• Environmental Mutagens and Carcinogens
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• v.10 no.2
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• pp.119-126
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• 1990

본 최기형시험은 엘라스타제가 임신토끼와 태자에 미치는 영향을 조사할 목적으로 수행되었다. 시험은 임신된 New Zealand White 종의 토끼를 2개의 대조군 (제 1, 제 2대조군)과 3개의 투여군 (제 1, 제 2, 제 3투여군)으로 나누어 실시되었다. 제 1, 제 2, 제 3투여군에는 각각 엘라스타제 1, 2, 12, 120mg/kg을 임신 6일부터 18일까지 연일 경구투여하였으며, 같은 기간동안 제 1대조군과 제 2대조군에는 각각 10% skim milk 수용액과 ethylene thiourea 40mg/kg을 경구투여하였다. 임신 29일에 모든 모동물을 도살하여 모체와 태자를 검색하였다. 시험기간중 제 2대조군에서는 사료섭취량이 유의성있게 감소되었다 (P<0.01). 시험결과 황체수, 착상수, 생존태자수, 태자의 성비, 태자 및 태반중량에 있어서 각 군간 유의성있는 변화가 관찰되지 않았으며 태자의 외형검사, 애부장기 및 골격 검사에서도 군간 유의성있게 변화가 관찰되지 않았다. 이상의 결과로 미루어 본 시험에서 채택한 엘라스타제의 용량은 토기에 있어서 최기형 유발능이 없는 것으로 판단된다.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.293-294
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• 2010

In this study, it was analyzed that autogenous expansion of MgO concrete was affected by W/B and curing temperature. Autogenous expansion test was performed for MgO concrete, which is mixed MgO of 0%, 5% of cement weight. With autogenous expansion based on long-term time variation was measured, it was observed an influence with W/B and curing temperature.

• Korean Journal of Veterinary Pathology
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• v.5 no.2
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• pp.39-42
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• 2001

A reference range data base containing organ weight values on animals used in 4 week and 13 week toxicity tests is described. Data listed include the values of minimum, maximum, mean and standard deviation for each of the following organ weights. Organs: Brain, heart, liver, spleen, kidney, adrenal gland, testis, ovary. This study was undertaken to determine organ weight reference values of Ktc: SD rats

• Proceedings of the Korea Information Processing Society Conference
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• 2014.04a
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• pp.865-868
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• 2014

사과나 배 등의 과일을 장기저장하거나 유통하는 과정에서 가장 문제가 되는 것은 내부갈변이나 부패 등의 내부결점이다. 내부결점은 사람의 육안이나 현행 중량선별방식으로는 식별이 불가능하며, 일부 보급된 내부품질 측정 장치는 고가의 외산장비가 대부분이다. 본 연구에서는 사과와 배의 갈변이나 부패 등의 내부결점을 비파괴적이면서도 저렴하게 검출할 수 있는 방법을 소개한다. 먼저 내부결점을 검출하기 위한 최적의 가시광 및 근적외선 파장대역을 선정하고 기존의 고가 외제 분광광도계를 대체할 수 있는 광다이오드를 선정하여 시작기를 개발한다. 시작기를 통한 실험에서 제안한 방법의 내부이상 판별 정확도는 90% 이상이었다.

• Korean journal of food and cookery science
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• v.15 no.3
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• pp.231-237
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• 1999

The anticancer effect of the bark of Broussonetia kazinoki root extracts (hexane. chloroform, ethylacetate, butanol, aqueous) were studied. The cytotoxicity by MTT assay and inhibitory effect on the growth of sarcoma 180 cells were tested in vitro. The reduction rate of the tumor formation and spleen/body weight rate on BALB/c mouse were tested in vivo. From the tests, each fraction showed the cytotoxic effect against the sarcoma 180 cells. In addition, as the concentration of the fractions increased, cytotoxic effect tendency increased as well. The cytotoxic rate of the hexane, chloroform, ethylacetate, butanol and aqueous fractions showed by 58.7%, 40.1%, 75.7%, 52.6% and 62.7% respectively after testing by MTT assay system. And sarcoma 180 cells were incubated for 6 days at 37$^{\circ}C$ with various concentrations of each fraction. As the incubation days go on, the number of cells increased, while the inhibition rate on the growth of sarcoma 180 cells were decreased. Especially the ethylacetate fraction at the concentration of 1.0 mg/ml strongly inhibited the growth of sarcoma 180 cells by 74% compared with the control for a day 37$^{\circ}C$ The hexane, chloroform, ethylacetate, butanol and aqueous fractions inhibited on the growth of sarcoma 180 cells by 31%, 19%, 60%, 30% and 42% respectively, when sarcoma 180 cells has been incubated for 6 days at 37$^{\circ}C$. The each fraction exhibited the antitumor effect in vivo. The ethylacetate fraction reduced the tumor formation by 41% compared with the control, when sarcoma 180 cells were injected subcutaneously into the left groin of BALB/c mice. Also spleen/body weight rate of ethylacetate fraction was increased by 2.10% compared with the control (1.08%). And it is considered that there would be no toxic effect caused by each fraction of body weight and organ as there was on more changes in mouse' weight compared with the control.

