• 제목/요약/키워드: 대상선정방법

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Weight loss effects of Bariatric Surgery after nutrition education in extremely obese patients (고도비만환자에서 베리아트릭 수술 (Bariatric Surgery) 후 영양교육이 체중감량에 미치는 효과)

  • Jeong, Eun-Ha;Lee, Hong-Chan;Yim, Jung-Eun
    • Journal of Nutrition and Health
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    • v.48 no.1
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    • pp.30-45
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    • 2015
  • Purpose: This study was planned to determine the characteristics of extremely obese patients during Bariatric surgery and to evaluate how the difference in the number of postsurgical personal nutritional educations they received affected the weight loss. Methods: This is a retrospective study on the basis of the medical records of extremely obese patients for 15 months after receiving gastric banding. A total of 60 people were selected as the study subjects and they were divided into the Less Educated Group and the More Educated Group according to the average number of personal nutritional educations they received. We investigated both groups to determine the general characteristic, health related lifestyle habits, obesity related complications and symptoms in possession, and eating habits before their surgery, the body composition measurement result, obesity determination indices at 1, 3, 6, 9, 12, and 15 months before and after their surgery, and the biochemical parameters at 6 months before and after their surgery. Results: Body fat and weight showed rapid reduction until 6 months after the surgery, but thereafter reduced slowly depending on the result of body composition measurement. Regarding body fat and weight, the More Educated Group, who received nutrition education more often, showed significantly lower levels than the Less Educated Group at 15 months after surgery. Regarding BMI and degree of obesity, the More Educated Group showed significantly lower levels than the Less Educated Group at 15 months after surgery. Here, we were assured that BMI is reversely proportional to the number of personal nutritional educations at 15 months, which is more outstanding after surgery than before surgery. Conclusion: Long-term nutritional education is a key factor for the extremely obese patient in maintaining the effects of Bariatric surgery on weight and body fat reduction onwards. In the next stage, considering the characteristics of the study subjects, adoption of individual nutrition education is recommended for postsurgical prospective arbitration of obesity in order to monitor blood pressure, obesity related complications, symptoms in possession, and how eating habits and health related life habits change, and to judge the actual effect of the nutritional education method at the same time.

Diagnosis of Obstructive Sleep Apnea Syndrome Using Overnight Oximetry Measurement (혈중산소포화도검사를 이용한 폐쇄성 수면무호흡증의 흡증의 진단)

  • Youn, Tak;Park, Doo-Heum;Choi, Kwang-Ho;Kim, Yong-Sik;Woo, Jong-Inn;Kwon, Jun-Soo;Ha, Kyoo-Seob;Jeong, Do-Un
    • Sleep Medicine and Psychophysiology
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    • v.9 no.1
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    • pp.34-40
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    • 2002
  • Objectives: The gold standard for diagnosing obstructive sleep apnea syndrome (OSAS) is nocturnal polysomnography (NPSG). This is rather expensive and somewhat inconvenient, however, and consequently simpler and cheaper alternatives to NPSG have been proposed. Oximetry is appealing because of its widespread availability and ease of application. In this study, we have evaluated whether oximetry alone can be used to diagnose or screen OSAS. The diagnostic performance of an analysis algorithm using arterial oxygen saturation ($SaO_2$) base on 'dip index', mean of $SaO_2$, and CT90 (the percentage of time spent at $SaO_2$<90%) was compared with that of NPSG. Methods: Fifty-six patients referred for NPSG to the Division of Sleep Studies at Seoul National University Hospital, were randomly selected. For each patient, NPSG with oximetry was carried out. We obtained three variables from the oximetry data such as the dip index most linearly correlated with respiratory disturbance index (RDI) from NPSG, mean $SaO_2$, and CT90 with diagnosis from NPSG. In each case, sensitivity, specificity and positive and negative predictive values of oximetry data were calculated. Results: Thirty-nine patients out of fifty-six patients were diagnosed as OSAS with NPSG. Mean RDI was 17.5, mean $SaO_2$ was 94.9%, and mean CT90 was 5.1%. The dip index [4%-4sec] was most linearly correlated with RDI (r=0.861). With dip index [4%-4sec]${\geq}2$ as diagnostic criteria, we obtained sensitivity of 0.95, specificity of 0.71, positive predictive value of 0.88, and negative predictive value of 0.86. Using mean $SaO_2{\leq}97%$, we obtained sensitivity of 0.95, specificity of 0.41, positive predictive value of 0.79, and negative predictive value of 0.78. Using $CT90{\geq}5%$, we obtained sensitivity of 0.28, specificity of 1.00, positive predictive value of 1.00, and negative predictive value of 0.38. Conclusions: The dip index [4%-4sec] and mean $SaO_2{\leq}97%$ obtained from nocturnal oximetry data are helpful in diagnosis of OSAS. CT90${\leq}$5% can be also used in excluding OSAS.

