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        검색결과 200

        142.
        2008.05 구독 인증기관·개인회원 무료
        With the help of KLTER/ME and KLPS in Woraksan, we have surveyed monthly diversity and seasonal prevalence of Macrolepidoptera in Wol-ak-san [Mt.], Jecheon for the period of five months from May to September since 2005. In 2007, to reduce variation, we chose two monitoring points from each of three representative vegetations in the area: Quercus mongolica-, Quercus variabilis- and Pinus densiflora-formations, abbreviated as QM, QV and PD, respectively, and collected exclusively larger moths with bucket-type of light traps for quantified survey. As a result, 1) QM and QV showed the much higher species diversity than PD; 2) in number of individuals collected, QM was the highest, almost twice that of QV, and nearly 8 times that of PD; 3) in Noctuidae and Geometridae collected, QM was the highest, while in Pyralidae and Arctiidae collected, QV was the highest; 4) June was the highest in species diversity, then July was a deep drop, probably due to a storm occurred in July; 5) the number of individuals collected may not be a good indicator as one species may be dominant too much in number of individuals: e.g., Idaea biselata collected in QM in June was over 200, changing the average number of individuals per species to 6.92, which more than twice that of all other sites per month.
        143.
        2007.03 구독 인증기관 무료, 개인회원 유료
        The stem cell research is emerging as a cutting edge topic for a new treatment for many chronic diseases. Recently, dental stem cell would be possible for regeneration of tooth itself as well as periodontal tissue. However, the study of the cell characterization is scarce. Therefore, we performed the genetic profiling and the characterization of mouse fetus/neonate derived dental tissue and cell to find the identification during dental development. We separated dental arch from mandibles of 14.5 d fetal mice and neonate 0 d under the stereoscope, and isolated dental cells primarily from the tissues. Then, we examined morphology and the gene expression profiles of the primary cells and dental tissues from fetus/neonate and adult with RT-PCR. Primary dental cells showed heterogeneous but the majority was shown as fibroblast-like morphology. The change of population doubling time levels (PDLs) showed that the primary dental cells have growth potential and could be expanded under our culture conditions without reduction of growth rate. Immunocytochemical and flow cytometric analyses were performed to characterize the primary dental cell populations from both of fetus (E14.5) and neonate. Alpha smooth muscle actin (α-SMA), vimentin, and von Willebrand factor showed strong expression, but desmin positive cells were not detected in the primary dental cells. Most of the markers were not uniformly expressed, but found in subsets of cells, indicating that the primary dental cell population is heterogeneous, and characteristics of the populations were changed during culture period. And mesenchymal stem cell markers were highly expressed. Gene expression profile showed Wnt family and its related signaling molecules, growth factors, transcription factors and tooth specific molecules were expressed both fetal and neonatal tissue. The tooth specific genes (enamelin, amelogenin, and DSPP) only expressed in neonate and adult stage. These expression patterns appeared same as primary fetal and neonatal cells. In this study we isolated primary cells from whole mandible of fetal and neonatal mice. And we investigated the characteristics of the primary cells and the profile of gene expressions, which are involved in epithelial-mesenchymal interactions during tooth development. Taken together, the primary dental cells in early passages or fetal and neonatal mandibles could be useful stem cell resources.
        4,000원
        148.
        2020.06 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        The Korean Institute of Technology Satellite (KITSAT-1) is the first satellite developed by the Satellite Technology Research Center and the University of Surrey. KITSAT-1 is orbiting the Earth’s orbit as space debris with a 1,320 km altitude after the planned mission. Due to its relatively small size and altitude, tracking the KITSAT-1 was a difficult task. In this research, we analyzed the tracking results of KITSAT-1 for one year using the Midland Space Radar (MSR) in Texas and the Poker Flat Incoherent Scatter Radar (PFISR) in Alaska operated by LeoLabs, Inc. The tracking results were analyzed on a weekly basis for MSR and PFISR. The observation was conducted by using both stations at an average frequency of 10 times per week. The overall corrected range measurements for MSR and PFISR by LeoLabs were under 50 m and 25 m, respectively. The ionospheric delay, the dominant error source, was confirmed with the International Reference of Ionosphere-16 model and Global Navigation Satellite System data. The weekly basis orbit determination results were compared with two-line element data. The comparison results were used to confirm the orbital consistency of the estimated orbits.
        149.
