• Molecules and Cells
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• v.20 no.3
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• pp.315-324
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• 2005

Pain is an unpleasant sensation experienced when tissues are damaged. Thus, pain sensation in some way protects body from imminent threat or injury. Peripheral sensory nerves innervated to peripheral tissues initially respond to multiple forms of noxious or strong stimuli, such as heat, mechanical and chemical stimuli. In response to these stimuli, electrical signals for conducting the nociceptive neural signals through axons are generated. These action potentials are then conveyed to specific areas in the spinal cord and in the brain. Sensory afferent fibers are heterogeneous in many aspects. For example, sensory nerves are classified as $A{\alpha}$, $-{\beta}$, $-{\delta}$ and C-fibers according to their diameter and degree of myelination. It is widely accepted that small sensory fibers tend to respond to vigorous or noxious stimuli and related to nociception. Thus these fibers are specifically called nociceptors. Most of nociceptors respond to noxious mechanical stimuli and heat. In addition, these sensory fibers also respond to chemical stimuli [Davis et al. (1993)] such as capsaicin. Thus, nociceptors are considered polymodal. Recent advance in research on ion channels in sensory neurons reveals molecular mechanisms underlying how various types of stimuli can be transduced to neural signals transmitted to the brain for pain perception. In particular, electrophysiological studies on ion channels characterize biophysical properties of ion channels in sensory neurons. Furthermore, molecular biology leads to identification of genetic structures as well as molecular properties of ion channels in sensory neurons. These ion channels are expressed in axon terminals as well as in cell soma. When these channels are activated, inward currents or outward currents are generated, which will lead to depolarization or hyperpolarization of the membrane causing increased or decreased excitability of sensory neurons. In order to depolarize the membrane of nerve terminals, either inward currents should be generated or outward currents should be inhibited. So far, many cationic channels that are responsible for the excitation of sensory neurons are introduced recently. Activation of these channels in sensory neurons is evidently critical to the generation of nociceptive signals. The main channels responsible for inward membrane currents in nociceptors are voltage-activated sodium and calcium channels, while outward current is carried mainly by potassium ions. In addition, activation of non-selective cation channels is also responsible for the excitation of sensory neurons. Thus, excitability of neurons can be controlled by regulating expression or by modulating activity of these channels.

• The Journal of Korean Medicine
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• v.23 no.1
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• pp.37-49
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• 2002

Objectives: Maekmoondong-tang and Jeongcheonhwadamgangki-tang are herbal decoctions which have been used as traditional therapeutic agents for asthma. This study was performed to investigate the effects of Maekmoondong-tang and Jeongcheonhwadamgangki-tang on immune Cell & serum OA-specific 19B in broncho-alveolar lavage fluid (BALF) in rat asthma model. Methods: Rats were sensitized with ovalbumin (OA); at day I the sensitized group and Maekmoondong-tang and Jeongcheonhwadamgangki-tang groups were systemically immunized by subcutaneous injection of 1mg OA and 300mg of $Al(OH)_3$ in a total volume of 2ml. At the same time, 1ml of 0.9% saline containing $6{\times}10^9$ B. pertussis bacilli was injected by i.p. for 14 days. After systemic immunization, the rats received local immunization by inhaling 0.9% saline aerosol containing 2% (wt/vol) OA. A day after local immunization, BAL fluid was collected from the rats. A day after local immunization, rats were orally administered with each of Maekmoondong-tang and Jeongcheonhwadamgangki-tang extract for 14 days. Lymphocyte, CD4+T-cell CD8+ T-cell counts, CD4+/CD8+ ratio in BALF, change of serum OA-specific IgE level, and CD4+T-cell CD8+T-cell percentage in the peripheral blood were measured and evaluated. Results: Maekmoondong-tang and Jeongcheonhwadamgangki-tang showed a suppressive effect on the rat asthma model. Maekmoondong-tang decreased total cell, lymphocyte, CD4+T-cell, CD8+T-cell in BALF, and serum OA specific 19B level as compared with the control group, whereas Maekmoondong-tang decreased CD4+/CD8+ ratio in BALF with statistical nonsignificance as compared with the control group. 1 decreased total cell, CD4+T-cell, CD4+/CD8+ ratio in BALF, and serum OA specific IgE level, whereas Jeongcheonhwadamgangki-tang decreased ymphocyte, and CD8+T-cell in BALF with statistical nonsignificance as compared with the control group. CD4+T-cell and CD8+ T-cell percentage in peripheral blood were not changed significantly in all the experimental groups. Conclusions: This study shows that Maekmoondong-tang and Jeongcheonhwadamgangki-tang have a suppressive effect on asthma. Maekmooruiong-tang and Jeongcheonhwadamgangki-tang would be useful asthma treatment agents.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 1994.10b
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• pp.15-15
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• 1994

