• Title/Summary/Keyword: 증식특성

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Characteristics of Crude Protein-bound Polysaccharide from Agaricus blasei Murill by Extraction and Precipitation Conditions and Its Antitumor Effect (추출 및 침전조건에 따른 아가리쿠스버섯에서 분리한 조단백다당류의 특성 및 암세포 증식억제 효과)

  • Hong, Joo-Heon;Youn, Kwang-Sup;Choi, Yong-Hee
    • Korean Journal of Food Science and Technology
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    • v.36 no.4
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    • pp.586-593
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    • 2004
  • Efficient extraction method of crude protein-bound polysaccharide (CPBP) from Agaricus blasei Murill was established. CPBP yields by ultrasonic and hot water extractions were 13.0 and 7.8%, respectively. Pressure extraction for 3 hr gave the highest ${\beta}-glucan$ content; no significant difference was observed between 2 and 3 hr extraction. Four volumes added ethanol gave the highest yields of CPBP and ${\beta}-glucan$ contents at 10.89 and 35.97%, respectively. Decomposition temperature of CPBP was $240-365^{\circ}C$, showing relatively good thermal stability. In SRB (sulforhodamine B) assay, CPBP treatment at $1,000\;{\mu}g/mL$ for 72 hr inhibited proliferations to A549, MCF-7, and AGS cancer cells by 43.9, 21.4, and 32.5%, respectively.

Market Imperfections as an Explanation for Higher Premiums in Foreign Takeovers of U.S. Companies (외국기업(外國企業)이 미국기업(美國企業)을 인수(引受)할 때 지불(支拂)하는 높은 프레미엄에 대한 설명(說明)으로서의 시장불완전성(市場不完全性))

  • Jung, Hyung-Chan
    • The Korean Journal of Financial Management
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    • v.8 no.2
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    • pp.209-255
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    • 1991
  • This paper develops a simple model to explain the reasons why foreign acquirers pay significantly higher premiums for U.S. target firms than do U.S. buyers. We also provide empirical work on the valuation effect of foreign takeovers and the determinants of the wealth gains of U.S. target shareholders involved in foreign takeovers. The results indicate that target wealth gains are significantly higher in foreign takeovers than in domestic takeovers, after controlling for the wealth effects of payment method, acquisition type, tax status, size and time period of bids. This confirms the valuation effect of foreign takeovers. Furthermore, the results of cross-sectional regression analysis show that the variation in U.S. target wealth gains is explained by extra tax benefits stemming from double tax deductions for acquisition-related interest expenses incurred by foreign acquirers. These findings imply that differential taxation across tax jurisdictions is the main source of the valuation effect of foreign takeovers. In addition, we find that there exists a valuation effect of the nationality of the foreign acquirers. Japanese companies pay significantly higher premiums than do non-Japanese acquirers. The finding also indicates that competition among bidders increases the abnormal returns to U.S. target shareholders in foreign takeovers.

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가막만 소호해역에서 태풍 전후 수질 변동특성

  • Lee, Yeong-Sik
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2007.05a
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    • pp.294-297
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    • 2007
  • 유기유기물 증가원인의 파악과 근본적인 대책에 대한 연구의 일환으로 부영양화된 연안해역에 대하여 태풍 발생 전후의 수질변동에 대하여 조사하였다. 그 결과를 요약하면 다음과 같다. 1) 용존산소 포화도는 수온과 염분 약층이 형성된 시기에 저층에서 54% 이하로 관측되었다. 태풍이 지나간 직후에는 표층과 저층에서 거의 비슷한 용존산소 포화도$(78{\sim}88%)$가 조사되었다. 그리고, 태풍이 지나간 3일 후 식물플랑크톤이 대량으로 증식한 표층에서 용존산소 포화도가 234%로 아주 높은 값이 관측되었고, 저층(5m)에서도 90%가 조사되어, 태풍과 식물플랑크톤의 이상 증식이 저층의 용존산소 포화도를 높이는 작용을 한 것으로 보인다. 2) 염분이 가장 낮았던 시기에 표층에서 $NA_4-N$, $NO_3-N$, $SiO_2-Si$의 농도가 각각 18.22, 38.90, 52.10uM로 아주 높게 조사되었으며, $NH4-N$, $PO_4-P$, $SiO_2-Si$는 용존산소가 낮은 저층에서도 높게 나타났다. 3) 클로로필은 최고 $311.0{\mu}g/L$가 태풍 후에 관측되었으며, 그 원인 생물은 Scrippsiella trochoidea (42,000cells/mL)였다. 조류성장잠재능력은 태풍발생 후에 아주 높게 조사되었으며, 항상 질소가 부족한 것으로 조사되었다. 4) 화학적 산소요구량은 최고 10.55 mg/L였으며, 태풍으로 저층 퇴적물로부터 부유되는 유기 오탁 물질이 화학적 산소요구량 증가에 미치는 기여도는 크지 않은 것으로 보이며, 화학적 산소요구량 증가의 대부분이 식물플랑크톤의 증식에 기인한 것($r^2=0.612$, p<0.0001)으로 조사되었다.

