• Title/Summary/Keyword: Stepwise regression

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The Relationship between Noise Exposure Level in Worksite and Workers' Stress Symptoms (산업장의 소음폭로수준과 근로자의 스트레스 증상간의 관련성)

  • Park, Kyung-Ok;Lee, Myung-Sun
    • Journal of Preventive Medicine and Public Health
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    • v.29 no.2 s.53
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    • pp.239-254
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    • 1996
  • Health services on industrial noisy environment have been provided only for noise-induced hearing loss management until now. But gradually, modem diseases and death have come to be related to stress and mental health deeply, therefore noise-induced mental disorder, like a stress became very important. In this point, the purpose of this study was to analyze the relationship between noise exposure level in worksite and workers' stress symptoms. This study included a survey of 786 manual workers selected from 89 worksites in 21 factories in Puchon. The results were as follows: 1. For demographic characteristics, most of the workers were males(80.8%), the $20\sim29years$ old were 34.5% and those who graduated from high school were 65.3%. The workers whose monthly income ranged from 100,000 to 800,000 won were 37.5% and who have a religion were 47.9%. 2. For occupational characteristics, workers who had worked $1\sim5$ years in the factories were 33.0%. Those who were much for them workload were 43.9% and who worked more than 8 hours a day were 73.9%. Those who were disatisfied with their job and pay were 31.9% and 50.6%. The workers who responsed ventilation condition of their worksites were bad were 51.9% and the dissatisfed with working environment of their worksites were 45.9%. 3. Workers who were suffering from tinnitus were 53.3% and those who perceived hearing loss were 50.1%. Persons who reported they always wore earplugs at work were 35.4%. Those who felt earplugs bigger than their ears were 30.6% and those who experienced eardiseases caused by earplugs were 25.6%. 4. For the noise exposure level in worksite, workers who were exposed to $80\sim90dB$ were 30.3%, $90\sim100dB$ were 26.4% and $50\sim70dB$ were 19.2%. 5. Workers' stress symptoms were significantly related to marital status and their monthly income(p<0.05). Workers who were single and had lower monthly income showed higher PSI (Psychiatric Symptom Index) scores than those who were married and had higher monthly income. Higher PSI scores were also significantly related to $1\sim2$ days hight-work per week, much for them workload, dissatisfaction with their job, and bad relationship with their bosses and coworkers. 6. Higher PSI scores were significantly related to severe tinnitus and perceived hearing losso(p<0.001). Workers who felt the earplugs they use did not fit their ears showed significantly higher PSI scores(p<0.01). Workers who reported that they did not feel they need earplugs showed. significantly higher PSI scores (p<0.05). Increased experience of eardisease caused by earplugs that did not fit were also significantly related to higher PSI scores(p<0.01). 7. The higher noise exposure level in worksite from 80dB was, the more severe stress symptoms including PSI subparts were reported; Anxiety, Anger, Depression, and Cognitive disorder(p<0.001). 5. According to the results of stepwise multiple regression analysis, factors affecting workers' PSI scores were perceived hearing loss$(R^2=0.160)$, noise exposure level in worksite$(R^2=0.110)$, realtionship with coworkers, amount of workload, monthly income and relationship with bosses orderly and the total $R^2$ of this 6 factors was 0.371. 9. The most significant factors that have impact on manual workers' stress symptoms were perceived hearing loss and noise exposure level in worksite, especially noise exposure level in the worksite was the most affective factor on the depression symptom.

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GnRH Agonist Stimulation Test (GAST) for Prediction of Ovarian Response in Controlled Ovarian Stimulation (COH) (난소기능평가를 위한 Gonadotropin Releasing Hormone Agonist Stimulation Test (GAST)의 효용성에 관한 연구)

