• Korean Journal of Plant Tissue Culture
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• v.22 no.1
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• pp.47-51
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• 1995

This study was conducted to investigate the possibility of obtaining platelets via somatic embryogenesis as a means of in vivo mass propagation in Paeonia lactiflora Pall.. When cultured on MS medium with 0.5 mg/L 2, 4-D, filament explants formed calli. UPon transfer to basal medium the calli gave rise to somatic embryos at a frequency of 38%. Additional of 3g/L activated charcoal enhanced the frequency to 60%. Mature embryos preheated at 5$^{\circ}C$ for 2 weeks had 37% germination on medium with 0.3 mg/L GA$_3$. The germinated embryos developed to complete plantlet when cultured on medium with 2mg/L BA.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.2
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• pp.153-159
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• 2010

Nowadays, Korean farmers rely more on chemical fertilizers than low input sustainable agriculture drawn from the farm itself. In order to improve soil nutritional imbalance for environment friendly agriculture in greenhouse, we have carried out a relationship between fertilizer application level, and soil chemical properties for strawberry cultivation at 56 sites in Chungnam Province. Average amount of nitrogen as basal fertilization was 92.3 Mg $ha^{-1}$ which higher 2.6 times compared to standard amount of basal fertilizer. In case of compost application more than 30 Mg $ha^{-1}$, excessive ratio compared to optimum level was higher 1.8 times for EC value, 3.0 times for available phosphate, 2.6 times for exchangeable potassium, 1.7 times for exchangeable calcium, and 1.6 times for exchangeable magnesium, respectively. Amounts of compost application significantly correlated with available phosphate (r=0.370, $p{\leq}0.01$), exchangeable potassium(r=0.429, $p{\leq}0.01$), exchangeable calcium(r=0.404, $p{\leq}0.01$), exchangeable magnesium(r=0.453, $p{\leq}0.01$), and exchangeable sodium(r=0.369, $p{\leq}0.01$), respectively. Our results suggest that soil nutrients management for sustainable agriculture was optimum fertilization based on soil testing for strawberry cultivation in greenhouse.

• Horticultural Science & Technology
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• v.31 no.3
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• pp.352-358
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• 2013

For the germination and differentiation of immature embryos obtained by artificial crossing between tetraploid grape 'Fujiminori' (Vitis vinifera ${\times}$ V. labruscana) and triploid 'Summer Black' (V. labruscana ${\times}$ V. vinifera), were incubated in vitro using MS medium supplemented with $GA_3$ or coconut water (CW) at various concentrations. The percentage of embryo formation of 'Fujiminori' ${\times}$ 'Summer Black' was 64.3%. Embryo germination percentage was higher than 95% in all the $GA_3$ treatments at the concentrations of 0.01, 0.05, 0.25, and $1.25mg{\cdot}L^{-1}$. However, only 15.8-31.6% of the germinated embryos successfully developed into normal plantlets. At higher concentration of $GA_3$, the plantlets developed infirm hypocotyls with over elongated and less enlarged structure. Among the treatments of CW at the concentrations of 5, 10, 15, and 20% (v/v), 10% and 15% were more effective and plantlet achievement percentage were 68.4 and 66.7%, respectively. The addition of 10% CW was most effective to obtain plantlets with optimal shoot length, node and root numbers. 15% CW was suitable to obtain plantlets with longer roots. Accordingly, the embryo culture using the MS medium supplemented with 10-15% CW was observed to be more efficient for germinating and growing the immature embryos produced from artificial crossing between tetraploid grape 'Fujiminori' and triploid 'Summer Black'.

