• The Journal of Korean Medicine
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• v.24 no.4
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• pp.87-91
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• 2003

Objectives: To examine the relaxational response to the water extract of Rheum palmatum L. and Rheum undulatum L. on rat thoracic aorta and abdominal aorta. Methods: Segments of thoracic aorta and abdominal aorta obtained from rats immediately after delivery were mounted in organ baths superfused on a polygraph. Results : We found that the thoracic aorta segments responded to the water extract of genus Rheum with a dose-dependent vasorelaxation. At $10^{-4}$ M 5-HT, the maximal contraction force was 93.5% of the maximum KCI-response. The 5-HT induced contractions at $10^{-4}$ M were inhibited by 86.4% and 62.1 % after addition of the high concentrations of R. palmatum root (RPR) and leaf (RPL) and R. undulatum root (RUR) and leaf (RUL). At 10 mg/ml RPR and RUR, the relaxational response at thoracic aorta and abdominal aorta with and without endothelium were 86.4%, 83.2%, 85.8%, and 62.1% of the maximum 5-HT induced contraction. Conclusion: Our result showed that RPL and RUL induced dose-dependent vasorelaxation on rat thoracic aorta and abdominal aorta, and that RPL and RUL roots have more potent effects than the leaves.

• Korean Journal of Plant Resources
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• v.21 no.6
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• pp.444-448
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• 2008

An adventitious root formation protocol from Smilax china L. was established for in vitro production of dioscin, a steroidal saponin having various bioactivities such as anticancer, antifungal, antiviral, and antiobesity. Optimal medium for root initiation from leaf explant was MS medium containing $30\;g{\cdot}L^{-1}$ of sucrose supplemented with $1.0\;mg{\cdot}L^{-1}$ kinetin + $2.0\;mg{\cdot}L^{-1}$ NAA. The induction of adventitious roots from in vitro initiated root segments was most favorable to MS liquid medium with $0.1\;mg{\cdot}L^{-1}$ kinetin + $2.0\;mg{\cdot}L^{-1}$ NAA. Among the 20 different adventitious roots originated from different plants, strain No. 10 was selected based on production ability of dioscin, and its stability through the successive suspension culture. The maximum growth stage of adventitious roots was noticed at 5 weeks after subculture while that of dioscin production in the adventitious root was at 7 weeks after subculture in suspension culture system. These results provide that suspension culture of adventitious roots of Smilax china L. have a potential for in vitro mass production of dioscin.

• Journal of Korean Neurosurgical Society
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• v.48 no.3
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• pp.193-198
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• 2010

Objective : The purpose of this study is to compare the incidence of possible complications of cervical lateral screw fixation and the achievements of bicortical purchase using the Roy-Camille, Magerl and the modified methods. Methods : Six fresh-frozen cervical spine segments were harvested. The Roy-Camille technique was applied to C3 and C4, and the Magerl technique was applied to C5, C6, and C7 of one side of each cadaver. The modified technique was applied to the other side of each cadaver. The nerve root injury, violation of the facet joint, vertebral artery injury, and the bicortication were examined at each screwing level. Results : No vertebral artery injury was observed in any of the three methods. One nerve root injury was observed in each cervical spine segment using the Roy-Camille method (8.3%), the Magerl method (5.6%), and the modified method (3.3%). Facet joint injuries were observed in two cervical spinal segments using the Roy-Camille method (16.7%) and three with the Magerl method (16.7%), while five facet joint violations occurred when using the modified method (16.7%). Bicortical purchases were achieved on ten cervical spinal segments with the Roy-Camille method (83.3%) and Magerl method (55.6%), while twenty bicortical purchases were achieved in the modified method (66.7%). Conclusion : The advantages of the modified method are that it is performed by using given anatomical structures and that the complication rate is as low as those of other known methods. This modified method can be performed easily and safely without fluoroscopic assistance for the treatment of many cervical diseases.

• Korean Journal of Medicinal Crop Science
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• v.12 no.6
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• pp.448-453
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• 2004

Transformed roots of Schisandra chinensis were obtained following co-cultivation of in vitro cultivated plantlet segments with Agrobaterium rhizogens ATCC15834. This root was examined for its growth and gomisin J contents under various culture conditions. Among the six basal culture media tested, WPM (Lloyd & McCown, 1980) medium supplemented with 5% sucrose was the best roots growth 6.2 (g D.W/flask) and gomisin J accumulation 1.56 $(X10^{-3}\;ug/g\;D.W)$. Initial inoculum size correlated with the yield of biomass while gomisin J contents was not affect. Gomisin J production was influenced by the initial sucrose concentration and the highest production yield was achieved at the concentration of 7%. The optimal shaking speeds for roots growth and gomisin J production was 120 and 140 rpm, respectively.