M MA ODS 합금의 보다 폭넓용 실용확훌 위해 크게 요구되고 있는 적정 접합기술 개발의 한 방안￡로, 마찰압접(Friction Welding) 방법의 가능성옳 조사하기 위하여 마찰압력과 시간, 마 찰 후 접촉압력(Upset Pressure) 풍을 다양하게 변화시켜 접합체톨 제조한 후, 접합체 강도에 대한 인장시험과 접합계연의 결합 및 미세구조에 대한 현미경 관찰, EDS에 의한 원소분석, 접 합이옴부의 경도분포와 파단면 분석 풍율 행하였다. 실험에 사용된 모재는 기계적 합금법으로 제조된 Inca사의 Ni기 MA 754 합금이었으며, 직경 l 10 mm, 길이 50 mm로 가공한 후, 아세통￡로 초음파 세척하여 접합에 사용하였다. 접합온 브 레이크식 마찰압접기틀 사용하여 행하였으며, 회전시험편의 회전수는 2400 rpm이었A며, 다른 한쪽의 고정시험편과의 마찰압력 및 마찰시간온 각각 50 - 500 MPa과 1-5초로, 또한 업셋압 력도 50 - 600 MPa로 변화시켰다. 이때 업셋압력은 모든 시편에 대해 일정하게 6초동안 가하 였다. 얻어진 접합체는 각 압접조건 당 2개 이상의 접합시험편에 대해 상온 인장강도톨 측정하 였으며, 파단이 일어난 위치를 확인한 후 파면에 대한 분석율 주사전자현미경(SEM)과 에너지 분산형 분광분석기mDS)릎 사용하여 행하였다. 컵합이옴부의 첩합성올 확인하기 위하여, 접합 체를 접합변에 수직으로 절단, 연마한 후 광학현미경과 SEM, EDS 퉁으로 관찰, 분석하여 접 합부의 형상과 결합형성 여부, 접합계면의 미세조직 퉁옳 조사하였다. 또한 마찰압접에 따론 모재와 접합계연부의 경도분포훌 접합이옴부로부터 모재쪽으로 일정 간격율 두어 마이크로 비 커스 경도기로 측정, 조사하였다. 이상의 설험 결과, 다옴과 같온 결론옳 얻었다. ( (1) 접합체 강도가 모채 강도의 95% 이상이 되는 양호한 렵합체흩 얻기 위한 마찰압력 조건 온, 2400 rpm의 회전속도와 6초의 업셋압력 유지시간에서 마찰압력과 업셋압력, 그리고 마찰시 간이 각각 400 MPa 이상과 500 MPa 이상,2초입율 확인하였다. ( (2) 컵합이옴부의 관찰 결과, 모든 마찰압접 조건에서 컵합이옴부는, 기폰 모재의 texture 조직 을 유지하고 있는 모재부 영역(영역 ill)과 첩합계면부에 인접하여 업셋압력이 주어질 때 단조 효과에 의해 계연 외부로 metal flow가 일어나면서 형성된 영역 II, 매우 미세한 결정립으로 구성된 중앙부의 영역 1 로 이투어져 있옴융 확인하였다. ( (3) 최적접합조건이 충족되지 않온 경우, 접합부의 영역 I 에서 관찰된 void와 균열, 불균일한 접합계면 통의 접합결함에 Al과 Y. Ti 퉁￡로 구성된 산화물률이 용집되어 있옴을 확인하였 다-( (4) 접합체의 파단 양상온 크게 접합부 파단과 모재부 파단, 이률의 혼합형 파단i로 나눌수 있었다. 모재부 파단의 경우, 파단면이 매끄럽고 파변상의 결정립도 매우 미세하였으며, 산확물 의 용집도 찾아보기 어려웠 나, 접합부 파단의 경우에는 파변의 굴곡이 비교척 심하고 연성 입계파괴의 형태를 보였￡며, 결정립도 모채부 파단의 경우에 비해 조대하였다. 조대하였다.

