• Journal of Pharmaceutical Investigation
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• v.34 no.3
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• pp.185-192
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• 2004

The objective of this study was to evaluate the effects of surfactant type and concentration upon dissolution rates of carbamazepine from an immediate-release tablet. The dissolution media used in this study were aqueous solutions containing 0.1-2% sodium lauryl sulfate, cetyltrimethylammonium bromide, or polysorbate 80. The solubility of carbamazepine in the dissolution media was determined at first. A dissolution study was then conducted by using the USP dissolution apparatus II (paddle method) with an agitation rate of 75 rpm. Aliquots of the dissolution media were taken at predetermined time intervals, and the amount of carbamazepine dissolved was measured spectrophotometrically at 285 nm. The dissolution data obtained were fitted into a biphasic exponential equation with four parameters. Excellent correlations were observed between the experimental data and the theoretical ones predicted by the equation. This equation permitted the calculation of $T_{50%}$ (the time required for dissolving 50% of carbamazepine) under various experimental conditions. Differentiation of the equation also led to the attainment of dissolution rates at dissolution time points. The addition of a surfactant to an aqueous solution led to increasing the solubility of carbamazepine by 3- to 12-folds, depending upon its type and concentration. This event also resulted in enhancing the magnitude of a sink condition during the dissolution study. As a result, the dissolution rate of carbamazepine was affected by the aqueous surfactant concentration in a proportional manner. Subsequently, $T_{50%}$ values declined rapidly, as the surfactant concentration increased. Such effects were observed in decreasing order of sodium lauryl sulfate, cetyltirmethylammonium bromide, and polysorbate 80. These results clearly demonstrated that it was possible to tailor a dissolution rate and $T_{50%}$ of carbamazepine by manipulating the type and concentration of a surfactant. Relevant information would be beneficial to setting up dissolution specifications for poorly water-soluble drug products.

• Korean Journal of Food Science and Technology
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• v.12 no.2
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• pp.133-139
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• 1980

The extraction mechanism and extraction conditions of cellular lipid of freeze-dried cells of Rhodotorula rubra YUFE 1526, which was reported as coenzyme Q producing microorganism, were studied. 1. Methyl alcohol was the most appropriate solvent for extraction of cellular lipids and the resulting total lipid was 19.17 weight %. 2. When 1 % (w/v) of freeze-dried cell was extracted by methyl alcohol, the extraction yield was 90.49 % at $50^{\circ}C$ for 2 hr. 3. The diffusivity varied with extraction temperature and the empirical equation was derived as follows : $2.2e^{0-02907T}{\times}10^{-9}\;mm^2/min.$ 4. The diffusivity of cellular lipid of Rhodotorula rubra YUFE 1526 was $9.4{\times}10^{-9}\;mm^{2}/min.$ 5. The extraction model was well fitted on the extraction of cellular lipid.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.11 no.6
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• pp.678-683
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• 2018

This study deals with the analysis of a technology convergence of the IoT(Internet of Things) which is the key technology of the fourth industrial revolution. For this purpose, 77 patents with the Main Category CPC code G06Q50/10(Electronic Commerce Service) among the IoT patents filed after 2014 were analyzed. As a result of the Main-Sub Category analysis of CPC codes, the IoT has a strong relationship between "Electronic Commerce Service (G06Q50/10)" and G06Q(49 cases), H04L(40 cases), G08B(24 cases), G05B(21 cases), H04W(21 cases), H04N(16 cases), and so on. By using the methodology in this study, we can contribute the establishment of technology strategy and new value creation from the prediction of the possibility of the combination of technologies and to develop new patents among various new technologies.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.24 no.4
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• pp.1-14
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• 2021

