• Korean Chemical Engineering Research
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• 제49권2호
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• pp.238-243
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• 2011

본 연구는 기존의 인공심폐기의 단점을 보완하기 위하여 혈액펌프를 사용하지 않고 혈류의 흐름을 유도할 수 있는 기구(balloon)형 인공심폐기 설계를 위한 구조적 해석을 시도하였다. 가상의 모형 인공심폐기 내에서의 혈류의 흐름패턴을 분석하기 위하여 CFD 모델링 방법을 사용하였다. 이 시스템의 작동원리는 막 산화기 주위를 기구를 사용하여 압력하중을 인가하여 주기적으로 수축.이완되도록 하였으며, 시간에 따라 변화하는 시간 함수 값은 sine 반주기와 sine 주기를 계산하여 적용하였다. 이와 같은 방법으로 기구형 인공심폐기를 설계할 경우 한 방향에 대한 혈류의 움직임을 유도할 수 있다는 가정 하에 구조적 해석을 하였다. 실험결과 CFD 시뮬레이션을 통하여 인공심폐기의 입구와 출구에 서의 혈류의 속도와 압력을 측정하여 분석한 결과 한 방향에 대한 혈류의 유동이 발생하는 것을 확인하였다. 이와 같은 CFD 시뮬레이션은 혈류의 흐름특성을 미리 예측할 수 있어 인공심폐기 설계에 있어서 최적화된 디자인을 제공할 수 있을 것이라 판단된다.

• Archives of Plastic Surgery
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• 제40권5호
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• pp.530-535
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• 2013

Background Platelet-rich plasma (PRP) has more concentrated platelets than normal plasma (approximately 150-400${\times}10^3$ cell/dL). Platelets excrete several growth factors and cytokines that are associated with the healing and regeneration process. However, even though PRP is widely used, the mechanism or actual effect is presently unclear. Therefore, this study was performed to investigate the levels of growth factors and platelet concentration rate. Methods Autologous blood for preparing PRP was obtained from healthy subjects aged 25 to 35 years. The samples were divided into 4 experimental groups (inactivated whole blood, inactivated PRP, activated whole blood with thrombin and calcium chloride, and activated PRP). The platelet counts in the blood were analyzed and the growth factors were quantitatively measured. A statistical analysis was performed by using Dunn's multiple comparison test. Results In the blood cell analysis, the platelet count of the PRP group was approximately 4.25 times higher than that of the whole blood group. In the quantitative analysis of growth factors, the platelet-derived growth factor (PDGF)-AB, PDGF-BB, and transforming growth factor-${\beta}$ of the inactivated and activated PRP groups were higher than those of the inactivated and activated whole blood groups (P<0.05). Conclusions In this study, the platelet count and the levels of PDGF-AB and PDGF-BB in the PRP were determined. Further, more research is required on the bioactivity level of the growth factors secreted during the process of PRP preparation and the potency of growth factors that can be exerted physiologically in vivo.

• Journal of Preventive Medicine and Public Health
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• 제32권3호
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• pp.415-420
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• 1999

Objectives: We investigated the effects of changes in obesity and life style factors, such as cigarette smoking, alcohol drinking, and exercise, on the changes in blood pressure and serum cholesterol among Korean men. Methods: This study included 7,205 healthy male employees in the steel manufacturing industry. Each subject underwent health examination in 1994 and was re-examined in 1997. The study subjects were classified into four categories, according to changes in body mass index (BMI) (loss; stable; mild gain: severe gain), cigarette smoking (quitter; nor-smoker; smoker continued; smoker started), alcohol drinking (quitter; non-drinker; drinker continued; drinker started) and exercise (more exercise; continuous regular exercise; continuous irregular or no exercise; less exercise), respectively. We evaluated the relationship between the categories of change in those independent variables and the changes in blood pressure and serum cholesterol, adjusted for BMI in 1994 and age by analysis of variance. Results: The change in systolic blood pressure was positively associated with the changes in BMI (p<0.001) and drinking (p=0,001), but negatively with smoking (p=0,004), compared to the first category of each independent variables. The systolic blood pressure was significantly less increased in the continuous smoking group than quitter or hon-smoker. The changes in diastolic blood pressure and serum cholesterol appeared to have statistically significant linear relationships only with the change in BMI. The change in exercise showed a marginal significance with diastolic blood pressure (p=0.088). Conclusions: These prospective data emphasize the importance of obesity as a determinant of the changes in blood pressure and serum cholesterol. In addition, the changes in smoking and drinking habits can affect systolic blood pressure.

