• Title/Summary/Keyword: Physiological flow

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Prediction of the Concentration of Diphenylhydantion in the Brain Using a Physiological Pharmacokinetic Hybrid Model

  • Song, Sae-Heum;Shim, Chang-Koo;Lee, Min-Hwa;Kim, Shin-Keun
    • Archives of Pharmacal Research
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    • v.13 no.3
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    • pp.221-226
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    • 1990
  • A physiological pharmacokinetic hybrid model was developed in order to predict the disposition kinetics of diphenylhydantoin (DPH) in the brain from the plasma conentration data of DPH. The model was constructed under the assumptions of well-stirred, plasma flow-limited and lienar tissue diposition kinetics of DPH. DPH was administered intravenously to the rats at a dose of 10 mg/kg together with/without sodium salicylate (SA;10 mg/kg) and the DPH concentrations in the plasma and brain were determined. Plasma protein binding of DPH concentrations in the plasma and brain were determined. Plasma protein binding of DPH was also determined using equilibrium dialysis technique. Then the model was tested for its predictability of DPH concentrations in the brian from the plasma data of DPH. It was found that the predicted values of DPH concentrations in the brian were in fair agreement with the experimental values in the rats of both treatments. The 2-fold increase in the brain concentration of DPH by SA-coadinistration was predicted well from the plasma concentration and plasma free fraction ($f_p$) data of DPH using the model. Therefore, the hybrid model was concluded to be very useful for the prediction of the concentrations of DPH in the brain from the plasma concentration data. Finally, DPH concentrations in the human brian was calculated using this model from plasma DPH data in the literature, yet the scale-up of this model to the human is not convinced.

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Performance of Holstein cows subjected to different cooling sessions during subtropical summer

  • Bah, Musa;Javed, Khalid;Pasha, Talat Naseer;Shahid, Muhammad Qamer
    • Animal Bioscience
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    • v.35 no.11
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    • pp.1800-1807
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    • 2022
  • Objective: This study aimed to determine the effect of different cooling sessions (CSs) as a water conservation strategy on physiological, and production responses and welfare in Holstein Friesian cows during subtropical summer in Pakistan. Methods: Twenty-one cows were subjected to three CS in a completely randomized design. The treatments were: i) eleven hours continuous cooling with sprinklers - control (CNT), ii) four CS, and iii) two CS. The CNT represented the practices of the commercial dairy farms in the area, while the other CSs were used as water reduction strategies. Each CS lasted for 1 h with a 12 min cycle (3 min water on and 9 min off) with a sprinkler flow rate of 1.25 L/min. Results: The average temperature humidity index of the shed and the outside open area were 81.9 and 82.5, respectively. The results showed that both physiological responses were highest in the 2CS group followed by the CNT and the 4CS (p = 0.001). The CNT and 4CS groups had similar milk yield (p = 0.040). The 4CS group had more lying and eating times than the CNT and 2CS groups (p = 0.000). The cortisol level in the 2CS group was 2.0 and 2.2 ㎍/dL more than the CNT and the 4CS groups, respectively (p = 0.000). Conclusion: In conclusion, the 4CS was more efficient in cooling the cows and had better welfare, as it yielded similar milk yield, and better physiological responses than the CNT despite using 90% less water.

Experimental Study of CheonghunHwadam-tang on the Cerebral Blood Flow in Rats (청훈화담탕이 국소뇌혈류량에 미치는 실험적 연구)

  • Kim Cheon Joong;Cho Su In;Jeong Hyun Woo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.16 no.2
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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.

The experimental research on periodic airflow in human nasal cavity (비강내 주기유동장의 실험적 해석에 관한 연구)

  • Kim, Sung-Kyun;Son, Yeong-Rak;Sin, Seok-Jae
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.1687-1692
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    • 2004
  • Airflow in the nasal cavity of a normal Korean adult is investigated experimentally by tomographic PIV measurement. Knowledge of airflow characteristics in nasal cavities is essential to understand the physiology and pathology aspects of nasal breathing. Several studies have utilized physical models of the healthy nasal cavity to investigate the relationship between nasal anatomy and airflow. All of these researches on nasal airflow are under the condition of constant flow-rate. In this study, nasal cavity flow with the physiological period is investigated by tomographic PIV, for the first time. A pumping system that can produce the periodic flow is created. Thanks to a new method for the model casting by a combination of the rapid prototyping and curing of clear silicone, a transparent rectangular box containing the complex nasal cavity can be made for PIV. The CBC PIV algorithm is used for analysis. Phase-averaged mean and RMS velocity distributions are obtained for inspirational and expiration nasal airflows. The comparison with the constant flow case is appreciated. There exist many flow patterns depending on each phase.