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COMPARISON OF POLYMERIZATION SHRINKAGE AND STRAIN STRESS OF SEVERAL COMPOSITE RESINS USING STRAIN GUAGE (스트레인 게이지를 이용한 수종의 복합레진의 중합수축 및 수축응력의 비교)

  • Kim, Young-Kwang;Yoo, Seung-Hoon;Kim, Jong-Soo
    • Journal of the korean academy of Pediatric Dentistry
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    • v.31 no.3
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    • pp.516-526
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    • 2004
  • Polymerization shrinkage of photoinitiation type composite resin cause several clinical problems. The purpose of this study was to evaluate the shrinkage strain stress, linear polymerization shrinkage, compressive strength and microhardness of recently developed composite resins. The composite resins were divided into four groups according to the contents of matrix and filler type. Group I : $Denfil^{TM}$(Vericom, Korea) with conventional matrix, Group II : $Charmfil^{(R)}$(Dentkist, Korea) with microfiller and nanofller mixture, Group III : $Filtek^{TM}$ Z250(3M-ESPE, USA) TEGDMA replaced by UDMA and Bis-EMA(6) in the matrix, and Group IV : $Filtek^{TM}$ Supreme(3M-ESPE, USA) using pure nanofiller. Preparation of acrylic molds were followed by filling and curing with light gun. Strain gauges were attached to each sample and the leads were connected to a strainmeter. With strainmeter shrinkage strain stress and linear polymerization shrinkage was measured for 10 minutes. The data detected at 1 minute and 10 minutes were analysed statistically with ONE-way ANOVA test. To evaluate the mechanical properties of tested materials, compressive hardness test and microhardness test were also rendered. The results can be summarized as follows : 1. Filling materials in acrylic molds showed initial temporary expansion in the early phase of polymerization. This was followed by contraction with the rapid increase in strain stress during the first 1 minute and gradually decreased during post-gel shrinkage phase. After 1 minute, there's no statistical differences of strain stress between groups. The highest strain stress was found in group IV and followed by group III, I, II at 10 minutes-measurement(p>.05). In regression analysis of strain stress, group III showed minimal inclination and followed by group II, I, IV during 1 minute. 2. In linear polymerization shrinkage test, the composite resins in every group showed initial increase of shrinkage velocity during the first 1 minute, followed by gradually decrease of shrinkage velocity. After 1 minute, group IV and group III showed statistical difference(p<.05). After 10 minutes, there were statistical differences between group IV and group I, III(p<.05) and between group II and group III(p<.05). In regression analysis of linear polymerization shrinkage, group II showed minimal inclination and followed by group IV, III, I during 1 minute. 3. In compressive strength test, group III showed the highest strength and followed by group II, IV, I. There were statistical differences between group III and group IV, I(p<.05). 4. In microhardness test, upper surfaces showed higher value than lower surfaces in every group(p<.05).

