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A Study of Community Residents' Consciousness of Taking Herb Medicine (지역사회 주민의 한약복용에 대한 의식 조사 연구)

  • Kim Sung-Jin;Nam Chul-Hyun;Kang Young-Woo;Suh Ho-Suk;Jeon Bong-Cheon;Chang Young-Jin
    • Journal of Society of Preventive Korean Medicine
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    • v.6 no.1
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    • pp.15-35
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    • 2002
  • This study was conducted to provide basic data for policy of Oriental medicine by analyzing community resident's consciousness of taking herb medicine and its related factors. Data were collected from 1478 residents from March 2, 2001 to May 31, 2001. The results of this study are summarized as follows. 1) The rate of experience of taking herb medicine was 85.2%(88.2% of 'male'; 82.5% of 'female'). It appeared to be significantly higher in the groups of 'the married', 'housewife', and 'Buddhist'. As the age increased, so the rate of experience of taking herb medicine was significantly high. 2) In case of purpose of taking herb medicine, taking herb medicine as a restorative(66.8%) was much higher than taking it as a curative medicine. 3) 52.1% of the respondents satisfied with the effect of herb medicine. The groups of 'male', 'older age', 'residents in a big city', 'insurant in company', and 'the employed' showed significantly high rate in satisfying with herb medicine than the other groups. 4) According to the reason for preferring herb medicine, 36.7% of the respondents preferred herb medicine because the herb medicine was effective, while 27.8% preferred it because its side effect was low. 16.7% preferred it because persons around them recommended it. 5) 42.6% of the respondents did not want to take the herb medicine because the price of the herb medicine was high. Also 20.6% of the respondents did not want to take herb medicine because it is uneasy to take herb medicine. 15.8% did not want to take it because certain food should not be taken during the period of taking it. 9.4% did not want to take it because it tasted bitter. 6) In case of opinions on side effects of herb medicine, 40.8% of the respondents thinks that herb medicine is free from side effects, while 37.5% thinks that it causes side effects. There were significant difference in the opinions on side effects by sex, age, marital status, resident area, education level, occupation, and type of health insurance. 7) 60.7% of the respondents thinks the price of herb medicine is not resonable, while only 10.9% thinks it is resonable. 8) 45.2% of the respondents uses packs of decocted herbs although they think the packs of decocted herb are a little low effective because decocting herbs in home is bothersome. 45.2% uses packs of decocted herbs because they are convenient, being not related to the effect. 7.6% takes medicinal herbs after decocting them in a clay pot because they think the packs of decocted herbs have low effect. 51.9% does not know whether taking herb medicine in summer is effective or not because the effect is different according to their physical constitutions. 35.5% thinks that taking herb medicine is summer is effective because their physical stamina is weakened after sweated a lot, while 12.6% thinks that it is not effective because the effect of herb medicine disappears with sweat. 9) According to the level of satisfaction with Oriental medical care, the respondents marked $3.47{\pm}0.64$ points on the base of 5 points. It was significantly higher in the groups of 'male', 'the married, resident in a big city', 'highschool graduate', 'the unemployed', 'office clerk', 'growing up in a big city', 'insurant in region', and 'the middle class'. 10) According to the result of a regression analysis of factors influencing preference for herb medicine, the factors displayed significant difference by sex, age, education level, health status, and times of receiving Oriental medical care. As shown in the above results, the community residents satisfy with the effect of herb medicine. Therefore, the method of taking herb medicine without difficulty must be devised. The medicinal herbs in packages need to be included in health insurance coverage and resonable price of herb medicine must be set. Also, education program for community residents must be developed in order to provide right information in herb medicine. Therefore, related public authority, associations, and professionals must make efforts, forming organic cooperative system.