  • Kim, Mee-Ran;Song, In-Ok;Yeon, Hye-Jeong;Choi, Bum-Chae;Paik, Eun-Chan;Koong, Mi-Kyoung;Song, Il-Pyo;Lee, Jin-Woo;Kang, Inn-Soo
    • Clinical and Experimental Reproductive Medicine
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    • v.26 no.2
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    • pp.163-170
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    • 1999
  • Objectives: The aims of this study are 1) to determine if GAST is a better indicator in predicting ovarian response to COH compared with patient's age or basal FSH level and 2) to evaluate its role in detecting abnormal ovarian response. Design: Prospective study in 118 patients undergoing IVF-ET using GnRH-a short protocol during May-September 1995. Materials and Methods: After blood sampling for basal FSH and estradiol $(E_2)$ on cycle day two, 0.5ml (0.525mg) GnRH agonist ($Suprefact^{(r)}$, Hoechst) was injected subcutaneously. Serum $E_2$ was measured 24 hours later. Initial $E_2$ difference $({\Delta}E_2)$ was defined as the change in $E_2$ on day 3 over the baseline day 2 value. Sixteen patients with ovarian cyst or single ovary or incorrect blood collection time were excluded from the analysis. The patients were divided into three groups by ${\Delta}E_2$; group A (n=30):${\Delta}E_2$<40 pg/ml, group B (n=52): 40 pg/ml${\leq}{\Delta}E_2$<100 pg/ml, group C (n=20): ${\Delta}E_2{\leq}100$ pg/ml. COH was done by GnRH agonist/HMG/hCG and IVF-ET was followed. Ratio of $E_2$ on day of hCG injection over the number of ampules of gonadotropins used ($E_2hCGday$/Amp) was regarded as ovarian responsiveness. Poor ovarian response and overstimulation were defined as $E_2$ hCGday less than 600 pg/ml and greater than 5000 pg/ml, respectively. Results: Mean age $({\pm}SEM)$ in group A, B and C were $33.7{\pm}0.8^*,\;31.5{\pm}0.6\;and\;30.6{\pm}0.5^*$, respectively ($^*$: p<0.05). Mean basal FSH level of group $A(11.1{\pm}1.1mlU/ml)$ was significantly higher than those of $B(7.4{\pm}0.2mIU/ml)$ and C $(6.8{\pm}0.4mIU/ml)$ (p<0.001). Mean $E_2hCGday$ of group A was significantly lower than those of group B or C, i.e., $1402.1{\pm}187.7pg/ml,\;3153.2{\pm}240.0pg/ml,\;4078.8{\pm}306.4pg/ml$ respectively (p<0.0001). The number of ampules of gonadotropins used in group A was significantly greater than those in group B or C: $38.6{\pm}2.3,\;24.2{\pm}1.1\;and\;18.5{\pm}1.0$ (p<0.0001). The number of oocytes retrieved in group A was significantly smaller than those in group B or C: $6.4{\pm}1.1,\;15.5{\pm}1.1\;and\;18.6{\pm}1.6$, respectively (p<0.0001). By stepwise multiple regression, only ${\Delta}E_2$ showed a significant correlation (r=0.68, p<0.0001) with $E_2HCGday$/Amp, while age or basal FSH level were not significant. Likewise, only ${\Delta}E_2$ correlated significantly with the number of oocytes retrieved (r=0.57, p<0.001). All four patients whose COH was canceled due to poor ovarian response belonged to group A only (Fisher's exact test, p<0.01). Whereas none of 30 patients in group A (0%) had overstimulation, 14 patients among 72 patients (19.4%) in group B and C had overstimulation (Fisher's exact test, p<0.01). Conclusions: These data suggest that initial $E_2$ difference after GAST may be a better prognostic indicator of ovarian response to COH than age or basal FSH level. Since initial $E_2$ difference demonstrates significant association with abnormal ovarian response such as poor ovarian response necessitating cycle cancellation or overstimulation, GAST may be helpful in monitoring and consultation of patients during COH in IVF-ET cycle.

