• Journal of Plant Biotechnology
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• v.31 no.2
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• pp.169-173
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• 2004

Parenchyma cells of Streptanthus tortus suspension cultures possessed the different transport system for aldose-formed D-glucose and for ketose-formed D-fructose. $K_{m}$ value for D-glucose and D-fructose were 0.28mM and 15.02mM, respectively. $K_{m}$ value of D-mannose was 0.44 mM which is similar to the D-glucose transport system, but D-mannose was transported also through its own special uptake system. Parenchyma cells possessed the transport system of L-glucose, but the function of L-glucose was not known at all. Protoplast of parenchyma cells possessed only the monosugars transport system, but didn't possess the disugars, sucrose transport system. Early developing phloem protoplasts possessed glucose and sucrose transport system at the same time. On the contrary, in the complete developed phloem cells disappeared preexisted glucose transport system in the parenchyma cells, only new induced sucrose transport system existed.ted.

• Journal of Microbiology
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• v.40 no.1
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• pp.33-37
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• 2002

An enzymatic reaction for the production of D-alanine from D-aspartic acid and pyruvate as substrates by a thermostable D-amino acid aminotransferase (D-AAT) was investigated at various conditions In the temperature range of 40-70$\^{C}$ and pH range of 6.0-9.5. The D-AAT was produced with recombinant E. coli BL21, which hosted the chimeric plasmid pTLK2 harboring the D-AAT from the novel thermophilic Bacillus sp. LK-2. The enzyme reaction was shown to follow the Ping Pong Bi Bi mechanism. The K$\_$m/ values for D-aspartic acid and pyruvate were 4.38 mar and 0.72 mM, respectively. It was observed that competitive inhibition by D-alanine, the product of this reaction, was evident with the inhibition constant K$\_$i/ value of 0.1 mM. A unique feature of this reaction scheme is that the decorboxylation of oxaloacetic acid, one of the products, spontaneously produces pyruvate. Therefore, only a catalytic amount of pyruvate is necessary for the enzyme conversion reaction to proceed. A typical time-course kinetic study skewed that D-alanine up to 88 mM could be produced from 100 mM of D-aspartic acid with a molar yield of 1.0.

• Journal of the Korean Mathematical Society
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• v.33 no.4
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• pp.801-811
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• 1996

Let $Z^d$ denote the set of all d-tuples of integers$(d \geq 1, a positive integer)$. The points in $Z^d$ will be denoted by $\underline{m},\underline{n}$, etc., or sometime, when necessary, more explicitly by $(m_1, m_2, \cdots, m_d)$, $(n_1, n_2, \cdots, n_d)$ etc. $Z^d$ is partially ordered by stipulating $\underline{m} \underline{<}\underline{n} iff m_i \leq n_i$ for each i, $1 \leq i \leq d$.

• Horticultural Science & Technology
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• v.29 no.4
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• pp.311-316
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• 2011

This study aimed to determine the effect of EC (electrical conductivity) levels of nutrient solution in hydroponic culture on allyl-isothiocyanate (AITC) content within plant tissues, Vitamin C content and physiological responses in wasabi plant (Wasabia japonica M. 'Darma'). The 'Darma' was grown for 5 weeks with a deep flow technique (DFT) system controlled at 5 different EC levels, including 0.5, 1, 2, 3, and $5dS{\cdot}m^{-1}$. In result, the highest total content of AITC showed at EC level 5 and $3dS{\cdot}m^{-1}$ for 1 or 5- week, respectively. The total content of AITC increased about 1.2-1.4 times when the plants were grown in the EC levels between 0.5 and $2dS{\cdot}m^{-1}$, whereas the content decreased about 6 and 56 % in the EC level 3 and $5dS{\cdot}m^{-1}$, respectively. The content of AITC was relatively higher in petiole tissue, about 53 %, taken from 1 week-grown plants when the EC was controlled between 0.5 and $2dS{\cdot}m^{-1}$. Root tissue also had relatively higher content of AITC, about 45.1 %, when the EC was controlled at 3 and $5dS{\cdot}m^{-1}$. However, a 5-fold decrease in the AITC content was found in blade tissue and a 6.8-fold decrease in root when the EC was controlled at $5dS{\cdot}m^{-1}$ for 5 weeks. There was no significant difference in the vitamin C content in 1-week grown leaf tissues under the different EC level treatments; but, the content increased about 27% in 5-week grown plants at the EC level between 0.5 and $2dS{\cdot}m^{-1}$, compared to the 1 week-grown leaf tissue. Electrolyte leakage of leaf tissue taken from 3-week grown plant was 3-fold higher at the EC level $5dS{\cdot}m^{-1}$, compared to the EC level between 0.5 and $2dS{\cdot}m^{-1}$. Chlorophyll content, photosynthesis rate and transpiration rate were decreased when the EC was controlled at higher than $2dS{\cdot}m^{-1}$. Leaf water content, specific leaf area and growth were decreased when the EC was controlled at $5dS{\cdot}m^{-1}$ for 5 weeks. All the integrated results in this study suggest that the EC level of nutrient solution should be maintained at lower than $3dS{\cdot}m^{-1}$ in order to improve nutritional value and quantity required for hydroponically grown wasabi as functional vegetable.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.192.2-192.2
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• 2003

Apigenin-7-O-${\beta}$-D-glucoside, chrysoeriol, and luteolin were isolated from the aqueous ethanolic extract of Zostera marina L. leaves as the scavengers of reactive oxygen species (ROS) with the SC$\_$50/ values of 0.18 mM, 0.68 mM, and 0.18 mM against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 0.04 mM, 0.03 mM, and 0.01 mM against superoxide radicals in the xanthine/xanthine oxidase system, respectively. The luteolin suppressed the expression of matrix metalloproteinase-1 (MMP-1) up to 44% at 4.0 ${\mu}$M. (omitted)