• Korean Journal of Environmental Agriculture
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• v.25 no.4
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• pp.382-385
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• 2006

To know the effect of water treatment sludge (WTS) as a rice seedling culture soil, rice seeds are sown, germinated and grown on the culture soils mixed with different ratios of WTS to sand (100:0, 50:50, 30:70, respectively), and their growth effects was compared to that of control, commercial culture soil. When WTS is used as a culture soil for rice, the length and weight of the top part of rice seedling somewhat decreased than those of control treatment while their root length and weight in all WTS treatments significantly increased. Although phosphorus and potassium uptake of rice seedling in WTS treatments was slightly decreased, WTS treatment showed to develop root growth which is necessary in the seedling stage of all plane. Such a stimulatory effect on root growth of rice seedling was significant in the mixture ratio of 50% WTS to 50% sand.

• Journal of Food Hygiene and Safety
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• v.13 no.3
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• pp.268-273
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• 1998

The present study has been undertaken to investigate the effects of ginseng extract on the activities of several enzymes in serum of rats fed lard and alcohol. Thirty-five males of Sprague-Dawley strains weighed about 130 g were divided into 7 groups, each group receiving a different diet for 10 weeks; i.e. basal diet plus 15% lard, basal diet plus 5% alcohol, basal diet plus 5% ginseng extract, basal diet plus 15% lard and 5% ginseng extract. Determinations were carried out on the net weight gain, food efficiency ratio, weight of organs, and AST, ALT, lactate dehydrogenase, alkaline phosphatase activities in serum of rats. The results obtained were as follows:Rats given feed containing lard and alcohol showed significant decrease in net weight gain, but ginseng extract caused an increase in food efficiency ratio. Lard supplementation caused an increase in the weight of liver, kidney, spleen, but another groups did not. AST, ALT, ALP, LDH of serum were significantly increased in lard and alcohol containing group but ginseng extract feeding decreased enzyme activities compared to lard and alcohol containing group. The above results suggest that ginseng extract would prevent the metabolic disease of liver by preventing hyperlipemia caused by high fat diet.

• Journal of Korean Tunnelling and Underground Space Association
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• v.8 no.3
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• pp.237-247
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• 2006

The use of high-performance shotcrete lining is indispensable to improve long-term durability of a tunnel and to apply the single-shell tunnelling method. Among a lot of shotcrete admixtures, pozzolan materials such as silica fume have positive effects on increasing the strength and the durability of shotcrete. It is also well known that a cement-based accelerator is much faster in setting time and more eco-friendly than conventional accelerators. This study aimed to improve the properties of wet-mix shotcrete by incorporating with Metakaolin and the calcium aluminate based accelerator. To compare Metakaolin with silica fume, mixing ratios of each material were varied as 4% and 8% of cement weight. Moreover, Metakaolin was blended with silica fume, and their binder was also set to 4% and 8% of cement weight. At each mixing condition, setting time, compressive strength, flexural strength, permeability and freezing-thawing resistance were measured. From the experiments, it was revealed Metakaolin could be a substituting material for silica fume.

• Journal of the Korean GEO-environmental Society
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• v.21 no.11
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• pp.11-20
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• 2020

For water barrier and reinforcing grout in soft ground, the verification of durability was conducted over the initial and long-term ages under various curing conditions. The grout was made of water glass system, fast-hardening mineral (FHM) system, and acrylic polymer system. There were three types of curing conditions that were tab water curing, artificial seawater curing, and atmospheric curing. And the various tests were performed for each sample by age, uniaxial compressive strength, length change, and weight change. As artificial seawater, MgCl₂ and MgSO₄ aqueous solutions were prepared and used, respectively. As the test results, the fast-hardening mineral system and acrylic polymer system were cured stably without significant change in durability in tap water and artificial sea water, whereas water glass system showed a very rapid drop in durability under artificial sea water conditions compared to tap water. In atmospheric curing conditions, durability is lowered compared to water curing in all cases, and in particular, the weight loss in the FHM system and water glass system is about 62% and 60%, respectively, resulting in a significant decrease in durability.

• Korean Journal of Plant Tissue Culture
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• v.26 no.4
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• pp.229-233
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• 1999

The possibility for long-term preservation of Larix leptolepis embryogenic tissue was tested in this study. Higher relative increase of the tissue fresh weight was observed when embryogenic tissue was pretreated for 24 hrs in a medium containing 0.4 M sorbitol or 20% polyethyleneglycol with cooling rate of -0.33$^{\circ}C$/min. The fast cooling rate of -0.5$^{\circ}C$ and -1.$0^{\circ}C$/min appeared to be less effective in regrowth of tissues from cryopreservation. No DNA variants have been observed by PCR analysis among the embryogenic tissues recovered after 1-, 7-, and 28-day-cryopreservation. The post-thaw embryogenic tissue gave rise to mature somatic embryos which developed into plants.