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Study of Utilization of Dental High School and according to the Pain Experienced Dental Fear (고등학생의 치과이용실태와 통증 경험에 따른 치과공포에 대한 연구)

  • Jun, Bo-Hye;Choi, Young-Suk
    • Journal of dental hygiene science
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    • v.14 no.1
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    • pp.59-66
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    • 2014
  • The purpose of this study was to study of utilization of dental high school and according to the pain experienced dental fear and anxiety. This survey was conducted on 370 high school students in Suwon from November 21 to 23, 2011. A total of 352 questionnaires were collected and analyzed. The collected data was analyzed using the statistical package SPSS 15.0 using frequency, mean and standard deviation analysis, t-test, one-way ANOVA, Duncan's test correlation analysis and Stepwise multiple regression analysis. The results state that students feel fear and anxiety were feeling anesthetic needle ($3.19{\pm}1.43$), seeing anesthetic needle ($3.14{\pm}1.44$). We found that students feel more rear and anxiety from caries treatment than scaling. It influence that having dental fear with past dental pain experienced during dental treatment and also hearing dental treatment of pain from their family and friends. We found out that there are some influencing factors on dental fear and anxiety, gender, oral health condition, smoking, pain experienced during dental treatment. We need to care dental fear and anxiety continuously and have prevention program. We have to try understanding students have dental fear and anxiety. So it's better they have good experience visiting dental clinic. We should develop the system and specially treat well while they have dental treatment with anesthesia and some sharp instruments.

Factors Related to Serum Vitamin C Level in Terminally Ill Cancer Patients (말기암환자에서 혈청 비타민 C 농도와 연관된 인자들)

  • Kim, Hyung Jun;Hwang, In Cheol;Yeom, Chang Hwan;Ahn, Hong Yup;Choi, Youn Seon;Lee, Jae Jun;Lim, Su Hyuk
    • Journal of Hospice and Palliative Care
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    • v.17 no.4
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    • pp.241-247
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    • 2014
  • Purpose: Serum vitamin C is one of the indicators for antioxidant levels in the body and it is lower in cancer patients compared with the healthy population. However, there have been few studies on the levels of serum vitamin C in terminally ill cancer patients and related factors. Methods: We followed 65 terminal cancer patients who were hospitalized in two palliative care units. We collected data of age, sex, cancer type, functional status, clinical symptoms, history of cancer therapy, and various laboratory findings including serum vitamin C level. Patients were categorized into two groups according to the quartile of serum vitamin C level (Q1-3 vs. Q4), which were compared each other. Stepwise multiple logistic regression analysis was used to identify factors related to serum vitamin C levels. Results: The mean serum vitamin C level was $0.44{\mu}g/mL$, and all patients fell into the category of vitamin C deficiency. Univariate analysis showed that The serum vitamin C level was lower in non-lung cancer patients (P=0.041) and febrile patients (P=0.034). Multivariate analysis adjusted for potential confounders such as lung cancer, fever, dysphagia, dyspnea, C reactive protein, and history of chemotherapy demonstrated that odds for low serum vitamin C level was 3.7 for patients receiving chemotherapy (P=0.046) and 7.22 for febrile patients (P=0.02). Conclusion: Vitamin C deficiency was very severe in terminally ill cancer patients, and it was associated with history of chemotherapy and fever.

Relationship of between blood lead level and lead related symptoms in low level lead exposure (저농도 연폭로에서 혈중 연농도와 자각증상과의 관계)

