• 아시안잔디학회지
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• 제10권2호
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• pp.167-175
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• 1996

This study was carried out to investigate the removal rate of sulphur of the litters in the Phragmites communsis, Seirpus tabernaemontani, Miscanthus sacchariflorus and Typha angustata aquatic grassland ecosystem on the lake Paldangho. The annual litter productions of sulphur were 50.91 /$m^2$, in P. communis, 180.83 g /$m^2$, in S. tabernaemontani, 25.87 g /$m^2$, in M. sacchariflorus and 151.39 g /$m^2$, in T. angustata, respectively. The removal rates r, of sulphur in the litters were 0.86 in P. communis, 0.82 in S. tabernaemontani, 0.43 in M. sacchariflorus and 0.47 in T. angustata respectively, The times required to reach 50, 95 and 99 percent of the steady state levels and turnover values of sulphur on the grass-land floor were 0.81, 3.49 and 5.82 years in the P. communis, 0.85, 3.68 and 6.13 years in the S. tabernaemontani, 1.62, 7.00 and 11.67 years in the M. sacchariflorus and 1.49, 6.44 and 10.73 years in the T. angustata, It is considered that the high removal rates of sulphur in four grasslands of aquatic ecosystem contribute to the efficient removal of sulphur, a pollutant, at the lake Paldangho. Key words: Removal rate, Accmulation, Paldaugho, Sulphur, Phragmites communis, Miscanthus saechariflorus, Seirpus tabernaemontani, Typha angastata.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1993년도 춘계학술발표회
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• pp.43-44
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• 1993

In this study SOI MOSFET model of the structure with 4-terminals and 3-interfaces is proposed. An SOI MOSFET is modeled with the equivalent circuit considered the interface capacitances. Parameters of SOI MOSFET device are extracted, and the electrical characteristics due to back-bias change is simulated. In SOI-MOSFET model device we describe the characteristics of threshold voltage, subthreshold slope, maxium electrical field and drain currents in the front channel when the back channel condition move into accmulation, depletion, and inversion regions respectively.

• 생약학회지
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• 제15권2호
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• pp.61-73
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• 1984

To investigate antitumor component of Lyophyllum decastes, the aqueous extract of its shake-cultured mycelia was subjected to antitumor test against sarcoma 180 cells implanted in ICR mice. The extract showed an inhibition ratio of 65.4% and was found to consist of a polysaccharide moiety and a protein moiety. After purification with DEAE-Sephadex A-50 ion exchange chromatography, Fraction D showed the highest inhibition ratio of 75.7%. The antitumor constituent was examined for immunoaccelerating activity and was found to increase macrophage accumulation in the peritoneal cavity and plaque forming cells of the spleen cells. It was named lyophyllan after the genus name.

• Archives of Pharmacal Research
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• 제19권2호
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• pp.132-136
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• 1996

Exogenously applied oxygen free radical generating agent, pyrogallol, highly elevated extracellular glutamate accumulation and augmented N-methyl-D-aspartate (NMDA)-induced glutamate accumulation in cerebellar granule neuronal cells, but did not in astrocytes. Superoxide dismutase remarkably decreased the pyrogallol-induced glutamate accumulation, but either NMDA or kainate antagonists did not. In addition, pyrogallol did not affect the NMDAinduced intracellular calcium elevation. Pyrogallol partially blocked glutamate uptake into astrocytes. These results suggest that oxygen free radicals elevate extracellular glutamate accumulation by stimulating the release of glutamate as well as blocking the glutamate uptake.

• Preventive Nutrition and Food Science
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• 제6권1호
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• pp.19-22
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• 2001

Conjugated linoleic acid (CLA) exhibits potent anti-carcinogenic and other biological activities in several animal models. We report here that dietary CLA, chemically synthesized from corn oil, accumulates I silkworm, Bombyx mori, which is used as therapeutic agent for diabetes in Korea and Japan. Mulberry leaves treated with 0.1 or 10% CLA in ethanol were supplied to silkworms from the end of 3rd instar to the 3rd day of the 5th instar. Fresh mulberry leaves or leaves treated with 10% corn oil in ethanol were fed as a check treatment. the amount of total lipids in the larval body ranged from 17.4 to 19.1mg/g of body tissue, which was not significantly affected by the source of the diets. No CLA was found in the control silkworms. But the level of CLA significantly increased to 83.5 mg/g of fat, when fed with mulberry leaves treated with 10% CLA. Only trace amounts of CLA were detected in the larvae reared with check leaves and 0.1% CLA-treated leaves. Mulberry leaves treatd with corn oil or CLA were not palatable to the larvae, resulting in a reduction of larval weight. These results suggest that silkworms containing CLA in body lipids could be producted by dietary CLA.

