• 제목/요약/키워드: membrane thickness

검색결과 590건 처리시간 0.032초

소양막이식편이 개의 전층 피부 창상치유에 미치는 효과 (Effects of bovine amniotic membrane graft on healing of full-thickness skin wound in dogs)

  • 황경택;권오경;우흥명;김대용;남치주
    • 대한수의학회지
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    • 제39권3호
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    • pp.645-652
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    • 1999
  • The purpose of the present study was to investigate the effect of bovine amniotic membrane grafts on healing of full-thickness skin wound in dogs. Two $3cm{\times}3cm$ area-matched full-thickness skin wounds were induced bilaterally on the dorsolateral aspect of the trunk of 15 dogs. Chlorhexidine-treated amnion, dried amnion, silver sulfadiazine and 0.9% sterile saline solution were applied on the wound area and examined grossly and histopathologically. Begining 14 days after wounding, amnion applied group had appreciably less amount of inflammatory exudate and hemorrhage than sulfadiazine and saline treated groups. From 14 days after wounding, the degree of wound contraction in amnion groups, especially in the dried amnion group was greater than that of the sulfadiazine and saline treated groups. The percentages of wounds completely healed on 28 days after wounding in saline treated group, chlorhexidine-treated amnion group, dried amnion group and sulfadiazine treated group were 33%, 50%, 83% and 50%, respectively. Microscopically neovascularization and fibrosis were first noticed on 5 days after wounding in the dried amnion group and sulfadiazine treated group, on 7 days in the chlorhexidine-treated amnion group and on 14 days in the saline treated group. Epithelialization in the dried amnion and sulfadiazine treated groups was first noticed on 9 days after wounding, which was faster than that in the other groups. The present study suggests that bovine amniotic membrane, especially dried bovine amnion is effective on healing of full-thickness skin wound in dogs through both wound contraction and epithelialization.

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르포트씨 1급 골절단술을 시행 받은 환자들에서 Cone-beam Computed Tomography를 이용한 수술 전, 후의 상악동의 평가 (Evaluation of Maxillary Sinus Using Cone-beam Computed Tomography in Patients Who Underwent Le Fort I Osteotomy)

  • 이재열;김용일;백영재;황대석
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제34권2호
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    • pp.106-111
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    • 2012
  • Purpose: The aim of this sturdy was to assess the prevalence and change in pathologic findings in the maxillary sinus by using preoperative and postoperative cone-beam computed tomography (CBCT). Methods: The subjects included 83 patients with maxillary sinus abnormalities who underwent orthognathic surgery between January 2010 to December 2010. The CBCT analyses were classified according to the thickness of maxillary sinus membrane; Normal (membrane thickness<2 mm), mucosal thickening (membrane thickness ${\geq}2mm$ and <6 mm), partial opacification (membrane thickness>6 mm but not complete), total opacification, and polypoidal mucosal thickening. The diameters of the maxillary sinus ostium on the coronal cross-sectional view were also calculated. Results: Out of 166 maxillary sinuses in 83 patients, 42 (25.3%) maxillary sinuses before surgery and 37 (22.3%) maxillary sinuses after surgery showed abnormalities. A decrease in the diameters of maxillary ostium was observed after surgery (P<0.05). However, there was no significant difference in mucosal thickness both, preoperatively and postoperatively. Conclusion: The orthognathic surgery didn't deteriorate the maxillary sinus abnormaility. Despite the low prevalence of sinus complications in orthognathic surgery, all the patients should be informed of the possibility of sinusitis that could require the surgical intervention before surgery.

기체크로마토그래프-질량분석기의 실리콘 분리막 인터페이스의 유용성 연구 (Feasibility study of membrane interface for gas chromatograph-mass spectrometry)