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Analysis and Improvement Strategies for Korea's Cyber Security Systems Regulations and Policies

  • Park, Dong-Kyun;Cho, Sung-Je;Soung, Jea-Hyen
    • Korean Security Journal
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    • no.18
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    • pp.169-190
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    • 2009
  • Today, the rapid advance of scientific technologies has brought about fundamental changes to the types and levels of terrorism while the war against the world more than one thousand small and big terrorists and crime organizations has already begun. A method highly likely to be employed by terrorist groups that are using 21st Century state of the art technology is cyber terrorism. In many instances, things that you could only imagine in reality could be made possible in the cyber space. An easy example would be to randomly alter a letter in the blood type of a terrorism subject in the health care data system, which could inflict harm to subjects and impact the overturning of the opponent's system or regime. The CIH Virus Crisis which occurred on April 26, 1999 had significant implications in various aspects. A virus program made of just a few lines by Taiwanese college students without any specific objective ended up spreading widely throughout the Internet, causing damage to 30,000 PCs in Korea and over 2 billion won in monetary damages in repairs and data recovery. Despite of such risks of cyber terrorism, a great number of Korean sites are employing loose security measures. In fact, there are many cases where a company with millions of subscribers has very slackened security systems. A nationwide preparation for cyber terrorism is called for. In this context, this research will analyze the current status of Korea's cyber security systems and its laws from a policy perspective, and move on to propose improvement strategies. This research suggests the following solutions. First, the National Cyber Security Management Act should be passed to have its effectiveness as the national cyber security management regulation. With the Act's establishment, a more efficient and proactive response to cyber security management will be made possible within a nationwide cyber security framework, and define its relationship with other related laws. The newly passed National Cyber Security Management Act will eliminate inefficiencies that are caused by functional redundancies dispersed across individual sectors in current legislation. Second, to ensure efficient nationwide cyber security management, national cyber security standards and models should be proposed; while at the same time a national cyber security management organizational structure should be established to implement national cyber security policies at each government-agencies and social-components. The National Cyber Security Center must serve as the comprehensive collection, analysis and processing point for national cyber crisis related information, oversee each government agency, and build collaborative relations with the private sector. Also, national and comprehensive response system in which both the private and public sectors participate should be set up, for advance detection and prevention of cyber crisis risks and for a consolidated and timely response using national resources in times of crisis.

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A Consideration of Apron's Shielding in Nuclear Medicine Working Environment (PET검사 작업환경에 있어서 APRON의 방어에 대한 고찰)

