• 제목/요약/키워드: tubular membrane

검색결과 189건 처리시간 0.027초

Damage Estimation for Offshore Tubular Members Under Quasi-Static Loading (준정적하중(準靜的荷重)을 받는 해양구조물(海洋構造物)의 원통부재(圓筒部材)에 대한 손상예측(損傷豫測))

  • Paik, Jeom-K.;Shin, Byung-C.;Kim, Chang-Y.
    • Bulletin of the Society of Naval Architects of Korea
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    • 제26권4호
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    • pp.81-93
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    • 1989
  • The present study attempts to develop the theoretical model for the damage estimation of offshore tubular members which are subjected to the accidental impact loads due to collision, falling objects and so on. For the reasons of the simplicity of the problem being considered, however, this paper postulates that the accidental load can be approximated to be the quasi-static one, in which dynamic effects are negelcted. Based upon the theoretical and experimental results which are obtained from the present study as well as the existing literature, the load-displacement relations taking the interaction effect between the local denting and the global bending deformation into account are presented in the explicit form when the concentrated lateral load acts on the tubular member whose end condition is supposed to be rotation ally free and axially restrained, in which membrane forces develop. Thus, the practical estimation of damage deformation for the local denting and the global bending damage of tubular members against the accidental loads is possible and also the collision absorption capability of the member can be calculated by performing the integration of the area below the given load-displacement curves, provided that all the energy is dissipated to the deforming the member itself.

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STUDY ON EXPRESSION OF GLYCOSAMINOGLYCAN IN ADENOID CYSTIC CARCINOMA (선양낭성암종(Adenoid Cystic Carcinoma)에서의 Glycosaminoglycan의 발현에 관한 연구)

  • Son, Chang-Won;Kim, Kyung-Wook;Kim, Chul-Hwan
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제30권4호
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    • pp.271-281
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    • 2004
  • Adenoid cystic carcinoma is malignant tumor in salivary gland, and its behavior is very invasive. Of all malignant tumor adenoid cystic carcinoma is occured in frequency of 4.4% in major salivary gland, and 1.29% in minor salivary gland. Histopathologically, adenoid cystic carcinoma is characterized by a cribriform appearance, and tubular form and solid nest type tumor can be seen. The tumor cell structure composed of modified myoepithelial cell, and basaloid cell. Extracellular matrix of this tumor cell contains variable ground substance with basement membrane component. Basement membrane matrix composed of collagen fibers, glycoproteins, proteoglycans, and its function is well known that it participate in differentiation, proliferation, and growth of tumor cell. Basement membrane molecule is essential for invasion of peripheral nerve, blood vessel, skeletal muscle in tumor cell of adenoid cystic carcinoma. In many studies, the tumor cell of adenoid cystic carcinoma containing modified myoepithelial cell participate in synthesis of proteoglycan. In this study, tissue sample of adenoid cystic carcinoma of human salivary gland were obtained from 15 surgical specimen, and all specimen were routinely fixed in 10% formalin and embedded. Serial $4-{\mu}m$ thick sections were cut from paraffin blocks. the histopathologic evaluation was done with light microscopy. And, the immunohistochemical staining, characteristics of glycosaminoglycan were observed. For biochemical analysis of glycosaminoglycan, isolation of crude glycosaminoglycan from tumor tissue and Western bolt analysis were carried out. With transmission electomicroscopy, tumor cell were observed. Biologic behavior of adenoid cystic carcinoma was observed with distribution and expression of basement membrane of glycosaminoglycan in tumor cells, The results obtained were as follows: 1. In immunohistochemical study, chondroitin sulfate is postively stained in tumor cell and interstitial space, dermatan sulfate is weakly stained in ductal cell. But keratan sulfate is negatively stained. 2. In immunohistochemical study, heparan sulfate is strong positive stained in tumor cell and basement membrane, especially in invasion area to peripheral nerve tissue. 3. In transmission electromicroscpic view, the tumor cells are composed modifed myoepithelial cells, and contains many microvilli and rough endoplasmic reticulum. 4. In Western blot analysis, the expression of glycosaminoglycan is expressed mostly in heparan sulfate. From the results obtained in this study, tumor cell of adenoid cystic carcinoma is composed modified myoepithelial cell, and glycosaminoglycan of basement membrane molecule of heparan sulfate and chondroitin sulfate mostly participate in the development and invasiveness of adenoid cystic carcinoma by immunohistochemical study and western blot analysis.