This study suggested suitable soil textures that is proper to propagate native plants to manage and restore barren land in DMZ. Germination tests were conducted for 16 native herbaceous plants growing in the DMZ border area in accordance with FAO-BI (Biodiversity International) standards, and the germination rate and T₅₀ in vitro were investigated. In order to examine the germination characteristics according to the soil textures, we used gravel, bed and mixed soil and investigated the germination characteristics under ordinary room temperature conditions in the greenhouse. As a result, it was observed that the germination rate in the greenhouse was significantly decreased compared to the germination rate in vitro of the species advertised due to soil textures. T₅₀ between the in vitro and each soil texture showed significant differences whereas T₅₀ between soil textures alone did not in all species advertised. The germination rate in vitro of Aster koraiensis, Dendranthema zawadskii var. latilobum, Hosta clausa, and Hosta minor there was no significant difference compared to ordinary room temperature conditions. In addition, as the germination rate is demonstrated more than 70%, which is relatively higher than other species advertised, it is considered to have strong environmentally adaptable. On the other hand, considering that the 6 species of Leontopodium coreanum, Plantago major, Potentilla chinensis, Sedum kamtschaticum, Sedum latiovalifolium, and Veronica kiusiana demonstrated less than 50% of germination rate in vitro, it is expected to be difficult to propagate without pre-treatment. In order to use these 6 species as restoration material plants, it needs to be considered to pre-treat to improve germination rate, or to enhance the vitality of seeds by improving the seed gathering period and storage method.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.10
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• pp.1433-1438
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• 2002

The study was carried out to evaluate leucaena seeds as a protein replacement of mustard seed cake (MSC) in the concentrate mixture of growing lambs. Fifteen owing male lambs (Local${\times}$Corridale) with an average body weight of 16.3 kg were allocated into three dietary treatments (T1, T2, and T3) with five animals in each group. Animals were offered dry mixed grass, berseem hay and concentrate mixture to meet their nutrient requirements. In concentrate mixture of T1, (Control) MSC was used as protein source, while in T2 and T3 groups, 25 and 50% of MSC was replaced by leucaena leucocephala seeds. On completion of three months (90 days) of feeding, a digestion cum-metabolism trial was conducted to determine DMI, nutrient utilization, and nitrogen balance. Changes in body weight were recorded at 15 day internals and eating patterns were recorded for 3 consecutive days at the end of the feeding trial. MSC had higher CP contents than leucaena seeds (27.0%). Mimosine contents in leucaena seeds were 1.1 compared to 0.2 and 0.4% in concentrate mixture of T2 and T3 group, respectively. Dry matter intake varied non-significantly ($79.3{\pm}1.2$ to $83.4{\pm}1.3g/kg$ $w^{0.75}$) across the dietary treatments. Digestibility of DM and cell wall polysaccharides (NDF, ADF. Cellulose and hemicellulose) were comparable, however CP digestibility was relatively lower in leucaena luecocephala seeds based groups (T2 $45.5{\pm}1.7$ and T3 $46.7{\pm}3.5$) compared to MSC supplemented group (T1 $47.7{\pm}0.9%$). The growth rate of lambs was non-significantly higher in T1 ($79.2{\pm}5.4$) compared to T2 ($73.8{\pm}8.8$) and T3 ($73.9{\pm}7.0$), respectively. The animals were in positive nitrogen balance and N-balance varied from 1.8 to 2.9 g/d across treatment groups. The eating rate (% of total offered) of concentrate up-to 15 min was relatively higher in T1 (82.4) than T2 (74.2) and T3 (77.8%). However no effect of leucaena seeds was recorded on total DMI of animals. The results of the study revealed that the inclusion of up to 50% leucaena seeds, as protein source in concentrate mixture of lambs had no adverse effect on DMI, nutrient utilization, eating patterns, nitrogen balance and growth performance of lambs.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.585-589
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• 1994

The effects of T-2 toxin on mitogen-induced blastogenesis of chick splenic cells were investigated. The [$^3H$] thymidine incorporation in splenic cells stimulated by lipopolysaccharide and concanavalin A were equally inhibited as the concentration of T-2 toxin was increased. The effective dose of T-2 toxin causing a 50% reduction of [$^3H$] thymidine incorporation was inbetween 1.0 and 5.0 ng/ml for both mitogens. Mitogen-induced blastogenesis in chick splenic cells showed differences among experimental groups with different exposure time of T-2 toxin, exhibiting the most inhibition in the experimental group exposed to T-2 toxin at both embryonic and chick periods.

• Journal of Animal Environmental Science
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• v.5 no.3
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• pp.149-156
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• 1999

The experiment was conducted to determine the optimum stocking density for Korean Native Chicken. The experiment was carried out with 810 Korean Native Chickens for 16weeks from April 22. 1987 to August 11. 1987. The chickens were housed in pens with varying stocking densities; T1(20 birds per 3.3$m^2$), T2(30 birds per 3.3$m^2$), T3(40 birds per 3.3$m^2$), T4(50 birds per 3.3$m^2$), T5(60 birds per 3.3$m^2$) and T6(70 birds per 3.3$m^2$). Each treatment contained three replicates. At the end of the trial, the average body weight of T1 was significantly heavier than that of T5 (P<0.05), but there were no statistical differences among the treatments in fed intake. The feed conversion of T3 was improved significantly in comparison with that of T5(P<0.05), and the viability of T1 showed a significantly difference with that of T5, T1 showed the highest production number, whereas T5 the lowest one.