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Study on the Neural Network for Handwritten Hangul Syllabic Character Recognition (수정된 Neocognitron을 사용한 필기체 한글인식)

  • 김은진;백종현
    • Korean Journal of Cognitive Science
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    • v.3 no.1
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    • pp.61-78
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    • 1991
  • This paper descibes the study of application of a modified Neocognitron model with backward path for the recognition of Hangul(Korean) syllabic characters. In this original report, Fukushima demonstrated that Neocognitron can recognize hand written numerical characters of $19{\times}19$ size. This version accepts $61{\times}61$ images of handwritten Hangul syllabic characters or a part thereof with a mouse or with a scanner. It consists of an input layer and 3 pairs of Uc layers. The last Uc layer of this version, recognition layer, consists of 24 planes of $5{\times}5$ cells which tell us the identity of a grapheme receiving attention at one time and its relative position in the input layer respectively. It has been trained 10 simple vowel graphemes and 14 simple consonant graphemes and their spatial features. Some patterns which are not easily trained have been trained more extrensively. The trained nerwork which can classify indivisual graphemes with possible deformation, noise, size variance, transformation or retation wre then used to recongnize Korean syllabic characters using its selective attention mechanism for image segmentation task within a syllabic characters. On initial sample tests on input characters our model could recognize correctly up to 79%of the various test patterns of handwritten Korean syllabic charactes. The results of this study indeed show Neocognitron as a powerful model to reconginze deformed handwritten charavters with big size characters set via segmenting its input images as recognizable parts. The same approach may be applied to the recogition of chinese characters, which are much complex both in its structures and its graphemes. But processing time appears to be the bottleneck before it can be implemented. Special hardware such as neural chip appear to be an essestial prerquisite for the practical use of the model. Further work is required before enabling the model to recognize Korean syllabic characters consisting of complex vowels and complex consonants. Correct recognition of the neighboring area between two simple graphemes would become more critical for this task.

A Study of Community Residents' Consciousness of Taking Herb Medicine (지역사회 주민의 한약복용에 대한 의식 조사 연구)