The Preparation and the Gas Permeation Characteristics of the Soluble Polyimides (용해성 폴리이미드의 제조 및 기체투과특성)

  • Chun, Kyoung-Yong;Kim, Han-Sung;Han, Hak-Soo;Joe, Yung-il
    • Applied Chemistry for Engineering
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    • 제9권2호
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    • pp.306-310
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    • 1998
  • The soluble polyimides(PMDA/diamine/dianhydride) were prepared and investigated. After coating the prepared PMDA/diamine/dianhydride solution into the commercial tubular alumina ceramic membranes, gas permeation characteristics was investigated. $T_g{\prime}s$ of the polyimides were in the range of $337{\sim}358^{\circ}C$ and thermal stability was good. The polymer was soluble in NMP, DMAc, DMSO, THF, and m-cresol. The adhesion between the alumina membrane and the soluble polyimide was excellent. The soluble polyimide/alumina membranes containing 6FDA showed the highest permeability among others. The permeability of nitrogen of PMDA/1,3PDA/6FDA-alumina membrane was about $7.6{\times}10^{-7}(mol/m^2{\cdot}Pa{\cdot}s)$ in the gas permeation experiments. The ideal separation factor of $O_2/N_2$ and $H_2/N_2$ in PMDA/1,3PDA/6FDA-alumina membrane were 6.19, and 70.0, respectively.

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Thin Glomerular Basement Membrane Disease with Herlyn-Werner-Wunderlich Syndrome : Uterus Didelphys, Blind Hemivagina and Ipsilateral Renal Agenesis (비박형 사구체 기저막 질환이 동반된 중복 자궁 일측성 폐쇄질 및 동측 신장 무형성 증후군 ( Herlyn - Werner- Wunderlich syndrome ) 1례)

  • Kim, Myoung-Soo;Park, Yong-Jun;Park, Young-Jun;Park, Noh-Hyuck;Song, Ji-Sun;Kim, Pyung-Kil
    • Childhood Kidney Diseases
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    • 제11권2호
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    • pp.299-305
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    • 2007
  • Herlyn-Werner-Wunderlich syndrome(HWWs) is a rare variant of Mullerian ductal anomalies characterized by the presence of a hemivaginal septum, a didelphic uterus, and ipsilateral renal agenesis. It usually presents after menarche with progressive pelvic pain, and palpable mass due to hemihematocolpos. If a cystic mass is detected behind the urinary bladder in children, in association with the absence of a kidney, the diagnosis of uterus didelphys with imperforate vagina and hydrocolpos should be considered. When renal agenesis is found in asymptomatic children, the small size and the tubular shape of the uterus makes it almost impossible to evaluate uterine anomalies, so follow-up should be performed until the end of puberty. Appropriate preoperative diagnosis and treatment will prevent unnecessary procedures and offer relief of symptoms. We report one case of didelphic uterus with blind hemivagina and ipsilateral renal agenesis with biopsy- proven thin glomerular basement membrane disease which is not related to the above syndrome.

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Morphological studies on the dendritic cells in the mammary gland II. Electron microscopic observations (유선조직내에 출현하는 dendritic cell의 형태학적 연구 II. 전자현미경적 관찰)

  • Ryu, Si-yun;Lee, Cha-soo
    • Korean Journal of Veterinary Research
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    • 제28권2호
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    • pp.241-249
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    • 1988
  • In order to investigate the morphological characteristics of dendritic cells in the mammary gland of the mouse (C57 BL/6), rat(W), rabbit and cat, the fine structures of the dendritic cells have been observed by the electron microscope. The results obtained were summarized as follows: The dendritic cells with the well-developed processes had an irregular shape, and lacked the desmosome. The pinocytotic vesicles and tubular invaginations of the cell membrane were frequently observed, and the mitochondria with the well-developed cristae were located in the restricted region in the cytoplasm of the dendritic cells. The nuclei of dendritic cells were indented, In the mice and rats, the dendritic cells had a few Langerhans cell granules(Birbeck granules). From the above results, it is confirmed that the ATPase-positive dendritic cells in the mammary gland are the Langerhans cells.