  • 강길선;이동수;이화심;박창준
    • 분석과학
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    • 제21권6호
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    • pp.495-501
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    • 2008
  • GC-MS 의 기존 인터페이스와 새로운 인터페이스의 차이점과 유용성을 판단하기 위하여 Agilent 5973 GC-MS의 capillary direct interface를 떼어내고 GC와 질량분석기 사이에 실리콘 membrane을 장착하여 membrane interface GC-MS의 분석 유용성을 조사하였다. 최대 $4.7m{\ell}/min$ 까지 헬륨 운반기체유량을 올릴 때 질량분석기의 진공도는 거의 영향을 받지 않으며, 피이크끌림 현상이 줄어들고 머무른시간이 줄어드는 빠른 분석을 보였다. Membrane 의 두께를 $127{\mu}m$에서 $75{\mu}m$으로 줄일 때 분리능이 향상 되며, membrane interface의 온도를 올릴 때 분리능과 감도가 향상되었다. 그러나 membrane interface GCMS는 질량/전하 비 73, 147에서 바탕이온이 발생하는 것과 기존의 capillary direct insertion interface보다 낮은 감도와 peak tailing에 의한 낮은 분리능의 문제점을 갖는다.

Transport Coefficients across Charged Mosaic Membrane

  • Yang, Wong-Kang
    • Bulletin of the Korean Chemical Society
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    • 제25권5호
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    • pp.665-667
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    • 2004
  • In previous studies, charged mosaic membranes having two different fixed charges in the membrane matrix indicated unique transport behavior such as preferential material transport. In this study, the composite charged mosaic membrane endurable to mechanical pressure in practical application was investigated from the same aspect of solute and solvent transport as before. Lp and ${\omega}$ estimated by taking account of active layer thickness were satisfactorily consistent with those in mosaic membrane without reinforcement. On the other hand, the reflection coefficient s indicated the negative value that suggests preferential material transport.

폐수중 티오시안산이온을 측정하기 위한 계면활성제를 이용한 고분자 막전극 (The Polymer Membrane Electrode by Surfactants for Measuring Continuously Thiocyanate Ion in Wastewater)

  • 최종석;안형환;강안수;우인성;황명환
    • 한국안전학회지
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    • 제6권4호
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    • pp.13-20
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    • 1991
  • Ion-selective electrode responsive to the thiocynate ion prepared by using the quaternary ammonium salts as a active material and PVC as a membrane matrix. The effect of chemical structure and composition of active material, and the membrane thickness on the linear response. the detection limit, and Nernstian slope of the electrode studied. Under the above optimum conditions of membrane, the effect of pH and the selectivity coefficients to various interfering anions were compared and investigated. It was concluded that the functions of thiocynate ion-selective electrode(ISE) were closely related to the chemical structure of the quaternary ammonium salts. The linear response, and the detection limit of the electrode potential increased with the increase of the carbon chain length of the alkyl group in the quaternary ammonium salts in the ascending order of Aliquat 336T, TOAT, TDAT, and TDDAT. The optimum membrane thickness was 0.3mm. The electrode characteristics was better with the decrease of the concentration of active material, and the best concentration was 3 weight percent. The membrane potential was independent of the pH variation in the region from pH 2 to 12. The order of the selectivity coefficients is as follows:Cl $O_4$$^{[-10]}$$I^{[-10]}$ >N $O_3$$^{[-10]}$ >B $r^{[-10]}$$F^{[-10]}$ >C $l^{[-10]}$ >O $A_{c}$ $^{[-10]}$ 〓S $O_4$$^{2-}$.

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멤브레인 케이크 레이어 형성 과정 모사를 위한 수치 모델의 개발 (Development of a Numerical Model for Cake Layer Formation Process on Membrane)

  • 김경호;신재호;이상환;이주희
    • 한국유체기계학회 논문집
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    • 제14권6호
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    • pp.35-44
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    • 2011
  • Membrane filtration has become firmly established as a primary process for ensuring the purity, safety and efficiency of treatment of water or effluents. Several researches have been performed to develop and design membrane systems in order to increase the accuracy and performance of the processes. In this study, a lattice Boltzmann method for the cake layer has been developed using particle dynamics based on an immersed boundary method and the cake layer formation process on membrane has been numerically simulated. Case studies including various particle sizes were also performed for a microfiltration process. The growth rate of the cake layer thickness and the permeation flow rate along the membranes were predicted. The results of this study agreed well with that of previous experiments. Effects of various particle diameters on the membrane performance were studied. The cake layer of a large particle tended to be growing fast and the permeation flow going down rapidly at the beginning. The layer thickness of a small particle increased constantly and the flow rate was smaller than that of the large particle at the end of simulation time.

