• 대한약리학회지
• /
• 제11권1호
• /
• pp.7-13
• /
• 1975

In Chinese medicine, it is said that Aconiti tuber has cardiotonic, diuretic and analgesic effects. Kim et al reported that alkaloid free part of Aconiti tuber, $CHCI_3$ insoluble fraction, showed inotropic effect on isolated frog heart and inotropic effect is potenciated by n-butanol fractionation. To investigate the effect of Aconiti tuber butanol fraction on the mechanical and electrical properties of heart, change of active tension, excitability and refractory period of isolated rabbit atrium in the presence of butanol fraction were measured and the comparison with that of ouabain and quinidine was done. The observed results are as follows. 1. $5{\times}10^{-4}g/ml$ concentration of Aconiti tuber butanol fraction showed approximately same effect with therapeutic concentration of ouabain on the increment of contractile force, and the effect of $2{\times}10^{-3}g/ml$ was greater than that of $1{\times}10^{-5}g/ml$ of ouabain. 2. Acceleration of rate of contractile force increment in the presence of Aconiti tuber butanol fraction was greater than in ouabain, and the time to maximum tension was shorter in Aconiti tuber butanol fraction than in ouabain. 3. The excitability of isolated atrium was slightly increased at low concentration of Aconiti tuber butanol fraction, while decreased at higher concentration. 4. Aconiti tuber butanol fraction slightly prolonged refractory period of isolated right atrium at the concentration of $2{\times}10^{-3}g/ml$.

• 순환기질환의공학회:학술대회논문집
• /
• 순환기질환의공학회 2002년도 제2회 학술대회 초록집
• /
• pp.46-47
• /
• 2002

• 한국태양에너지학회:학술대회논문집
• /
• 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
• /
• pp.217-222
• /
• 2011

This study examined the cooling performance of a solar heating and cooling system for an office building using the dynamic simulation program (TRNSYS). This solar heating and cooling system incorporates evacuated tube solar collectors of $204m^2$, storage tank of $8m^3$, 116.2kW auxiliary heater, single-effect $LiBr/H_2O$ absorption chiller of 20RT nominal cooling capacity. It was found that for the representing day showed peak cooling load the annual average collection efficiency of the collector was 32.9% and coefficient of performance of single-effect $LiBr/H_2O$ absorption chiller was 0.68. And the results shows for the cooling season the solar fraction of the solar heating and cooling system was 32.2% and maximal and minimal solar fraction was 63.4% for May 17.9% for July respectively.

• 한국식품과학회지
• /
• 제41권1호
• /
• pp.87-92
• /
• 2009

본 연구에서는 금불초(Inula britannica) 추출물의 항산화 효과와 ${H_2}{O_2}$로부터 유도된 SH-SY5Y 신경모세포종의 세포독성에 대한 보호능을 측정하였다. 금불초 지상부위의 70% 메탄올 추출물에 대하여 용매별로 분획을 실시하였고 핵산(Fr.H), 에틸아세테이트(Fr.EA) 및 물(Fr.W) 분획에 대하여 활성을 조사하였다. 분획 중 Fr.W의 폴리페놀/플라보노이드 함량이 가장 높았으며 Fr.W의 총 폴리페놀 함량은 $318.1{\pm}20.6{\mu}g$/mg solid로, Fr.EA 및 Fr.H와 비교하여 각각 약 2.5배, 23.1배 수준이었다. DPPH radical, ABTS radical 및 nitric oxide 소거능 등의 항산화 활성에서도 Fr.W가 가장 높은 활성을 나타내었고 Fr.H는 거의 활성을 나타내지 않았다. Fr.W는 ${H_2}{O_2}$에 의해 유도된 세포사멸에 대하여 62.5 ${\mu}g$/mL 농도에서 현저하게 세포독성을 감소시켰으며 250 ${\mu}g$/mL에서는 77.0%의 세포사멸 억제능을 보였다. Fr.EA는 보호 효과를 나타 내지 않았으며 Fr.H는 오히려 ${H_2}{O_2}$로 인한 세포 독성을 증가시키는 것으로 나타났다. 세포 내 ROS에 대한 영향으로 Fr.W 250 ${\mu}g$/mL 처리시 39.2% 세포내 ROS를 감소시켰으며 Fr.EA는 25 ${\mu}g$/mL에서 26.8%의 세포내 ROS를 소거하였다. 이러한 금불초 Fr.W의 항산화 활성은 ROS에 의해 야기되는 뇌세포 독성에 대한 보호 작용에 공헌할 수 있을 것으로 예상된다.