  • Hwang, Kyu-Yoon;Ahn, Jae-Eog;Ahn, Kyu-Dong;Lee, Byung-Kook;Kim, Joung-Soon
    • Journal of Preventive Medicine and Public Health
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    • v.24 no.2 s.34
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    • pp.181-194
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    • 1991
  • This study intended to obtain an useful information on the prevalence of subjective symptoms, and to clarify the interrelationships between blood lead and lead related symptoms in low level lead exposure. The 93 male workers exposed to lead and 56 male nonexposed workers were examined for their blood lead(PBB), Zinc-protoporphy(ZPP), hemoglobin(HB) and personnal history, and completed 15 questionnaires related to symptoms of lead absorption : also measured lead concentration in air (PBA) in the workplace. The results obtained were as follows ; 1. The means of blood lead (PBB), blood ZPP and hemoglobin (HB) among workers exposed to lead were $26.1{\pm}8.8{\mu}g/dl,\;28.3{\pm}26.0{\mu}g/dl$ and $16.2{\pm}1.2g/dl$ : whereas those of nonexposed workers were $18.7{\pm}5.1{\mu}g/dl,\;20.6{\pm}8.7{\mu}g/dl$ and $17.3{\pm}1.1g/dl$. The means of above three indicies between two groups showed significant difference statistically (p<0.05). 2. The means of blood lead (PBB), blood ZPP and hemoglobin of workers exposed .to different lead concentration in air were as follows : When it was below $25{\mu}g/m^3$, the indices were $24.7{\pm}79,\;26.1{\pm}26.8{\mu}g/dl\;and\;16.4{\pm}1.1g/dl$ respectively : These indices were $27.1{\pm}8.5,\;23.9{\pm}10.92{\mu}g/dl\;and\;16.2{\pm}1.3g/dl$ when the lead concentration in air was $25{\sim}50{\mu}g/m^3$ : and they were $3.4{\pm}9.3,\;42.3{\pm}31.3{\mu}g/dl\;and\;15.5{\pm}1.2g/dl$ when the concentration of lead was above $50{\mu}g/m^3$. Although there were statistical difference in blood lead and hemoglobin among three different lead concentration in air, there was no statistical difference of blood ZPP among the three groups with different exposure levels (p>0.05). 3. The most frequent by complained symptom was 'Generalized weakness and fatigue', and fewest symptom was 'Intermittent pains in abdomen' 4. Only two symptoms out of fifteen symptoms checked by themselves revealed significant difference between exposed and nonexposed groups. These were 'Intermittent pains of abdomen' and 'Joint pain or arthralgia' (p<0.05), No positive correlation was found between the levels of blood lead and symptom groups categorized as gastrointestinal, neuromuscular and constitutional symptoms, 5. Blood lead (r=0.3995) and ZPP (r=0.2837) showed statistically significant correlation with mean lead concentration in air, whereas correlations were not demonstrated between blood lead and lead related symptoms or blood ZPP and lead related symptoms. 6. Blood lead (PBB) and ZPP showed association (r=0.2466) and the equation PBB=23.75+0.0842 ZPP was derived. 7. On stepwise multiple regression, using blood lead level as a dependent variable and ZPP, hemoglobin (HB), age, work duration (WD) and symptom prevalence as a independent variables, only ZPP significantly contributed a lot to blood lead level. 8. While the ZPP measurement was found to be a good indicator in evaluating health effect of lead absorption in low level lead exposure, lead related symptoms were not sensitive enough to evaluate of lead absorption in low level exposure.

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A Study on Influencing Factors in Health Promoting Lifestyles of College Students (대학생의 건강증진 생활양식과 관련요인 연구)

  • Park, Mi-Yeong
    • Research in Community and Public Health Nursing
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    • v.5 no.1
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    • pp.81-96
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    • 1994
  • The primary purpose of this study was to identify factors affecting health promoting lifestyles of college students on the basis of Pender's Health Promotion Model. The subjects were 1,159 students of one university in Seoul. These data were collected by self reporting questionnaire from April 19 to May 3, 1993. This study examined health promoting lifestyles, cognitive-percep-tual factors: perceived health status, perceived importance of health, health locus of control, and health conception, and modifying factors: sex, grade, major, residence type, and attendance at a health care course. The instruments used in this study were Health Promoting Lifestyle Profile by Walker et al. (1987), Health Value Scale by Wallston et al. (1976), Health Locus of Control by Wallston et al. (1978), and Health Conception Scale by Laffrey(1986). The data were analyzed by Cronbach's $\alpha$, mean, standard deviation, percentage, t-test, ANOVA, Pearson's Correlation Coefficient, and Stepwise Multiple Regression with SPSS PC+ Program. The results were as follows : 1. The means of health promoting lifestyles revealed total 3.33, self actualization 3.74, health responsibility 2.72, exercise 2.80, nutrition 3.55, interpersonal surpport 3.76, and stress management 2.96. Interpersonal support showed the highest score and health responsibility showed the lowest score. 2. No significant differences between sex, grade, major, and residence type, and health promoting lifestyles Were founded(p>.05). Attendants at a health care course showed a significant higher score than nonattendants (p<.001). Male showed a significant higher score in exercise subscale, female showed significant higher scores in health responsibility, nutrition, interpersonal support, stress management subscales(p<.001), residence type showed a significant difference in nutrition subscale(p<.001). 3. No significant differences between perceived health status and sex, grade, major, residence type, and attendance at a health care course were founded(p>.05). Perceived importance of health showed no differences among sex, grade, major, and residence type(p>.05), showed only in attendance at a health care course (p<.001). Attendants at a health care course showed a significant higher score than nonattendants(p<.001). No significant differences between health conception and sex, grade, major, and residence type were founded (p>.05), only significant difference between health conception and attendance at a health care course was founded(p<.05). Nonattendants showed a significant higher score in clinical health conception, attendants showed a significant higher score in wellbeing health conception(p<.05). 4. A significant positive correlation between health promoting lifestyles and perceived health status was founded(r=.2415, p<.001). A significant positive correlation between health promoting lifestyles and perceived importance of health was founded (r=.1475, p<.001). The health promoting lifestyles revealed significant positive correlations in internal and powerful others locus of control (r=.3187, p<.001: r=.1475, p<.001), but revealed a significant negative correlation in chance locus of control(r=-.997, p<.001). A significant positive correlation between health promoting lifestyles and clinical health conception and wellbeing health conception were founded (r=.1241, p<.001 : r=.3047, p<.001). 5. Perceived health status was the highest factor predicting health promoting lifestyles of college students(R=.3415, $R^2=11.62$). Perceived health' status, perceived improtance of health, internal locus of control, wellbeing health conception, powerful others locus of control accounted for 28.19% in health promoting lifestyle patterns. In conclusion, college students who reported more helath promoting lifestyles evaluated their health positively, perceived importance of health highly, perceived their health as affected by theirselves, powerful others but not by chance or luck, and accepted health as high level wellness rather than merely the absence of illness. Those who attending at a health care course had healthier lifestyle patterns. And attendance at a health care course had significant. correlations in these cognitive-perceptual factors. Further studies are required to identify reasons of attending a health care course, and to compare health promoting lifestyles pre-post attending a course related to health care.