• Journal of Nutrition and Health
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• 제36권1호
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• pp.75-82
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• 2003

It has been considered that high Na intake, and low Ca/K intake are related to the incidence of hypertension. In this preliminary study, dietary Na, K, and Ca intake and their urinary excretion in rural area in Kyungpook province were measured to recognize the relationship between those blood pressure-related minerals and blood pressure regulation in elderly people in rural area of South Korea. Sixty eight subjects (male 39, female 29) aged over 60 were randomly selected in rural area in South Korea. Blood pressure and soup saltness were measured, and dietary intake using 24 hours recall and urinary excretion of Na, K and Ca were measured. Depending on the blood pressure level, the data were analyzed using non-parametric ANOVA of Kruskal Wallis analysis on the basis of categorizing of one of four blood pressure groups, such as normal, high normal, hypertension I and hypertension II. Mean systolic (124.2$\pm$15.1 mmHg) and diastolic (79.0$\pm$10.2 mmHg) blood pressures were within the normal range. Soup saltiness and systolic pressure was positively correlated (p < 0.05). Even without statistical significance, dietary Na intake was higher in the upper systolic blood pressure groups then in the lower ones, which suggested higher Na intake caused the increase of blood pressure. No consistency was shown between the urinary concentration of Na, K, Ca level and blood pressure level, respectively. From the results of this study, it is assumed that high Na intake might be related to the incidence of hypertension. Further study with large sample size is needed to supplement the limitation of this preliminary study. (Korean J Nutrition 36 (1) : 75-82, 2003)

• 동의생리병리학회지
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• 제28권3호
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• pp.346-354
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• 2014

The study was performed to determine the reliability and validity of the 'Qi Blood Yin Yang Deficiency Questionnaire (Qi Blood Yin Yang DQ)' for the 100 subjects with chronic fatigue. After 100 subjects respond to the 'Qi Blood Yin Yang DQ', Korean medical doctor classified the subjects into 4 groups such as Qi deficiency group, Blood deficiency group, Yin deficiency group and Yang deficiency group. 100 subjects were retested in the same way after 3 weeks. The reliability and the validity of the questionnaire were inspected. Internal consistency of the 'Qi Blood Yin Yang DQ' was excellent (Cronbach alpha 0.916). Test-retest reliability was good (intra-class correlation coefficient 0.699). Construct validity analyzed by exploratory factor analysis produced 4 factors, which were selected from eigenvalues that are greater than 1.0. The 'Qi Blood Yin Yang DQ' consisted of 4 factors. The factor 1, 2, 3 and 4 showed 'Qi deficiency', 'Yin deficiency', 'Yang deficiency' and 'Blood deficiency' respectively. The 'Qi Blood Yin Yang DQ' restructured in this study may provide a fundamental questionnaire and a further study is required for a more advanced, standardized and statistically proven questionnaire.

• 대한의생명과학회지
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• 제18권4호
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• pp.377-383
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• 2012

Recent genome-wide association studies (GWAS) have identified a number of common variants associated with blood pressure homeostasis and hypertension in population. In the previous study, single nucleotide polymorphisms (SNPs) in the SLC4A4 gene have been reported to be associated with hypertension in Han Chinese population. We aimed to confirm whether the genetic variation of SLC4A4 gene influence the susceptibility to blood pressure and hypertension in Korean population. We genotyped variants in or near SLC4A4 in a population-based cohort including 7,551 unrelated Korean from Ansan and Ansung. Here, we performed association analysis to elucidate the possible relations of genetic polymorphisms in SLC4A4 gene with blood pressure traits. By examining genotype data of a total of 7,551 subjects in the Korean Association REsource (KARE) study, we discovered the SLC4A4 gene polymorphisms are associated with blood pressure and hypertension. The common and highest significant polymorphism was rs6846301 (${\beta}$=0.839, additive P=0.032) with systolic blood pressure (SBP), rs6846301 (${\beta}$=0.588, additive P=0.027) with diastolic blood pressure (DBP), and rs6846301 (OR=1.23, CI: 1.09~1.40, additive $P=1.2{\times}10^{-3}$) with hypertension. Furthermore, the SNP rs6846301 was consistently associated with both blood pressure and hypertension. Consequently, we found statistically significant SNPs in SLC4A4 gene that are associated with both blood pressure and hypertension traits. In addition, these results suggest that the individuals with the minor alleles of the SNP in the SLC4A4 gene may be more susceptible to the development of hypertension in the Korean population.