• 한국식품영양과학회지
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• 제23권5호
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• pp.784-791
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• 1994

This study was to investigate the cadmium removal effect of Korean green tea, black tea and oolong tea beverage on Cd administered rat, tissues and their excretions. Male Sprague-Dawley rats weighing 143±3.2g were divided into control and experimental groups. The control group were fed standard diet without cadmium . The experimental groups, which were fed standard diet containing 40 ppm Cd, were divided into 4 subgroups again , which were the groups given distilled water (CD group), 5% black tea (BT group), oolong tea (OT group ) and green tea (GT group), respectively. Five days before to sacrifice the rats, all 4 cadmium fed groups were supplied 1 ml of water with 600ppm Cd and control group were fed 1 ml of distilled water without Cd under the same dietary condition. After that, their excretion were collected separately for 3 days. In rat liver and kidney, accmulation of cadmium in 4 Cd administered groups were more than in control group and that of GT group was significantly less than CD group. In bone , also, accumulation of cadmium in 4 Cd administered groups was more than in control group and that of GT, OT,BT groups were much less than that of CD group. GT group was excreted more Cd in urine than Cd group. In feces, 3 tea feeding groups (BT, OT, GT group) were excreted Cd 1.7, 2.1, 2.4 times more than that of the CD group, respectively. We conclude that cadmium accumulations of GT feeding group in rat's liver, kidney and bone were much less than CD group , and the absorption and retention rate of GT group was significantly lower than CD group.

• 대한수의학회지
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• 제34권3호
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• pp.635-645
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• 1994

The environmental pollution by heavy metals has become a significant hygenic problem. Recently it is said the garlic supplementation in diet have protective effect on the heavy metal accumulation in tissue of rat by a researcher. In this study two experiments were undertaken. Firstly, dogs were fed diet supplemented with cadmium of cadmium plus 7% of raw garlic for 50 days. on the 50th day of experiment all dogs were euthanasied and the cadmium content of various tissue were measured by atomic absorption spectrophotometeric method. Secondly, in order to find out the toxic effect of garlic dogs were fed diet supplemented with 7% of raw garlic for 50 days and hematological or hematochemical observations were undertaken at 10 day intervals. The results obtained from these experiments were summarized as follows; 1. In dogs treated with cadmium and cadmium plus garlic cadmium was accumulated in renal cortex, liver, and muscle. However the concentrations of cadmium showed no significant between the two group. 2. In dogs fed diets supplemented with 7% of raw garlic significant decrease of erythrocyte count, packed cell volume and hemoglobin content and significant increase of Heinz body erythrocyte and reticulocyte count were recognized. 3. The garlic-treated dogs and control dogs had normal asparate aminotransferase, alanine aminotransferase, alkaline phosphotase, blood urea nitrogen value. The value showed no significant difference between the two group. 4. From these results it may be concluded that the garlic have protective effect for cadmium accmulation in tissue and excess garlic in diet could induce hemolytic anemia in dogs.

• 한국동물학회지
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• 제36권3호
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• pp.416-424
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• 1993