• Journal of Plant Biotechnology
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• v.40 no.3
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• pp.141-146
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• 2013

This study was conducted to examine suspended embryogenic cells growth with days of culture, effects of various kinds/concentrations of osmoticum for induction of somatic embryos (SEs), following somatic embryos germination or plantlet regeneration. The proliferation pattern of embryogenic cells in suspension culture is characterized by settled cells volume (SCV) increased with the duration of culture with marked the maxium of SCV (10.1 ml) in 18 days of culture, however the SCV of cells gradually decreased after that. In comparison of kinds/concentrations of osmoticum on somatic embryo induction, the highest induction number (352.3/g FW) of the SE was showed in 0.2 M sucrose, in addition, we also observed some effects with treatments of 0.2 M maltose (203.7) and 0.3 M maltose (193.7), respectively. However, no somatic embryos produced in treatments of 7.5% PEG plus 0.15 M sucrose or maltose. In comparison of germination efficiency of SEs which occurred from the treatments of various kinds/ concentrations of osmoticum, the highest induction frequency of cotyledon (25.2%) was obtained from SEs that produced 0.3 M maltose, however, the best occurrence rates of hypocotyl (39%), radicle (30.3%) and plantlet regeneration (3.5%) were observed from the 0.2 M sucrose treatment, respectively.

• Korean Journal of Medicinal Crop Science
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• v.3 no.1
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• pp.50-55
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• 1995

This study was conducted to determine the optimum conditions for induction and different somatic of somatic embryos as well as germination of encapsulated and stored somatic embryos. Somatic embryos was better formed in 1/2X MS medium than full - strength MS medium. 0.1 to 1.0mg/lBA and kinetin promoted shoot differentiation of somatic embryos. Higher concentration tend to inhibit differentiation. IAA affect positively both root and shoot growth. In vitro germination of somatic embryos encapsulated with 2% alginate matrix containing 1/2 MS nutrient medium and $AgNO_3$ 5mg/l was 86%. Storage of somatic embryos was effecive at $5^{\circ}C$ but the germination rate decreased with longer storage period. RAPD analyses with plants regenerated from the somatic embryos showed DNA polymorphism, indicating abolition of primer binding site by point mutation, deletion, or insertion of certain sequences.

• The Korean Journal of Pesticide Science
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• v.7 no.4
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• pp.264-270
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• 2003

To control effectively and safely Phytophthora root rot caused by Phytophthora capsici on tomato in hydroponic culture, tank-mixing method was considered with two pesticides, metalaxyl copper oxychloride 50% WP and dimethomorph dithianon 38% WP. Forty days after transplanting of tomato seedlings, 4 mL of sporangia of P. capsici (about 25 sporangi/mL) per plot was inoculated around tomato plant roots, and at 5 days after inoculation, the pesticides tank-mixed at three dilution levels, 12,500, 25,000 and 50,000, were drenched 1, 2 or 3 times per plot on the culture cube every 15 days for metalaxyl copper oxychloride 50% WP and every 10 days for dimethomorph dithianon 38% WP. During the drenching period, the residue levels of metalaxyl and dimethomorph in hydroponic culture solution were similar to the initial levels but the level of dithianon was drastically decreased from one day after tank-mixing. In tomato drenched with metalaxyl copper oxychloride 50% WP, metalaxyl was detected $0.02\sim0.04$ mg/kg in all diluted plots. Dimethomorph was detected $0.012\sim0.021$, $0.001\sim0.006$ and $0.001\sim0.003$ mg/kg in 12,500, 25,000 and 50,000 times diluted plots, respectively, while dithianon was detected 0.005, 0.003 mg/kg in 12,500 and 50,000 times diluted plots, respectively. The detection levels of three pesticides were far below compared with the levels of Korean MRLs. Incidences of Phytophthora root rot were not found in all the plots, but phytotoxic responses were recognized in the 12,500 times diluted plots of both pesticides. Based on the above results, the drenching of the culture solution tank-mixed with these pesticides could be recommended as a very safe and effective method to control Phytophthora root rot in tomato in hydroponic culture.

