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      • SCOPUSKCI등재
      • SCOPUSKCI등재

        방사선조사 후 유표피암종세포내 칼슘농도의 변화와 apoptosis 발현에 관한 연구

        이삼선,문제운,허민석,박태원,유동수,최순철 大韓口腔顎顔面 放射線學會 1999 Imaging Science in Dentistry Vol.29 No.1

        Purpose: Ionizing radiations have been reported as an apoptosis initiating stimulus in various cells and it has established that sustained elevations in [Ca²+] can lead to DNA fragmentation by Ca²+-dependent endonucleases, ultimately resulting in apoptotic cell death. The previous experiments have been reported by using primarily thymocytes and lymphocytes and the change of [Ca²+] was measured only by minutes or hours respectively. We need to evaluate [Ca²+] in both several minutes and hours after irradiation of radiation of radiation therapy and verify the apoptotic cells. Materials and Methods: We have measured [Ca²+] in human gingival epitheloid cancer cell with 10 Gy irradiation, at minutely intervals and hourly intervals using digitized video-intensified fluorescence microscopy and the fluorescent Ca²+ indicator dye, fura-2. In order to find out that the transient rise in [Ca²+] could induced apoptosis, cells were incubated for 1 hour at 37℃ with TdT enzyme, rinsed and resuspended containing fluorescence and observed under a confocal fluorescence microscope. MTT assay was done to determine cell activity and LDH assay was done to determine the amount of necrotic cells. Results: After irradiation, the transient and temporal increasing of [Ca²+] in the KB cells was founded. Though, there was no change in the intracellular [Ca²+] at 30 minutes and 2 hours after irradiation. We could detect of DNA fragmented cells at 4 hours after 10 Gy irradiated cells. There were no significant differences between 4 hour, 1 day, 3 day cells. There were no significant differences in MTT and LDH assay between the irradiated group and the control group after 4 hours and 1 day. Though after 3 days there were differences in MTT and LDH assay between the irradiated group was significantly decreased than the control group, in LDH assay the number of necrotic cell death of the irradiated was higher than the control group. Conclusion: In KB cells there were incipient and temporal increasing of the [Ca²+] with 10 Gy irradiation and the apoptosis was founded from 4 hours later which was earlier than seeing of the change of the amount of the cellular ability and necrosis.(J Korean Oral Maxillofac Radiol 1999:29:109-117)

      • KCI등재

        라오스의 벼 생산 현황과 문제점

        이문희,최경진,이정일,정남진,양원하,김제규 한국국제농업개발학회 2001 韓國國際農業開發學會誌 Vol.13 No.4

        Rice is the single most important crop in Lao PDR. In the 2000 rice production year, total rice production in the Laos reached 2.2 million tons. This is regarded as sufficient to provide national self-sufficiency. The rice harvested area in 2000 was approximately 719,500ha and represented 80% of cropped land area. Approximately 82% of production was from wet season cropped and 18% was from the irrigated dry season. Grain yield per unit area vary from 1.68 to 4.39 ton/ha in the wet season environment. However, the highest grain yield (4.39 ton/ha) obtained from the dry season irrigated crop. Higher yields and reduced year variation in production can be expected with the further intensification of production systems in the low land environments. However, further imporvements in production will be dependent on higher levels of inputs and further alleviation of some the production constraints.

      • Girder의 강성을 고려한 복합 재료 교량 상판의 구조 거동

        원치문,박제선,이정호,심도식 江原大學校 産業技術硏究所 1998 産業技術硏究 Vol.18 No.-

        Many of the bidge and building floor systems, including the girders and cross-beams, also behave a similar special orthotropic plates. Such plates are subject to the concentrate masses in the form of traffic loads, or the test equipments such as the accelerator in addition to their own masses. Analysis of such problems is usually very difficult. Most of the bridge slabs on girders have large aspect ratios. Finite difference method is used for this purpose, in this paper. The reuslt is compared with that of the beam theory.

      • 미세가공기술을 이용한 Interdigitated Array 전극의 제작 및 응용

        이강신,김태한,김승렬,신민철,이원용,박제균 경북대학교 센서기술연구소 1998 센서技術學術大會論文集 Vol.9 No.1

        Interdigitated array (IDA) electrodes were fabricated using silicon technology for highly sensitive biosensing. Thin-film platinum and gold IDA electrodes were fabricated with 10 μm band width and 7 μm gap between the bands using photolithographic techniques. The IDA electrode has 100 fingers consisting of 50 finger anodes and 50 finger cathodes. By applying both the oxidation and the reduction potentials of a reversible redox couple, ferrocyanide, to the pairs of the IDA electrode, an increased current generation can be observed. In our experiment, the collection efficiency of IDA electrode was 46% and amplification factor was 12.6. This preliminary experiment implies that the IDA electrode could be applied to biosensor fabrications as the sensitive electrochemical transducer when a lower detection limit is needed such as phenol sensor for drinking water analysis.