  • Lee, Seong-wook;Kim, Seung-hyun;Ji, Bong-geun;Lee, Dong-wook;Kim, Jeong-soo;Kim, Gyeong-mok;Jang, Young-do;Bang, Chan-seok;Baek, Jong-hoon;Lee, In-soo
    • The Korean Journal of Nuclear Medicine Technology
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    • v.18 no.1
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    • pp.110-114
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    • 2014
  • Purpose: The advancement in PET/CT test devices has decreased the test time and popularized the test, and PET/CT tests have continuously increased. However, this increases the exposure dose of radiation workers, too. This study aims to measure the radiation shielding rate of $^{18}F-FDG$ with a strong energy and the shielding effect when worker wore an apron during the PET/CT test. Also, this study compared the shielding rate with $^{99m}TC$ to minimize the exposure dose of radiation workers. Materials and Methods: This study targeted 10 patients who visited in this hospital for the PET/CT test for 8 days from May 2nd to 10th 2013, and the $^{18}F-FDG$ distribution room, patient relaxing room (stand by room after $^{18}F-FDG$ injection) and PET/CT test room were chosen as measuring spots. Then, the changes in the dose rate were measured before and after the application of the APRON. For an accurate measurement, the distance from patients or sources was fixed at 1M. Also, the same method applied to $^{99m}TC's$ Source in order to compare the reduction in the dose by the Apron. Results: 1) When there was only L-block in the $^{18}F-FDG$ distribution room, the average dose rate was $0.32{\mu}Sv$, and in the case of L-blockK+ apron, it was $0.23{\mu}Sv$. The differences in the dose and dose rate between the two cases were respectively, $0.09{\mu}Sv$ and 26%. 2) When there was no apron in the relaxing room, the average dose rate was $33.1{\mu}Sv$, and when there was an apron, it was $22.3{\mu}Sv$. The differences in the dose and dose rate between them were respectively, $10.8{\mu}Sv$ and 33%. 3) When there was no APRON in the PET/CT room, the average dose rate was $6.9{\mu}Sv$, and there was an APRON, it was $5.5{\mu}Sv$. The differences in the dose and dose rate between them were respectively, $1.4{\mu}Sv$ and 25%. 4) When there was no apron, the average dose rate of $^{99m}TC$ was $23.7{\mu}Sv$, and when there was an apron, it was $5.5{\mu}Sv$. The differences in the dose and dose rate between them were respectively, $18.2{\mu}Sv$ and 77%. Conclusion: According to the result of the experiment, $^{99m}TC$ injected into patients showed an average shielding rate of 77%, and $^{18F}FDG$ showed a relatively low shielding rate of 27%. When comparing the sources only, $^{18F}FDG$ showed a shielding rate of 17%, and $^{99m}TC$'s was 77%. Though it had a lower shielding effect than $^{99m}TC$, $^{18}F-FDG$ also had a shielding effect on the apron. Therefore, it is considered that wearing an apron appropriate for high energy like $^{18}F-FDG$ would minimize the exposure dose of radiation workers.

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Correlation between High-Resolution CT and Pulmonary Function Tests in Patients with Emphysema (폐기종환자에서 고해상도 CT와 폐기능검사와의 상관관계)

  • Ahn, Joong-Hyun;Park, Jeong-Mee;Ko, Seung-Hyeon;Yoon, Jong-Goo;Kwon, Soon-Seug;Kim, Young-Kyoon;Kim, Kwan-Hyoung;Moon, Hwa-Sik;Park, Sung-Hak;Song, Jeong-Sup
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.3
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    • pp.367-376
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    • 1996
  • Background : The diagnosis of emphysema during life is based on a combination of clinical, functional, and radiographic findings, but this combination is relatively insensitive and nonspecific. The development of rapid, high-resolution third and fourth generation CT scanners has enabled us to resolve pulmonary parenchymal abnormalities with great precision. We compared the chest HRCT findings to the pulmonary function test and arterial blood gas analysis in pulmonary emphysema patients to test the ability of HRCT to quantify the degree of pulmonary emphysema. Methods : From october 1994 to october 1995, the study group consisted of 20 subjects in whom HRCT of the thorax and pulmonary function studies had been obtained at St. Mary's hospital. The analysis was from scans at preselected anatomic levels and incorporated both lungs. On each HRCT slice the lung parenchyma was assessed for two aspects of emphysema: severity and extent. The five levels were graded and scored separately for the left and right lung giving a total of 10 lung fields. A combination of severity and extent gave the degree of emphysema. We compared the HRCT quantitation of emphysema, pulmonary function tests, ABGA, CBC, and patients characteristics(age, sex, height, weight, smoking amounts etc.) in 20 patients. Results : 1) There was a significant inverse correlation between HRCT scores for emphysema and percentage predicted values of DLco(r = -0.68, p < 0.05), DLco/VA(r = -0.49, p < 0.05), FEV1(r = -0.53, p < 0.05), and FVC(r = -0.47, p < 0.05). 2) There was a significant correlation between the HRCT scores and percentage predicted values of TLC(r = 0.50, p < 0.05), RV(r = 0.64, p < 0.05). 3) There was a significant inverse correlation between the HRCT scores and PaO2(r = -0.48, p < 0.05) and significant correlation with D(A-a)O2(r = -0.48, p < 0.05) but no significant correlation between the HRCT scores and PaCO2. 4) There was no significant correlation between the HRCT scores and age, sex, height, weight, smoking amounts in patients, hemoglobin, hematocrit, and wbc counts. Conclusion : High-Resolution CT provides a useful method for early detection and quantitating emphysema in life and correlates significantly with pulmonary function tests and arterial blood gas analysis.

