• Title/Summary/Keyword: Al(OH)$_3$

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Painful Channels in Sensory Neurons

  • Lee, Yunjong;Lee, Chang-Hun;Oh, Uhtaek
    • 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 Effects of Maekmoondong-tang and Jeongcheonhwadamgangki-tang on Immune Cell and Serum OA-specific IgE in BALF in Rat Asthma Model (맥문동탕과 정천화담항기탕이 알레르기 천식 모델 흰쥐의 BALF내 면역세포 및 혈청 IgE에 미치는 영향)

  • 김진주;정희재;정승기;이형구
    • 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.

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Analysis of a Sea Fog Using Ocean-air Observation Data in the Mid-Yellow Sea off Korea (해양기상 관측자료를 이용한 서해 중부해역 해무 분석)

  • Oh, Hee-Jin;Lee, Ho-Man;Seo, Tae-Gun;Youn, Yong-Hoon;Kim, Tae-Hee
    • 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.

Size and Shape Effect of Metal Oxides on Hydrocarbon Selective Catalytic Reduction of Nitrogen Oxides (금속 산화물 촉매의 크기와 형태에 따른 질소산화물의 탄화수소 선택적 촉매환원 특성)

  • Ihm, Tae-Heon;Jo, Jin-Oh;Hyun, Young Jin;Mok, Young Sun
    • Journal of the Korean Institute of Gas
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    • v.19 no.5
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    • pp.20-28
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    • 2015
  • This work investigated the size and shape effect of ${\gamma}$-alumina-supported metal oxides on the hydrocarbon selective catalytic reduction of nitrogen oxides. Several metal oxides including Ag, Cu and Ru were used as the catalysts, and n-heptane as the reducing agent. For the Ag/${\gamma}$-alumina catalyst, the $NO_x$ reduction efficiency in the range of $250{\sim}400^{\circ}C$ increased as the size of Ag decreased (20 nm>50 nm>80 nm). The shape effect of metal oxides on the $NO_x$ reduction was examined with spherical- and wire-shape nanoparticles. Under identical condition, higher catalytic activity for $NO_x$ reduction was observed with Ag and Cu wires than with the spheres, while spherical- and wire-shape Ru exhibited similar $NO_x$ reduction efficiency to each other. Among the metal oxides examined, the best catalytic activity for $NO_x$ reduction was obtained with Ag wire, showing almost complete $NO_x$ removal at a temperature of $300^{\circ}C$. For Cu and Ru catalysts, considerable amount of NO was oxidized to $NO_2$, rather than reduced to $N_2$, leading to lower $NO_x$ reduction efficiency.

Study for the Stabilization of Arsenic in the Farmland Soil by Using Steel Making Slag and Limestone (제강슬래그와 석회석을 이용한 비소오염 농경지 토양 안정화 연구)

  • Lee, Min-Hee;Jeon, Ji-Hye
    • Economic and Environmental Geology
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    • v.43 no.4
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    • pp.305-314
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    • 2010
  • The stabilization process using limestone ($CaCO_3$) and steel making slag as the immobilization amendments was investigated for As contaminated farmland soils around Chonam abandoned mine, Korea. Batch and continuous column experiments were performed to quantify As-immobilization efficiency in soil and the analyses using XRD and SEM/EDS for secondary minerals precipitated in soil were also conducted to understand the mechanism of Asimmobilization by the amendments. For the batch experiment, with 3% of limestone and steel making slag, leaching concentration of As from the contaminated soil decreased by 62% and 52% respectively, compared to that without the amendment. When the mixed amendment (2% of limestone and 1% of steel making slag) was used, As concentration in the effluent solution decreased by 72%, showing that the mixed of limestone and steel making slag has a great capability to immobilize As in the soil. For the continuous column experiments without the amendment, As concentration from the effluent of the column ranged from 50 to $80\;{\mu}g/L$. However, with 2% limestone and 1% steel making slag, more than 80% diminution of As leaching concentration occurred within 1 year and maintained mostly below $10\;{\mu}g/L$. Results from XRD and SEM/EDS analysis for the secondary minerals created from the reaction of the amendments with $As^{+3}$ (arsenite) investigated that portlandite ($Ca(OH)_2$), calcium-arsenite (Ca-As-O) and calcite ($CaCO_3$) were main secondary minerals and the distinct As peaks in the EDS spectra of the secondary minerals can be observed. These findings suggest that the co-precipitation might be the major mechanisms to immobilize As in the soil medium with limestone and steel making slag.

