검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 19

        3.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Porcine spermatogonial stem cells (SSCs) prefer three-dimensional (3D) culture systems to 2D ones for the maintenance of self-renewal. Of the many 3D culture systems, agar-based hydrogels are candidates for supporting porcine SSC self-renewal, and there are various types of agar powder that can be used. In this study, we sought to identify an agar-based 3D hydrogel system that exhibited strong efficacy in the maintenance of porcine SSC self-renewal. First, 3D hydrogels with different mechanics were prepared with various concentrations of Bacto agar, lysogeny broth (LB) agar, and agarose powder, and the 3D hydrogel with the strongest alkaline phosphatase (AP) activity and greatest increase in colony size was identified for the different types of agar powder. Second, among the porcine SSCs cultured in the different 3D hydrogels, we analyzed the colony formation, morphology, and size; AP activity; and transcription and translation of porcine SSC-related genes, and these were compared to determine the optimal 3D hydrogel system for the maintenance of porcine SSC self-renewal. We found that 0.6% (w/v) Bacto agar-, 1% (w/v) LB agar-, and 0.2% (w/v) agarose-based 3D hydrogels showed the strongest maintenance of AP activity and the most pronounced increase in colony size in the culture of porcine SSCs. Moreover, among these hydrogels, the strongest transcription and translation of porcine SSC-related genes and largest colony size were detected in porcine SSCs cultured in the 0.2% (w/v) agarose-based 3D hydrogel, whereas there were no significant differences in colony formation and morphology. These results demonstrate that the 0.2% (w/v) agarose-based 3D hydrogel can be effectively used for the maintenance of porcine SSC self-renewal.
        4,000원
        4.
        2014.06 구독 인증기관 무료, 개인회원 유료
        Despite many researches related with in-vitro culture of porcine spematogonial stem cells (SSCs), adherent culture system widely used has shown a limitation in the maintenance of porcine SSC self-renewal. Therefore, in order to overcome this obstacle, suspension culture, which is known to have numerous advantage over adherent culture, was applied to the culture of porcine SSCs. Porcine SSCs retrieved from neonatal testes were suspension-cultured for 5 days or 20 days, and characteristics of suspension-cultured porcine SSCs including proliferation, alkaline phosphatase (AP) activity, and self-renewal-specific gene expression were investigated and compared with those of adherent-cul-tured porcine SSCs. As the results, the suspension-cultured porcine SSCs showed entirely non-proliferative and significantly higher rate of AP-positive cells and expression of self-renewal-specific genes than the adherent-cultured porcine SSCs. In addition, long-term culture of porcine SSCs in suspension condition induced significant decrease in the yield of AP staining-positive cells on post-day 10 of culture. These results showed that suspension culture was inappropriate to culture porcine SSCs, because the culture of porcine SSCs in suspension condition didn’t stimulate proliferation and maintain AP activity of porcine SSCs, regardless of culture periods.
        4,000원
        5.
        2010.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study aims to reveal how EA affects BAX and NF-kB involved in cell deaths from global ischemia, and to do this, observes the changes of BAX and NF-kB caused by EA application after transient global ischemia. The experimental method is to give rise to global ischemia and apply EA to 27 SD rats with the particulars of being six-week-old, male, around-300 gram-weighing, and adapted to laboratory environment for more than a week, and divide them into three groups, that is, GV20 EA group(n=9), L14 EA group(n=9), no-treatment GI group(n=9), and then observe their changes of BAX and NF-kB at the time lapse of 6 hours, 9 hours and 12 hours after ischemia, using western blotting. The numerical decrease of BAX expression at the time lapse of 9 hours after EA application, though not statistically significant, was observed in GV20 EA group and L14 EA group, and the NF-kB expression appeared statistically significant decrease in GV20 EA group and L14 EA group, but the expression was higher in the group with EA application. Therefore, EA application at the early phase of global ischemia is considered to affect BAX and NF-kB and play a positive role in decreasing apoptosis and cell deaths by inflammation.
        4,000원
        6.
        2008.09 구독 인증기관 무료, 개인회원 유료
        수평 배향 액정 모드는 양의 유전율 이방성과 음의 유전융 이방성 액정을 사용한 프린지 필드 스위칭과 양의 유전율 이방성 액정을 사용한 인플래인 스위칭 모드가 대표적이다 . 이 대표적인 세 구동 방식의 화질 특성을 비교하기 위하여 각각의 최척화된 위상지연 값 조건하에서 밝기, 명암대비율과 색 특성을 조사하였다. 그 결과 양액정과 음액정을 사용한 프린지 필드 스위칭 모드가 밝기와 명암대비율 면에 있어서 인플래인 스위칭 모드보다 우수한 특성을 보인다. 또한 양액정을 사용한 프린지 필드 스위 칭 모드는 시야각 방향에서 적은 색 변이 특성을 보인다.