홍모기 난소에서 일어나는 난황단백질의 합성을 조사하였다. 지방체의 난황단백질합성양과 난소에 축적되는 난황단백질의 양을 rocket immunoelectorphoresis 방법과 in vitro organ culture 방법으로 조사한 결과 지방체에서의 난황단백질 합성을 흡혈 후 6시간째 부터 시작되어 24시간에 최대의 합성양을 나타낸 후 48시간 이내에 완료되었으며, 난소내로의 축적은 6시간부터 시작되어 60시간까지 계속되었다. 흡혈 후 0, 24, 48, 72시간된 난소추출물을 전기영동 및 Western blotting한 결과 24시간된 난소에서는 한종류의 난황단백질이 존재한 반면, 48, 72시간된 난소에서는 두종류의 난황단백질이 나타났다. 흡혈 후 48시간된 난소와 지방체를 $^3$H-leucine이 함유된 배지에서 배양하였을 때 지방체에서는 단백질의 합성이 거의 일어나지 않았으나 난소에서는 난황단백질을 포함한 다량의 단백질합성이 일어났다. Crossed immunoelectrophoreses의 결가 YP1과 YP2는 분자량에서는 차이를 보이나 면역성은 동일한 것으로 나타났다. 이상의 결과 홍모기에서는 난소에서도 난황단백질의 합성이 일어나는 것으로 나타났다.

• 생명과학회지
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• 제17권6호통권86호
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• pp.847-858
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• 2007

ER-Golgi 분비 경로를 통해서 정확한 구조를 가지면서 post-translational modification 과정을 거친 재조합 단백질의 발현을 최대화하는 것은 ER stress반응에 대한 연구의 중요한 계기가 된다. 세포가 스트레스를 받지 않는 상태라도 ER stress signaling은 재조합 단백질의 생산량을 제한하고 품질을 떨어뜨리는 여러 가지 조건을 만들게 된다. ER stress signaling을 막는 여러 가지 방법들이 제시되고 있으며 표 2는 이러한 방법들 중 일부를 나타내고 있다. 일반적으로는 pro-survival 경로에 관련되어 있는 인자를 촉진하고 pro-apoptosis에 관련되어 있는 인자를 억제하는 것들이다. 그러나 ER stress 반응은 매우 복잡하고 적응과 사멸 기작(adaptation and elimination mechanism)의 중간 역할을 하기 때문에 ER stress에 관련된 주요 인자를 산업적으로 응용하기 위해선 이들의 기능에 대해 보다 깊은 연구가 이루어져야 한다. 현재까지 재조합단백질의 생산량을 최대한으로 높이는 방법은 ER stress 반응이 생기지 않도록 fed-batch process를 개선하고 세포 사멸 기작을 조절하며 단백질의 glycosylation 처리를 하는 것이다.

• 한국작물학회지
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• 제37권1호
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• pp.45-53
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• 1992

우리나라에 육성보급하고 있는 대표적인 벼품종으로 Japonica$\times$Japonica 교잡인 일반형품종 2품종(추청, 화진)과 Indica$\times$Japonica 원연교잡으로 육성한 통일형품종 2품종(삼강, 칠성)을 공시 하여 광합성 및 물질생산특성과 이와 관련된 주요 생리적특성을 구명코져 온도와 광도 조건을 달리하여 생육특기별로 실험한 결과 그 개요를 들어보면 다음과 같다. 2. 유묘기에 있어서도 통일형 품종은 일반형품종에 비하여 저온에서 광합성능력이 저하되나 상온에서는 오히려 높았다. 3. 저온에 의한 호흡율의 저하는 유묘기, 분얼기 모두 품종간 차이는 적으나 유묘기보다 분얼기에 저하정도가 큰 특징을 보였다. 4. 생육단계별 specific leaf area는 품종간에 큰 차이없이 분얼기가 가장 높고 유수변화기에서 출수기에 갈수록 높아지는 특성을 보였다. 5. 출수기의 광합성능력은 7KLx의 저광도에서는 일반형품종이 통일형품종 보다 조해도가 낮으나 60KLx의 광도하에서는 통일성품종이 높았으며 특히 2위엽에서 높은 특성을 보였다. 6. 출수기의 엽위별 광합성에 호흡율(R/P$\times$100)은 3위엽에서 현저히 높았고 품종간에도 그경향은 일정하였다. 7. CGR는 전반적으로 통일형품종이 일반형품종에 비하여 높았고 RGR는 품종간에 대차가 없었으나 NAR는 통일형인 삼강에서 현저히 높았다. 8. 통일형품종이 일반형품종에 비하여 1수영화수 및 주당 정조중도 많았고 수확지수도 높은 특성을 보여 주었다.