      • SCOPUSKCI등재
      • 논에 있어서 포장정보 공간변이의 공간통계학적 해석

        이충근,손연규,성제훈,정인규,김상철,박우풍,박원규 한국국제농업개발학회 2002 韓國國際農業開發學會誌 Vol.14 No.2

        논에 있어서 정밀농업을 위한 기초자료수집과 분석을 하기 위해서 토양의 특성, 포장면 고저차, 생육상태 그리고 수량에 관한 포장정보를 조사한 결과 아래와 같은 결과를 얻었다. 가. 기본통계값을 살펴보면 유효태 규산의 경우는 한 포장내 14배 이상의 변이차이를 보였으며, 생육정보 중 분얼수는 3배, 수량은 4배 이상의 차이를 보였다. 나. 포장정보의 변이계수를 살펴보면 5.45∼51.3%의 공간변이를 보였다. 토양특성 중에 pH를 제외한 나머지가 10%이상의 공간변이를 보였다. 포장면 고저차는 51.3%, 생육정보는 7.32∼23.2%, 그리고 수량에 있어서도 변이계수가 22.5%를 보였다. 다. 포장정보를 공간통계학을 이용해 해석한 결과, 포장정보의 공간구조 발달여부를 표시하는 Q값이 0.24∼1로서 공간구조가 포장정보에 따라서 발달되어 있었으며, 공간변이의 의존거리를 나타내는 랜지는 8.1∼147.9m를 보였다. 그러나, 실질적인 랜지는 토양특성값이 15∼50m 정도, 생육정보는 15m 전후, 포장면 고저차는 30m 정도, 수량은 8.1m를 보였다. 이것을 기초로 하여 크리깅 방법으로 데이터를 보간하여 지도화 시킨결과, 공간변이를 이해하는데 유용하게 이용될 수 있는 포장정보 지도를 얻을 수 있었다. Soil properties, relief of field surface, growth information, grain yield were investigated in a 1ha paddy field in 2001 to obtain basic field information for precision agriculture. The field information were analyzed to examine their within field variability using descriptive statistical method. Semivariograms and Kriged maps of geostatistical analysis were also adopted to examine their within field spatial dependence. The results obtained were as follows ; 1) Nutrient distribution difference of available SiO_2 was seemed 14 times overs, 3 times overs at tiller number, 4 times overs at grain yield from within a paddy field. 2) Descriptive statistics of field information showed that the coefficient of variation ranged from 5.45∼51.3%. 3) Field information showed a high spatial dependence within a paddy field. The Q values ranged from 0.24∼1, the ranges of spatial dependence were from 8.1∼50m, respectively. 4) Kriged maps enable the visualization and comparison of the spatial variability of field informaton.

      • 우심방과 우심실의 거대 심장 혈관종 1예

        김제열,조상호,김건일,허경림,김현숙,조구영,최영진,이원용,임종윤 朝鮮大學校 附設 醫學硏究所 2007 The Medical Journal of Chosun University Vol.32 No.2

        Cardiac tumors, especially the primary tumors involving any part of the heart are extremely rare and its relative incidence has been reported to be approximately 0.02%. We report a patient with huge cardiac hemangioma who complained of shortness of breath, general weakness, and dizziness, Imaging study by echocardiography and computed tomography of thorax revealed a huge lobulating mass like a bunch of grapes in the right chamber of heart. The surgical exploration of thorax was performed and a histological diagnosis of spindle cell hemangioma was obtained by microscopy. The patient was treated by surgical resection of the tumor and doing well after surgery. Our experience indicated that prompt diagnosis and treatment of cardiac hemangioma is imperative for patients' prognosis.

