• 전자공학회논문지SC
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• 제38권1호
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• pp.45-52
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• 2001

PISA 방법은 주로 승모판에서 역류하는 혈류량을 측정하기 위해 사용되고 있다. 이 방법은 PISA isotach의 기하학적 모양에 대한 모델링에 관한 것이다. PISA의 일반적인 유동모델은 isotach의 표면이 수식적으로 반구이거나 비반구임을 가정하여 계산된 것이지만, 본 논문에서는 영역기반방법으로 isotach를 추정한 후, 타원체의 높이에 기초한 실제적인 표면분할 유동모델을 이용하여 유체량을 추정하였다. 제안한 밥법을 평가하기 위해, $30cm^3/sec-60\;cm^3/sec$의 실제 유량을 가지는 동적인 180개의 유동영상에 대해서 기존 방법들과 비교하였다. 실험한 결과, 반구 유동모델의 유체량 평균이 $29\;cm^3/sec$로 실제 유체량 평균보다 35%정도 적게 추정을 하였고, 제안한 방법의 평균은 $45\;cm^3/sec$으로 비반구 유동모델의 평균과 같았고, 유체량 변화파형도 유사한 결과를 가짐을 알 수 있었다.

• 대한의용생체공학회:의공학회지
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• 제26권5호
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• pp.337-341
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• 2005

Blood pulsation has been reported to have an advantageous effect on extracorporeal blood circulation. However, the study of pulsatile blood flow in renal replacement therapy is very limited. The in-vitro experimental results of pulsatile blood flow on ultrafiltration, when compared with the conventional roller pump, are described in this paper. Methods: Blood flow rate (QB) and transmembrane pressure (TMP) were considered as regulating factors that have an influence on ultrafiltration. Experiments were performed under the condition of equal TMP and OB in both pulsatile and roller pump groups, Several kinds of hollow fiber dialyzers were tested using distilled water containing chemicals as a blood substitute. Mean TMP (mTMP) varied from 10 to 90mmHg while the QB was 200ml/min. Results: Ultrafiltration rate (QUF) was found to be linearly proportional to TMP, whereas QB had little influence on QUF. In addition, QUF was higher in the pulsatile group than the roller pump group at the identical TMP. Conclusion: In the controlled test, QUF increased solely as a consequence of blood pulsation, which implies that the pulse frequency represents an additional and important clinical variable during renal replacement therapy.

• 대한핵의학회지
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• 제3권1호
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• pp.1-12
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• 1969

Liver functions in diffuse parenchymal liver disease such as cirrhosis of the liver depend largely on the effective hepatic blood flow rather than on the individual cell functions. Clinical methods of measuring the hepatic blood flow were developed recently by the application of colloidal disappearance rate. In order to correlate the radiogold disappearance rate to conventional biochemical liver function tests, 21 normal subjects and 80 cases of cirrhosis of the liver were studied with both methods. The results are summarized as following: 1. The validity of external counting method to measure the blood disappearance rate of colloidal radiogold was confirmed by in vitro counting of the serial blood samples. 2. The blood disappearance rate of collidal radiogold was essentially the same. as the liver uptake rate of colloidal radiogold in normal and cirrhotic subjects with various degrees of functional disturbance. And it seemed there was no serious extrahepatic removal of the colloidal radiogold. 3. The disappearance rate of colloidal radiogold was not significantly changed by the posture change, but was enhanced by ingestion of 500 ml of water. 4. The disappearance rate of colloidal radiogold was not influenced by single dose of Telepaque, while BSP retention was increased after Telepaque. 5. The mean disappearance half time of colloidal radiogold in normal subjects was $2.49{\pm}0.391$(S.D.) minutes. The mean normal disappearance rate constant (K value) was $0.285{\pm}0.0428$(S.D.)/minute. 6. The colloidal radiogold disappearance half time was abnormally prolonged (over 3.2 min.) in $87.7{\pm}3.68$(S.D.) % of cirrhotic subjects. 7. In patients of liver cirrhosis the blood disappearance rate of colloidal radiogold correlated well to serum albumin and globulin levels and BSP retention which were considered to reflect functions of hepatic parenchymal cells. There was, however, no correlation between colloidal disappearance rate and thymol turbidity test, serum glutamic pyruvic transaminase, and serm alkaline phosphatase activities. The latters were considered to be associated with the activity of liver disease.