The effects of Moxibustion Therapy on Chronic Low Back Pain, Daily Living Disability and Sleep Pattern in Elderly Women (뜸요법이 여성노인의 만성요통, 일상생활기능장애 및 수면양상에 미치는 효과)

  • Kim, Hye-Jeong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.7
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    • pp.301-310
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    • 2016
  • This is a nonequivalent control group non-synchronized experiment research to verify the effect of moxibustion therapy on efficient management of daily living disabilities and sleep patterns in elderly women with chronic low back pain. Total 12 sessions of moxibustion therapy were applied to elderly women(30 subjects in an experimental group and 30 subjects in a control group) in G City once a week for 12 weeks from March 15th to May $31^{st}$ 2015. Then the follow-up study was conducted 2 weeks after the post survey. For moxibustion, was applied to Shen-shu, Ashi point, Ta chang shu, Yang kuan and Yosu. 5 sheets of moxibustion were applied to 7 acupuncture points of Mugeukboyang moxibustion; Zu san li & Chu chi, Chung wan, Chung chi & Shui tao, Fei shu, Kao hung and Tien shu, Wijung respectively and experimental treatment was conducted. For assessing the degree of back pain, Visual Analog Scale(VAS) developed by Scott & Huskisson(1979) was used and for measuring the degree of daily living disability, Oswestry Disability Index, which was developed by Fairbank et al(1980) and translated and revised by Yim, Hyeon-sul et al.(1998), was used. For measuring sleep patterns, the sleep pattern measurement tool developed by Oh, Jin-su, Song, Mi-soon and Kim, Sin-mi(1998) was used. For data analysis, SPSS/WIN 18.0 was employed and Chi-square test, t-test and repeated measures ANOVA were performed. There were significant differences in pain score(F=2510.32, p<.001), daily living disability score(F=1937.82, p<.001) and sleep pattern score((F=15.54, p<.001) of elderly women that were provided with moxibustion therapy, compared to the control group. Therefore, it was found that moxibustion therapy made a positive contribution to reduction in pain and daily living disabilities and improvement in sleep quality. Based on this study finding, there is a need to apply moxibustion therapy to elderly people with chronic low back pain as a nursing intervention in future.

Removal of Arsenite by Nanocrystalline Mackinawite(FeS)-Coated Alumina (나노크기 매킨나와이트로 코팅된 알루미나에 의한 아비산염의 제거)

  • Lee, Seungyeol;Kang, Jung Chun;Park, Minji;Yang, Kyounghee;Jeong, Hoon Young
    • Journal of the Mineralogical Society of Korea
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    • v.26 no.2
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    • pp.101-110
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    • 2013
  • Due to the large specific surface area and great reactivity toward environmental contaminants, nanocrystalline mackinawite (FeS) has been widely applied for the remediation of contaminated groundwater and soil. Furthermore, nanocrystalline FeS is rather thermodynamically stable against anoxic corrosion, and its reactivity can be regenerated continuously by the activity of sulfate-reducing bacteria. However, nanocrystalline mackinawite is prone to either spread out along the groundwater flow or cause pore clogging in aquifers by particle aggregation. Accordingly, this mineral should be modified for the application of permeable reactive barriers (PRBs). In this study, coating methods were investigated by which mackinawite nanoparticles were deposited on the surface of alumina or activated alumina. The amount of FeS coating was found to significantly vary with pH, with the highest amount occurring at pH ~6.9 for both minerals. At this pH, the surfaces of mackinawite and alumina (or activated alumina) were oppositely charged, with the resultant electrostatic attraction making the coating highly effective. At this pH, the coating amounts by alumina and activated alumina were 0.038 and 0.114 $mmol{\cdot}FeS/g$, respectively. Under anoxic conditions, arsenite sorption experiments were conducted with uncoated alumina, uncoated activated alumina, and both minerals coated with FeS at the optimal pH for comparison of their reactivity. Uncoated activated alumina showed the higher arsenite removal compared to uncoated alumina. Notably, the arsenite sorption capacity of activated alumina was little changed by the coating with FeS. This might be attributed to the abundance of highly reactive hydroxyl functional groups (${\equiv}$AlOH) on the surface of activated alumina, making the arsenite sorption by the coated FeS unnoticeable. In contrast, the arsenite sorption capacity of alumina was found to increase substantially by the FeS coating. This was due to the consumption of the surface hydroxyl functional groups on the alumina surface and the subsequent occurrence of As(III) sorption by the coated FeS. Alumina, on the surface area basis, has about 8 times higher FeS coating amount and higher As(III) sorption capacity than silica. This study indicates that alumina is a better candidate than silica for the coating of nanocrystalline mackinawite.