과염소산 이온선택성 PVC막전극 제작 (Fabrication of Perchlorate Ion Selective PVC Membrane Electrode)

  • 우인성;안형환;강안수
    • 한국전기전자재료학회논문지
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    • 제11권4호
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    • pp.298-305
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    • 1998
  • The PVC membrane electrode for measuring perchlorate ion was developed by incorporating various quaternary ammonium sallts. The effect of chemical structure, the content of active material, the kind of plasticizers, and the membrane thickness on the electrode characteristic such as the linear response range and Nernstian slope of the electrode were studied. It was obtained that the effect of the chemical structure of an active material on the electrode characteristics was improved with increasing the alkyl chain length of the quarternary ammonium salts in the ascending order of Aliquat 336P, TOAP, TDAP, and TDDAP. The optimum membrane composition was 9.09wt% of TDDAP, 30.3wt% of PVC, and 60.6wt% of plasticizer(DBP). And the optimum membrane thickness was 0.45mm at this composition. Under the above condition, the linear response range was $10^{-1}~1.2\times10^{-6}$M, and the detection limit was $5.1\times10^{-7}$M with the Nernstian slope of 57mV/decade of activity of perchlorate ion. The electrode potential was stable within the pH range from 4 to 11. The selectivity coefficient was as shown below: $SCN^->I^-NO_3^->Br^->ClO_3^->F^->Cl^->SO_4^{2-}$

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Decreasing Effect of Lidocaine.HCl on the Thickness of the Neuronal and Model Membrane

  • Park, Sung-Min;Park, Jong-Sun;Kim, Jae-Han;Baek, Jin-Hyun;Yoon, Tae-Gyun;Lee, Do-Keun;Ryu, Won-Hyang;Chung, In-Kyo;Sohn, Uy Dong;Jang, Hye-Ock;Yun, Il
    • The Korean Journal of Physiology and Pharmacology
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    • 제17권4호
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    • pp.253-257
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    • 2013
  • This study examined the mechanism of action of a local anesthetic, lidocaine HCl. Energy transfer between the surface fluorescent probe, 1-anilinonaphthalene-8-sulfonic acid, and the hydrophobic fluorescent probe, 1,3-di(1-pyrenyl) propane, was used to determine the effect of lidocaine HCl on the thickness (D) of the synaptosomal plasma membrane vesicles (SPMV) isolated from the bovine cerebral cortex, and liposomes of the total lipids (SPMVTL) and phospholipids (SPMVPL) extracted from the SPMV. The thickness (D) of the intact SPMV, SPMVTL and SPMVPL were $1.044{\pm}0.008$, $0.914{\pm}0.005$ and $0.890{\pm}0.003$ (arbitrary units, n=5) at $37^{\circ}C$ (pH 7.4), respectively. Lidocaine HCl decreased the thickness of the neuronal and model membrane lipid bilayers in a dose-dependent manner with a significant decrease in the thickness, even at 0.1 mM. The decreasing effect of lidocaine HCl on the membrane thickness might be responsible for some, but not all of its anesthetic action.

메추리의 난각과 난각막의 두께에 관한 연구 (A study on the Thickness of Egg Shell Membrane and Egg Shell in Quail Eggs)

  • 하정기
    • 한국가금학회지
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    • 제7권2호
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    • pp.47-53
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    • 1980
  • 본 시험은 메추리의 난각과 난각막의 두께 변화를 구명하기 위해서, 공시난 520개로부터 다음과 같은 결과를 얻었다. 1) 메추리 란의 외모색에 따라 구분한 사종의 난각은 그 색에 따라서 대반점백색난각. 대반점난각, 소반점보라난각, 소반점베이지난각으로 구분되고, 그 평균 란중은 8.993g, 8.866g, 8.403g, 8,109g이었다. 2) 사종 난각의 평균 두께는 대기점백색락각이 0.171mm, 대반점각이 0.169mm. 소반점베이지난각이 0.160mm, 소반점보라난각이 0.156mm였다. 3) 사종의 난각막의 평균 두께는 대반점 난각이 0.0449mm. 대연점백색난각이 0.0431mm, 소반점베이지난각이 0.398mm 소반점보라난각이 0.0397mm였다. 4) 난각과 난각막의 두께간에서 빈의 상관계수가 나타났으나 유의성은 없었다. 5) 일반적으로 난각의 두께가 닭에 비하여 매우 엷었다. 그러나 난각막의 두께는 대동소이했다.

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