• 동의생리병리학회지
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• 제28권6호
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• pp.607-613
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• 2014

In a previous study, we have shown that mulberry leaves (Mori Folium) extract MFE) and its compounds have the antioxidant effect in human red blood cells. However, the possible effect of MFE and its compounds on improvement of blood flow were not reported. Therefore, the aim of this study is to investigate the effects of MFE and its compounds on improvement of blood flow in a rat model of topical ferric chloride ($FeCl_3$)-induced carotid artery damage. The $FeCl_3$ treatment seriously damaged the carotid artery: the walls of the artery, blood flow rate, blood vessel diameter, blood vessel area and blood flow amount. However, administration of MFE or its compound has ameliorated the blood flow and suppressed thrombus in blood vessels. Moreover, the concentrations of serum total cholesterol, triglycerides, and LDL cholesterol in the MET and its compound groups were remarkably reduced in comparison to the control group, and HDL cholesterol concentration was higher in the MET and its compound groups than in the control group. These results suggest that MFE and its compounds ameliorate the thrombosis against blood vessel damage.

• 대한한방내과학회지
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• 제20권1호
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• pp.222-231
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• 1999

Uwhangchungsimwon(UC) has been used in the treatment of a wide variety of conditions including stroke, hypertension, arteriosclerosis, autonomic imbalance, mental instablity, etc in Korean traditional hospitals, In particular it is often initialy chosen for emergency care of acute stroke. The aim of this study was to evaluate the effect of UC on cerebral hemodynamics. Using transcranial Doppler ultrasound, we studied changes of mean flow velocity and pulsatility index(PI) of middle cerebral arteries (MCAs) from 11 health young volunteers who were administrated with 1 pill UC and 11 health controls who were not. We obtained hypercapnia with breath-holding and evaluated cerebrovascular reactivity with breath-holding index(BHI). Systolic blood pressure, diastolic blood pressure, and heart rate were measured using ambulatory blood pressure monitoring(ABPM). In UC administration group, the evaluation was performed during basal condition. and repeated at 20, 40, and 60 min after administration. In controls, the evaluation was performed at corresponding time intervals. Mean flow velocity in middle cerebral artery, systolic blood pressure, diastolic blood pressure, and heart rate did not change during the observation period and were not different between these two groups. However, administration of UC was associated with decreases in PI by $3.6{\sim}12.4%$ in BHI by $17.9{\sim}24.8%$ compared with pre-administration period. Decreases in PI and BHI with UC were significantly different compared with control group (p<0.05). These results indicate that UC decreases PI and BHI in cerebral artery, which is due to a dilation of cerebral resistance vessels.

• 동의생리병리학회지
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• 제16권2호
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• pp.316-321
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• 2002

CheonghunHwadam-tang(CHT) have been used in oriental medicine for many centuries as a therapeutic agent of vertigo by wind, fire and phlegm. CheonghunHwadam-tangGamypang(CHTG) was CHT adding Aurantii Fructus(AF), Gastrodae Rhizoma(GR). The effects of CHT on the cerebral blood flow and cardiacvascular system is not known. The purpose of this Study was to investigate effects of CHT and CHTG on the regional cerebral blood flow(rCBF), mean arterial blood pressure(BP), cardiac muscle contractile force(CMF), heart rate(HR). The changes of cerebral blood flow and movement of cardiacvascular system(BP, CMF, HR) was determinated by Laser-Doppler Rowmetry(LDF). The results were as follows; 1. CHT extract increased rCBF, but decreased BP, HR in a dose-dependent manner. 2. AF extract accelerated rCBF and movement of cardiacvascular system in a dose-dependent manner. 3. GR extract increased significantly rCBF(10.0mg/kg, p<0.05) as well as accelerated BP and rCBF in a dose-dependent manner. 4. CHTG extract increased significantly rCBF(10.0mg/kg, p<0.01) in a dose-dependent, but was not changed movement of cardiacvascular system. This results suggest that CHTG is significantly treated more than CHT in vertigo by wind, fire and phlegm.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2018년도 춘계학술대회
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• pp.188-192
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• 2018

대뇌혈류를 증가 시키는 수술은 뇌경색의 치료방법중 하나이다. 그러나 수술과 같은 침습적인 방법은 환자에게 수술 후유증 또는 부작용을 부담하게 한다. 이러한 침습적인 방법을 보완하기 위해 사람의 혈압을 이용해, 사지에 압박을 가하여 대뇌 혈류를 증가 시키는 비 침습적인 장치도 등장하였다. 그러나 속도와 정확성이 떨어지는 문제점이 제기되었다. 본 논문에서는, 정확한 측정과 측정하는 데에 걸리는 시간을 기존의 장치보다 개선하기 위해, Blood Oxygen Level Sensor를 이용하여, 양팔에 압력을 주면서 각 팔의 Perfusion Index를 측정하여, Perfusion Index가 일정 값 이하로 떨어지는 순간의 75% 압력을 팔에 가하고, 다리에는 팔에서 구해진 압력 값을 이용해 계산하여 얻은 압력을 가한다. 기존의 혈압 측정식 대뇌혈류증가 장치와 같이, 혈류량을 20%이상 증가시킬 수 있고, 또한 측정 시간도 단축한 결과를 얻어 뇌경색 환자에게 선택적으로 사용할 수 있다.