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Osteoblast Cell Morphology, Proliferation, and Differentiation in Variation with Biomaterials (생체재료의 선택에 따른 조골세포의 형상, 증식 및 분화)

  • 김학관;장주웅;정희석;이득용
    • Journal of the Korean Ceramic Society
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    • v.40 no.6
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    • pp.601-607
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    • 2003
  • Osteoblast-like cell morphology, proliferation, and differentiation were examined in variation with biomaterials. Cells were cultured on TiO$_2$, Ti, 3Y-TZP, HA (Hydroxyapatite) and Thermanox was used as a control specimen. Generally, all specimens have similar cell morphology within the same time interval. However, cells on HA seem to be more thicker than those on TiO$_2$, Ti, 3Y-TZP and cell overlapping was detected very frequently on HA. In case of cell proliferation and differentiation, bioactive material such as HA could help osteoblast-like cell proliferate and provoke a sharp increase of ALP. On the other hand, whether the substrate material is a bioinert ceramics or metal, it does not so strongly affect the cell attachment, proliferation. and differentiation.

Biological Activities of Oyster Mushroom Kimchi (느타리버섯 김치의 생리활성)

  • 서권일;한서영;박미숙
    • Food Science and Preservation
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    • v.9 no.1
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    • pp.56-60
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    • 2002
  • Physiological functions of oyster mushroom Kimchi were investigated. Oyster mushroom Kimhies were found to have antioxidant activities. The effect was in a dose-dependent manner, the effect was higher in oyster mushroom Kimchies than in control and higher in raw oyster mushroom Kimchi (ROMK) than in blanched oyster mushroom Kimchi (BOMK). Methanol extract of Kimchi revealed antimutagenic activity and suppressed growth of cancer cell in a dose-dependent manner, and the effects were higher in ROMK than in other Kimchies. The methanol extracts of oyster mushroom Kimchi alone did not appear proliferation effect of spleenic immune cell, but revealed the effect with Con A. The proliferation effect was higher in ROMK than in BOMK.

A potential anticacner therapeutic strategy using light-emitting diode (자궁경부암세포 치료를 위한 발광다이오드의 응용)

  • Park, Chul Woo;Park, Kitae;Choi, Hojong;Choe, Se-woon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2017.05a
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    • pp.712-713
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    • 2017
  • Clinically applicable light emitting diode (LED) has been widely investigated because of relatively low heat generation, low cytotoxicity, and non-invasiveness compared to other therapeutic methods. Therefore, we investigated the therapeutic effects of several wavelengths of light emitting diode against human cervical cancer cells and analyzed the individual inhibitory effect for the cancer cell proliferation. In the experiment, prepared HeLa cells were exposed by red, green and blue light-emitting diode for 10 minutes each. Relatively short-wavelength light-emitting diode (blue) showed stronger therapeutic effects than relatively long-wavelength light-emitting diodes.

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Zymomonas mobilis에 의해 생성된 Fructan (Levan)의 특성 및 화장품 원료로의 개발

  • 이재섭;양은경;이정하;김철호;박수남;이종원;김기호
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.28 no.1
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    • pp.186-201
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    • 2002
  • Fructan(Levan)은 식물체 및 미생물에서 발견되는 탄수화물로 이는 과당(fructose)이 $\beta$-2, 6 결합으로 연결되어 있는 polysaccaride 이다. 본 연구에서는 Fructan을 생성하는 미생물(Zymomonas mobilis)과 10% sucrose(기질), 1-2% 효모 추출물을 주성분으로 하는 배지를 사용하여 30-37$^{\circ}C$, pH 5.0-7.0에서 20-24시간 동안 배양한후 원심분리하여 균체를 제거하고 3배량의 알코올을 가하여 침전, 건조하여 얻은 Fructan의 화장품 원료로서의 가능성을 조사하였다. 보습효과에 있어서는 Hyaluronic acid와 유사하였으며, keratinocyte에 대한 세포증식 효과를 나타내었다. 또한 3-D culture에 의해 구축된 생인공 피부내에 0.05%의 sodium lauryl sulfate (SLS)를 사용하여 피부자극에 의한 초기 염증 반응을 유도한후 0.01mg/m1, 0.05mg/m1의 Fructan을 각각 처리하였을 때, SLS만을 처리한 생인공피부와 비교하여 세포증식효능을 보였고, SLS 자극물질로 유도된 전염증성 조절인자인 interleukin-l$\alpha$(IL-l$\alpha$)의 분비량을 조사 하였을때 0.01mg/ml, 0.05mg/ml의 Fructan을 처리한 생인공피부의 IL-l$\alpha$ 양이 Fructan을 처리하지 않은 것보다 상대적으로 감소하였다. 이러한 결과로 Fructan이 생인공 피부내 피부 세포의 증식효과를 나타낼 뿐만 아니라, 또한 피부자극물질에 의한 염증반응에 대해 자극완화효능이 있음을 알 수 있었다. 섬유아세포 및 동물을 이용한 안전성 시험에서도 독성이 없는 안전한 원료로 평가되었다.