• 한국지역사회생활과학회지
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• 제14권1호
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• pp.107-117
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• 2003

This study was carried out to investigate the nutrients intakes, blood pressure, and correlations between these two factors in Korean rural adults(60 men, 60 women). Nutrients intakes were measured by analyzing with CAN Pro after weighing the each diets of the subjects had for 24 hours. We measured body mass index(BMI), waist to hip ratio(WHR), and fat content in the body besides blood pressure, and considered their relationship with blood pressure. This examination includes collections and analysis of serum and urine, and considers the correlations between blood pressure and serum or urinary factors. These results were as follows ; 1) The mean ages of men and women were 50.$\pm$12.6 and 46.0$\pm$12.5, respectively. The percentage of hypertensive was higher in men(43%) than in women(37%). 2) The values of WHR, body water and lean body mass were higher in men and the value of body fat was higher in women. Weight, BMI, waist or hip circumferences, and WHR were correlated with blood pressure in these subjects. 3) Though the levels of serum triglyceride, sodium, potassium and iron levels were higher in men and urinary Na was higher in women, these factors didn't showed any significant correlations with blood pressure in both sexes. 4) The values of calcium and vitamin B$_2$ intake in men and women, and of iron intake in women didn't meet the Korean recommended allowances(RDA). Animal protein and Na intakes were negatively correlated with blood pressure. These results showed that the levels of calcium and vitamin B$_2$ intake in both sexes and iron intake in women were lower than those of RDA, and weight, BMI, waist or hip circumferences and WHR were significantly correlated with blood pressure. Therefore we suggest that the farmers of this research need to increase intake of nutrients like calcium and vitamin B$_2$ and control the weight.

• Journal of Preventive Medicine and Public Health
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• 제43권5호
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• pp.377-386
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• 2010

Objectives: This study was carried out for the purpose of evaluating the blood mercury concentration of the residents of Busan, Korea, as well as the relationship between the mercury concentration and the pattern of fish consumption along with other epidemiological factors. Methods: Two hundred ninety-three subjects (147 men and 146 women), who were aged 40 years or more, were recruited into this study between June and October 2009. The mean age of the subjects was 54.3 years (with a range of 40-70 years). Mercury concentrations in blood samples were measured using a gold-amalgam collection method. Results: The geometric mean concentration of mercury in the total subjects was $8.63\;{\mu}g/L$ [range: $1.48{\sim}45.71\;{\mu}g/L$]. The blood mercury concentration of the men ($9.55\;{\mu}g/L$) was significantly higher than that of the women ($7.76\;{\mu}g/L$). The blood mercury concentration of those who eat fish more than 4 times per week was higher than others, and was statistically significant (male p = 0.0019, female p = 0.0002). According to the multiple analysis, the blood mercury concentration was significantly affected by the consumed fish but other epidemiological factors were not related. Conclusions: It was found that the subjects who have consumed a large amount of fish may have high blood mercury concentration. It appears that fish consumption can influence blood mercury concentration. Therefore, guidelines for fish consumption that will decrease blood mercury concentration might be necessary in Korea.

• 대한기계학회논문집B
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• 제35권11호
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• pp.1219-1227
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• 2011

최근 생활 환경의 변화로 혈관계 질병으로 고통 받는 사람들이 늘어가고 있다. 이에 따라 질병을 치료하기 위해 여러 가지 시술을 하게 되는데 있어서 혈관의 역학적인 분석과 해석이 확보되어야 한다. 본 논문에서는 초탄성 이론을 기초로 하여 탄성 대변형에서의 혈관의 역학적인 거동에 대해 알아 보았다. 이를 통하여 정상혈압과 고혈압일 때 혈관에 작용하는 응력과 열림각으로 나타낼 수 있는 잔류 응력의 효과가 각 방향 응력분포에 미치는 영향에 대해 연구하였다. 그 결과 잔류응력 효과를 적용시켰을 때 혈관 벽내에 작용하는 최대응력은 잔류응력 효과가 없을 경우와 비교하여 약 50%응력 감소가 나타남을 확인할 수 있고, 고혈압의 경우 정상혈압일 때보다 2배정도의 큰 응력이 혈관벽에 작용함을 확인 할 수 있었다.

• 한국융합학회논문지
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• 제10권2호
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• pp.67-73
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• 2019

혈압측정은 오랜 시간동안 외부압력을 이용하여 혈관 압력 대응값으로 계산해왔다. 최근 측정 장비의 소형화와 의료네트워크 기술의 발전으로 개인 건강관리시스템의 활성화로 인해 간단한 센서로 혈압을 연속적이며 실시간 측정이 가능한 환경을 요구하고 있다. 본 연구에서는 광전용적맥파를 적용하고 맥파전달시간을 이용하여 혈압을 추정하고자 한다. 기존 방식은 신체 변수값 등으로 개인 오차를 줄여 측정하는 알고리즘을 사용하고 있으나, 광전용적맥파의 분석과 맥파전달시간의 적용방법에 따라 정확도가 떨어진다. 본 연구에서는 기존 수축기 혈압을 이용하여 혈압을 유추하는 융합적인 방법을 선택하여 적용하였다. 그리고 광전용적맥파 자체로만 혈압 추정이 가능하게 구성하여 초소형 혈압측정시스템을 만드는데 필요한 융합알고리즘을 제공하고자 하였다. 그 결과 수축기혈압과 광전용적맥파의 최대, 최소 주기간격을 이용하여 혈압추정 융합 알고리즘의 가능성을 상관관계로 분석하였다.