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Development and evaluation of Home Economics teaching·learning process plans applied Problem Based Learning focusing on 'food and nutrition' unit for students with intellectual disability (지적장애 학생을 위한 문제중심학습(PBL) 적용 가정과 식생활 교수·학습 과정안 개발과 평가)

  • Kim, yun-ju;Chae, Jung-Hyun
    • Journal of Korean Home Economics Education Association
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    • v.30 no.2
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    • pp.39-56
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    • 2018
  • The purpose of this study was to develop Home Economics(HE) teaching and learning process plans applied Problem Based Learning(PBL) focusing on 'food and nutrition' unit for students with intellectual disability and to evaluate the effects of the HE instruction on their food choice·management knowledge and problem-solving skills after implementing the instruction for students with intellectual disability. To develop HE teaching and learning process plans applied PBL focusing on 'food and nutrition' unit for students with intellectual disability, problems that arise in daily life to trigger interest of students were firstly developed. The selected problems and teaching and learning process plans were reviewed for validity by one home economics education professor and three teachers who are experts in special education. This study used the one group pretest and posttest design, sampling 6 students who are in special-education middle school with the intellectual disability. After HE instruction of 6 sessions applied PBL method, this study tested the effects of the instruction. The first three sessions taught how to choose and keep food. The fourth session taught purchasing food ingredients and keeping them for sandwiches. The fifth and sixth sessions let the students make sandwiches and give them to others. The instruments of the study comprised of tools for food choice and management knowledge, tools for problem-solving skills evaluation, self-evaluation sheets, evaluation form of course satisfaction for students, evaluation form of behavior in class for teachers, and daily observation journal and all tools. These instruments were proved to have reliability and validity. The results of this study are as follows. First, all six students who took HE instruction applied PBL method focusing on 'food and nutrition' unit scored 30 points higher out of 100 points after taking the instruction in food choice and management knowledge and scored 5 points higher out of 14 points in problem-solving skills on average. Therefore, it was interpreted that HE instruction applied PBL affected the food choice·management knowledge and the problem solving skills of students with intellectual disability. Secondly, the students with intellectual disability participated actively in HE instruction applied PBL focusing on 'food and nutrition' unit and expressed satisfaction. Three special education experts evaluated HE teaching·learning process plans applied PBL focusing on 'food and nutrition' unit to be well-developed. This study showed that HE instruction applied PBL focusing on 'food and nutrition' unit allowed the students with intellectual disability to acquire comprehensive skills in choosing, keeping, and making safe food and helped them solve problems of their life by themselves. Therefore I suggest that Home Economics should be adopted as a formal subject matter in special school curriculum for students with intellectual disability.

The relationships between lead exposure indicies and urinary δ-ALA by HPLC and colorimetric method in lead exposure workers (연노출근로자에 있어서 흡광광도법과 HPLC법에 의한 요중 δ-ALA 배설량과 연노출지표들 간의 관련성)