  • Kim Sung-Jin;Nam Chul-Hyun
    • Journal of Society of Preventive Korean Medicine
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    • v.3 no.2
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    • pp.25-53
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    • 1999
  • This study was conducted to provide basic data for policy of Oriental medicine by analyzing community residents' consciousness of taking herb medicine and its related factors. Data were collected from 1478 residents from March 2, 1999 to May 31, 1999. The results of this study are summarized as follows. 1. According to general characteristics of the subjects, 52.3% of the subjects was 'female'; 25.0% 'fifties of age'; 21.4% 'forties of age'; 20.9% 'thirties of ages'; 69.1% 'married'; 60.1% 'resident in a big city'; 12.1% 'residents in a small town or village'; 39.0% 'highschool graduate'; 35.9% 'above college graduate'; 23.4% 'housewife'; 23.4% 'professional' 34.1% 'Buddhist'; 81.1% 'middle class'. 2. The rate of experience of taking herb medicine was 85.2%(88.2% of 'male'; 82.5% of 'female'). It appeared to be significantly higher in the groups of 'the married', 'housewife', and 'Buddhist'. As the age increased, so the rate of experience of taking herb medicine was significantly high. 3. In case of purpose of taking herb medicine, taking herb medicine as a restorative(66.8%) was much higher than taking it as a curative medicine. Taking herb medicine as a curative medicine appeared to be significantly higher in the groups of 'male', 'thirties of age', 'resident in a town or village', 'above college graduate', 'professional technician', 'Christian', and 'the upper class'. 4. 52.1% of the respondents satisfied with the effect of herb medicine. The groups of 'male', 'older age', 'residents in a big city', 'insurant in company', and 'the employed' showed significantly high rate in satisfying with herb medicine than the other groups. 5. According to the reason for preferring herb medicine, 36.7% of the respondents preferred herb medicine because the herb medicine was effective, while 27.8% preferred it because its side effect was low. 16.7% preferred it. because persons around them recommended it. The preference for the herb medicine displayed significantly higher rate in the groups 'sixties of age', 'the unmarried', 'resident in a big city', 'office clerk', and 'the lower class'. 6. 42.6% of the respondents did not want to take the herb medicine because the price of the herb medicine was high. Also 20.6% of the respondents did not want to take herb medicine because it is uneasy to take herb medicine. 15.8% did not want to take it because certain foods should not be taken during the period of taking it. 9.4% did not want to take it because it tasted bitter. 7. In case of opinions on side effects of herb medicine, 40.8% of the respondents thinks that herb medicine is free from side effects, while 37.5% thinks that it causes side effects. There were significant difference in the opinions on side effects by sex, age, marital status, resident area, education level, occupation, and type of health insurance. 8. 60.7% of the respondents thinks the price of herb medicine is not resonable, while only 10.9% thinks it is resonable. 9. 14.2% of the respondents thinks health foods which contain herbs are good, while 16.8% thinks it is bad. 76.7% thinks that medicinal herbs in packages must be included in health insurance coverage, while only 3.0% thinks it needs not be included in health insurance coverage. 10. 45.2% of the respondents uses packs of decocted herbs although they think the packs of decocted herb are a little low effective because decocting herbs in home is bothersome. 45.2% uses packs of decocted herbs because they are convenient, being not related to the effect. 7.6% takes medicinal herbs after decocting them in a clay pot because they think the packs of decocted herbs have low effect. 11. According to the level of satisfaction with Oriental medical care, the respondents marked $3.47{\pm}0.64$ points on the base of 5 points. It was significantly higher in the groups of 'male', 'the married, resident in a big city', 'highschool graduate', 'the unemployed', 'office clerk', 'growing up in a big city', 'insurant in region', and 'the middle class'. 12. According to the result of a regression analysis of factors influencing preference for herb medicine, the factors displayed significant difference by sex, age, education level, health status, and times of receiving Oriental medical care. As shown in the above results, the community residents satisfy with the effect of herb medicine. Therefore, the method of taking herb medicine without difficulty must be devised. The medicinal herbs in packages need to be included in health insurance coverage and resonable price of herb medicine must be set. Also, education program for community residents must be developed in order to provide right information in herb medicine. Therefore, related public authority, associations, and professionals must make efforts, forming organic cooperative system.

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Structural analysis of the Social Support, Career Capability, Career Decision-making Self-Efficacy and Career Adaptability for the Reemployment Women (재취업여성이 지각한 사회적지지, 진로역량 진로결정자기효능감 및 진로적응성 간의 구조적 관계 분석)

  • Shin, Su-Jeong;Lee, In-Hee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.8
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    • pp.422-432
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    • 2018
  • This study is designed to find out the causal relation between social support, career capability, career decision-making self-efficacy and career adaptability for the career interrupted women. For this purposes the scales of social support, career capability, career decision related self efficacy and career adaptability were used. For this study, the questionnaires were distributed from Mar. 2, 2018 to Apr. 6, 2018 to 960 to the career interrupted women who had the experience of getting training at the vocational school, beauty school and women's centers located in Seoul and Gyeonggi area (composed of married women in their 30s and 50s who were receiving the education of beauty care for more than 1-9 months). 920 questionnaires got responded from the women and they were used for the final analysis with Cronbach's ${\alpha}$, exploratory factor analysis, factor analysis, frequency analysis and correlation analysis performed with SPSS program and the structural equation performed with AMOS program. The findings from the analysis are as follows; First, it was found that the structural model between career capability, social support, career decision related self efficacy and career adaptability are proper. Second, the path coefficient of the structural model was found to be statistically significant with respect to all of career capability, social support, career decision related self efficacy and career adaptability. Third, it was found that in the relation between career capability, social support and career adaptability, the career decision related self efficacy has the mediating effect. These results show that if the level of career adaptability is to be enhanced for the caber interrupted women, the career decision related self efficacy can make the critical role in addition to the career capability and social support. So, this study tries to offer the basic data required for the preparation of career and the development of future career for the success of career interrupted women going back to the workplace.