        4,000원
        7.
        2007.12 구독 인증기관 무료, 개인회원 유료
        Field sequential 액정 디스플레이(FSLCD)는 컬러필터를 사용하지 않아 높은 투과율 특성을 보이고 광 원으로 LED를 사용함으로써 색재현성이 매우 우수하다. 하지만 FSLCD(60Hz 구동)를 실현하기 위해서는 액정의 응답속도가 5ms이하로 고속응답 특성을 보여야 한다. 따라서 본 논문에서는 고속응답 ECB(electrically controlled birefringence) 셀의 최적 구조를 연구하여 5ms 이하의 응답시간을 얻었다. 그리고 ECB 모드에서 높은 구동전압과 시야각을 개선하기 위해 필름 보상을 연구하였다. 판상형 액정필름(discotic film)과 TAC(triacetyl cellulose) 필름의 위상차 값을 최적화함으로써 구동전압을 5V로 낮추고 상하좌우에서 160° 이상(CR>10:1)의 시야각을 실현하였다.
        4,000원
        8.
        2016.10 서비스 종료(열람 제한)
        Background : This study was carried out to survey the effect of IBA (indole-3-butric acid) concentration on root development characteristics in Viburnum dilatatum cuttings. Methods and Results : The cuttings were collected on July 28, 2016 from plants growing in Korea National Arboretum. Cuttings were treated with different IBA concentrations [0 (control), 10, 100, 1000, 2000 ㎎⋅L-¹] for 10 seconds. Rooting parameters (root number, the longest root length, root fresh weight, root dry weight, rooting percentage, and survival rate) were observed at 8 weeks after cuttings. Rooting percentage was 43, 33, 17, 47, and 40 % at 0, 10, 100, 1000, and 2000 ㎎⋅L-¹ of IBA, respectively. Root number (13.4) was highest under 1000 ㎎⋅L-¹ IBA. Root length (9.4 ㎝) and Root weight (fresh and dry) were highest under 1000 ㎎⋅L-¹ IBA. Conclusion : According to the results, 1000 ㎎⋅L-¹ IBA was the best treatment for increasing percentage rooting percentage and other root development characteristics of V. dilatatum cuttings.
        9.
        2016.10 서비스 종료(열람 제한)
        Background : ROS produced by oxidative stress damaged endothelial cells, and cause a variety of vascular complications. In diabetic hyperglycemia state, ROS increase. The polyol pathway occur in diabetic complications, the excess glucose is absorbed into the polyol pathway when aldose reductase increased, NADPH changes it to sorbitol. Glutathione (GSH) removes ROS. GSH level is reduced by glutathione reductase, using NADPH as an electron donor. Activation of the polyol pathway decrease NADPH, and GSH also reduced. As a result, ROS is increased. In diabetic hyperglycemia state, Glycolysis increases. Effects of increased glycolysis, protein kinase C (PKC) is increased. NAD(P)H oxidase, stimulated by PKC-dependent pathway, increases ROS in the cell. In this study, we measured the ROS scavenging activity of 5 natural products (Lycii fructus, Astragalus membranaceus, Cassia Tora, Polygonatum odoratum, Rubus Coreanus), to confirm the efficacy as diabetic antioxidants. Methods and Results : We extracted 5 natural product by distilled water and ethanol. DPPH radical scavenging activity was significantly higher in Lycii fructus, Rubus coreanus. ABTS radical scavenging activity was better Rubus coreanus, Lycii fructus, Cassia Tora. In addition to, Rubus coreanus, Cassia Tora, Lycii fructus was comparatively higher reducing power activity than other natural products. And total phenolic and flavonoid contents were much higher in Rubus coreanus compared with other extracts. Conclusion : These results suggest that Lycii fructus, Rubus coreanus can be applied as diabetic antioxidant that prevent vascular complications caused by ROS.
        10.