• 대한약리학회지
• /
• 제29권1호
• /
• pp.121-130
• /
• 1993

흰쥐 말초 T림프구에 분열유발 물질인 PMA와 Con A를 투여하여 인산화되는 단백을 확인하고, PKC 억제제인 H-7, CaM kinase 억제제인 W-7을 전처치한 후의 인산화 변동과 시간 경과에 따른 인산화 변동을 관찰하였다. 그 결과 흰쥐 T림프구를 PMA로 자극하면 5개의 인산화 단백이 새로이 나타나고 7개 단백의 인산화가 증가 되었으며, Con A자극으로는 1개의 단백이 새로이 인산화 되고 7개 단백의 인산화가 증가되었다. PMA 및 Con A자극으로 인산화 되는 13개 단백은 kinase억제제 전처치에 의하여 3군으로 각각 구분되며, H-7 전처치로 24 kDa/pI 7.1, 24/7.2, 26/6.1, 74/6.2 단백의, W-7 전처치로 14 kDa/pI5.9, 28/6.8, 29/6.9, 28/7.0, 44/6.8, 58/6.2 단백의 인산화가 현저히 감소 되었으며, 18 kDa/p1 5.4, 25/7.3 및 54/5.2단백은 두 억제제에 의해 영향을 받지 않았다. 이들 인산화 단백은 대부분 세포의 soluble fraction에서 확인되며 자극후 반응 초기에 인산화 된 후 인산화가 감소하나, 침전물에서 관찰되는 소수의 인산화 단백은 지속적인 인산화를 보였다. 한편 Kinase 억제제 처리에 의하여 구분된 3군에 속하는 단백들의 시간에 따른 인산화 양상을 관찰한 결과 각 군에 따른 인산화 양상에 상호 연관성이 없었다. 이상의 실험결과로 보아 림프구 활성의 초기 단계에서 인산화 되는 단백에는 PKC, CaM kinase 및 다른 kinase에 의해 인산화 되는 3종류의 단백이 존재하며, 3종류의 kinase의 활성은 단계적인 활성이 아니라 독립적 또는 상호 협동적으로 작용하여 림프구 활성을 유발시키는 것으로 생각된다.

• 한국약용작물학회지
• /
• 제18권5호
• /
• pp.323-328
• /
• 2010

Root extract of Lythrum salicaria reported a hepato-protective effect on $CCl_4$-induced liver toxicity of rat was prepared into fractions such as n-hexane up layer (HA), n-hexane down layer (HB), diethyl ether (E), ethylacetate (EA), n-butanol (B) and water (W). Fractions prepared were tested their activities in vitro and in vivo condition. All of the fractions showed effective antioxidant asctivities on DPPH radical and $CuSO_4$-induced oxidation of human low density lipoprotein and E fraction showed the highest inhibitory effect (98.1% at $50\;{\mu}g/m{\ell}$) on linoleic acid autoxidation at $40^{\circ}C$, which was more effective than $\alpha$-tocopherol (82.4%). Five fractions (H = HA plus HB, E, EA, B, and W, 150 mg/kg/day) were fed into Sprague Dawley, male rats for 4 days, which were intoxicated with intra-peritoneal injection of carbon tetrachloride ($1\;m{\ell}/kg$ in corn oil) at the 4th day and were sacrificed in 24 hrs. Serum tumor necrosis factor-alpha (TNF-$\alpha$), a proinflammatory cytokine, elevated with $CCl_4$-intoxication in negative control group ($83\;pg/m{\ell}$) was significantly decreased in E fraction-supplemented group ($18\;pg/m{\ell}$). Cu, Zn-superoxide dismutase (SOD) activity increased in negative control group (0.12 U/mg protein) was decreased in E fraction (0.07 U/mg protein). From the results, it is suggested that ether fraction from root extract of L. salicaria would be a potent antioxidant candidate for ameliorating liver injury induced by chemical intoxicant.