• The Korean Journal of Pharmacology
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• v.11 no.1 s.17
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• pp.47-53
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• 1975

The metabolism of many drugs and also of steroid hormones is mediated by enzymes located in the microsomal fraction in smooth surfaced endoplasmic reticulum of mammalian liver. The duration and intensity of action of many drugs are largely determined by the speed at which they are metabolized in the body. Repeated administration of phenobarbital results in the induction of enzymes that metabolize a number of drugs. Lee et al. reported that daily administration of phenobarbital in rats significantly increased the activities of amylase in the pancreatobiliary juice, but the concentration of cholate in the bile was significantly lower in the treated group than that in the control group. After animals were treated with $CCl_4$, histological changes were shown in the endoplasmic reticulum, decreased microsomal enzyme activity and decreased hepatic protein synthesis were apparent. The purpose of the present report was to study the interaction between a 'microsomal-stimulating' agent such as phenobarbital and a 'microsomal- depressing' agent such as $CCl_4$ on hepatic and pancreatic functions in rats. The results obtained are summarized as follows: 1. The mortality rate of $CCl_4$ treated group was 34% and was decreased this figure to 15% with phenobarbital pretreatment. 2. In animals treated with phenobarbital the volume of biliary-pancreatic secretion was markedly elevated but the volume was decreased significantly in animals treated with $CCl_4$. 3. Total bilirubin output was elevated markedly in the $CCl_4$ treated group of rats pretreated with phenobarbital. The bilirubin concentration was increased in $CCl_4$ treated group and decreased in the group treated phenobarbital alone. 4. The concentration and total output of cholate in the bile were significantly lower in the all experimental group than control group. 5. In the animals treated with phenobarbital alone and phenobarbital plus $CCl_4$, the activity of lipase in pancreatobiliary juice was elevated, while in the animals treated with $CCl_4$ alone no change was observed. 6. The activity of amylase in the pancreatobiliary juice was decreased in the $CCl_4$ treated group, but elevated markedly in phenobarbital group and also elevated in phenobarbital-$CCl_4$ group. By the above results, it is concluded, when the liver was damaged by $CCl_4$, the exocrine function of pancreas and liver was decreased simultaneously. However, in the animals pretreated with phenobarbital, the toxicity of $CCl_4$ on the liver and pancreas was reduced.

• Environmental Engineering Research
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• v.25 no.3
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• pp.299-308
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• 2020

Composting is among the most effective integrated waste management strategies used to recycle sewage sludge (SS) waste and generate a useful product. An encapsulated lifting system is a relatively new industrial-scale composting technology. The objective of this study was to evaluate the effectiveness of composting dewatered stabilized SS mixed with green waste using this new technology. The composting process was monitored by changes in the physico-chemical properties, UV-visible spectra, and fourier transform infrared (FTIR) spectra. The composting temperature was steady in the thermophilic range for 24 and 12 d in the intensive and maturation phases, respectively, which fulfilled the disinfection requirement. Moreover, the temperature increased rapidly to 76.8℃ within three days, and the thermophilic temperatures peaked twice and lasted longer than in traditional composting, which accelerated SS degradation and decreased the composting period necessary to obtain mature compost. FTIR spectroscopic analysis showed a diminished in methyl group derived from methylene C-H aliphatic groups because of organic matter degradation by microorganisms and an increased number of aromatic chains. The new technology may be a viable and sustainable alternative for SS management that converts waste into compost that is useful as a soil amendment.