A basic research for evaluation of a Home Care Nursing Delivery System (가정간호 서비스 질 평가를 위한 도구개발연구)

  • Kim, Mo-Im;Cho, Won-Jung;Kim, Eui-Sook;Kim, Sung-Kyu;Chang, Soon-Bok;Ryu, Ho-Sihn
    • Journal of Korean Academic Society of Home Health Care Nursing
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    • v.6
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    • pp.33-45
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    • 1999
  • The purpose of this study was to develop a basic framework and criteria for evaluation of quality care provided to patients with the attributes of disease in the home care nursing field, and to provide measurement tools for home health care in the future. The study design was a developmental study for evaluation of hospital-based HCN(home care nursing) in Korea. The study process was as follows: a home care nursing study team of College of Nursing. Yonsei University reviewed the nursing records of 47 patients who were enrolled at Yonsei University Medical Center Home Care Center in March, 1995. Twenty-five patients were insured at that time, were selected from 47 patients receiving home care service for study feasibility with six disease groups; Caesarean Section (C/S), simple nephrectomy, Liver cirrhosis(LC), chronic obstructive pulmonary disease(COPD), Lung cancer or cerebrovascular accident(CVA). In this study, the following items were selected : First step : Preliminary study 1. Criteria and items were selected on the basis of related literature on each disease area. 2. Items were identified by home care nurses. 3. A physician in charge reviewed the criteria and content of selected items. 4. Items were revised through preliminary study offered to both HCN patients and discharged patients from the home care center. Second step : Pretest 1. To verify the content of the items, a pretest was conducted with 18 patients of which there were three patients in each of the six selected disease groups. Third step : Test of reliability and validity of tools 1. Using the collected data from 25 patients with either cis, Simple nephrectomy, LC, COPD, Lung cancer, or CVA. the final items were revised through a panel discussion among experts in medical care who were researchers, doctors, or nurses. 2. Reliability and validity of the completed tool were verified with both inpatients and HCN patients in each of field for researches. The study results are as follows: 1. Standard for discharge with HCN referral The referral standard for home care, which included criteria for discharge with HCN referral and criteria leaving the hospital were established. These were developed through content analysis from the results of an open-ended questionnaire to related doctors concerning characteristic for discharge with HCN referral for each of the disease groups. The final criteria was decided by discussion among the researchers. 2. Instrument for measurement of health statusPatient health status was measured pre and post home care by direct observation and interview with an open-ended questionnaire which consisted of 61 items based on Gorden's nursing diagnosis classification. These included seven items on health knowledge and health management, eight items on nutrition and metabolism, three items on elimination, five items on activity and exercise, seven items on perception and cognition, three items on sleep and rest, three items on self-perception, three items on role and interpersonal relations, five items on sexuality and reproduction, five items on coping and stress, four items on value and religion, three items on family. and three items on facilities and environment. 3. Instrument for measurement of self-care The instrument for self-care measurement was classified with scales according to the attributes of the disease. Each scale measured understanding level and practice level by a Yes or No scale. Understanding level was measured by interview but practice level was measured by both observation and interview. Items for self-care measurement included 14 for patients with a CVA, five for women who had a cis, ten for patients with lung cancer, 12 for patients with COPD, five for patients with a simple nephrectomy, and 11 for patients with LC. 4. Record for follow-up management This included (1) OPD visit sheet, (2) ER visit form, (3) complications problem form, (4) readmission sheet. and (5) visit note for others medical centers which included visit date, reason for visit, patient name, caregivers, sex, age, time and cost required for visit, and traffic expenses, that is, there were open-end items that investigated OPD visits, emergency room visits, the problem and solution of complications, readmissions and visits to other medical institution to measure health problems and expenditures during the follow up period. 5. Instrument to measure patients satisfaction The satisfaction measurement instrument by Reisseer(1975) was referred to for the development of a tool to measure patient home care satisfaction. The instrument was an open-ended questionnaire which consisted of 11 domains; treatment, nursing care, information, time consumption, accessibility, rapidity, treatment skill, service relevance, attitude, satisfaction factors, dissatisfaction factors, overall satisfaction about nursing care, and others. In conclusion, Five evaluation instruments were developed for home care nursing. These were (1)standard for discharge with HCN referral. (2)instrument for measurement of health status, (3)instrument for measurement of self-care. (4)record for follow-up management, and (5)instrument to measure patient satisfaction. Also, the five instruments can be used to evaluate the effectiveness of the service to assure quality. Further research is needed to increase the reliability and validity of instrument through a community-based HCN evaluation.