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Advanced Water Treatment of High Turbidity Source by Hybrid Process of Ceramic Microfiltration and Activated Carbon Adsorption: Effect of Water-back-flushing Time and Period (세라믹 정밀여과 및 활성탄 흡착 혼성공정에 의한 고탁도 원수의 고도정수처리: 물 역세척 시간 및 주기의 영향)

  • Park, Jin-Yong;Lee, Hyuk-Chan
    • Membrane Journal
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    • 제19권1호
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    • pp.7-18
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    • 2009
  • In this study, we used the hybrid module that was composed of granular activated carbons (GAC) packing between module inside and outside of tubular ceramic microfiltration membrane for advanced drinking water treatment. Instead of natural organic matters (NOM) and fine inorganic particles in natural water source, modified solution was prepared with humic acid and kaolin. We were investigated effect of water-back-flushing time (BT) and water-back-flushing period (FT) to minimize membrane fouling and to enhance permeate flux (J) in the hybrid process, and tried to find the optimal operating conditions. As a result, resistance of membrane fouling ($R_f$) was slightly decreased according to increasing BT. Also, the shorter FT was the more effective to reduce $R_f$ and to enhance J because of frequent water-back-flushing. However, the optimal BT and FT conditions were 10 sec and 8 min respectively when operating costs were considered. Then, the optimal conditions derived from our experiments of modified solution were applied to lake water treatment. As a result, average treatment efficiencies of turbidity, $UV_{254}$ absorbance, and $COD_{Mn}$ were very high as 99.11%, 91.40% and 89.34%, respectively, but that of TDS was low as 30.05%.

Morphology and Ultrastructure of Gill for Lateolabrax japonicus (농어(Lateolabrax japonicus) 아가미의 형태와 미세구조)

  • Kang, Chung-Bae;Kim, Jin-Koo;Kim, Jae-Won
    • Applied Microscopy
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    • 제39권4호
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    • pp.319-324
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    • 2009
  • Morphology of the gill in Lateolabrax japonicus was investigated after staining the gill, as a result, we found the gill is composed of gill raker, gill arch, gill filament and gill lamellae. The number of gill raker was 7~10 in the upper and 13~18 in the lower. Ultrastructure of the gill in Lateolabrax japonicus were examined by means of the light and transmission electron microscopes. The gill have primary filament and secondary filament (lamellae). The following cells are identified and described: pavement cell, pillar cell, blood cell, mucose cell and chloride cell etc. Simple epithelial layer consists of squamous epithelium contained large nucleus, intracellular organelles etc. and the surface is covered with some of microridges. The lamella pillar structures are characterized by the axial microtubules and lateral membrane interdigitations. The mucous cells were globular in shape, and had almost the mucous granules of same size with various electron density. Chloride cells contain a lot of mitochondria and specifically developed tubular systems.

Effect of Salviae Radix on renal tubular reabsorption in rabbits with mercury-induced acute renal failure (수은으로 유발된 토끼의 신장 기능 손상에 대한 단삼(丹參)의 효과)

  • Hwang, Young-Geun;Jeong, Ji-Cheon
    • The Journal of Internal Korean Medicine
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    • 제21권2호
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    • pp.227-234
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    • 2000
  • 독성약물에 의한 급성신부전시 세뇨관세포의 물질 재흡수 장애에 대한 단삼(丹參) 추출액의 효과를 조사하였다. 토끼에 수은(HgCl2)을 10 mg/kg되게 피하 주사하여 급성신부전을 유발하였고, 단삼(丹參) 추출액의 효과는 수은을 주사하기 전 7일 동안 0.05% 액(液) 0.3 g/kg 용량을 경구 투여하여 관찰하였다. 수은을 주사하기 전 24시간 동안 요와 혈액을 채취하여 신장기능을 측정하여 대조기간(basal period)의 값으로 하였고, 수은을 주사한 후 24시간 동안 요와 혈액을 얻어 수은에 의한 신장기능 변화를 평가하였다. 수은을 처리한 후 사구체여과율이 대조값에 비해 감소하였고, 혈청내 creatinine 농도가 증가하였다. 이러한 결과들은 수은이 급성신부전을 유발하였음을 가리킨다. 수은을 처리한 동물에서 포도당 및 인산의 배설분율이 증가하였고, 이러한 변화는 brush-border membrane에서 물질의 이동장애와 Na-pump 활성의 감소에 기인하였다. 수은을 주사한 동물의 신장피질 절편에서 유기이온인 PAH와 TEA 이동이 억제되었다. 토끼의 신장조직에서 지질의 과산화가 수은을 주사한 후 증가하였다. 단삼(丹參) 추출액을 전 처리한 후 수은을 주사한 경우 수은에 의해 유발된 사구체여과율의 감소와 혈청내 creatinine 농도 증가 현상이 유의하게 완화되었다. 수은에 의한 세뇨관에서 물질의 재흡수 장애가 단삼(丹參) 추출액의 전처리에 의해 방지되었다. 단삼(丹參) 추출액은 수은에 의한 지질의 과산화를 억제하였다. 수은에 의한 급성신부전은 항산화제로 잘 알려진 DPPD에 의해 방지되었다. 이상의 결과를 종합하면 생체실험결과 수은에 의한 급성신부전의 유발과정에 지질의 과산화가 중요한 역할을 할 가능성을 보이고 있고, 단삼(丹參) 추출액은 수은에 의한 급성신부전을 방지하는 효과를 가지고 있으며, 그 효과는 단삼(丹參)의 항산화작용에 기인(起因)할 가능성이 많다.