  • Ahn, Kyu-Dong;Lee, Sung-Soo;Hwangbo, Young;Lee, Gab-Soo;Yeon, You-Yong;Kim, Yong-Bae;Lee, Byung-Kook
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.6 no.1
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    • pp.77-87
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    • 1996
  • In order to compare the difference of the measurement of delta aminolevulinic acid(${\delta}$-ALA) in urine between HPLC method(HALA) and colorimetric method(CALA), and also to provide useful information for the new diagnostic criteria of ${\delta}$-ALA in urine in lead poisoning, if at all possible in the future, authors studied 234 male lead workers who were selected from 7 storage battery factories, 3 secondary smelting industries, and 2 litharge making industries. Study subjects were selected on the basis of blood Zinc protoporphyrin(ZPP) level from low to high concentration to cover wide range of lead exposure. Study variables for this study were ${\delta}$-ALA measured by two different methods, blood lead(PbB), and blood ZPP. The results were as follows: 1. There was very high correlation between ${\delta}$-ALA measured by two method(r = 0.989 : HALA = -0.8194 + 0.8110 ${\times}$ CALA), but the value of CALA was measured about 2mg/L greater than HALA. 2. While the correlations of ${\delta}$-ALA by two method with blood lead and blood ZPP were 0.46 and 0.37 respectively, they were increased to 0.63 and 0.57 if ${\delta}$-ALA values were log-transformed. 3. Simple linear regression of ${\delta}$-ALA measured by two method on ZPP were as follows: CALA = 2.0421 + 0.0341 ${\times}$ ZPP ($R^2=0.1385$ p = 0.0001) HALA = 0.8006 + 0.0280 ${\times}$ ZPP ($R^2=0.1389$ p = 0.0001) 4. Simple linear regression of ${\delta}$-ALA measured by two method on PbB were as follows: CALA = - 0.4134 + 0.1545 ${\times}$ PbB ($R^2=0.2085$ p = 0.0001) HALA = -1.2893 + 0.1287 PbB ($R^2=0.2154$ p = 0.0001), 5. Simple linear regression of log-transformed ${\delta}$-ALA by two method on ZPP and PbB were as follows: logHALA = 0.3078 + 0.0060 ZPP ($R^2=0.3329$ p = 0.0001) logCALA = 1.0189 + 0.0044 ZPP ($R^2=0.3290$ p = 0.0001) logHALA = -0.0221 + 0.0246 PbB ($R^2=0.4046$ p = 0.0001) logCALA = 0.7662 + 0.0184 PbB ($R^2=0.4108$ p = 0.0001) 6. The cumulative percent of colorimetric method to detect lead workers whose value of PbS and ZPP were over screening level such as $40{\mu}/dl$ and $100{\mu}/dl$ respectively was higher than HPLC method if cut-off level of ${\delta}$-ALA for screening of lead poisoning was 5 mg/L. But if cut-off level of ${\delta}$-ALA measured by HPLC was reduced to 3 mg/L which is compatible to 5 mg/L of ${\delta}$-ALA measured by colorimetric method, there were good agreement between two methods and showed dose-response relationship with other lead exposure indices such as PbB and ZPP.

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An influence of operator's posture on the shape of prepared tooth surfaces for fixed partial denture (진료자세가 고정성 국소의치의 지대치 삭제에 미치는 영향)

  • Won, In-Jae;Kwon, Kung-Rock;Pae, Ah-Ran;Choi, Dae-Gyun
    • The Journal of Korean Academy of Prosthodontics
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    • v.49 no.1
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    • pp.38-48
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    • 2011
  • Purpose: Dentists suffer back, neck and shoulder pain during their careers due to bad operating posture. If dentists have a good operating posture ergonomically, there would be less pain and discomfort in the shoulder and back. Therefore, dentists should learn the Home position which enables dentists to approach a stable posture ergonomically. This study was to compare tooth preparation in the Home position and the Random position, and evaluate the clinical efficacy of the Home position. Materials and methods: Tooth preparation for fixed partial denture was performed on the maxillary left 2nd premolar and maxillary left 2nd molar at the two different operating positions were compared. The amount of occlusal reduction, marginal width, subgingival margin depth, and convergence angle were measured. A T-test was performed separately to compare the results of the Random position and the Home position. Results: 1. The amounts of average thickness of occlusal reduction on fossa were deficient to the ordered ones in the Random position and the Home position (P > .05). 2. The average subgingival margin depth of prepared margin on maxillary left 2nd premolar, maxillary left 2nd molar were excessive in the Random position than in the Home position. On the maxillary left 2nd premolar, there was no statistical difference in the Random position and the Home position except Distal midline, DL line angle, Lingual midline, ML line angle (P< .05). On the maxillary left 2nd molar, there was no statistical difference in the Random position and the Home position (P < .05). 3. Average convergence angle in the Random position and the Home position were excessive compared to the ordered angle. There was no statistical difference in the Random position and the Home position (P > .05). 4. Analysis of pearson correlation : In the Random position, the amounts of average thickness of occlusal reduction, the average subgingival margin depth of prepared margin, convergence angle were significantly associated with each other (P < .05). But in the Home position, they were not significantly associated with each other (P < .05). 5. The time needed for preparation in the Home position was faster or equal than that of the Random position as time went on. Conclusion: In conclusion, there were no significant differences between Home position and Random position in measures of occlusal reduction, marginal width, marginal depth, convergence angle. However, preparation time and incidence of damaging adjacent teeth were less in Home position than in Random position. Therefore, if trained properly, Home position which is more ergonomically stable can be adopted for clinical use.