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Factors Influencing the Meaning of Life for Middle-aged Women (중년여성의 삶의 의미와 영향요인)

  • Park, Geum-Ja
    • Women's Health Nursing
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    • v.8 no.2
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    • pp.232-243
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    • 2002
  • The purpose of this study was to examine factors influencing the meaning of life for middle-aged women. The subjects for the study were 190 middle-aged women who live in Busan. Data were collected from May 25 to June 20, 1999. The instruments for this study were as follows : the meaning of life scale developed by Jung D. R(1978) ; the self-esteem scale developed by Ro, E. Y, Kwon, J. H.(1997) ; the volunteer activity scale developed by Park G. J.(1999), the marital satisfaction scale developed by Choi G. Y.(1999) ; and the health status scale developed by Kim S. Y. (1991). SPSS PC+ was utilized for data analysis. Data were analysed according to frequency and percentage, mean and standard deviation, t-test, ANOVA, Sheffe' s test and Pearson' s correlation coefficients and stepwise multiple regression. The reliability of the tools was tested by Cronbach's $\alpha$ : and it showed reliability scores of 0.88(for the meaning of life tool), 0.81(for the self-esteem tool), 0.94(for the marital satisfaction tool) and 0.78(for the health status tool). The results were as follows: 1) The scores showed that middle-aged women had a moderate level of meaning of life, with a mean of 30.31 and standard deviation of 6.24 (with values ranging from 12.00 to 48.00). The scores showed that middle-aged women had a moderate levels of self-esteem, with a mean of 28.92 and standard deviation of 4.67 (with values ranging from 10.00 to 40.00). The scores showed that middle-aged women had a very low level of volunteer activity, with a mean of 0.87 and standard deviation of 0.93(with values ranging from 0.00 to 1.00). The scores showed that middle-aged women had a moderate level of satisfaction in their marriages, with a mean of 31.99 and standard deviation of 7.84(with values ranging from 12.00 to 48.00). The scores showed that middle-aged women had a moderate level of health status, with a mean of 6.63 and standard deviation of 1.57(with values ranging from 3.00 to 9.00). 2) There was a statistically significant difference of the meaning of life of middle-aged women according to their religion(F=8.930, p=.000), christian ($31.94{\pm}5.96$) had more meaning th life than buddhists ($28.40{\pm}6.23$). 3) There was a statistically significant correlations between the subject' s self-esteem and the her meaning of life(r=0.477, p=0.000), the subject' s level of volunteer activity and meaning of life(r=.428, p=.000), her level of marital satisfaction and meaning of life(r=.417, p=.000), and her level of health status and meaning of life(r=.261, p=.000) among these middle-aged women. 4) Self- esteem was the highest factor influencing the level of meaning of life in middle-aged women. 40.0% of the total variance of levels of meaning of life by was dependent on self-esteem, volunteer activity, marital satisfaction and health status. In conclusion, the higher the self-esteem and levels of volunteer activity, marital satisfaction, and health status of middle-aged women, the higher the meaning of life for them. Therefore, it is necessary to elevate levels of the self-esteem and volunteer activity, marital satisfaction and health status in order to help middle-aged women have more meaning of life.