• Plant Resources
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• v.4 no.1
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• pp.53-58
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• 2001

The effect of carbenicillin on the dedifferentiation and the regeneration efficiency of plant tissues of horseradish(Armoracia rusticana) was evaluated, Inhibition effect for callus initiation was observed when leaf blade, root and petiole segments were grown on MS medium containing 500 mg/L to 2000 mg/L carbenicillin and 0.5 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D). The regeneration of horseradish shoots from leaf blade, root and petiole explants were decreased as the addition of carbenicillin increased from 1000 mg/L to 2000 mg/L in MS medium containing 0.5 mg/L of 6-benzylaminopurine (BAP) or kinetin. Especially, 500 mg/L carbenicillin treatment significantly inhibited shoot induction when leaf blade explants were grown on hormone-free MS medium. It was suggested that the toxic effects of combinations of carbenicillin and 2,4-D may be due to high auxin activity levels.

• Mycobiology
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• v.33 no.1
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• pp.41-50
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• 2005

Results from an innovative approach to improve remediation in the rhizosphere by encouraging healthy plant growth and thus enhancing microbial activity are reported. The effect of arbuscular mycorrhizal fungi (Am) on remediation efficacy of wheat, mungbean and eggplant grown in soil spiked with polyaromatic hydrocarbons (PAH) was assessed in a pot experiment. The results of this study showed that Am inoculation enhanced dissipation amount of PAHs in planted soil, plant uptake PAHs, dissipation amount of PAHs in planted versus unplanted spiked soil and loss of PAHs by the plant-promoted biodegradation. A number of parameters were monitored including plant shoot and root dry weight, plant tissue water content, plant chlorophyll, root lipid content, oxido-reductase enzyme activities in plant and soil rhizosphere and total microbial count in the rhizospheric soil. The observed physiological data indicate that plant growth and tolerance increased with Am, but reduced by PAH. This was reflected by levels of mycorrhizal root colonization which were higher for mungbean, moderate for wheat and low for eggplant. Levels of Am colonization increased on mungbean > wheat > eggplant. This is consistent with the efficacy of plant in dissipation of PAHs in spiked soil. Highly significant positive correlations were shown between of arbuscular formation in root segments (A)) and plant water content, root lipids, peroxidase, catalase polyphenol oxidase and total microbial count in soil rhizosphere as well as PAH dissipation in spiked soil. As consequence of the treatment with Am, the plants provide a greater sink for the contaminants since they are better able to survive and grow.

• The Korean Journal of Pain
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• v.9 no.2
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• pp.412-414
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• 1996

Herpes zoster is an infection by the varicella zoster virus in a partly immune compromised person such as old age, cancer, immune deficiency disease. When either the upper lumbar or sacral segments are involved, serious urinary retention caused by central spread of herpes zoster from dorsal root ganglion can occur. The urinary disturbance appears to have been due to motor dysfunction of detrusor muscle, trigone muscle, and internal sphincter. We experienced two cases of zoster affecting different segments of the spinal cord and resulting in urinary retention.

• Speech Sciences
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• v.8 no.1
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• pp.77-91
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• 2001

This paper investigates the timing of Korean spoken in a news-reading speech style in order to improve the naturalness of durations used in Korean speech synthesis. Each segment in a corpus of 671 read sentences was annotated with 69 segmental and prosodic features so that the measured duration could be correlated with the context in which it occurred. A CART model based on the features showed a correlation coefficient of 0.79 with an RMSE (root mean squared prediction error) of 23 ms between actual and predicted durations in reserved test data. These results are comparable with recent published results in Korean and similar to results found in other languages. An analysis of the classification tree shows that phrasal structure has the greatest effect on the segment duration, followed by syllable structure and the manner features of surrounding segments. The place features of surrounding segments only have small effects. The model has application in Korean speech synthesis systems.

• Structural Engineering and Mechanics
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• v.3 no.5
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• pp.445-462
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• 1995

Previous studies of a stepped cantilever with two straight segments under a suddenly applied constant force (a step load) applied at its tip have shown that the validity of deformation mechanisms is governed by certain geometrical restrictions. Single and double-hinge mechanisms have been proposed and it is shown in this paper that for a stepped cantilever with a stronger tip segment, i.e. $M_{0.1}$ > $M_{0.2}$, where $M_{0.1}$ and $M_{0.2}$ are the dynamic fully plastic bending moments of the tip and root segments, respectively, the family of possible yield mechanisms is expanded by introducing new double and triple-hinge mechanisms. With the aid of these mechanisms, it is shown that all initial deformations can be derived for a stepped cantilever regardless of its geometry and the magnitude of the dynamic force applied.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2003.05a
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• pp.206-213
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• 2003

Application of existing decision tree algorithms for Internet retail customer classification is apt to construct a bushy tree due to imprecise source data. Even excessive analysis may not guarantee the effectiveness of the business although the results are derived from fully detailed segments. Thus, it is necessary to determine the appropriate number of segments with a certain level of abstraction. In this study, we developed a stopping rule that considers the total amount of information gained while generating a rule tree. In addition to forwarding from root to intermediate nodes with a certain level of abstraction, the decision tree is investigated by the backtracking pruning method with misclassification loss information.