• 제목/요약/키워드: Heart control

검색결과 1,765건 처리시간 0.033초

허혈 및 재관류한 흰쥐 심장에 미치는 인삼의 영향 (Effects of Ginseng on Global Myocardial Ischemia and Reperfusion in the Rat Heart)

  • 김병채;김낙두
    • 약학회지
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    • 제32권1호
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    • pp.70-79
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    • 1988
  • The effect of Ginseng on global myocardial ischemia and reperfusion was examined in isolated perfused rat hearts. The Ginseng ethanol extract (100mg/kg/day) was administered orally for 10 days. The rat hearts were removed and perfused at 75cm $H_{2}O$ by the Langendorff method. After 25 min. of global ischemia, the hearts were reperfused. The myocardial contents of adenosine 5'-triphosphate, creatine phosphate, and calcium were assayed. There no differences in ATP levels in all group of normal and Ginseng-treated hearts. Both in non-ischemic and ischemic heart, Ginseng increased significantly tissue creatine phosphate levels compared with control. Whereas, in ischemic-reperfused heart, there was no significant difference. In the control groups, myocardial calcium contents in the ischemic hearts were decreased compared with the non-ischemic hearts. But, in the Ginseng-treated groups, the calcium contents in the ischemic herts were not changed with the nonischemic hearts. Therefore, Ginseng appears to exert its protective effect against ischemic heart condition, not against ischemic-reperfused heart condition, by regulating energy metabolism and maintaing cellular function.

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압반사 제어모델을 이용한 심혈관 시스템의 모델링 및 시뮬레이션 (Modeling and Simulation of the Cardiovascular System Using Baroreflex Control Model)

  • 최병철;엄상희;남기곤;손경식;이영우;전계록
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1997년도 춘계학술대회
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    • pp.165-170
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    • 1997
  • In this paper, we consider the aortic sinus baroreceptor, which is the most representative baroreceptors sensing the variance of pressure in the cardiovascular system(CVS), and propose heart activity control model to observe the effect of delay time in heart period and stroke volume under the regulation of baroreflex in arotic sinus. The proposed heart activity baroreflex regulation model contains CVS electric circuit sub-model, baroreflex regulation sub-model and time delay sub-model. In these models, applied electric circuit sub-model is researched by B.C.Choi and the baroreflex regulation sub-model transforms the input, the arotic pressure of CVS electric circuit sub-model, to outputs, heart period and stroke volume by mathematical nonlinear feedback. We constituted the time delay sub-model to observe sensitivity of heart activity baroreflex regulation model by using the variable value to represent the control signal transmission time from the output of baroreflex regulation model to efferent nerve through central nervous system. The simulation object of this model is to observe variability of the CVS by variable value in time delay sub-model. As simulation results, we observe three patterns of CVS variability by the time delay. First, if the time delay is over 2.5 sec, arotic pressure, stroke volume and heart rate is observed nonperiodically and irregularly. Second, if the time delay is from between 0.1 sec and 0.25 sec, the regular oscillation is observed. Finally, if time delay is under 0.1 sec, then heart rate and arotic pressure-heart rate trajectory is maintained in stable state.

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피톤치드 아로마테라피가 간호대학생의 스트레스, 스트레스 증상 및 심박변이도에 미치는 영향 (Effects of Phytoncide Aromatherapy on Stress, Symptoms of Stress and Heart Rate Variability among Nursing Students)

  • 김철규;조미경;김진일
    • Journal of Korean Biological Nursing Science
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    • 제14권4호
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    • pp.249-257
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    • 2012
  • Purpose: The purpose of this study was to examine the effects of phytoncide aromatherapy on stress, symptoms of stress and heart rate variability among nursing students. Methods: This study is a randomized control-group non-synchronized design. The experimental group (n=31) underwent phytoncide aromatherapy for 2 weeks, while the control group (n=31) received placebo therapy. The data were collected using self-administration questionnaires and measurement of heart rate variability (HRV) and analyzed using SPSS WIN 18.0 program. A p value <.05 was considered statistically significant. Results: Total score of stress, individual score of intrapersonal stress, and score of peripheral manifestations in symptoms of stress in the experimental group were significantly lower than those of the control group. All indices of HRV were significantly different between the two groups. LF norm and LF/HF ratio in the experimental group were significantly lower than those of the control group, and HF norm in the experimental group was significantly higher than that of in the control group. Conclusion: Based on these results, it can be suggested that phytoncide aromatherapy was effective in decreasing stress and peripheral manifestations of stress and changing in HRV among nursing students.