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A Simplified Method for the Local Blood Flow Determination in Rats and Rabbits by means of $^{86}Rb$ ($^{86}Rb$을 이용한 국소 혈류량 측정편법)

  • Sung, Ho-Kyung;Koh, Joo-Hwan;Moon, Kwang-Nam;Lee, Jang-Kyu
    • The Korean Journal of Nuclear Medicine
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    • v.5 no.2
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    • pp.65-71
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    • 1971
  • A simplified method for the local blood flow determination by means of $^{86}Rb$ was developed in rats and rabbits. $^{86}Rb$ in the form of chloride mixed with physiological saline was intravenously injected. The doses were $10{\mu}Ci$ for rats and $100{\mu}Ci$ for rabbits, which were injected in less than 5 seconds. The rats were sacrificed after 30 seconds, and the rabbits at the intervals of 10, 20, 40 and 60 seconds, by decapitation or rapid intravenous injection of 3 to 5ml of saturated KCI. After bleeding, the organ and tissue samples, e.g. lungs, renal cortex, jejunum and skeletal muscle were quickly removed. The $^{86}Rb$ uptake in 1 gram of the organs and tissues were measured. On the basis of uptake value, administered dose and body weight, the local blood flow was calculated. Following were the results: 1. The uptake values of $^{86}Rb$ in the above organs and tissues of rats were different from other previous reports, in which the large rats were used. It appears, therefore, that the correction on the basis of body weight is necessary. 2. The uptakes of $^{86}Rb$ in the above organs and tissues of rabbits remained rather stationary within 20 to 40 seconds. 3. The local blood flow in the above organs and tissues were calculated from $^{86}Rb$ uptake in per cent dose per 1 gram tissue for 200 gram body weight. The formula could be applied not only to the rabbits but to the rats. 4. The present method could be applied to the comparison of the local blood flow between the various organs and tissues of the control and experimental animals.

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Comparison of Peripheral Blood Flow in Post-Stroke Hemiparetic Patients and Normal Person with Doppler Ultrasonography (도플러 초음파 기기를 이용한 편측 부전마비성 뇌졸중 환자와 정상인의 말초 혈류 비교 연구)

  • Han, Deok-Jin;Bang, Chang-Ho;Kim, Sergey;Bae, Young-Min;Shin, Sae-Ron;Yang, Chung-Yong;Lee, In
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.23 no.6
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    • pp.1491-1496
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    • 2009
  • Stroke is usually associated with the cerebral blood flow of the central nervous system. However, studies concerning the effects of neurologic sysmptoms induced from stroke on the peripheral blood flow has not taken place sufficiently. To ascertain the feasibility of a blood flow meter adopting to use doppler ultrasonogrphy, under the prospect that hemiparesis induced from stroke may have effect on the peripheral blood flow, the peripheral blood flow velocity was observed. The control group made up of healthy people without any factors capable of effecting the peripheral blood flow velocity, and patient group which consist of hemiparetic people induced from stroke, were recruited. Volumes of recruitment are 21 persons in the patient group, and 29 persons in the control group, but the final numbers of people are 17 and 21 respectively because of the inconsistancy in the method of the test. The non-invasive method of Doppler effect of Ultrasound was used to measure the blood flow velocity. The blood flow velocity in the peripheral part of left and right fourth fingers:dorsal branches of proper palmar digital artery to dorsum of distal phalanges, was measured in the control group and patient group through Doppler Ultrasound. In comparison of the control group and the patient group, the systolic blood flow velocity from the peripheral part of the upper extremity was lower in the patient group than that of the control group. According to such results, it is concluded that hemiparesis induces the reduction of the peripheral blood flow velocity in the systolic phase.

Rheographic View of the Change in the Renal Blood Flow in Acute Hemorrhage (Rheogram으로 본 실혈시 신장혈액유통 변화)

  • Chang, Se-Gu;Shin, Dong-Hoon
    • The Korean Journal of Physiology
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    • v.5 no.1
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    • pp.59-69
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    • 1971
  • Studies were undertaken on the changes in the renal blood flow by relating them with the alterations in the amplitudes in the rheogram of rabbits. The changing pattern of the electrical conductivity was recorded by means of the needle electrodes inserted into the kidney and the surrounding aluminium foil which was grounded. The Impedance Rheograph manufactured by the Narco Company was used. The small artifact which persisted after ligation of the renal vessels was subtracted from the value obtained in each pulsatile wave in the rheogram. The animals were nembutalized intravenously, 30 mg/kg. A plastic canule was inserted into the carotid artery and the arterial blood pressure was monitored continuously with the pressure transducer connected to the physiograph. Stepwise bleedings were performed on the animal. The first bleeding was between 13 to 18 ml in the amount, and it was folowed by consecutive hemorrhages, 5 or 10 ml each time. The total amount of bleeding was summed as much as 1.5-2% of the body weight. Two minutes fter each bleeding th arterial blood pressure, ECG and the rheogram were taken. That was the necessary time to obtain the stabilized picture of each parameter. After closing the bleeding process, the shed blood was retransfused into the animal and the response in the renal blood flow was observed as well as the arterial blood pressure. Particularly the presence or absence of the autoregulatory mechanism in the situation of the hemorrhage was also studied. The results obtained were as follows: 1. In 7 cases out of 22, that was about one third of the total number of experiments, the autoregulatory mechanism of the renal blood flow persisted even in acute hemorrhage, and the decreases in the renal blood flow were less than 10% of the control values even when the arterial blood pressure dropped to 66-87% of the original value obtained before the bleeding. 2. Because of the stepwise bleeding the exact blood pressure at which the renal blood flow reduced as much as one third of the control value could not be obtained. However, the results revealed that the approximate pressure, expressed as percentage of the control value, was 50-60% in 3 cases, 61-70% in 4 cases and 71-80% in 8 cases. In one case the decrease in the renal blood flow exceeded one third of the control value before the pressure dropped to 80% of the control. 3. In 19 cases the decreases in the renal blood flow exceeded one half of the control values by hemorrhage. Then the arterial blood pressure revealed less than 40% of the control value in 6-cases. In 2 cases the pressure was 51-60% of the control pressure. In 5 cases the range of bleed pressure was 61-70%, and in e remaining 6 cases the pressure ranged from 71 to 80% of e control value. 4. Out of 15 cases of retransfusion after definite decreases in the renal blood flow loller·ing the hemorrhage, 9 cases restored their renal blood flow. On the contrary 6 cases showed low values even when the shed blood was retransfused. 5. Theories concerning the mechanism of the autoregulation of the renal blood flow were reviewed for the purpose of explanation of the results obtained. However, there are much to be done before greater satisfaction