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A Research of Standards for Radiopharmaceutical Doses in Pediatric Nuclear Medicine (소아 핵의학 검사 시 사용되는 방사성의약품의 양 산출 기준 조사)

  • Do, Yong-Ho;Kim, Gye-Hwan;Lee, Hong-Jae;Kim, Jin-Eui;Kim, Hyun-Joo
    • The Korean Journal of Nuclear Medicine Technology
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    • v.13 no.1
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    • pp.47-50
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    • 2009
  • Purpose: Presently, any exact standard of radiopharmaceutical doses in pediatric nuclear medicine doesn't exist in the universe. So hospitals are following by manual of vial kit or guidelines of America and Europe based on recommended adult doses adjusted for body mass (MBq/kg) or body surface area (MBq/$m^2$). However, especially for children younger than 1 year and heavier than 50 kg, it's hard to estimate exact dosage for those children. Materials and Methods: In order to obtain objective data of multipliers for pediatric studies, we surveyed 4 major hospitals in Korea. After receiving feedbacks, we changed dosage to multiplier. And we compared multipliers of Korea to America's and Europe's. Results: Most hospitals in Korea are following by body mass formula (MBq/kg). On the other hand, standards don't include proper factors for a child younger than 1 year and heavier than 50 kg. Multipliers for 3 kg children who are injected lower doses than needed are America:0.12, Europe:0.09, Korea:0.05, multipliers for 30 kg children who are injected proper doses are America:0.58, Europe:0.51, Korea:0.45 and multipliers for 60 kg children who are injected more doses than needed are America:0.95, Europe:0.95, Korea:0.91. Conclusions : Through the survey, when calculating doses for children, usually output doses are based on adult doses adjusted for body mass (MBq/kg) but research has shown that standards of all of the compared standards don't reflect exact multipliers for children younger than 1 year and heavier than 50 kg. Therefore, we should give an effort to reduce needless radiation exposure in children by establishing a proper doses standard and also developing better image reconstruction software.

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Studies on the Indigenous Vesicular-Arbuscular Mycorrhizal Fungi(VAMF) in Horticultural Crops Grown Under Greenhouse -III. Effects of the Indigenous VAMF Inoculation on the Early Growth and the Subsquent Growth after Transplanting of Greenhouse Grown Crops (시설원예(施設園藝) 작물(作物)에서 토착(土着) VA균근균(菌根菌)에 관한 연구(硏究) -III. 토착(土着) VA 균근균(菌根菌) 접종효과)

