Steviol and Its Derivatives on Cell Migration via Regulation of Tight Junction-related Protein Claudin 8 (스테비올 및 그 유도체의 세포연접 관련 클라우딘 8 발현 조절을 통한 세포이동 저해효과)

  • Choi, Sun Kyung;Cho, Nam Joon;Cho, Uk Min;Shim, Joong Hyun;Kim, Kee K.;Hwang, Hyung Seo
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.42 no.4
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    • pp.403-412
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    • 2016
  • The tight junction, one of Intercellular junctions, performs a variety of biological functions by bonding adjacent cells, including the barrier function to control the movement of the electrolyte and water. Recent studies have revealed that unusual expression of tight junction-related genes have been shown to be related in cancer development and progression. Recently, there are many reports that control of tight junction proteins expression is closely related to the skin moisture. In this study, we are focusing on the regulating mechanism of tight junction-associated genes by the steviol and its derivatives. Steviol, used as a sweetner, is known to chemical compound isolated from stevia plant. The MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt) assay was carried out in HaCaT cells (human keratinocyte cell line) in order to determine the cytotoxicity. As a result, while steviol showing cytotoxicity from $250{\mu}M$, steviol derivatives are not cytotoxic more than $250{\mu}M$ concentration. We have observed a change in the tight junction protein via quantitative real-time PCR. Claudin 8 among tight junction proteins is only significantly reduced up to 30% in the presence of steviol. In addition, cell migration was inhibited by steviol, not by stevioside and rebaudioside. Finally, we could observe that steviol, not stevioside and rebaudioside, is able to increase the skin barrier permeability through the transepithelial electric resistance (TEER) measurements. These results suggest that the steviol and its derivatives are specifically acts on the tight junction related gene expression, but steviol derivatives are more suitable as a cosmetic material.

Cellular Pathways in Agonist-induced Gallbladder Muscle Contraction in the Cat (고양이의 담낭근 수축에 있어서 세포내 기전)

  • Rhim, Byung-Yong;Kim, Chi-Dae;Kim, Dong-Heon;Biancani, Piero;Behar, Jose
    • The Korean Journal of Pharmacology
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    • v.32 no.1
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    • pp.67-74
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    • 1996
  • Cholecystokinin octapeptide (CCK-8), acetylcholine (ACh) and KCl caused a dose dependent contraction in muscle cells enzymatically digested from cat gallbladder. Maximal contraction was obtained at concentration of $10^{-9}M$ for CCK-8, $10^{-5}M$ for ACh and 20mM for KCl. CCK-8 induced contraction was unaffected in calcium free physiological salt solution (PSS) and was completely blocked by strontium substitution for calcium (p<0.001). In contrast, KCl evoked contraction was blocked in calcium free PSS (p<0.01) but was unaffected by strontium replacement of calcium. The contraction elicited by ACh was only slightly reduced in calcium free PSS (p<0.05) and was unaltered by strontium. Muscle cells permeabilized with saponin contracted in response to inositol 1,4.5-trisphosphate $(IP_3)$ and CCK-8. The contraction was blocked by the calmodulin antagonist CGS 9343B (p<0.001), whereas heparin completely blocked the effect of $IP_3$ (p<0.001). The protein kinase C (PKC) antagonist H7 had no effect on either agonist. We conclude that CCK-8 induced gallbladder muscle contraction is mediated by $IP_3$ dependent intracellular calcium release from intracellular stores and a calmodulin dependent pathway; ACh may utilize both extracellular and intracellular calcium. KCl causes muscle contracrion through influx of extracellular calcium and a calmodulin independent machanism.

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Quality Attributes of Fresh-Cut Green Onion as Affected by Rinsing and Packaging (절단 대파의 품질특성에 미치는 세척 및 포장재의 효과)

  • Hong, Seok-In;Jo, Mi-Na;Kim, Dong-Man
    • Korean Journal of Food Science and Technology
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    • v.32 no.3
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    • pp.659-667
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    • 2000
  • Quality attributes of fresh-cut green onion(Allium fistulosum L.) as affected by rinsing and packaging were investigated in terms of flesh weight, color, viable cell counts, sensory properties during storage at $10^{\circ}C$. Fresh green onions were trimmed, cut, and rinsed with cold water(approximately $5^{\circ}C$) as well as chlorine solution(100 mg/L) and then packaged in low density polyethylene film pouches of $63\;{\mu}m$ thickness. Rinsing treatments with cold water or chlorine solution did not significantly influence changes in microbial populations but sensory characteristics, resulting in cut green onions of better visual quality as compared to the control without rinsing. Fresh-cut green onions were also rinsed with cold water and packaged in sealed bags of low density polyethylene films with different thickness(22, 36, $63\;{\mu}m$), and stored at $10^{\circ}C$ for 18 days. Thickness of polyethylene film was a significant factor for microorganisms populations and sensory attributes. Mesophilic aerobic bacterial count after 13 days for the control, packed in punched film bags, was $3.07{\times}10^6}$ CFU/g, while those for samples in hermetically sealed bags ranged only $1.74{\sim}2.02{\times}10^5}$ CFU/g. Gas composition within the sealed packages changed from normal air to about $1.3{\sim}5.4%\;O_2$ and $4.0{\sim}8.0%\;CO_2$ after 13 days of storage. Particularly, the visual sensory quality of cut green onion samples was retained better in polyethylene film bags of $63\;{\mu}m$ thickness(gas transmission rate: 600 $O_2\;mL/day{\cdot}m^2{\cdot}atm;\;2,500\;CO_2\;mL/day{\cdot}m^2{\cdot}atm$) than in the others.

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