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The Study of Compatibility for Method of Analysis of Nonlinear Characteristics of Blood Flow of Peripheral in Rabbit (토끼에 있어서 말초혈류운동의 비선형특성분석방법의 적합성에 관한 연구)

  • 남상희;최준영;이상훈
    • Progress in Medical Physics
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    • v.8 no.1
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    • pp.75-82
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    • 1997
  • The human physiological systems are so complex and irregular dynamics. Dynamics of peripheral blood vessel, in particular, have quite sensitive and complex. Before, the linear analytic method have been used to analyze the system. But, the method have many problems to predict the following results. In the other hand, the nonlinear analytic method, chaotic time series analysis method, is suitable for measuring complex, vary system. In this study, the scalar data of the blood flow of peripheral blood vessel of rabbits, in accordance with injection of glucose, was obtained and redefined as multi-dimensional vectors, with time-series analytic methods. This study also intended to confirm that the peripheral blood flow is chaotic dynamics and evaluate the availability of non-linear analytic method. As a result, the existing FFT, and mean could show the difference of blood flow of peripheral blood vessel by injection of glucose, but the nonlinear analytic method could show the definite difference. The hemodynamics is a chaotic phenomenon.

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Wireless Telemetry of an Oscillating Flow using Mesoscale Flexible Cantilever Sensor (메소스케일 유연 외팔보 센서를 이용한 진동유동의 무선 계측)

  • Park, Byung Kyu;Lee, Joon Sik
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.37 no.5
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    • pp.495-501
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    • 2013
  • This paper describes a flexible wireless telemetering system using a mesoscale cantilever sensor, which is microfabricated with a patterned thin Ni-Cu foil on a resin substrate. The dynamic validation of the sensor has been conducted in a flow. The wireless telemetry is used to obtain data regarding the oscillating flows. It is shown that the sensor is nearly independent of the environmental temperature and is suitable for application to primary healthcare and diagnostic devices. It can be easily integrated with other modules for measuring physiological parameters, e.g., blood pressure, oxygen saturation, and heart rate, to increase the convenience and reliability of diagnosis. The precision and reliability of the sensor are also dependent on the design of the analog front-end and noise reduction techniques. It is shown that the present system's minimum interval between packet transmissions is ~16 ms.

Mechanism on the Changed-Regional Cerebral Blood Flow and Mean Arterial Blood Pressure by CheonghunHwadam-tang Adding Schiznepetae Herba in Rats (청훈화담탕가형개로 인해 변동된 국소뇌혈류량 및 평균혈압의 작용기전)

  • Min Byeng Il;Im Gwang Mo;Jeong Hyun Woo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.16 no.4
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    • pp.701-706
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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. CHTS was CHT adding Schizonepetae Herba. The effects of CHTS on the cerebral blood flow and blood pressure is not known. The purpose of this Study was to investigate effects of CHTS on the regional cerebral blood flow(rCBF) and mean arterial blood pressure(BP), action-mechanism of CHTS-induced changed-rCBF and BP. The changes of rCBF and BP was determinated by Laser-Doppler Flowmetry(LDF). The results were as follows ; CHTS extract was increased significantly rCBF in a dose-dependent, but was not changed BP compared with CHTS non-treated group. Pretreatment with propranolol, indomethacin and methylene blue were inhibited CHTS induced increase of rCBF, propranolol(all CHTS-treated group) and indomethacin(CHTS 0.01 mg/kg) of them were significantly decreased. Pretreatment with propranonol and indomethacin were inhibited CHTS induced increase of BP, but pretreated with methylene blue was significantly accelerated BP in high dosage. This results suggest that CHTS increased rCBF by dilating pial arterial diameter and the action of CHTS is also mediated by adrenergic β -receptor and cyclooxygenase.