• Korean Journal of Plant Tissue Culture
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• v.22 no.5
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• pp.299-306
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• 1995

The objective of this study is to establish an efficient celll culture system for somatic embryogenesis in Ostericum koreanum and Angelica purpuraefolia. The highest frequency of embryogenic callus on immature seeds of O. konanum and A, purpuraefolia. was obtained when seeds were cultured on MS medium containing 0.1 mg/L 2,4-D and 0.1 mg/L BA. However somatic embryos were formed directly from the edge of cotyledon and hypocotyl of plant which regenerated on medium supplemented with 0.1-3.0 mg/L NAA. Immature seed explane cultured at 25$\pm$2$^{\circ}C$ after 10 days treatment at 5$^{\circ}C$ produced embryogenic callus and somatic embryos, and these differentiated into whole plane. Addition of glutamine and coconut milk to media did not enhance the frequency of somatic embryogenesis in immature seed cultures of A. purpuraefolia. However in immature seed culture of O. koreanum, the frequency of somatic embryogenesis were increased on media supplemented with glutamine and 10% coconut milk. Especially addition of glutamine to the medium substituted effect of NH$_4$N0$_3$ in constast to coconut milk. The highest frequency of conversion somatic embryos into plantlet was 89.1% on MS basal medium Embryogenic calli were grown vigorously when maintained on medium with 0.01 mg/L 2,4-D and 0.01 mg/L BA.

• Journal of agricultural medicine and community health
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• v.46 no.3
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• pp.171-185
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• 2021

배경: 2015년 한국의 중동호흡기증후군 유행에서 지역간 치명률의 차이는 극명하였다. 이 연구는 대전 클러스터와 다른 지역 간의 치명률의 관련된 일반적 특성 및 역학적 요인을 밝히고저 하였다. 방법: 입원병원 소재지를 기준으로 대전과 타 지역으로 구분하여 관련변수에 따른 카이제곱검정 및 피셔정확검정 등으로 분석하였다. 대전과 다른 지역의 치명률(CFR)의 차이와 관련된 요인을 분석하기 위하여 단변량 및 다변량 로지스틱 회귀분석를 실시하였다. 결과: 모형 I에서는 65세 이상 연령군일수록 7.12배(95% CI 2.33-21.8)(p=0.001), 동반질환이 있는 경우 10.29배(95% CI 2.94-36.06)(p<0.001), 잠복기가 7일 이하인 경우가 8.55배(95% CI 2.54-26.7), 입원기간이 17일 이하인 경우 10.08배(95% CI 2.99-31.9)(p<0.001) 등이었으며, 모형 II에서는 65세 이상 연령군일수록 5.34배(95% CI 1.65-17.2)(p=0.005), 잠복기가 7일 이하인 경우가 6.70배(95% CI 1.96-22.89), 입원기간이 17일 이하인 경우 8.90배(95% CI 2.59-30.6)(p=0.001), 동반질환에서 암의 경우에서 7.15배(95% CI 1.64-31.14)(p=0.009) 등이었다. 결론: 2015년 한국 중동호흡기증후군 유행에서 대전 클러스터의 높은 치명율은 연령(≥65세), 동반질환(특히 암), 잠복기(≤7일), 입원기간(≤17일) 등이 유의한 변수로 도출되었다.

• Journal of Life Science
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• v.20 no.11
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• pp.1711-1717
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• 2010