소의 로프보정시 Xylazine 투여가 생체반응에 미치는 영향 (Effect of Xylazine in Cattle under Rope Restrained Conditions)

  • 이동희;배춘식
    • 한국임상수의학회지
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    • 제18권3호
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    • pp.189-194
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    • 2001
  • The aim of this study was to investigate the anti-stress effect of xylazine on rope-restrained stress using cattle. For this study we utilized biotelemetrical methods such as body temperature, heart rate and blood analysis. Twelve cows were divided into two groups as an only rope restrained group (control) and as rope-restrain+xylazine (0.05 mg/kg, IV) treated group (experimental group). Each group was under experimental environments for 24 hours before initiation of stress. The body temperature and the heart rate were checked every 5 minutes for 24 hours in two groups. We found that the core body temperature in the experimental group was higher than that of control group. We also found hat the heart rate in experimental group was significantly lower (p<0.05) than that of control group for 90 minutes after 30 minutes of rope-restrained stress. The level of the plasma cortisol of experimental group was significantly lower (p<0.05) than that of control group for 90 minutes after the rope-restrained stress was given. We performed the blood analysis to know whether rope-restrained stress affects RBC, WBC, hemoglobin, hematocrit, and platelet values or not but we could not find the significant difference between control and experimental groups. These results suggest that the administration of xylazine might partially help to reduce rope-restrained stress in cattle.

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Cardioprotective Effects of Salvia Miltiorrhiza Radix on the Pressure Overloaded Heart Failure Model by Transverse Aortic Constriction-induced Mice

  • Kim, Sae-Won;Jang, Woo-Seok;Baek, Kyung-Min
    • 대한한의학회지
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    • 제37권2호
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    • pp.23-35
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    • 2016
  • Objectives: The objective of this study is to demonstrate the cardioprotective effects of Salvia Miltiorrhiza Radix (SMR) on the pressure overload (PO)-induced heart failure (HF) by transverse aortic constriction (TAC) in C57BL/6 mice through possible antioxidant effects. Methods: The mortality, body and heart weights, antioxidant defense system of the heart and histopathology of heart were analyzed. The obtained results were compared with resveratrol, in which potent cardioprotective effects on TAC mice model were already proved at a dose level of 10 mg/kg by antioxidant effects, as reference in this experiment. Results: Significant increases of mortalities, heart weights, and hypertrophic, lytic and focal fibrotic histological changes in the left ventricles were found with defects of heart antioxidant defense systems - the increases of heart cortex MDA contents, decreases of GSH contents, SOD and CAT activities in TAC control mice as compared with sham vehicle control mice, respectively. However, these HF signs induced by TAC surgery through PO and destroys heart antioxidant defense systems were significantly and dose-dependently inhibited by 14 days continuous oral treatment of SMR 500, 250 and 125 mg/kg, similar to those of resveratrol 10 mg/kg in SMR 125 mg/kg. Conclusions: The results obtained in this study propose that oral administration of SMR potently alleviates PO-induced HF by TAC, through augmentation of heart antioxidant defense system.