• Biomolecules & Therapeutics
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• v.1 no.1
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• pp.71-76
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• 1993

It has been reported that d-limonene inhibits chemical-induced rat mammary cancer by the mechanism of increases in detoxification enzymes such as glutathione S-transferases and that cineole fails to exhibit significant suppressive effect on chemical-induced carcinogenesis. The present study was designed to compare the effects of d-limonene and cineole on the benzo(a)pyrene (BP)-induced mutagenicity, BP metabolism and lipid peroxidation. Modified Ames assay was employed to evaluate the inhibitory effect of d-limonene and cineole on the BP-induced mutagenicity. The number of revertant-bearing wells was decreased by 44~77% in the presence of both BP and d-limonene compared with that of BP alone whereas cineole decreased the number of revertant-bearing wells by 28~45% at the concentrations between $2{\mu}m$m.TEX> and 2 mM. d-Limonene suppressed BP metabolism by 16, 54 and 67% at 1, 10 and 100 mM, respectively while cineole inhibited the metabolism by 16, 26 and 55% at the same concentrations. The $EC_{50}$ values for d-limonene and cineole in inhibiting lipid peroxidation were 2.0 mM and 16 mM respectively, as assayed by thiobarbituric acid method. The present study showed that d-limonene and cineole have common antimutagenic effects although d-limonone appeared to be more effective than cineole in suppressing mutation and lipid peroxidation. The results suggest that the antimutagenic effects of d-limonene and cineole may be associated with alternation in enzyme activities and with inhibition of lipid peroxidation.

• Horticultural Science & Technology
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• v.29 no.1
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• pp.23-28
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• 2011

Experiments were conducted to investigate the optimum concentration of the nutrient solution in strawberry 'Sulhyang' with hydroponics in relationship between root activity and nutrient concentrations. Nutrient solutions for strawberry, made by Yamazaki, were supplied EC 0.5, 1.0, 2.0 $dS{\cdot}m^{-1}$ during experiment period. Growth of shoot and root of strawberries grown in visible plastic pot was observed during experiment. Petiole length was longest in plants grown in EC 1.0 $dS{\cdot}m^{-1}$, followed by 2.0 and 0.5 $dS{\cdot}m^{-1}$. Leaf width was longest in plants grown in EC 1.0 $dS{\cdot}m^{-1}$, followed by 0.5 and 2.0 $dS{\cdot}m^{-1}$. Fruit length, fruit diameter, fruit weight and yield were higher in EC 0.5 and 1.0 $dS{\cdot}m^{-1}$ than 2.0 $dS{\cdot}m^{-1}$ treatment but, soluble solids of the fruit did not show statistical differences among treatments. Shoot dry weight was heaviest in EC 1.0 $dS{\cdot}m^{-1}$, followed by 0.5 and 2.0 $dS{\cdot}m^{-1}$. Root dry weight was heavier in EC 0.5 and 1.0 $dS{\cdot}m^{-1}$ but significantly light in 2.0 $dS{\cdot}m^{-1}$. pH of the drainage solution was elevated in low nutrient concentration and lowered in high concentration. Also root activity was high in low nutrient concentration and low in high concentration. As a result, the optimum EC for strawberry 'Sulhyang' was EC 1.0 $dS{\cdot}m^{-1}$ in this experiment. It was confirmed that there was high relationship between root activity and pH of drainage solution. This result will be utilized as an indicator for strawberry hydroponics.

• 대한핵의학회:학술대회논문집
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• 1990.04a
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• pp.193.1-193.1
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• 1990

• 대한핵의학회:학술대회논문집
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• 1989.06a
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• pp.137.2-137.2
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• 1989

• The Korean Journal of Nuclear Medicine Technology
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• v.22 no.1
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• pp.80-83
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• 2018

Purpose Assessment of Serum Thyroglobulin (sTg) value in total thyroidectomy patients having an ablation dose of radioactive iodine indicates remaining cancer or metastasis. Especially, sTg in patients on withdrawal thyroxine or thyrogen administration for radioiodine ablation is an important indicator to determine the direction of further treatment and prognosis. Current guidelines suggest measurement of sTg is performed at 72 hours after the last injection of thyrogen. and assumes that sTg reaches maximum serum levels at that time. The purpose of this study is to evaluate the variation of sTg measured after thyrogen administration. Materials and Methods We compared with sTg performed at 24hours(D0) and 72hours(D2) after the last injection of thyrogen. We reviewed D0 and D2 from 276 patients were divided them into three groups according to ablation dose of radioactive iodine, 5mCi(A group), 30~80mCi(B group) and 100~200mCi(C group). We used T-test for comparison between D0 and D2. sTg was measured in serum using immunoradiometric assay (Tg-plus RIA; BRAHMS, Berlin, Germany). Results There is no critical variation between D0 and D2 in A group(n=100)(P=0.32), The case of increase(D2>D0) is 45, no change(D2=D0) is 23, decrease(D2D0 is 91, D2=D0 is 28, D2D0 is 19, D2=D0 is 2. The biggest increase is 143.6 ng/mL from 98.4 to 242. Conclusion There was a significant difference in the group over 30mCi. and the case of D2>D0 is 45%, 58.7%, 90.5% for each group. therefore, D2 increased as the dose of radioactive iodine increased. Furthermore, the most sTg values of D0 and D2 are variation under 2.0 ng/mL, so reproducibility as well as sensitivity of sTg will be important at values below 2ng/mL.