불완전 결정성 아파타이트 박막의 특성 및 응용

  • Kim, Hyeon-Man
    • Ceramist
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    • v.3 no.3
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    • pp.58-70
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    • 2000
  • 뼈 결정과 같이 결정도가 낮은 탄산 인회석 결정의 화학조성 및 구조는 순수 수산화인회석 과 물리적 및 화학적 성질에 있어서 매우 다르다. 극미세 결정으로 결정도가 매우 낮은 불완전 결정이며, 결정 표면은 매우 반응성이 높은 이온으로 구성되어 있어 유기분자나 세포와 활발히 반응할 수 있다. 이와 같은 뼈 결정의 특성을 고형 기질 표면에 불완전 결정도 인회석 박막을 형성시켜 생체재료에 재현하였다. 이 박막에는 뼈세포들이 잘 부착하였는데 특히 골모세포의 부착, 증식, 분화를 촉진하여 장차 이와 같은 뼈 탄산 인회석의 특성을 갖는 인회석을 생체이식 재료로 이용하므로써 우리 몸의 생리에 좀 더 가까운 인공 매식체를 개발할 수 있을 것으로 기대된다.

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Efficiency of Nutritive Salts Removal and Algae Growth Inhibition Using a Fibrous Carrier (섬유상 담체를 이용한 영양염류 제거 및 조류 증식 억제에 관한 연구)

  • Park, Sin-Hae;Kang, Dae-Jong;Yang, Kyeong-Soon;Jeon, Soo-Bin;Oh, Kwang-Joong
    • Clean Technology
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    • v.21 no.4
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    • pp.257-264
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    • 2015
  • Conventional physicochemical technologies for algae growth inhibition have economical and environmental pollution problems. This study attempted to overcome the problems by nature-friendly biological inhibition technology using fibrous carrier. The experimental results showed that the most effective carrier material, polyester, exhibited the highest biofilm thickness. The removal efficiency for nutrient salts, such as nitrogen and phosphorous, and algae growth inhibition of polyester carrier was 14.59%, 6.36%, and 77%, respectively, which is higher than for control group. These result indicate that the polyester carrier is available in eutrophic lake.

Cellulase and Xylanase Activity of Compost-promoting Bacteria Bacillus sp. SJ21 (부숙촉진 세균 Bacillus sp. SJ21 균주의 cellulase와 xylanase 활성)

  • Shin, Pyung-Gyun;Cho, Soo-Jeong
    • Korean Journal of Soil Science and Fertilizer
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    • v.44 no.5
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    • pp.836-840
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    • 2011
  • In order to isolate thermophilic compost-promoting bacteria with high activity of cellulase and xylanase, spent mushroom substrates with sawdust were collected from mushroom cultivation farm, Jinju, Gyeongnam in Korea. Among of the isolates, one strain, designated SJ21 was selected by agar diffusion method. The strain SJ21 was identified as members of the Bacillus lincheniformis by biochemical characteristics using Bacillus ID kit and VITEK 2 system. Comparative 16S rDNA gene sequence analysis showed that strain SJ21 formed a distinct phylogenetic tree within the genus Bacillus and was most closely related to Bacillus subtilis with 16S rDNA gene sequence similarity of 99%. On the basis of its physiological properties, biochemical characteristics and phylogenetic distinctiveness, strain SJ21 was classified within the genus Bacillus, for which the name Bacillus sp. SJ21 is proposed. The cellulase and xylanase activity of Bacillus sp. SJ21 was slightly increased according to bacterial population from exponential phase to stationary phase in growth curve for Bacillus sp. SJ21.