• 대한기계학회논문집B
• /
• 제22권6호
• /
• pp.888-898
• /
• 1998

The present study investigated the effects of the experimental parameters on the cooling characteristics of the multichip module cooled by the indirect liquid cooling method using water and paraffin slurry. The experimental parameters are mass fraction of 2.5 ~ 7.5% for paraffin slurry, heat flux of 10 ~ 40 W/cm$^{2}$ for the simulated VLSI chips and Reynolds numbers of 5,300 ~ 15,900. The apparatus consisted of test section, paraffin slurry maker, pump, constant temperature baths, flowmeter, etc. The test section made of in-line, four-row array of 12 heat sources for simulating 4 * 3 multichip module which was flush mounted on the top wall of a horizontal rectangular channel with the aspect ratio of 0.2. The inlet temperature was 20 deg. C for all experiments. The size of paraffin slurry was constant as 10 ~ 40 .mu.m befor and after the experiment. The chip surface temperatures for paraffin slurry with the mass fraction of 7.5% showed lower by 16 deg. C than those for water when the heat flux is 40 W/cm$^{2}$. The local heat transfer coefficients for the paraffin slurry with the mass fraction of 7.5% were larger by 17 ~ 25% than those for water at the first and the fourth row. The local heat transfer coefficients reached to a row-number-independent, thermally fully developed value approximately after the third row. The local Nusselt numbers at the fourth row for paraffin slurry with the mass fraction of 7.5% were larger by 23 ~ 29% than those for water.

• 한국균학회지
• /
• 제40권3호
• /
• pp.159-163
• /
• 2012

노루궁뎅이버섯을 이용하여 성인병 치료와 예방을 위한 기능성식품 개발을 위한 기초자료를 얻기 위해 노루궁뎅이버섯 물 추출물과 유기용매 분획물을 이용하여 성인병관련 생리활성을 확인하였다. 노루궁뎅이버섯 물 추출물은 87.78%의 항산화활성을 나타냈으며, 부탄올 분획물과물 분획물은 87.91%와 92.27%의 높은 활성을 나타냈다. 에틸 아세테이트 분획물은 2.96 plasmin unit의 높은 혈전용해 활성을 보였다. 핵산 분획물로부터 77.67%와 90.53%의 높은 트롬빈 저해활성과 ${\alpha}$-glucosidase 저해활성을 확인하였다. 실험 결과로부터 노루궁뎅이버섯 에틸아세테이트 분획물의 높은 혈전용해 활성과 핵산 분획물의 높은 트롬빈 저해활성과 ${\alpha}$-glucosidase 저해활성은 혈관계질환 치료나 예방을 위한 기능성식품 개발에 이용 가능할 것으로 기대된다.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2003년도 춘계학술대회논문집
• /
• pp.65-69
• /
• 2003

The effects of microstructural features on the fracture behaviors, including impact, high-cycle fatigue, fatigue and crack propagation, of thixoformed 357-T5 (Al-7%Si-0.6%Mg) alloy were examined. The resistance to impact and high-cycle fatigueof thixoformed 357-T5 tended to improve greatly with increasing solid volume fraction. An almost three-fold increase in impact energy value was, for example, observed with increasing solid volume fraction from 59 to 70%. The improvement in both impact and fatigue properties of thixoformed 357-75 with increasing solid volume fraction in the present study appeared to be related to the magnitude of stress concentration at the interface between primary and eutectic phase, by which the fracture process was largely influenced. Based on the fractographic and micrographic observations, the mechanism associated with the beneficial effect of high solid volume fraction in thixoformed 357-T5 alloy was discussed.

• 열처리공학회지
• /
• 제15권6호
• /
• pp.255-259
• /
• 2002

Effect of martensite on the mechanical properties of austempered ductile cast iron was investigated after obtained the martensite by subzero treatment. Retained austenite was transformed to martensite by subzero treatment, and with decreasing subzero treatment temperature, volume fraction of martensite was increased. With increasing of the volume fraction of martensite, tensile strength was increased and elongation was decreased, ratio of increasing of strength and decreasing of elongation was higher in case of specimens with lot's of Cu contents. With increasing of the volume fraction of martensite, hardness slowly increased until only about 5% and it rapidly increased in a straight proportion when it is above 5%, while impact value was rapidly decreased until about 7% but it had a little change when it is above 7%.