In this study, fibrinolytic activities of fermented yellow agabean (FYA) and black agabean (FBA), and the antioxidation efficiencies of 70% ethanol extract of fermented yellow agabean (FYAE) and black agabean (FBAE) were investigated by selecting Bacillus sp. sm26 strain. Fibrinolytic activities of FYA and FBA were $6.38{\pm}0.5$ and $6.83{\pm}0.5\;U/ml$, which were 1.3 and 1.4 times higher than that of FSB, respectively. With regard to total phenolic contents, FYAE and FBAE were $3.40{\pm}0.44\;mg/g$ and $2.45{\pm}0.20\;mg/g$ respectively, suggesting that their contents were about twice as high as that of fermented soybean extract (FSBE) used as a control. In comparison with FSBE, total protein and sugar contents of FYAE were $0.56{\pm}0.11$ and $2.41{\pm}0.48\;mg/g$, respectively, and those of FBAE were $0.39{\pm}0.12$ and $2.72{\pm}0.63\;mg/g$, respectively. This result suggests that FYAE was 4.7 and 1.7 times higher than FSBE, respectively. The DPPH radical scavenging activity of FBAE was 79% at 1 mg/ml, which was highest among the fermented bean extracts, and was twice as high as FSBE in regards to activity. In addition, FBAE exhibited the highest reducing power at 1 mg/ml, which was higher than FSBE by two-fold. With regard to lipid peroxidation, FBAE and FYAE were 93% and 80% at 1 mg/ml, which were 3 and 2.5 times higher than FSBE, respectively. Of note, the hydrogen peroxide scavenging activities of FBAE and FYAE were 82% and 54% at 1 mg/ml, offering activity that was 4 and 2.5 times higher than FSBE, respectively. Based on these results, the fibrinolytic activity and antioxidation efficiency of the fermented agabeans were significantly higher than other soybeans. Therefore, these studies may suggest that the functional agabeans can be a potential candidate for a natural functional food.

• Clinical and Experimental Reproductive Medicine
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• v.31 no.1
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• pp.1-7
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• 2004

연구 목적: 본 연구의 목적은 마우스에서 배양액의 용량이 배반포 배 형성과 세포수에 미치는 영향을 조사하기 위하여 실시하였다. 연구 재료 및 방법: $3{\sim}4$주령 ICR 암마우스에게 48시간 간격으로 5 IU PMSG와 hCG 주사 후 (hCG 주사 후 수컷과 동숙) $46{\sim}50$시간에 난관으로부터 총 138개의 2-세포기 배를 회수하여 2 ml (group I) 또는 $50{\mu}l$ (group II)의 배양액 (Dulbecco's Modified Eagle Medium + 20% human follicular fluid)에서 72시간 동안 배반포기까지 배양하였다. 배반포 배는 zona-intact (ZiB)와 zona-escape (ZeB)로 등급을 구분하고 나서, propidium iodide와 bisbenzimide를 이용한 differential staining 방법으로 염색하여 평균 세포수, 내세포괴(ICM) 세포수, 영양배엽(TE) 세포수, 총 세포수에 대한 ICM의 비율 (%ICM) 및 ICM:TE 비율을 조사하였다. 결과에 대한 유의성 검정은 $X^2$ test와 t-test를 이용하였으며, p<0.05일 때 통계적인 차이가 있는 것으로 하였다. 결 과: Group I과 II에서, 총 배반포 ($62.3{\pm}20.7%$ vs. $63.8{\pm}22.9%$), ZiB ($31.9{\pm}24.0%$ vs. $30.4{\pm}18.2%$)와 ZeB 형성율 ($30.4{\pm}20.8%$ vs. $33.3{\pm}22.3%$)은 차이가 없었다. 87개의 배반포 배를 염색 시도하였는데, 명확하게 differential staining된 41개의 배반포 배만을 대상으로 세포수를 조사하였다. 평균 세포수 ($61.6{\pm}19.5$ vs. $63.7{\pm}26.8$), ICM 세포수 ($13.0{\pm}10.6$ vs. $12.8{\pm}10.5$), TE 세포수 ($49.0{\pm}19.0$ vs. $47.8{\pm}18.7$), %ICM ($21.0{\pm}12.6%$ vs. $21.1{\pm}13.2%$) 및 ICM:TE 비율 (1:$3.77{\pm}4.9$ vs. 1:$3.72{\pm}4.8$)에서도 group I과 II에서 차이가 없었다. 결 론: 마우스에서 배 발생 능력의 척도로 쓰이는 배반포 배 형성율 배반포 배의 등급 세포수 및 %ICM 등이 20% 난포액을 첨가한 MEM 배양액의 용량에 따라 영향을 받지 않았다.