• Title/Summary/Keyword: Blood flow rate

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Spectral Element Modeling for the Blood Flow through Artery (동맥 유동해석을 위한 스펙트럴 요소의 개발)

  • Jang, In-Joon;Seo, Bo-Sung;Lee, U-Sik
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2007.05a
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    • pp.383-386
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    • 2007
  • As the blood flow characteristics have been recognized to be closely related to various cardiovascular diseases, it is very important to predict them accurate enough in an efficient way. Thus, this paper proposes a one-dimensional spectral finite element model for the human blood vessels. The spectral finite element model is formulated in the frequency-domain by using the exact frequency dependent shape functions and applied to an ascending aorta.

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NUMERICAL STUDY ON BLOOD FLOW CHARACTERISTICS IN A ARTERIOVENOUS GRAFT WITH DELIVERED DOSE DURING HEMODIALYSIS (인조혈관 동정맥루의 혈액 투석량에 따른 인조혈관 내부 유동 특성에 관한 수치해석 연구)

  • Kim, J.Y.;Ro, K.C.;Ryou, H.S.
    • Journal of computational fluids engineering
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    • v.16 no.4
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    • pp.84-91
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    • 2011
  • Hemodialysis is essential for patients with end stage renal failure. It is important to improve the patency rate and to minimize occurrence of the stenosis. Also, the blood flow to the artificial kidney can affect the blood flow characteristics through arteriovenous graft. Thus, the delivered dose are important factors for analyzing hemodynamic characteristics during hemodialysis access. In this study, the numerical analysis was performed for the effect of the delivered dose during hemodialysis access on the blood flow through the graft. As a result, The adverse pressure gradient occurred in case of a larger delivered dose through a catheter than standard dose and the flow instability increased. Also the circulation flow appeared largely at anastomotic site of the vein when the delivered dose was exceeded about half blood flow of inlet blood flow.

Numerical Study on Blood Flow Characteristics in a Arteriovenous Graft with Delivered dose During Hemodialysis (혈액 투석 시 주사침에서의 투석량에 따른 인조혈관 내부 유동 특성에 관한 수치해석 연구)

  • Kim, J.Y.;Ro, K.C.;Ryou, H.S.
    • 한국전산유체공학회:학술대회논문집
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    • 2011.05a
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    • pp.469-476
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    • 2011
  • Hemodialysis is essential for patients with end stage renal failure. It is important to improve the patency rate and to minimize occurrence of the stenosis. Also, the blood flow to the artificial kidney can affect the blood flow characteristics though arteriovenous graft. Thus, the delivered dose are important factors for analyzing hemodynamic characteristics during hemodialysis access. In this study, the numerical analysis was performed for the effect of the delivered dose during hemodialysis access on the blood flow through the graft. As a result, The adverse pressure gradient occurred in case of a larger delivered dose through a catheter than standard dose and the flow instability increased. Also the circulation flow appeared largely at anastomotic site of the vein when the delivered dose was exceeded about half blood flow of inlet blood flow.

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Effects of Crude Saponin and Saponin-free Fraction of Korea Red Ginseng on the Skin and Cerebral Blood Flow in the Rats (백서의 피부 및 뇌혈류에 미치는 고려홍삼 사포닌 및 비사포닌의 영향)

  • Kim, Shin-Hee;Kim, Cuk-Seong;Park, Jin-Bong;Han, Chan-Soo;Kim, Kwang-Jin;Kim, Shin-Hye;Kim, Se-Hoon;Nam, Ki-Yeul;Jeon, Byeong-Hwa
    • Journal of Ginseng Research
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    • v.26 no.3
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    • pp.132-138
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    • 2002
  • To study the effect of Korea red ginseng (KCG) on the skin and cerebral blood flow, we evaluated the change of skin perfusion rate and cerebral perfusion rate after the intravenous, intraperitoneal, and oral administration of crude saponin (CS) and saponin-free fraction (SFF) of KRG in the rats. The change of skin perfusion rate and cerebral perfusion rate was measured laser doppler flowmetry. The intravenous injections of CS or SFF of KRG and intraperitoneal injection of SFF of KRG did not change the relative skin and cerebral blood flow in the rats. When the rats were treated by the intraperitoneal injection of CS of KRG, relative cerebral blood flow was significantly increased with a time-dependent manner, however, relative skin blood flow was not influenced by the them. Oral administration of CS of KRG slightly increased skin blood flow in the rats. Also, the change of cerebral blood flow by transient bilateral carotid arterial clamp in the CS-treated rats was significantly decreased, compared with control groups. From the above results, it was suggested that Korea red ginseng have a increasing property of cerebral blood flow in the rats.