        2019.03 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        The Optical Wide-field patroL-Network (OWL-Net) is a global optical network for Space Situational Awareness in Korea. The primary operational goal of the OWL-Net is to track Low Earth Orbit (LEO) satellites operated by Korea and to monitor the Geostationary Earth Orbit (GEO) region near the Korean peninsula. To obtain dense measurements on LEO tracking, the chopper system was adopted in the OWL-Net’s back-end system. Dozens of angle-only measurements can be obtained for a single shot with the observation mode for LEO tracking. In previous work, the reduction process of the LEO tracking data was presented, along with the mechanical specification of the back-end system of the OWL-Net. In this research, we describe an integrity assessment method of time-position matching and verification of results from real observations of LEO satellites. The change rate of the angle of each streak in the shot was checked to assess the results of the matching process. The time error due to the chopper rotation motion was corrected after re-matching of time and position. The corrected measurements were compared with the simulated observation data, which were taken from the Consolidated Prediction File from the International Laser Ranging Service. The comparison results are presented in the In-track and Cross-track frame.
        150.
        2018.04 KCI 등재 서비스 종료(열람 제한)
        혈관조영 및 중재적 방사선학 분야의 경우, 업무 특성상 눈의 방사선 피폭에 대한 위험성이 높다고 알려져 있으나, 현재 구분된 선량평가 및 관리가 이루어지지 않는 실정이다. 이에 본 연구에서는 시술 환경 내종사자의 눈에 대한 선량평가 및 차폐분석을 위해 첫 번째로, 시술자가 주로 위치하는 지점을 선정하고, 두 경부 팬텀 눈의 외안각 지점에 포켓선량계를 부착한 뒤 눈에 대한 피폭선량을 평가하였고, 현재 상용화된 납 안경 착용 시 차폐효과를 산정하였다. 두 번째로, 실측과 동일한 기하학적 구조 내 모의실험을 통해 눈의 피폭선량에 대한 경향성 평가와 차폐효과에 대해 분석하였다. 그 결과, 선량계를 이용한 측정의 경우, 방사선 투시촬영 시간이 증가함에 따라 누적선량이 증가하였고, 또한 시술자의 위치에 따라 각기 다른 양상을 보였다. 모의실험의 경우, 수학적 팬텀 내 눈의 수정체의 경우 각막보다 약 1.1 ~ 1.3배 높은 선량분포를 나타내는 것을 확인하였고, 납 안경의 방호효과는 눈의 각 기관별로 최소 3.7 ~ 최대 21.4% 차폐효과를 보였다.
        151.
        2017.11 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        본 연구에서는 까마귀쪽나무열매추출물(LJF-HE)의 흰 쥐모델에서 인도메타신으로 유발되어지는 위염에 대한 억제효과를 확인하고자 하였다. 까마귀쪽나무열매추출물 투 여그룹(LJF-HE-L, LJF-HE-M, LJF-HE-H)에서 염증길이와 위액량이 control 그룹에 비하여 통계적으로 유의하게 감소한 결과를 얻었다. 또한 위액량의 유의적인 감소효과로 위 산분비가 억제되어 공격인자 작용이 약해지는 원인과 펩신 의 활성도를 낮추는 원인으로 인하여 위염발생을 억제하는 것으로 판단되어진다. 까마귀쪽나무열매추출물(LJF-HE) 의 위산 분비 억제 기능은 gastrin 및 histamine에 의해 발현 되는 CCK-2r와 H2r 유전자의 발현을 억제하여, gastrin 및 histamine에 의한 위산 생성 단계를 조절하여, proton pump 인 H+/K+ ATPase 유전자 발현을 억제시키며, 그 결과로 인하여 위산 분비를 억제하는 것으로 판단되어진다. 그리고 까마귀쪽나무열매추출물은 점액을 증가시켜 위 점막을 보호하는 PGE2의 함량을 높여, 위 점막 보호 기능을 나타내고 있으며, 더불어 염증성 cytokine인 TNF-α와 IL-1β의 생성을 낮춰주어 염증 매개반응을 저해하는 것으로 판단되어 진다. 이와 같은 결과를 종합하면 까마귀쪽나무열매추출물 (LJF-HE)이 인도메타신으로 유발되어지는 위염에 대한 억제효과가 있는 것으로 판단되었다.
        152.
        2016.10 서비스 종료(열람 제한)
        Background : This study was conducted to serve as a basis for the production of high quality organic cultivation Platycodin grandiflorum Ridix roots by analyzing the content of saponins according to organic fertilizer for organic farming. Methods and Results : Platycodin grandiflorum Ridix was treated by with biodegradable film, rice husks, and sawdust, non-mulching (hand weeding). A root of Platycodon grandiflorum were analyzed saponins using HPLC harvested on October. Content of Plantycodin D3 was an average of 68.5 ㎎/100g, which appeared as 111.2 ㎎/100g highest content in the sawdust treated. Deapioplatycodin D showed the highest 48.1 ㎎/100g in the sawdust treated. The content of Platycodin D was shown to 246.2∼373.8 ㎎/100g, the highest values were observed in non-mulching, it showed the lowest value in the rice husks treated. The content of Polygalacin D showed up to 156.0 ㎎/100g in the non-mulching as the biggest difference, the lowest value were 30.1 and 32.2 ㎎/100g in sawdust and rice husks treated. Large differences between fertilizers was not showed, but the overall saponin content of Platycodin grandiflorum Ridix were low in value compared to the control than organic fertilizers. Conclusion : Large differences between mulching materials was showed, thus the overall saponin content of Platycodin grandiflorum Ridix was highest in value compared to non-mulching than sawdust treatment. Mulching Platycodin grandiflorum Ridix with sawdust was an effective method for improving saponin contents.