Removal of Red Tide Organisms -2. Flocculation of Red Tide Organisms by Using Loess- (적조생물의 구제 -2. 황토에 의한 적조생물의 응집제거-)

  • KIM Sung-Jae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.33 no.5
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    • pp.455-462
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    • 2000
  • The objective of this study was to examine the physicochemical characteristics of coagulation reaction between loess and red tide organisms (RTO) and its feasibility, in developing a technology for the removal of RTO bloom in coastal sea. The physicochemical characteristics of loess were examined for a particle size distribution, surface characteristics by scanning electron microscope, zeta potential, and alkalinity and pH variations in sea water. Two kinds of RTO that were used in this study, Cylindrothen closterium and Skeietonema costatum, were sampled in Masan bay and were cultured in laboratory. Coagulation experiments were conducted using various concentrations of loess, RTO, and a jar tester. The supernatant and RTO culture solution were analyzed for pH, alkalinity, RTO cell number. A negative zeta potential of loess increased with increasing pH at $10^(-3)M$ NaCl solution and had -71.3 mV at pH 9.36. Loess had a positive zeta potential of +1,8 mV at pH 1.98, which resulted in a characteristic of material having an amphoteric surface charge. In NaCl and $CaCl_2$, solutions, loess had a decreasing negative zeta potential with increasing $Na^+\;and\;Ca^(+2)$ ion concentration and then didn't result in a charge reversal due to not occurring specific adsorption for $Na^+$ ion while resulted in a charge reversal due to occurring specific adsorption for $Ca^(+2)$ ion. In sea water, loess and RTO showed the similar zeta potential values of -112,1 and -9.2 mV, respectively and sea sand powder showed the highest zeta potential value of -25.7 mV in the clays. EDLs (electrical double-layers) of loess and RTO were extremely compressed due to high concentration of salts included in sea water, As a result, there didn't almost exist EDL repulsive force between loess and RTO approaching each other and then LVDW (London-yan der Waals) attractive force was always larger than EDL repulsive force to easily form a floe. Removal rates of RTO exponentially increased with increasing a loess concentration. The removal rates steeply increased until $800 mg/l$ of loess, and reached $100{\%}$ at 6,400 mg/l of loess. Removal rates of RTO exponentially increased with increasing a G-value. This indicated that mixing (i.e., collision among particles) was very important for a coagulation reaction. Loess showed the highest RTO removal rates in the clays.

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The Role of Chest CT Scans in the Management of Empyema (농흉에서 전산화 단층촬영의 의의)

  • Heo, Jeong-Suk;Kwun, Oh-Yong;Sohn, Jeong-Ho;Choi, Won-Il;Hwang, Jae-Seok;Han, Seung-Beom;Jeon, Young-June;Kim, Jung-Sik
    • Tuberculosis and Respiratory Diseases
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    • v.41 no.4
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    • pp.397-404
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    • 1994
  • Background: To decide the optimal antibiotics and application of chest tube, examination of pleural fluid is fundamental in the management of empyema. Some criteria for drainage of pleural fluid have been recommended but some controversies have been suggested. Recently, newer radiologic methods including ultrasound and computed tomography scanning, have been applied to the diagnosis and management of pleural effusions. We undertook a retrospective analysis of 30 patients with pleural effusion who had CT scans of the chest in order to apply the criteria of Light et al retrospectively to patients with loculation and to correlate the radiologic appearance of pleural effusions with pleural fluid chemistry. Method: We analyzed the records of 30 out of 147 patients with pleural effusion undergoing chest CT scans. Results: 1) Six of the pleural fluid cultures yielded gram negative organisms and three anaerobic bacterias and one Staphylococcus aureus and one non-hemolytic Streptococci. No organism was cultured in ninteen cases(63.0%). 2) The reasons for taking chest CT scans were to rule out malignancy or parenchymal lung disease(46.7%), poor response to antibiotics(40.0%), hard to aspirate pleural fluid(10.0%) and to decide the site for chest tube insertion(3.3%). 3) There was no significant correlations between ATS stages and loculation but there was a tendency to loculate in stage III. 4) There was a significant inverse relationship between the level of pH and loculation(p<0.05) but there appeared to be no relationship between pleural fluid, LDH, glucose, protein, loculation and pleural thickening. 5) In 12 out of 30, therapeutic measures were changed according to the chest CT scan findings. Conclusion: We were unable to identify any correlations between the plerual fluid chemistry, ATS stages and loculations except pH, and we suggest that tube thoracotomy should be individualized according to the clinical judgement and serial observation. All patients with empyema do not need a chest CT scan but a CT scan can provide determination of loculation, guiding and assessing therapy which should decrease morbidity and hospital stay.