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Effect of Cisplatin on Sodium-Dependent Hexose Transport in LLC-$PK_1$ Renal Epithelial Cells

  • Lee, Suk-Kyu;Kim, Jee-Yeun;Yu, Tai-Hyun;Kim, Kyoung-Ryong;Kim, Kwang-Hyuk;Park, Yang-Saeng
    • The Korean Journal of Physiology and Pharmacology
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    • 제1권1호
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    • pp.35-43
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    • 1997
  • Cis-dichlorodiammine platin${\mu}M$II (Cisplatin), an effective chemotherapeutic agent, induces acute renal failure by unknown mechanisms. To investigate direct toxic effects of cisplatin on the renal proximal tubular transport system, LLC-$PK_1$ cell line was selected as a cell model and the sugar transport activity was evaluated during a course of cisplatin treatment. Cells grown to confluence were treated with cisplatin for 60 min, washed, and then incubated for up to 5 days. At appropriate intervals, cells were tested for sugar transport activity using ${\alpha}-methyl-D-[^{14}C]glucopyranoside$ (AMG) as a model substrate. In cells treated with 100 ${\mu}M$ cisplatin, the AMG uptake was progressively impaired after 3 days. The viability of cells was not substantially changed with cisplatin of less than 100 ${\mu}M$, but it decreased markedly with 150 and 200 ${\mu}M$. In cisplatin-treated cells, the $Na^+$ -dependent AMG uptake was drastically inhibited with no change in the $Na^+$ -independent uptake. Kinetic analysis indicated that Vmax was suppressed, but Km was not altered. The $Na^+$ -dependent phlorizin binding was also decreased in cisplatin-treated cells. However, the AMG efflux from preloaded cells was not apparently retarded by cisplatin treatment. These data indicate that the cisplatin treatment impairs $Na^+$ -hexose cotransporters in LLC-$PK_1$ cells and suggest strongly that defects in transporter function at the luminal plasma membrane of the proximal tubular cells constitute an important pathogenic mechanism of cisplatin nephrotoxicity.

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Antibody-dependent rat macrophage-mediated damage Into the excysted metacercariae of Paragonimus westeymani in vitro (폐흡충(Paragonimus westermani) 감염시의 세포 면역학적 장어 기전)

  • 정평림;장재경;소진천
    • Parasites, Hosts and Diseases
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    • 제29권1호
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    • pp.43-54
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    • 1991
  • An in vitro immune effector mechanism against the target encysted metacercariae of Paragonimus westermani was demonstrated in the rat system. Peritoneal exudate cells, mainly macrophages from normal rats, showed adherence to and killing of encysted metacercariae of p. westermani in the presence of complement-independent serum from rats infected with Paragonimus metacercariae. These reactions were specific for the excysted metacercariae, as tissue-migrating juvenile worms were not affected. Damage of encysted metacercariae of p. westermani due to antibody and macrophages was assessed by morphological observation, by cell adherence reaction and by the use of vital dyes. frypan blue dye exclusion proved to be a reliable indicator of judging metacercarial viability. Electron microscopic studies demonstrated that macrophages reacted with fusty material on the tegumental surface and fine structures in the syncytium of the parasites. The tubular tunnels formed between the basement membrane and muscle layers of the damaged parasites were also noticeable. The relevance of these findings to cellular immunity in the early paragonimiasis was discussed.

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