        153.
        2016.10 서비스 종료(열람 제한)
        Background : This study was performed to know the effect of mulching materials on the growth and root characteristics of Platycodin grandiflorum Ridix. Methods and Results : Platycodin grandiflorum Ridix was treated by with biodegradable film, rice husks, and sawdust, non-mulching (hand weeding). To measure the fresh weight and length, thickness and the number of fine root of the Platycodin grandiflorum Ridix roots harvested in October. Root length appeared in the biodegradable film and sawdust were 27.5 and 26.7㎝ longest, rice husks was the shortest 22.0㎝. Diameter at the thickest showed 30.9 ㎜ in biodegradable film, the following phrase appeared sawdust and rice husks application. The number of fine-root was investigated in biodegradable film most piece 36.0. Fresh weight, which is directly related to yield were biodegradable film to 130 g the highest in the number of fine-root and the longest root length. Conclusion : For the increasing the yield that Pharmacological effect, biodegrada
        154.
        2016.05 서비스 종료(열람 제한)
        Background : This study was conducted to serve as a basis for the production of high quality organic cultivation Platycodin grandiflorum Ridix roots by analyzing the content of saponins according to organic fertilizer for organic farming. Methods and Results : As basal fertilizer were treated before transplanting Platycodin grandiflorum Ridix with chemical fertilizer(Super21, 21-17-17, Namhae Chemical), mixed organic fertilizer, livestock manure, bacterial cultures and fermented oil cake in each trial of nitrogen based on 3 ㎏/10a criteria. A root of Platycodon grandiflorum were analyzed saponins using HPLC harvested on October. Content of Plantycodin D3 was an average of 40.6 ㎎ /100g, which appeared as 48.1 ㎎/100g highest content in the bacteria cultures treated. Deapioplatycodin D showed the highest 70.9 ㎎/100g in the control, the rest was investigated 28.1∼54 ㎎/100g. The content of Platycodin D was shown to 327.4∼373.8 ㎎/100g, the highest values were observed in mixed organic fertilizer, it showed the lowest value in the control. The content of Polygalacin D showed up to 336.7 ㎎/100g in the manure as the biggest difference, the lowest value were 54.5 and 74.2 ㎎/100g in bacterial cultures and control. Large differences between fertilizers was not showed, but the overall saponin content of Platycodin grandiflorum Ridix were low in value compared to the control than organic fertilizers. Conclusion : For the increasing the yield that Pharmacological effect, organic fertilizer is effective to increase the number of fine-root high which high contented with saponins.
        155.
        2016.05 서비스 종료(열람 제한)
        Background : This study was performed to know the effect of organic fertilizers on the growth and root characteristics of Platycodin grandiflorum Ridix. Methods and Results : As basal fertilizer were treated before transplanting Platycodin grandiflorum Ridix with chemical fertilizer(Super21, 21-17-17, Namhae Chemical), mixed organic fertilizer, bacterial cultures and fermented oil cake, manure in each trial of nitrogen based on 3 ㎏/10a criteria. To measure the fresh weight and length, thickness and the number of fine root of the Platycodin grandiflorum Ridix roots harvested in October. Root length appeared in the mixed organic fertilizer and chemical fertilizer were 25.3 and 24.0 ㎝ longest, oil cake was the shortest 15.3㎝. Diameter at the thickest showed 26.6 ㎜ in chemical fertilizer, the following phrase appeared bacterial cultures and mixed organic fertilizer application. The number of fine-root was investigated in mixed organic fertilizer and chemical fertilizer most pieces 20.0 and 17.0. Fresh weight, which is directly related to yield were mixed organic fertilizer to 55.7 g the highest in the number of fine-root and the longest root length. Conclusion : For the increasing the yield that Pharmacological effect, organic fertilizer is effective to increase the number of fine-root high which high contented with saponins.
        156.
        2015.12 서비스 종료(열람 제한)
        Rectal melanoma is extremely rare. Its histologic variability and difference in immunohistochemical (IHC) expression may hinder the correct diagnosis. Seventy-three years old Korean woman complained of bloody stool and found a 2cm sized rectal pedunculated polyp on colonoscopy. There was some disparity in IHC expressions as well as cytological morphology between biopsy and surgically resected specimen. When strong immunoreactivity of S-100 is encountered in anorectal lesion with unusual morphology, multiple IHC analysis and high suspicion of anorectal melanoma could lead to correct diagnosis.