Leukocyte count and hypertension in the health screening data of some rural and urban residents (일부 농촌과 도시의 건강선별조사 자료로 본 백혈구수와 고혈압과의 관계)

  • Lee, Choong-Won;Yoon, Nung-Ki;Lee, Sung-Kwan
    • Journal of Preventive Medicine and Public Health
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    • v.24 no.3 s.35
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    • pp.363-372
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    • 1991
  • We used the health screening data of some rural and urban residents to examine the cross-sectional association between leukocyte count and hypertension. The 206 male and 203 female rural residents were selected by multi-stage cluster sampling method in Kyungsan-Kun area of Kyungbuk province in 1985 and 600 urban residents were selected by the same sampling method as the rural residents in Daegu city of the same province in 1986 compatible with age-sex distribution of Daegu city of 1985 census, but of whom 384 actually responded. The rest of 600 were replaced by age and sex with those who were members of the medical insurance plan visiting the health management department of the university hospital to get the biannual preventive medical checkups. Excluded in the analysis were those having hypertensive history, diseases and extreme outlying values of the screening tests, leaving 373 rural and 571 urban residents. Leukocyte count was measured with ELT-8 Laser shadow method and the unit $cells/mm^3$, Blood pressures were determined with an aneroid sphygmomanometer with pre-standardized method and hypertensives were defined as those showing systolic blood pressure more than 140mmHg and/or diastolic blood pressure more than 90mmHg. Total residents pooled (N=944) showed a significant difference between hypertensives and normotensives ($6965.93{\pm}1997.01\;vs\;6490.61{\pm}1941.32,\;P=0.00$) and in rural residents was noted the similar significant difference (P=0.03). None of significant differences were noted in any stratum stratified by residency and sex. Compared to the lowest quintile of WBC, 2/5 quintile showed odds ratio 0.99 (95% Confidence interval, Ci 0.62-1.59), 3/5 quintile 1.41 (95% CI 0.90-2.21), 4/5 quintile 1.76 (95% CI. 1.14-2.72), and highest quintile 1.80 (1.15-2.82) in the total residents. Likelihood ratio test for linear trend for it indicated a significant trend ($X^2_{trend}=5.53,\;df=1,\;P<0.05$). There were no other significant odds ratios compared to the lowest quintile of WBC in strata stratified by residency and sex. The odds ratios in total residents which had showed significant odds ratios became nonsignificant and of reduced magnitude after controlling age, frequency of smoking and drinking with multiple logistic. regression. In each stratum, it changed magnitudes of odds ratios slightly and unstably. None of the trend tests showed any significant trend. These results suggest that the Friedman et al's finding of association between leukocyte count and hypertension may be due to an statistical type I error resulting from the data dredging in an exploratory study, in which more than 800 variables were screened as possible predictors of hypertension.

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