The Effect of Sun Ginseng on Hemodynamics and Body Temperature in Healthy Young Men

  • Lee, Jeeh-Wan;Cho, Jung-Ah;Ki, Chan-Young;Park, Jeong-Hill;Park, Man-Ki
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.317.2-318
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    • 2003
  • The current study was performed to observe the effect of Sun Ginseng (SG) on hemodynamics such as blood flow rate (BF), blood flow velocity (BV), heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP), and body temperature (BT) in healthy young men. This is a randomized, single-blind study observed during 6 hrs after orally single administration of SG. (omitted)

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Implementation of Non-Invasive Cerebral blood Increasing Platform using PI (혈류지수를 이용한 비침습적 대뇌혈류증가 장치의 구현)

  • Kwon, Seong-tae;Lee, Jean;Kim, Young-kil
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.9
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    • pp.1761-1770
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    • 2017
  • Treatment for cerebral blood flows is one of the most important treatments for cerebral infarction. There is a concern that the increasing number of cerebral blood flow treatments can cause multiple complications as it is invasive. To compensate for these problems, recently non-invasive cerebral blood flow increases have emerged. However, the current implementation of the non-invasive cerebral blood flow sensor raises the question of speed and accuracy. In this theses, the system aims to minimize the final cortical damage to the cerebrum by implementing a system in a completely different manner to complement the disadvantages of the existing non-invasive cerebral blood flow device. The system measure the PI of the limbs while simultaneously pressing limbs. Blood flow rate is carried out indirectly by increasing blood flow to peer pressure through the limbs in which the PI eips below a certain level. This can be used selectively in patients to increase blood flow.

The Blood Disappearance Rate of $^{198}Au$-Colloid and Changes of Hepatic Blood Flow During Position Change in Normal Persons and in Patients with Various Hepatic Diseases (정상인(正常人) 및 각종(各種) 간질환(肝疾患) 환자(患者)에서 $^{198}Au$교질(膠質)의 혈중소실율치(血中消失率値)와 체위변동(體位變動)에 따른 간혈류량변화(肝血流量變化)에 관한 연구(硏究))

  • Cho, Bo-Yeon;Hong, Kee-Suck;Koh, Chang-Sun;Lee, Mun-Ho
    • The Korean Journal of Nuclear Medicine
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    • v.11 no.1
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    • pp.33-37
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    • 1977
  • To evaluate the diagnostic significance of the blood disappearance rate of $^{198}Au$-colloid and to evaluate the change of hepatic blood flow during position change from supine to erect, we measured the half time of blood disappearance rate of $^{198}Au$-colloid using external counting method in 94 normal persons and in 77 patients with various hepatic diseases. The results obtained were as follows: 1. In normal control, the mean blood disappearance half time of $^{198}Au$-colloid in supine position was $2.7{\pm}0.4$ minutes. There was no significant difference of hepatic blood flow in age and sex. 2. In acute hepatitis, chronic hepatitis and hepatic cirrhosis, the mean blood disappearance half times in supine position were $3.0{\pm}0.45,\;3.5{\pm}0.74,\;7.2{\pm}3.6$ minutes respectively. The hepatic blood flow of the patients with chronic hepatitis and hepatic cirrhosis were significantly decreased than that of normal control. 3. In the normal control and acute hepatitis, the decreaces of the hepatic blood flow during the position change from supine to erect were 27.7% and 22.6% respectively.

