• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.180-180
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• 1993

소프트하이드로겔의 합성은 IR, DSC등으로 확인되었으며, 전연성의 물성을 나타내었다. PPO 하이드로겔은 대부분 수팽윤도가 10％미만 정도로서 야굴방출시 팽윤에 의한 변형도가 낮아 부착형, 또는 이식형 조절방출성 제제에의 활용도가 기대되었으며, 약물방출은 주로 가교도/주쇄연장도에 의한 고분자 네트？의 세공크기(mesh size)에 의해 조절되었다. IPN하이드로겔의 경우는 pH의존성이 일반적이 겔보다 현저하게 나타났으며, 하유된 약물이 물성에 따른 약물방출양상을 보였다.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.196-196
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• 1994

DDS에 활용될 수 있는 고분자 소재를 개발할 목적으로 물성 및 응용성이 우수한 고분자 겔에 관한 연구를 수행하였다. Ethylene oxide,propylene oxide 각각의 copolymer인 poloxamer등의 prepolymer들을 triisocyanate로 가교시키고 diisocyanate 로 chain이 연장된 "soft hydrogel"을 제조하였다. 모델 약물을 선정하여 crosslinker와 extender의 조절에 따른 hydrogel의 약물 방출 조절능을 조사하였으며 그 기전을 규명하고자 하였다. 가교부위에 urethane bond를 함유한 soft hydtogel은 건조상태에서도 고무와 같은 전연성을 보여 일반적인 hydrogel과 대비되는 특성을 보였으며 이에 따른 다양한 활용성이 기대되었다. Extender및 crosslinker의 비율에 따라서 이 rubber elasticity가 조절되었다. 가교도가 감소할수록 팽윤도가 상승하였고 이에 따른 약물방출도 증가함을 확인하였다. 또한 Prepolymer의 분자량 및 친수/소수성등의 물성에 따라 약물방출을 조절할 수 있었다. 제조된 hydrogel에 조절방출시 필요한 기능을 부가시키고자 poly(carylic acid)류와 IPN 공중합체를 합성하여 물성을 조사하였고 비이온성/양이온성/음이온성 모델약물을 선정하여 pH에 따른 가변적 팽윤도와 이온성 상호작용등에 근거한 약물 조절방출기전을 조사하였다.기전을 조사하였다.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.771-774
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• 2002

Highly sweep leading edge extensions(LEX) applied to delta wings have greatly improved the subsonic maneuverability of contemporary fighters. In this study, systematic approach by PIV experimental method within a circulating water channel was adopted to study the fundamental characteristics of induced vortex generation, development and its breakdown appearing on a delta wing model with or without LEX in terms of four angles of attack($15^{\circ},\;20^{\circ},\;25^{\circ},\;30^{\circ}$) and six measuring sections of chord length($30{\%},\;40{\%},\;50{\%},\;60{\%},\;70{\%},\;80{\%}$). Sideslip effect in case of the LEX was also studied for two sideslip(yaw) angles($5^{\circ},\;10^{\circ}$) at one angle of attack(20). Distribution of time-averaged velocity vectors and vorticity over the delta wing model were compared along the chord length direction. Quantitative comparison of the maximum vorticity featuring the induced pressure distribution were also conducted to clarify the significance of the LEX existence. Animation presentation in velocity distribution was also implemented to reveal the effect of LEX with wing vortex interaction.

• Korean Journal of Agricultural Science
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• v.3 no.1
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• pp.67-75
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• 1976

This experiment was studies for grassland establishment on west coastal saline land in Korea from May 1975 to March 1976 and used seeds were introduced from Australia. The results of adaptability were summarized as follow. 1. The seeds germination percentage was not influence in 0.5% salt included, but delayed days in 1% salt included and decreased germination percentage. 2. Any experimental grasses species were not growth on the 0.5% salt included soil and also growth was much damaged on the 0.05% salt included soil. It was suggested that $Mg^+$, $K^+$ ions involved with $Na^+$ ion. 3. The yield of grasses were much decreased on 0.05% salt included soil which compared control group. The yield rate of decrease were 30% in kikuyu, 60% in strawberry clover, 63% in reed canarry and 89% in orchard grass. 4. For winter-hardness test, nearly all the species well overwintered but except kikyu. 5. One of salt tolerance native grass (Agrostis distans crieseb var coreensis, Hackel) was discovered in saline area, and it was growth from middle of May to Middle of September. Also it was known that the native grass was good feed stuff but it was not so long in growth life. 6. It was concluded that more experimental work must be carried out to select of salt tolerance grass for grassland establishment on saline by introduce some more species such like saltgrass, saltbush, shadsclae from foreign land.

• The Korean Journal of Pain
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• v.18 no.1
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• pp.39-42
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• 2005

Background: Besides its general anesthetic effect, ketamine interacts with sodium channels in a local anesthetic-like fashion, including the sharing of binding sites with those commonly used by clinical local anesthetics. This study evaluated the dose related effects of ketamine during epidural anesthesia with 0.5% ropivacaine. Methods: Sixty ASA physical status I II patients, scheduled for minor elective surgery under epidural anesthesia using 0.5% ropivacaine, were randomly divided into three groups (n = 20 each). The patients initially received either 0.5% ropivacaine (group 1), ketamine (0.1 mg/kg) in addition to the epidural 0.5% ropivacaine (group 2) or ketamine (0.2 mg/kg) in addition to the epidural 0.5% ropivacaine (group 3). The regression of sensory block was assessed by transcutaneous electric stimulation (TES), equivalent to a surgical incision. Motor block was assessed using the Modified Bromage's scale. Episodes of bradycardia, hypotension and sedation were also recorded. Results: There were no significant differences among the three groups in the maximal levels of sensory block or the times taken for these levels to be reached. The mean times for the block to regress to two and four segments below the maximal level were significantly prolonged by epidural ketamine. Conclusions: Epidural ketamine prolongs the duration of ropivacaine epidural anesthesia. These results suggest that ketamine has local anesthetic-like actions.

• Journal of Hospice and Palliative Care
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• v.12 no.1
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• pp.20-26
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• 2009

Purpose: We undertook this study to find out the recognitions of terminal cancer patients and doctors about advance directives (ADs), of how they would do in non-response medical conditions and whether ADs could be one of medical options for their dying with dignity. Methods: One hundred thirty four cancer patients in the Hospice Unit, St. Vincent's Hospital, and 97 medical doctors in the Department of Internal Medicine, Catholic Medical Center, were asked about ADs, including Do-Not-Resuscitate (DNR), medical power of attorney, living will and medical options. Results: One hundred thirty patients (97%) and 38 doctors (39.2%) were unfamiliar with ADs, however, 128 patients (95.5%), 95 doctors (97.9%) agreed with it. Seventy nine patients (59.0%) and 96 doctors (99.0%) wanted DNR rather then intensive treatments if they were in non-response medical conditions. Eighty four patients (62.7%) and 75 doctors (77.3%) were agreeable to medical power of attorney. One hundred Thirty four patients (100.0%) and 94 doctors (96.9%) did not want medical options to be in terminal conditions, and hoped to die in peace. Conclusion: Most of patients did not know about ADs and how to make it. However, they showed positive attitudes about it. If we advertise it properly, it is highly likely that a large number of cancer patients would make their living wills easily by ADs. Nevertheless, many legal and ethical problems have to be solved. Doctors should engage their patients in an ongoing communication about the end-of-life. Therefore, let the patients have opportunities to plan their own deaths.