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Predictive Factors of Hope in Patients with Cancer (암환자의 희망 예측요인)

  • Lee, Hwa Jin;Sohn, Sue Kyung
    • Korean Journal of Adult Nursing
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    • v.12 no.2
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    • pp.184-195
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    • 2000
  • It has been believed that cancer is an omnious factor threatening the future and life itself. Patients having the disease experience anxiety, fear, feeling of weakness, depression and feelings of uncertainty and hopelessness. Most cancer patients, however, have expectations of possible recovery and a better future, very different from the patients who feel hopeless. Therefore. hope allows people to respond effectively to the fatal disease they have and prevents them from detoriorating physically and spiritually, positively influencing their survival, response to treatment and sense of security. Studies previously performed showed that hope is positively correlated with social and family supports, self-esteem, spiritual well-being, responsive action, health promotion behavior and quality of life. Thus, the study attempted to provide basic information on nursing cancer patients by investigating their levels of hope and determining predictive factors which influence hope. For the study 200 cancer patients in two university hospitals located in Pusan were sampled as subjects. Data were collected for twenty nine days from Feburary 1, 1999 to March 1. Instrumets for the study included 10 items from the self-esteem scale by Rosenberg (1965), 39 hope measurements by Kim and Lee(1965), 16 of the social support scale by Tae(1986) and 16 of the general characteristics scale, all of which totaled 81 items. The data were analyzed using the SPSS program. General characteristics of the investigated based on numbers and percentage. Hope, self-esteem and social support were analyzed using means, minimum, maximum and standard deviation. Relations among the foregoing three factors were analyzed using Pearson' correlation coefficient. Levels of hope in cancer patients were determined using t-test, ANOVA and Scheffe test. Predictive factors influencing hope were investigated using multiple stepwise regression analysis. Results of the study are summarized as follows: 1. An average level of hope was $185.55{\pm}23.39$ points(96 min. and 234 max.) 2. Levels of hope showed a significant difference among them according to sex (t=-3.69, P=.000), age(F=4.714, P=.000), job(F=3.247, P=.008), monthly income (F=6.113, P=.003), treatment charge (F=3.796, P=.011), supportive resources (F=10.554, P=.000), diagnosis(F=2.287, P=.029), perceived health status(F=22.184, P=.000), level of pain(F=3.334, P=.021), religion (F=4.911, P=.001) and religion's effect in life (F=11.706, P=.000), 3. For the subjects, self-esteem and social support were $38.32{\pm}7.21$(13 min, and 50 max.) and $52.97{\pm}8.49$points(28 min, 80 max.). Concerning social support, average levels of family support and medical support were found $35.95{\pm}6.05$(18 min, and 40 max) and $27.02{\pm}4.99$ points(20 min and 40 max). The hope the cancer patients showed significant correlations with self-esteem (r=.588, P=.000), family support(r=.224, p=.001) and medical support(r=.221, P=.002). 4. The five variables related to hope (self-esteem, religion's effect in life, perceived health status, social support and age) accounted for 54.2 percent of the hope level; especially, self-esteem was the highest at 34.6%. As shown in the above results, predictive factors which most influence hope in cancer patients were self-esteem and religion's effect of life. Therefore, nursing interventions to increase self-esteem should be developed. Regarding religion's effects, studies on spiritual aspects should be carried out in a way that contributes to promotion of hope.