Development of the Control System for the Motor-Driven Electromechanical Total Artificial Hearta

  • Kim, Hee-Chan;Lee, Sang-Hun;Kim, Jong-Won-;Kim, Jin-Tae-;Min, Byoung-Goo
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1988년도 한국자동제어학술회의논문집(국제학술편); 한국전력공사연수원, 서울; 21-22 Oct. 1988
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    • pp.858-863
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    • 1988
  • A micro-processor based control system for a brushless DC motor used in the motor-driven electromechanical total artificial heart was developed. Functionally, the control system is composed of two parts. The first part is the velocity and position controller to assure that the motor follows a predetermined optimal velocity profile with minimal energy consumption, and to guarantee the full stroke length. This part also utilize the passive adaptive control method to be robust against the load disturbance, system parameter variation, and uncertainty which is the environment of artificial heart system. The pump output control is the second part, and this part provides the required responses of the artificial heart to the time-varying physiologic demands. The basic requirements of these responses are preload sensitivity, afterload insensitivity, and the balanced ventricular outputs. The performance and reliability of this control system was evaluated through a series of mock circulation tests and animal implantation, and the results are very encouraging.

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심박수 변이도를 이용한 전정자율신경반사의 분석 (Analysis of Vestibuloautonomic Reflex by Heart Rate Variability)

  • 오경아;박옥규;김민선;김재효;박병림
    • 한국감성과학회:학술대회논문집
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    • 한국감성과학회 1999년도 춘계학술발표논문집 논문집
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    • pp.243-248
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    • 1999
  • There is substantial evidence that anatomical connections and functional interactions exist between vestibular and autonomic systems. Heart rate variability (HRV) including mean, standard deviation, coefficient of variation (CV), power spectrum was analyzed for evaluation of the physiological role of the vestibular system on control of heart rate in rabbits. In anesthetized rabbits, electrical stimulation of the vagus nerve decreased heart rate and decreased LF/HF by increasing HF. On the cervical sympathetic nerve increased heart rate and increased LF/HF by increasing LF. Atropine, cholinergic blocker, increased heart rate and increased LF/HF by reducing HF, and propranolol, ${\beta}$-adrenergic blocker, decreased heart rate and decreased LF/HF by reducing LF> In unanesthetized rabbits, stimulation of the vestibular system induced by rotation or caloric increased heart rate and increased LF/HF by increasing LF> Also electrical stimulation of the vestibular nerve produced the same of effects as rotation or caloric in anesthetized rabbits. These results suggest that Stimulation of the vestibular system increased heart rate not by inhibiting the parasympathetic nerve but by activating the sympathetic nerve.

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자라에 있어서 정맥환류량(靜脈還流量)의 증가(增加)가 심박(心博)에 미치는 영향(影響) (Effects of Increasing the Venous Return on the Heart Rate in the Water Turtle - Myogenic Regulatory Mechanisms in the so-called Bainbridge Reflex -)

  • 양우진;이종은;길원식
    • The Korean Journal of Physiology
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    • 제11권2호
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    • pp.17-22
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    • 1977
  • By the intravenous infusion of saline solution through the postcaval vein, the effects of increasing the venous return on the heart rate were studied in the water turtle (Amyda japonica). The following results were obtained: 1) Prior to saline infusion, when the initial heart rate was below $50{\sim}55/min$ the heart rate was increased by the infusion. When the initial rate was above this value no changes in heart rate were observed following the infusion. 2) When the heart rate was decreased by vagal stimulation, the infusion elicited a remarkable increase in the heart rate. 3) Increased heart rate caused by tile infusion was not affected by vagotomy or sympathectomy. 4) These results suggest that the increase in heart rate secondary to increased venous return is under the control of a myogenic regulatory mechanism, not a neural mechanism.