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Effects of bee venom acupuncture on heart rate variability, pulse wave, and cerebral blood flow for types of Sasang Constitution (봉약침 자극이 사상체질별 건강인의 심박변이도, 맥파, 뇌혈류에 미치는 영향)

  • Lee, Sang-Min;Kim, Koo;Oh, Seung-Yun;Kwon, Young-Mi;Joo, Jong-Cheon
    • Journal of Pharmacopuncture
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    • v.12 no.1
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    • pp.35-42
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    • 2009
  • 1. Objectives To evaluate effects of bee venom acupuncture on cardiovascular system and differences according to each constitution. 2. Methods Heart rate variability, pulse wave and the velocity of cerebral blood flow were measured before bee venom acupuncture(BVA), right after and after 30 minuets, had been applied to 20 subjects. 3. Results 1. BVA did not have effects on measurement variables of heart rate variability. 2. BVA had effects on pulse wave, showing total time, radial augmentation index up and height of percussion wave, time to percussion wave, sum of pulse pressure down. 3. BVA did not have effects on the cerebral blood flow velocity when considering not Sasang Constitution. 4. Considering Sasang Constitution, BVA demonstrates different responses in time to preincisura wave, mean blood flow velocity, peak systolic velocity and end diastolic velocity. 4.Conclusion From those results, the following conclusions are obtained. Cause BVA alters pulse wave and makes differences in the cerebral blood flow velocity according to Sasang Constitution. Various methods of BVA treatment are needed considering Sasang Constitution.

The Clinical Study about Difference of Cerebral Artery Blood Flow Velocity according to the Sasang Constitution (사상체질별(四象體質別) 뇌혈류(腦血流) 변화(變化)에 대한 임상적(臨床的) 고찰(考察))

  • Ann, Taeck-Won
    • Journal of Haehwa Medicine
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    • v.11 no.1
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    • pp.1-9
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    • 2002
  • 1. Purpose We inquire into difference of blood flow velocity according Sasang Constitution. 2. Method We selected observation group that they are 251 patients among of the patients who are had a medical early examination of stroke. We classified observation group by Sasang Constitution and compared each of measured blood flow velocity by TCD. 3. Result 1) We found out that Taeumin is highest in fat rate, height and blood pressure. 2) Blood flow mean velocity of MCA is not found out significant difference by Sasang Constitution. But, Taeumin is found out highest in left and right. 3) Taeumin is found out that blood flow velocity of Siphon sinus ICA is highest.

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Clinical Observation on Heart Rate Variability and Peripheral Blood Flow by Doppler Ultrasound in Healthy Subjects Stimulated by Cold Stress (정상인의 한냉자극에 대한 심박변이도 및 도플러 초음파 혈류계를 이용한 말초 혈류관찰)

  • Lim, Sung-Keun;Lee, Sang-Hoon;Bae, Young-Min
    • The Journal of Korean Medicine
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    • v.31 no.2
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    • pp.114-123
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    • 2010
  • Objectives: This study was performed to investigate the effect of cold stress on heart rate variability and peripheral blood flow by Doppler ultrasound in healthy subjects. Methods: We classified the subjects by their Yin or Yang tendency using a Yin-Yang questionnaire. Cold stress was taken on the left hand of subjects for 10 seconds. Heart rate variability and peripheral blood flow were measured on the right radial artery before and after cold stress. Results: The Yang tendency group showed a significant decrease of heart rate after cold stress which was not seen in the Yin tendency group. The Yang tendency group showed a decrease of LF, total power, and increase of HF after cold stress, while the Yin tendency group showed the opposite. However, there were no statistically significant differences of heart rate variability analysis between the results of the two groups before and after cold stress. Recovery time of blood flow velocity by ultrasound Doppler was significantly different between the Yin and Yang tendency groups after cold stress. Conclusion: These results suggest that people with Yin or Yang tendency may show different responses in the autonomic nervous system. Further modified studies may include the responses to various manipulation techniques in acupuncture treatment and the individual responses according to pattern identification in traditional Korean medicine.