  • Sohn, Bo-Kyoon;Yang, Won-Mo;Kim, Kwang-Sik
    • Korean Journal of Soil Science and Fertilizer
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    • v.25 no.1
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    • pp.99-107
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    • 1992
  • Effects of the indigenous Vesicular-arbuscular mycurrhizal fungi(VAMF) on early growth response of greenhouse grown crops were experimented. This study was done to evaluate the benefit of indigenous VAMF inoculation on the early growth and the subsequent growth after transplanting of some crops such as cucumber, tomato, hot pepper, eggplant, and melon. Leaf area, shoot dry weight, and plant length of mycorrhizal greenhouse crops showed the tendency of significant or no significant increase over control plants receiving no inoculation. The levels of VA mycorrhizal colonization were increased with plant growth, and infection rates of horticultural crop except hot pepper around one week after transplanting were decreased, while that of 8 weeks after emergence of mycorrhizal seedlings were increased again and infected by around 50% at harvesting time. In spore densities in the rhizosphere soil of craps experimented, the number of spore ranged from $72.7{\pm}26.3$ to $100{\pm}10.3g^1$ on dried soil basis and high density showed in both cucumber and tomato. Total nitrogen contents in shoots were lower in the mycorrhizal plants than non-mycorrhizal one, whereas P uptake in mycorrhizal hot pepper and tomato were highly ramarkable. The K contents in the shoots of mycorrhizal cucumber and eggplent were highly enhanced. Inoculation of the indigenous VAMF enhanced shoot Ca and Mg in both tomoto and melon. The contents of Fe, Zn, Mn and Cu in shoots of mycorrhizal crops were higher than non-mycorrhizal plants and vice versa in case of eggplent. Inoculation of the indigenous VAMF to horticultural crops were effective for alleviation of transplanting shock, and pretransplanting infection improved subsequent growth by reducing the time required for establishment of a functional mycorrhizal symbiosis following transplanting.

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Soft tissue changes associated with advancement genioplasty in skeletal class III individuals receiving mandibular set-back surgery (골격성 III급 부정교합자에서 전진이부성헝술을 동반한 하악 후퇴술 후 연조직 외형의 변화)

  • Kim, Keun-Ryoung;Kim, Seong-Sik;Son, Woo-Sung;Park, Soo-Byung
    • The korean journal of orthodontics
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    • v.38 no.2
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    • pp.104-120
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    • 2008
  • Purpose: The purpose of this study was to assess the hard and soft tissue changes associated with mandibular bilateral sagittal split osteotomy and genioplasty. Methods: This is a retrospective study of 40 patients who underwent either bilateral sagittal split osteotomy for mandibular setback (BSSO group, n = 20) or in combination with advancement genioplasty (Genio group, n = 20). Lateral radiographs, were taken before and immediately after surgery, and at least 6 months after surgery. Results: Comparing hard and soft tissue changes between the BSSO group and Genio group, there were significant differences in the lower incisor, soft tissue B point (B'), and soft tissue Pogonion (Pg') (p < 0.5). The mean ratio of hard and soft tissue changes for B/B', Pg/Pg', and Menton/soft tissue Menton after surgery in the BSSO group was 0.997, 0.965, and 1.022 respectively, and 0.824, 0.602, and 0.887 respectively in the genio group. Significant differences were found between the two groups. There were significant differences in lip thickness (B-B', Pg-Pg') in the Genioplasty group between pre and postsurgery, but not in the BSSO group. Pogonion to Labrale inferior and B' had a correlation coefficient of 0.833, 0.922, respectively for the BSSO group, and 0.775, 0.799 for the Genio group. Conclusions: The results indicate that there is a significant difference between bilateral sagittal split osteotomy with or without genioplasty in the lower facial esthetics values. The combination of mandibular setback and genioplasty had a smaller change in soft tissue thickness of the symphysis area after surgery than that of mandibular setback only.

A report on operating a nationwide human milk bank in Korea (전국규모 모유은행 운영보고)