• Journal of Korean Public Health Nursing
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• v.16 no.1
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• pp.95-104
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• 2002

Purpose : This study was conducted to investigate the extent to which the professional self concept between the psychiatric mental health nurse practitioner (PMHNP) and general nurse in psychiatric ward was comparable. The results were expected to provide basic data for developing the construct of professional self concept and making awareness of the importance of the program increasing professional self concept. Method : The subjects of this study were 227 PMHNP and 436 general nurse in psychiatric ward. The instruments used for this study were PSCNI by Arthur (1990), PSI by Heppner and Peterson(1982) and the index of work satisfaction by Slavitt et al.(1978). With the aid of the SAS, t-test. two-way ANOVA and stepwise multiple regression were conducted. Result : 1. The average item score of PSCNI of PMHNP was $2.82\pm0.27$. and that of general nurse was $2.66\pm0.27$. Statistically significant difference between two groups was found(p=0.0000) 2. There was statistically significant difference between two groups in the score of professional practice(p=0.0000), satisfaction(p=0.0024), leadersbip(p=0.0000) , flexibility(p=0.0000) and skill (p=0.0000). 3. Statistically significant differences between the two groups were observed in terms of age(p=0.0003), marital status(p=0.0001). education(p=0.0005), religion(p=-.0144), motive (P=-.0001), length of service as a nurse(p=0.0121), the length of service in psychiatric unit(p=0.0143). However there were no significant interaction effect with group and age, marital state. education, religion, motive, length of service as a nurse, length of service in psychiatric unit. 4. Job satisfaction (JS) and problem solving inventory score(PS) were found to be the highest factor predicting the professional self concept between the PMHNP and general nurse. JS and PS accounted for $43.4\%$ in the professional self concept of PMHNP, whereas PS, JS, age and religion accounted for $53\%$ in the professional self concept of general nurse in psychiatric ward. In conclusion, this study suggested that we need to develop programs and polices to increase the professional self concept of nurse, particularly of psychiatric mental health nurse practitioners.

• Korean Journal of Childcare and Education
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• v.3 no.2
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• pp.22-47
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• 2007

The purpose of this study was to examine whether parental beliefs, value of children, and filial obligation were related. The subjects were 748 students(male 323, female 425) who were currently enrolled at university located in Seoul. The instruments used for this study were Filial Obligation Scale(Cho, 2002), Parenting Beliefs Questionnaire, and Value of Children by Arnold et al.(1975, 2001). Data were analyzed using descriptive statistics, t-test, ANOVA, and Pearson's correlations by SPSS PC Program. The results showed that university students generally demonstrated a higher level of individual-oriented beliefs than relation-oriented beliefs on parental beliefs. With regard to parental beliefs, family relation-oriented beliefs was relatively low in comparison with independence/autonomy-oriented beliefs, happiness-oriented beliefs, and cognition/knowledge-oriented beliefs. In addition, emotional value of children was relatively high in comparison with instrumental value of children. Also, male university students possessed a higher level of filial obligation. the level of cohabitation experience with their parents played a significant role in affecting the level of filial obligation. Unsurprisingly, a higher relation-oriented parental beliefs and emotional value of children demonstrated a higher level of filial obligation. There were also positive relationships between emotional value, instrumental value, and filial obligation. Hence, this study suggests that a practical, functional training services and resources for future parents must be ensued.

• Journal of the Korean earth science society
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• v.24 no.4
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• pp.303-314
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• 2003

Ocean-air observation using an Automatic Weather Station (AWS) and Conductivity Temperature Depth (CTD) was conducted in the Mid-Yellow Sea off Korea during 8-10 July 2002. A water mass lower than 17$^{\circ}C$ around the Taean peninsula and a tidal front between 36$^{\circ}$20'N and 36$^{\circ}$30'N were observed. The horizontal distribution of air temperature was similar to that of sea surface temperature (SST). Hourly observation around Dukjuk island showed the cold and saline southwesterly and the warm and fresh northeasterly in phase with tidal current. Sea fogs two times formed at 2300 LST 8-0130 LST 9, and 0300-0600 LST 9 July 2002 during the observation period, respectively. During the initial stage of fogs, winds became northeasterly at the speed of 2-4m/s$^{-1}$, and air temperature dropped to 18$^{\circ}C$, as the North Pacific High weakened. The satellite image indicated that sea fogs formed over warm water in the western Yellow Sea and moved eastward toward the observation site, which could be called a steam fog. The fogs dissipated when wind speed and air temperature increased.