      • KCI등재

        鹿茸藥鍼液의 DNA chip을 利用한 遺傳子 發顯 分析

        한상원,서정철,이윤호,최제용 大韓鍼灸學會 2003 대한침구의학회지 Vol.20 No.3

        Objective : Bone homeostasis is maintained by balance of bone formation and resorption. Therefore, bone related diseases arose by disturbance of this balance between osteoblast and osteoclast activities. To develop a successful screening system the therapeutic components based on oriental medicine is essential to set up systematic approach for that purpose. The purpose of this study is to the know the gene expression using cDNA microarray assay. Methods : Cervi Pantotricuhum Cornu Herbal-acupuncture extract was prepared by boiling. human osteosarcoma cells(HOS) were treated with Cervi Pantotricuhum Cornu Herbal-acupuncture solution. Then mRNA was extracted and cDNA microarray assay was performed. Results : Human osteosarcoma cells(HOS) treated with Cervi Pantotricuhum Cornu Herbal-acupuncture solution(500㎍/㎖) showed that thioredoxin, TAFII31 and two novel genes were increased. However many genes decreased their expression by Cervi Pantotricuhum Cornu Herbal-acupuncture. Conclusions : This type of approach will give a good chance to explore the favorable effects of Cervi Pantotricuhum Cornu Herbal-acupuncture. Futher study is needed for investigating the effect of Cervi Pantotricuhum Cornu Herbal-acupuncture.

      • 시멘트 콘크리트의 건조수축균열 특성

        박제선,윤경구,이주형,김태환,정원경 강원대학교 부설 석재복합신소재 제품연구센터 2000 석재연 논문집 Vol.5 No.-

        콘크리트는 본질적으로 인장강고와 휨강도가 약하며 취성적 성질을 나타내는 결점을 가지고 있으므로 이를 보강할 목적으로 콘크리트에 섬유를 혼입한 섬유보강 콘크리트가 크게 각광받고 있다. 특히 폴리프로필렌 섬유보강은 모르타르 및 콘크리트가 건조나 동해에 의해 수축될 때 구속에 의해 발생되는 인장응력 및 균열을 제어하고 인성의 증가와 충격, 마모, 피로에 대한 저항성, 내구성을 증대시키는 장점을 가지는 것으로 보고 되고 있다. 1축으로 구속된 건조수축의 구속으로 인한 조강형 콘크리트의 잔류응력을 선형모델을 이용하여 예측할 수 있었고 조강형 콘크리트에 섬유보강으로 인한 건조수축 제어효과는 일반큰코리트에 비해 효과가 매우 큰 것으로 나타났다. 따라서 폴리크로필렌 섬유의 혼입으로 인해 콘크리트의 균열제어가 가능하며, 균열 폭이 큰 균열보다는 많은 미세 균열을 유도하는 것을 알 수 있었다. 섬유보강 조강형 큰크리트의 동결융해저항특성은 거의 동해의 손상을 받지 않으며 좋은 내구성을 유지하고 있는 것으로 나타났다. 이는 불규칙하게 배향된 섬유가 공극수의 이동을 효과적으로 제어함으로써 메트릭스 내의 팽창압으로 인한 파괴를 최대한 줄였기 때문이라고 보여진다. 표면손상과 박리저항에 매우 우수하며 저항성을 증진시키는 효과가 뛰어남을 확인할 수 있었다. 따라서, 내구적 측면의 유지, 보수에 있어서도 섬유보강은 그 효과가 큰 것으로 나타났다. To improve the brittle nature of concrete, discrete fibers can be adapted in concrete. Since polypropylene fiber has many advantages in many points on its chemical stability and good durability, its usages have been increased gradually. It has been reported than polypropylene fibers can not only control restrained tensional stresses and cracks, but also increase toughness, resistance to impact, corrosion, fatigue, and durability. Although the polypropylene fiber reinforced concretes with ordinary cement have been studied so much, those with very early strength concretes have not studied at all. Therefore, it is necessary to initiate and conduct the researches for the polypropylene fiber reinforced very early strength concretes which has enough workability and durability. This study of polypropylene fiber reinforced very early strength concrete focused on the investigation each material's effect into strength development with analysis of restrained shrinkage properties with one-dimensional concrete members. The results showed that more optimized mixture combinations could be selected in very early strength concrete by incorporating polypropylene fibers, keeping in same strength levels at urgent repair works. The formation of needle-shape ettringite helps the early strength development, specially at flexural and this enables the repaired concrete structures or pavements to be opened to traffic after 3 hours of concrete placement. A residual stress of early strength concrete caused by one-dimensional restrained drying shrinkage was predicted from linear model. the control of shrinkage crack by fiber reinforcement at early strength concrete was better than that of ordinary portland cement concrete because of bridging effect of fiber at early age and resulting of more hair cracks rather than fewer wider cracks. As a results, this dissertation clearly validated the fiber reinforcement on the strength development and durability of polypropylene fiber reinforced very early strength concrete, and characteristic of restrained shrinkage. The proposed optimized concrete mixtures might be satisfactory applied at the repair works in fields, because of its durability and crack control capacity against freeze-thaw and contraction at early age, respectively.

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