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The Comparative Study on Health Promoting Behaviors by Shift Pattern of Duties of Women Workers in workplace (산업장 여성근로자의 근무형태에 따른 건강증진행위 비교)

  • Jang, Hee Jung;Park, Kyung Min
    • Korean Journal of Occupational Health Nursing
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    • v.8 no.1
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    • pp.22-41
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    • 1999
  • This study intended to analyze the health promoting behaviors, compare their factors according to the shift pattern of duties of women workers who were working in the industrial workplace and present basic data in planning systematic and effective programs of health promotion for three-shift system and day-duty. Using Quota Sampling, 219 women workers were selected as subjects from 5 workshops which had 50 settled workers up to 300 and 10 factories which had more than 300 located in Taegu and Kyung-Book Province. Data were collected by means of questionnaire from September 12 to September 30, 1998. As the instruments of the study were used Health Promotion Lifestyle Profile(HPLP) which was adapted and adjusted by Seo, Y. O. for health promoting behavior, the one developed by Moon, J. S. (1990) for health-belief, the one developed by Sherer et al.(1982) and then adapted by Oh, H. S. for self-efficacy, and the one developed by Park, J. W. (1985) for social support. The analysis of data were performed with Cronbach's ${\chi}^2$-test, t-test, ANCOVA, Kendal tau, Pearson correlation, Stepwise Multiple Regression test using SPSS program. The results of the study are as follows : 1. There was a significant difference in age(${\chi}^2=32.46$, p=0.000), career (${\chi}^2=18.47$, p=0.000), working day(t=-3.18, p=0.000) by the shift pattern of duties in terms of socio-demographic characteristics. 2. There was a statistically significant difference between the two groups on the health promoting behaviors (t=2,52, p=0.012). The score of three-shift group on health promoting behaviors was 2.27, showing that it was lower by .13 than that of day-duty group(2.40). 3. ANCOVA involving age, career and working day as covariables, which had revealed significant difference before, showed that health promoting behaviors by the shift patterns of duties was significantly different(F=4.88, p=0.028). 4. In consideration of variables that have an influence on health promoting behavior by the shift pattern of duties, social support occupied 19.4% of health promoting behavior in the three-shift group and 22.5% including the sense of self-efficacy. In the day-duty group, social support occupied 34.4% of health promoting behavior. 5. The score of three-shift group(2.94) was significantly lower than that of day-duty group(3.12) in the perceived benefit of health-belief(t= -3.29, p=0.001), while the score of three-shift group (2.48) was significantly higher than that of day-duty group(2.24) in the perceived barrier (t=4.22, p=0.000). In the sense of self-efficacy(t=-4.20, p=0.000), the score of three-shift group(3.24) was significantly lower than that of day-duty group(3.53) while in social support(t=-4.56, p=0.000) the one of three-shift group(2.64) was significantly lower than that of day-duty group(2.88). The suggestions are as follows on the basis of the results of this study : 1. It is required to develop health promoting program that takes the shift pattern of duties of women workers into consideration. In addition, there are special demands on developing nursing strategies for health promoting behavior of three-shift workers. 2. It is required to develop specific strategies for social support which is the most significant factor to the health promoting behavior for women workers. 3. It is necessary to develop some programs for improving the sense of self-efficacy, social support, and health-belief of three-shift workers. To achieve these tasks, industrial nurses should play an active role and improve the ability of self-health care of women workers.

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