• The Journal of Korean Academy of Prosthodontics
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• v.39 no.1
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• pp.58-70
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• 2001

For the successful treatment of complete denture, obtaining a good retention is essential. There are lots of factors affecting denture retention. Denture material, one of those factors affecting denture retention, was the subject of this study, and internal surface treatment also considered for the method of enhancing denture retention. Two resin(Lucitone $199^{(R)}$(heat cured resin) Vertex $CP^{(R)}$(self cured resin)) and two metal($Biosil^{(R)}$(Co-Cr alloy), $Vitallium^{(R)}$(Co-Cr alloy)) denture base materials were used for making test denture base. Newly developed device was used for measuring denture retention. After the retention was measured. We treated internal surface of test denture base with $50{\mu}m\;Al_2O_3$ powder, under 90psi, for 1 minute. Then the retention was measured again. The result was analyzed with K-S test, one-way ANOVA test and independent t-test to deter mine the significant differences as the 95% level of confidence. The results are as follows : In cases of without internal surface treatment, the retention was increased in order of $Vitallium^{(R)},\;Biosil^{(R)},\;Vertex CP^{(R)}$ and Lucitone $199^{(R)}$. Except between Vertex $CP^{(R)}$ and $Biosil^{(R)}$, retention of the other materials was significantly different (p<0.05). After the treatment of internal surface, the retention was increased in order of $Vitallium^{(R)},\;Biosil^{(R)},\;Lucno\;199^{(R)},\;Vertex\;CP^{(R)}$. Except between Lucitone $199^{(R)}$ and Vertex $CP^{(R)}$, $Vitallium^{(R)}$ and $Biosil^{(R)}$ the retention of remaining groups was significantly different each other (p<0.05). In the matter of each material, after the internal surface treatment the retention was increased with Vertex $CP^{(R)},\;Biosil^{(R)}\;and\;Vitallium^{(R)}$ and the value of differences were statistically significant. When we compare the retention of resin and metal denture base, the retention of both denture bases increased significantly with internal surface treatment, and resin denture base showed better retention. As the results show, selecting denture base material could be an important choice of complete denture treatment. To increase denture retention, internal surface treatment can be considered as a possible method.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.4
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• pp.377-383
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• 2013

This study examined the radiopacity of eight contemporary luting cements by direct digital radiography. Five disc-shaped specimens ($5mm{\times}1mm$) were prepared for each material tested (BisCem, Clearfil SA Luting, Duolink, Maxcem Elite, Multilink Speed, Panavia F 2.0, RelyX Unicem Clicker, V-link). The specimens were radiographed using a Kodak CS 7600 image plate (Carestream Health, Inc., Rochester, NY, USA) and an aluminum step wedge with a range of thicknesses (1.5 to 16.5 mm in 1.5 mm increments) and a 1 mm tooth used as a reference. A dental X-ray machine Kodak 2200 Intraoral X-ray System (Carestream Health, Inc., Rochester, NY, USA), operating at 70 kVp, 4 mA, 0.156 s and a source-to-sample distance of 30 cm, was used. According to international standards, the radiopacity of the specimens was compared with that of an aluminum step wedge using NIH ImageJ software (available at http://rsb.info.nih.gov/ij/).The data was analyzed by ANOVA and a Tukey's post hoc test. Maxcem Elite (5.66) showed the highest radiopacity of all materials, followed in order by Multilink Speed (3.87) and V-link (2.83). The radiopacity of Clearfil SA Luting (1.35), BisCem (1.33), Panavia F 2.0 (1.29) and Duolink (1.10) were between enamel (1.79) and dentin (0.19). RelyX Unicem Clicker (0.71) showed the lowest radiopacity, which was higher than that of dentin. All materials showed a radiopacity above the minimum recommended by the International Organization for Standardization and the American National Standards/American Dental Association with the exception of RelyX Unicem Clicker.