        2016.05 서비스 종료(열람 제한)
        Background : Clematis trichotoma is a deciduous climber belonging to the family Ranunculaceae. This study was carried out to survey the effect of shading levels on growth characteristics in Clematis trichotoma seedling. Methods and Results : Seeds were collected from plants growing in the Mt. Kariwang Jeongseon, Gangwon-do in October 2013, and they were sown to 96 cell plug tray filled with Peatmoss (TKS-2) soil at March, 2015. The experiment was performed with four different shading levels (0, 30, 60, 90%) at July, 2015. According to the experiment, plant height was the highest under 90% of shading. It was found that fresh weight and dry weight of clematis trichotoma were the highest under 90% of shading. The leaf number was the highest under 30% of shading. The leaf number decreased as the shading level increased. Root number and length were the highest under 90% of shading. Conclusion : According to the results, Clematis trichotoma seedling showed the highest growth under 90% shading.
        11.
        2016.05 서비스 종료(열람 제한)
        Background : Scrophularia koraiensis is a herbaceous perennials belonging to the family Scrophulariaceae. This study was carried out to survey the effect of soil types on growth characteristics in Scrophularia koraiensis seedling. Methods and Results : Seeds were collected from plants growing in the Mt. Kariwang Jeongseon, Gangwon-do in September 2014, and they were sown to 128 cell plug tray filled with Peatmoss (TKS-2) soil at March, 2015. The experiment was performed with four different soil types (Peatmoss, Peatmoss + Perlite, Peatmoss + Granite soil, Commercial soil). According to the experiment, stem diameter was the highest under commercial soil. The leaf width and length were the highest under commercial soil. Main root diameter and lengh were the highest under commercial soil. Conclusion : According to the results, Scrophularia koraiensis seedling showed the highest growth in commercial soil.
        12.
        2016.05 서비스 종료(열람 제한)
        Background : Scrophularia koraiensis is a herbaceous perennials belonging to the family Scrophulariaceae. This study was carried out to survey the effect of LED on root develop characteristics in Scrophularia koraiensis seedling. Methods and Results : Seeds were collected from plants growing in the Mt. Kariwang Jeongseon, Gangwon-do in September 2014, and they were sown to 128 cell plug tray filled with Peatmoss (TKS-2) soil at March, 2015. The experiment was performed with three different LED (Blue, Red, Blue + Red) at July, 2015. Morphological characteristics of root (total root length, root projet area, root surface area, root diameter and root volume) were analyzed with WinRHIZO software. Seedling root growth of scrophularia koraiensis was surveyed to be the highest at the Blue + Red LED in all measuring. Total root length was measured high in the order of Blue + Red, Red, Blue LED. Conclusion : According to the results, Scrophularia koraiensis seedling showed the highest root growth in Blue + Red LED.
        14.
        2007.09 KCI 등재 서비스 종료(열람 제한)
        The genetic diversity was evaluated using RAPD and ISSR among natural populations and Korean wheat cultivars (Triticum aestivum). Understanding the genetic diversity of putative parental and wild stocks would be useful in wheat breeding programs. Ninety three populations were evaluated with fifty RAPD and three ISSR primers. A total of 185 RAPD and ISSR polymorphism were produced. These markers were considered to estimate the genetic distance among accessions. The genetic similarity ranged from 0.41 to 0.86. The dendrogram were constructed by using the UPGMA clustering algorithm based on genetic similarity. The genetic diversity within and among accession was assessed through Principal Component Analysis (PCA) for statistics analysis. In cluster analysis, four groups were clustered and 17 accessions were not clustered. The PCA was corresponded well to the result. This study provides basic information about the genetic relationships for breeding purposes.
        16.
        2006.08 KCI 등재 서비스 종료(열람 제한)
        A new oat (Avena sativa L.) cultivar 'Darkhorse' was developed by Honam Agricultural Research Institute (HARI) m2005. It was released because ofits earlmess, high forage yield potential and adaptability for late summer sowing. It was devel-oped from the a
        17.
        2006.08 KCI 등재 서비스 종료(열람 제한)
        A new oat (Avena sativa L.) cultivar, "Highspeed" was developed by Honam Agricultural Research Institute (HARI) in2005. It was released because of its earliness, high forage yield potential, and good adaptability for late summer sowing. "High-speed" was s
        18.
        2006.04 KCI 등재 서비스 종료(열람 제한)
        A six-rowed naked barley cultivar, Donghanchal (Hordeum vulgare L.), with low-amylose, winter hardiness, viral disease resistance and good quality, was developed from the cross between the advanced line “Masangwamac/Kangbori*7” and Naehanssalbori in 1993.
        19.
        2003.04 KCI 등재 서비스 종료(열람 제한)
        A new six-rowed naked barley cultivar, “Saenul”, was developed from a double cross between the F1 of Yonezawamochi/Olbori and Dangomugi at National Honam Agricultural Experiment Station RDA in 2001. It has the traits of early maturity, cold resistance, re