• Korean Journal of Plant Resources
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• v.31 no.3
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• pp.195-201
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• 2018

This study was executed to evaluate the phenolic content, DPPH radical scavenging rate, and the cytotoxic effect in human cancer cell, 3T3-L1 cell from C. lanceolata extracts at various ethanol concentration. Total polyphenol and flavonoid content of the C. lanceolata at various ethanol concentration showed the high amount in 70%, 100% ethanol extract. The DPPH radical scavenging activity progressively increased in a dose-dependent manner, and showed the highest in 100% ethanol extract. The cytotoxic effect against human cancer cell of the C. lanceolata was higher in 50% and 70% ethanol extracts. In particular, the cytotoxic effect in MCF-7 cell was relatively higher than in other cells. The $IC_{50}$ (concentration causing 50% cell death) value showed the highest on MCF-7 cell ($538.39{\mu}g/m{\ell}$ in 70% ethanol extract, and exhibited significant activity against Hela cell ($637.87{\mu}g/m{\ell}$, Calu-6 cell ($728.64{\mu}g/m{\ell}$. The extract of 70% ethanol at $1,000{\mu}g/m{\ell}$ exhibited a pronounced cytotoxic effect on 3T3-L1 cell comparable to that of the other extracts, and reduced in a concentration-dependent manner.

• Journal of the Korean Chemical Society
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• v.47 no.5
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• pp.460-465
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• 2003

Structural alteration of p53 and overexpression of p53 protein are the most common genetic abnormalities in various kinds of human cancer. Mutations in the p53 tumor-suppressor gene are usually associated with an advanced development of colorectal cancer characterized by the transition from the adenoma to carcinoma stage. Mutations in exons 5-8 of the p53 gene were analyzed by the polymerase chain reaction-single strand conformation polymorphism(PCR-SSCP) and denaturing high performance liquid chromatography(DHPLC). SSCP analysis detected 7 mutations(C13109>T) in 50 colorectal cancer samples(14%) at exon 5, and DHPLC analysis detected 7 mutations (C13109>T) and 2 mutation(C13202>A, C13204>G) in 50 colorectal cancer samples(18%) at exon 5. All of 9 mutations were proved by sequencing analysis. We conclude that DHPLC is a highly sensitive and specific method for p53 gene mutations.

• Journal of dental hygiene science
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• v.7 no.1
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• pp.31-35
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• 2007

Caesalpinia sappan L. (Leguminosae) is an oriental medicinal herb distributed in China and Taiwan, and its heartwood has been traditionally used as an analgesic, a therapy for thrombosis or tumor. This study was to investigate the proliferation and inhibition effects of Caesalpinia sappan extracts against human epithelial cell and cancer cell lines. The methanol extract of dried C. sappan heartwood was evaporated (KS-6), and then sequentially extracted by hexane (KS-01), chloroform (KS-02), ethyl acetate (KS-03), n-butanol (KS-04), and water (KS-05). After 48 hr of exposure, these fractions at a concentration of $50{\mu}g/ml$ significantly increased, and reduced cell proliferation in both human normal epithelial and cancer cell lines. The ethyl acetate fraction (KS-03) among organic solvent fractions was 120.2% of the most proliferation activity ($50{\mu}g/ml$) against HaCaT human epithelial cell. However, fractions from chloroform, butanolic and methanolic extract had 7.2, 28.7 and 20.8% of antiproliferative effect on HaCaT cell, respectively. In cell proliferation effects of C. sappan extract on HeLa, SiHa and C33A human cervical cancer cells, chloroform fraction (KS-2) was the most antiproliferative activity, its antiproliferative rate (dosage, $50{\mu}g/ml$) relative to control was 25.8, 12.2 and 17.4% for SiHa, HeLa and C33A, respectively. The results indicated that the six extract fractions could induce cell cycle stimulate or arrest in some way. Finally, further investigation is needed to assess the molecular mechanisms mediated anticancer activities of this plant.