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Correlation between menton deviation and dental compensation in facial asymmetry using cone-beam CT (Cone-beam CT를 이용한 안면비대칭자에서 이부편위에 따른 치성보상의 양상분석)

  • Park, Soo-Byung;Park, Jeong-Heuy;Jung, Yun-Hoa;Jo, Bong-Hye;Kim, Yong-Il
    • The korean journal of orthodontics
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    • v.39 no.5
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    • pp.300-309
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    • 2009
  • Objective: The purpose of this study was to evaluate the correlation between menton deviation and dental compensation in facial asymmetry. Methods: Tooth axis and distance of first molar and canine to the reference plane were investigated by cone-beam computerized tomography. The subjects consisted of 50 patients with asymmetric mandibles (male 21, female 29, mean age 24.3 years). Control groups were also assessed (male 11, female 9, mean age 25.6 years). Nine measurements (5 linear measurements and 4 angular measurements) were measured in order to evaluate the correlation between menton deviation and the linear and angular difference of first molar and canine in the deviated and none-deviated sides using the defined MPR images. The differences between deviated and non-deviated side, according to menton deviation, were statistically analyzed using stepwise multiple regression analysis. Results: From the result, Menton deviation was negatively correlated with mandibular first molar's angular measurement (${\Delta\angle}LM6$-Mn plane (dev.-ndev.)) and positively with maxillary fist molar's angular measurement (${\Delta\angle}UM6$-FH plane (dev.-ndev.)) (p < 0.01). Two angular measurements (${\Delta\angle}LM6$-Mn plane (dev.-ndev.), ${\Delta\angle}UM6$-FH plane (dev.-ndev.)) explained the variability in menton deviation with a significant $r^2$ value of 0.589. Conclusions: This study suggests that the tooth axis of upper and lower first molars leans towards the deviated side of Menton when there is mandibular asymmetry with Menton deviation.

Variations of Phytoplankton Standing Crops Affecting by Environmental Factors in the Marine Ranching Ground of Tongyeong Coastal Waters from 2000 to 2007 (2000$\sim$2007년 통영바다목장해역에서 환경요인의 영향에 따른 식물플랑크톤 현존량의 변화)

  • Jung, Seung-Won;Kwon, Oh-Youn;Joo, Hyoung-Min;Lee, Jin-Hwan
    • Korean Journal of Environmental Biology
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    • v.25 no.4
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    • pp.303-312
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    • 2007
  • In order to investigate the dynamics of phytoplankton standing crops affecting by environmental factors, biological and environmental factors, this study was examined in the marine ranching ground of Tongyeong coastal waters from 2000 to 2007. During the study, mean water temperature and salinity were 16.7$^{\circ}C$ and 32.9 psu, respectively. pH, DO and SS varied from 7.81$\sim$8.09, 3.02$\sim$8.97 mg $L^{-1}$ and 2.7$\sim$32.2 mg $L^{-1}$, respectively. Mean concentrations of dissolved inorganic nitrogen, phosphate and silicate were 21.75 ${\mu}M$, 0.90 ${\mu}M$ and 14.38 ${\mu}M$, respectively. Chlorophyll a concentrations varied from 0.02 ${\mu}g$ $L^{-1}$ to 25.29 ${\mu}g$ $L^{-1}$ with mean a value of 2.0 ${\mu}g$ $L^{-1}$. These factors did show significant differences on each layer and season, while did not show on the sampling stations. Phytoplankton standing crops varied from $4.21\times10^3$ cells $L^{-1}$ to $1.44\times10^6$ cells $L^{-1}$ with a mean value of $1.92\times10^5$ cells $L^{-1}$. Especially, variations of phytoplankton standing crops had an unimodal pattern as only bloomed in autumn rather than a bimodal pattern as generally bloomed in spring and autumn. In results of stepwise multiple regression analysis, the coefficient of determination $(R^2)$ for total standing crops was 0.35 and the standing crops were affected by water temperature, salinity, phosphate and silicate. The factors affected were different seasonally; water temperature in spring, salinity in summer, water temperature, salinity and silicate in autumn and water temperature, salinity and suspended solids in winter. Therefore, the results from the statistical analysis showed that the environmental factors influencing on the variations of the phytoplankton standing crops were predominantly water temperature and salinity.