  • Song, Kang-Hoon;Lee, Yoo-Min;Chang, Ji-Young;Park, Eun-Young;Park, Sung-Ae;Cho, Nam-Kyu;Bae, Chong-Woo
    • Clinical and Experimental Pediatrics
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    • v.53 no.4
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    • pp.488-494
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    • 2010
  • Purpose : A human milk bank collects, processes, eliminates, and stores breast milk from donors and provides breast milk to those in need. The authors hereby present the experiences and the objective lessons obtained through operating a nationwide human milk bank over a period of 2 years. Methods : The characteristics of the donors and the recipients and the amounts of breast milk donated, processed, and received at the East-West Neo Medical Center Human Milk Bank were investigated from August 2007 to August 2009. Results : The donor pool consisted of 131 first-time donors and 39 repeat donors who made 341 and 127 donations, respectively. Seventy-nine percent of the donors resided in the Seoul-Kyunggi area, and 60% of the donors were in their 30s. Most information and motivation came from the Internet (66%) or television (14%). A total of 2,736 L of breast milk was collected, and 1,979 L were processed. The cumulative number of recipients was 160 preterm or full-term infants and 21 adults, each group receiving the breast milk 337 and 41 times, respectively. In total, infants received 1,663 L and adults received 179 L. Conclusion : Through the present study, the role and importance of a human milk bank in collecting, pasteurizing, and storing surplus breast milk in through sanitary, medically proven methods and providing this breast milk to recipients could be appreciated and reevaluated. The authors believe that a national support system is necessary to expand this practice to a nationwide scale.

Beam Shaping by Independent Jaw Closure in Steveotactic Radiotherapy (정위방사선치료 시 독립턱 부분폐쇄를 이용하는 선량분포개선 방법)

  • Ahn Yong Chan;Cho Byung Chul;Choi Dong Rock;Kim Dae Yong;Huh Seung Jae;Oh Do Hoon;Bae Hoonsik;Yeo In Hwan;Ko Young Eun
    • Radiation Oncology Journal
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    • v.18 no.2
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    • pp.150-156
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    • 2000
  • Purpose : Stereotactic radiation therapy (SRT) can deliver highly focused radiation to a small and spherical target lesion with very high degree of mechanical accuracy. For non-spherical and large lesions, however, inclusion of the neighboring normal structures within the high dose radiation volume is inevitable in SRT This is to report the beam shaping using the partial closure of the independent jaw in SRT and the verification of dose calculation and the dose display using a home-made soft ware. Materials and Methods : Authors adopted the idea to partially close one or more independent collimator jaw(5) in addition to the circular collimator cones to shield the neighboring normal structures while keeping the target lesion within the radiation beam field at all angles along the arc trajectory. The output factors (OF's) and the tissue-maximum ratios (TMR's) were measured using the micro ion chamber in the water phantom dosimetry system, and were compared with the theoretical calculations. A film dosimetry procedure was peformed to obtain the depth dose profiles at 5 cm, and they were also compared with the theoretical calculations, where the radiation dose would depend on the actual area of irradiation. Authors incorporated this algorithm into the home-made SRT software for the isodose calculation and display, and was tried on an example case with single brain metastasis. The dose-volume histograms (DVH's) of the planning target volume (PTV) and the normal brain derived by the control plan were reciprocally compared with those derived by the plan using the same arc arrangement plus the independent collimator jaw closure. Results : When using 5.0 cm diameter collimator, the measurements of the OF's and the TMR's with one independent jaw set at 30 mm (unblocked), 15.5 mm, 8.6 mm, and 0 mm from th central beam axis showed good correlation to the theoretical calculation within 0.5% and 0.3% error range. The dose profiles at 5 cm depth obtained by the film dosimetry also showed very good correlation to the theoretical calculations. The isodose profiles obtained on the home-made software demonstrated a slightly more conformal dose distribution around the target lesion by using the independent jaw closure, where the DVH's of the PTV were almost equivalent on the two plans, while the DVH's for the normal brain showed that less volume of the normal brain receiving high radiation dose by using this modification than the control plan employing the circular collimator cone only. Conclusions : With the beam shaping modification using the independent jaw closure, authors have realized wider clinical application of SRT with more conformal dose planning. Authors believe that SRT, with beam shaping ideas and efforts, should no longer be limited to the small spherical lesions, but be more widely applied to rather irregularly shaped tumors in the intracranial and the head and neck regions.

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