• 한국의류학회지
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• 제17권3호
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• pp.415-427
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• 1993

The purpose of this study was to evaluate the thermoregulatory responses to postures under different environmental conditions and to obtain the basal information for standard clothing weight, indoor climates, and working condition. Two adult female (22.5yrs, 46kg) were participated in this study. The experimental conditions were divided into three groups ; 1) comfort($27{\pm}1^{\circ}C$, $60{\pm}10%$), 2) hot($34{\pm}1^{\circ}C$, $60{\pm}10%$), and 3) cold($21{\pm}1^{\circ}C$, $50{\pm}10%$) condition. The postures performed were as follows; standing, sitting on the chair, sitting on the floor, and supine on the floor. At each condition, subjective sensations, 12 points skin temperature, rectal temperature, total and local sweat rate, pulse rates, blood pressure, skin blood flow rate were measured. The results were as follows : 1. Rectal temperature was high significant among groups in order of supine, sitting on the floor, sitting on the chair, standing posture(p<0.01). 2. Skin temperature was high in part of contact with the surface of the floor or wall and the effect of posture was greater in peripheral temperature than torso temperature. Sitting on the chair and sitting on the floor posture showed higher peripheral temperature than standing and supine posture. And peripheral temperature was lower in supine posture than any other postures. 3. Total and local sweat rate were decreased in order of standing, sitting on the chair, sitting on the floor, supine posture. 4. Pulse rate and disastolic blood pressure were higher in standing posture than supine posture, and there was significant difference between two postures(p<0.001). 5. Blood flow rate of thigh was high in sitting on the chair and sitting on the floor posture and low in standing posture. Blood flow rate of leg was low in standing posture significantly(p<0.01). 6. In comfort and hot condition, temperature sensation and comfort sensation were higher in standing posture and lower in supine posture than any other postures. In cold condition, temperature sensation was lower and comfort sensation was higher in standing and supine posture than any other postures. And supine posture was appeared positive in hot condition and negative in cold condition. From this study, we confirmed the effects of posture on human thermoregulatory responses. Results indicate that even under same conditions and clothing weight, the insulation of clothing will be different to postures.

• 대한물리의학회지
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• 제5권2호
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• pp.255-264
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• 2010

Purpose : The purpose of this study is to analysis effects of resistive exercise on cardiopulmonary fitness and cerebral artery blood flow velocity. Methods : Ten healthy university students had done resistive exercise without aerobic exercise over one year participated resistive exercise group and ten general university students, then were calculated oxygen consumption ($VO_2$) and respiratory exchange rate($VO_2/VCO_2$). After a week, they were measured Transcranial Doppler Ultrasonography(TCD) at moderate exercise(HRmax 50%), maximal exercise (HRmax 100%) for taking cerebral blood flow velocity. Results : In the comparison between groups, resistive exercise group showed significant higher oxygen consumption and lower respiratory exchange than controls(p<0.05). In resistive exercise group, oxygen consumption was significant negative correlation with cerebral artery pulsatory index(p<0.05). but, oxygen consumption was significant positive correlation with systolic blood flow velocity in controls(p<0.05). Conclusions : After considering all the factors, important value in resistive exercise is regular participation and help us increasing contingency response ability.

• 한국정보통신학회논문지
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• 제22권8호
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• pp.1083-1089
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• 2018

대뇌혈류를 증가 시키는 수술은 뇌경색의 치료방법중 하나이다. 이러한 침습적인 방법을 보완하기 위해 사람의 혈압을 이용해, 사지에 압박을 가하여 대뇌 혈류를 증가 시키는 비 침습적인 장치도 등장하였다. 그러나 속도와 정확성이 떨어지는 문제점이 제기되었다. 본 논문에서는, 정확한 측정과 측정하는 데에 걸리는 시간을 기존의 장치보다 개선하기 위해, Blood Oxygen Level Sensor를 이용하여, 양팔에 압력을 주면서 각 팔의 Perfusion Index를 측정하여, Perfusion Index가 일정 값 이하로 떨어지는 순간의 75% 압력을 팔에 가하고, 다리에는 팔에서 구해진 압력 값을 이용해 계산하여 얻은 압력을 가한다. 기존의 혈압 측정식 대뇌혈류증가 장치와 같이, 혈류량을 20%이상 증가 시킬 수 있고, 또한 측정 시간도 단축한 결과를 얻어 뇌경색 환자에게 선택적으로 사용할 수 있다.