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Cardioplegic Solution의 심근보호 효과에 관한 실험적 연구 (An Experimental Study on the Myocardial Protection Effects of the Cardioplegic Solution)

  • 이종국
    • Journal of Chest Surgery
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    • 제13권4호
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    • pp.321-337
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    • 1980
  • The increasing use of cardioplegic solution for the reduction of ischemic tissue injury requires that all cardiplegic solution be carefully assessed for any protective or damaging properties. This study describes functional, enzymatic and structural assessment of the efficiency of three cardioplegic solutions (Young & GIK, Bretschneider, and $K^{+}$ Albumin solution) in a Modified Isolated Rat Heart Model of cardiopulmonary bypass and ischemic arrest. Isolated rat heart were subjected to a 2-minute period of coronary infusion with a cold cardioplegic or a noncardioplegic solution immediately before and also at the midpoint of a 60-minute period of hypothermic ($10{\pm}1$. C) ischemic cardiac arrest. The results of this study were as follow: 1. Spontaneous heart beat after ischemic arrest occured 16 seconds later after Langendorff reperfusion in the Young & GIK group (n=6), and 40 second later in the Bretschneider group (n=6) and 6 minute later in the $K^{+}$ Albumin group (n=6), and 16 minute later in the control group (non-cardioplegia). A good recovery state of spontaneous heart beat was shown in the Young & GIK and Bretschneider groups. 2. The percentage of recorveries of heart function at 30 minute after postischemic working heart perfusion were : heart rate $91.6{\pm}3.1$% (P<0.01)m oeaj airtuc oressyre $83{\pm}3$% (P<0.01), coronary flow $70{\pm}8$% (P<0.05) and aortic flow flow rate $39{\pm}9.3$% (P<0.05) in the Young & GIK group. This percentage of recoveries of the Young & GIK group was significantly greater than the control group. In the Bretschneider group, the percentage of recoveries were : heart rate $87.8{\pm}7.5$%(P<0.05), peak aortic pressure $71{\pm}2.3$% (P<0.05) and aortic flow rate $33.2{\pm}6.6$%(P<0.05). hte percentage of recoveries were significantly greater than in the control group. In the $K^{+}$ Albumin group, recoveries of heart function were poor. 3. Total CPK leakage was $131.2{\pm}12.75$IU/30 min/gm. dry weight in the control group, $50.65{\pm}12.75$IU in the Young & GIK gruop, $69.40{\pm}32.21$Iu in Bretschneider group, and $103.65{\pm}15.47$IU in the $K^{+}$ Albumin group during the 30 minute postischemic Langendorff reperfusion. Total CPK leakage was significantly less (P<0.001) in the Young & GIK group, than in the control group. 4. Direct correlatin between percentage recovery of aortic flow rate and total amount of CPK leakage from Myocardium was noticed.(Correlation Coefficient r = 0.76, P<0.001). 5. Mild perivascular edema was the only finding of light microscopic study of myocardium after 60 minute ischemic arrest with cold cardioplegic solutions and hypothermla.

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성인 선천성 심장질환자들이 지각한 부모 양육태도, 질병인식과 불안간의 관계 (The Relationships among Perceived Parental Bonding, Illness Perception, and Anxiety in Adult Patients with Congenital Heart Diseases)

  • 신나연;장유하;강윤희
    • 대한간호학회지
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    • 제47권2호
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    • pp.178-187
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    • 2017
  • Purpose: The purposes of this study were to identify the relationships among perceived parental bonding, illness perception, and anxiety and to determine the influences of perceived parental bonding and illness perception on anxiety in adult patients with congenital heart diseases. Methods: In this study a descriptive correlational design with survey method was utilized. The participants were 143 adult patients with congenital heart disease being cared for in the cardiology out-patient clinic of A medical center. Data were collected using the Parental Bonding Instrument, Illness Perception Questionnaire Revised Scale, and Cardiac Anxiety Questionnaire Scale. Data were analyzed using descriptive statistics, independent t-test, one-way ANOVA, Pearson correlation analysis, and hierarchial regression analyses. Results: There showed significant positive relationships of anxiety with maternal overprotection, consequences, and personal control respectively. Among predictors, maternal overprotection (${\beta}=.45$), consequence (${\beta}=.26$), and personal control (${\beta}=-.03$) had statistically significant influence on anxiety. Conclusion: Nursing interventions to decrease maternal overprotection and negative consequence, and to enhance personal control are essential to decrease the anxiety of adult patients with congenital heart diseases.