        157.
        2015.09 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        A strategy is needed for a regional survey of geosynchronous orbits (GSOs) to monitor known space objects and detect uncataloged space objects. On the basis of the Inter-Agency Debris Committee’s recommendation regarding the protected region of geosynchronous Earth orbit (GEO), target satellites with perigee and apogee of GEO ± 200 km and various inclinations are selected for analysis. The status of the GSO region was analyzed using the satellite distribution based on the orbital characteristics in publicly available two-line element data. Natural perturbation effects cause inactive satellites to drift to two stable longitudinal points. Active satellites usually maintain the designed positions as a result of regular or irregular maneuver operations against their natural drift. To analyze the detection rate of a single optical telescope, 152 out of 412 active satellites and 135 out of 288 inactive satellites in the GSO region were selected on the basis of their visibility at the observation site in Daejeon, Korea. By using various vertical view ranges and various numbers of observations of the GSO region, the detection efficiencies were analyzed for a single night, and the numbers of follow-up observations were determined. The orbital estimation accuracies were also checked using the arc length and number of observed data points to maintain the GSO satellite catalog.
        158.
        2015.07 서비스 종료(열람 제한)
        It is necessary to carry out a risk assessment to determine the consequences of releasing a particular plant species containing specific transgenes before transgenic plants can be grown under filed conditions. Gene flow from transgenic plants to wild closely related species has raised concern recently. Since transgenic crops were released in 1996, the global area of transgenic crops has been increasing rapidly. The transgene introgression from transgenic crops to their wild relatives is unavoidable in some species. Transgene introgression is of concern because the crop–wild plant hybrids might be conferred with a selection advantage to increase their performance, which could result in negative ecological consequences to natural ecosystems. The genus Brassica has 159 species, including a number of wild species that are of great importance to the economy. Most transgenic Brassica gene flow research has focused on the most successful cross between transgenic oilseed rape Brassica napus and its wild relatives Brassica rapa, a widely distributed weed in the farming system in Europe and America, since the hybridization can spontaneously happen and the generations can backcross to B. rapa easily in the wild conditions. In this study, we aimed to characterize transgene introgression, segregation, and expression in backcrossed generations between tramsgenic B. napus and B. rapa. These results will contribute to the environmental risk assessment and assist in biosafety management.
        159.
        2015.07 서비스 종료(열람 제한)
        Cysteine protease (CP) is one of the well-studied proteolytic enzymes in plants. This class of protease has been implicated in various physiological aspects of developmental stages in plants including seed germination, senescence, and disease immunity. A handful of studies assigned plants cysteine protease in different molecular battlefield under a few selected pathosystems, and initially extricated complex molecular mechanism of resistance. However, its potential use as an agent of resistance to diseases in rice has never been explored. This study demonstrates the function of CP specifically in rice - Xanthomonas oryzae pv. oryzae (Xoo) pathosystem. The CP -encoding full-length cDNA was cloned from Brassica rapa and transformed into japonica rice cv. ‘Gopumbyeo’. The gene was overexpressed under the control of CaMV35S promoter in pFLC vector. Blast analysis of the conserved domain of the gene confirmed its affinity to Peptidase_CIA family. RT-PCR analysis showed that the gene was constitutively expressed in all tissues tested. Regulation of rice resistance through cysteine protease activity is evident in overexpression lines which exhibited an enhanced resistance to four Korean Xoo isolates. Further analyses will be carried out to uncover the specific role of CP in rice-Xoo interaction.
        160.
        2015.07 서비스 종료(열람 제한)
        Since global climate changes drastically, pre-harvest sprouting (PHS) is expected to pose serious problems in rice production. CBL-interacting serine/threonine protein kinases (CIPKs) have been implicated to play important role in regulating various abiotic stresses such as cold, salinity and drought. In this study, to understand the function of this gene under pre-harvest sprouting in rice, a cDNA clone encoding CBL-interacting protein kinase 15 was isolated from rice flowers. We constructed a recombinant vector carrying the CIPK15 under the control of the CaMV 35S promoter and Tnos terminator and transformed into rice using Agrobacterium tumefaciens. Insertion of the gene was verified in transformants using HPT resistance test and genomic PCR. Transcriptional profiling using tissues of wild type, Gopum, revealed expression of the gene in whole plant tissues with level of expression highest in the seeds suggesting possible role in dormancy. Comparative expression analysis of the gene in transgenic and wild type through semi-quantitative RT-PCR and real-time PCR showed higher expression in transgenic rice lines. Moreover, screening in the mist chamber showed overexpression lines that were resistant to the PHS. This result suggests the involvement of CIPK15 in the regulation of pre-harvest sprouting.
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