• 약학회지
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• 제45권3호
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• pp.276-281
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• 2001

The present study was conducted to evaluate the effect of KST221085, a newly synthesized antidiabetic agent, on the hearts from streptozotocin (STZ)-induced diabetic rats. In isolated diabetic hearts, left ventricular developed pressure (LVDP), heart rate (HR) and coronary flow rate (CFR) were decreased compared to normal control, indicating cardiovascular dysfunction in diabetic heart. The treatment with 10 $\mu$M KST221085 remarkably improved the diabetes-induced contractile impairment, without any influence on HR. Reduced coronary flow in diabetic heart was also significantly increased by treatment with 10 $\mu$M KST221085. In isolated aorta from diabetic rat, treatment with 10 $\mu$M KST221085 increased endothelium-dependent relaxation, suggesting that KST221085 can improve the impaired endothelial function in diabetic aorta. Our results suggest that KST221085 treatment can improve the cardiovascular dysfunction in STZ-induced diabetic rats.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 추계학술대회
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• pp.451-454
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• 1997

It has been reported that sudden cardiac death and ventricular tachycardia occur after treatment of tetralogy of fallot(TOF). It is regarded that ventricular arrythmia is the main source or the sudden cardiac death, but it is not verified. It is likely that TOF has effect on the heart rate variability because of the ventricular arrythmia. We study how complex and periodic heart rate dynamics change in the normal children (n=13) and TOF children (n=13) throughout 24 hours. We recorded 24-hour holter ECG, and segmented each ECG data into 1 hour length. We analyze each HR time series, and quantify the overall complexity of each HR time series by its correlation dimension. We also calculate the power spectrum of HR, and obtain low-frequency component (0.03-0.15Hz) and high-frequency component (0.15-0.4Hz). We compare the results between normal and TOF groups throughout 24 hours. TOF group have lower correlation dimension ($4.055{\pm}0.4134$ vs. $4.9310{\pm}0.2054$, p<0.05) than the normal group, even though there are no significant differences in the low($0.9864{\pm}0.5598$ vs. $1.5560{\pm}0.8325$, p<0.05) and high($1.1168{\pm}0.1.1448$ vs. $0.9271{\pm}0.6528$, p<0.05) frequency components. It can be concluded that HR time series of TOF group are more regular than that of normal group, and that correlation dimension reveals a nonlinear characteristics of HR time series which is not determined in the frequency domain.

• 국제물리치료학회지
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• 제8권1호
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• pp.1114-1121
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• 2017

The purpose of this study was to investigate the effects of hypobarichypoxic training program on competitive performance. This was done by observing their conditioning and measuring their blood constituents before and after a multi-staged intermittent training program, over 2 weeks. Three national handicapped cyclists were placed in a multi-leveled hypobaric-hypoxic (flat-4000 meter (m) high elevation) environment with consistent temperature and humidity ($23{\pm}2^{\circ}C$, $50{\pm}5%$) for 2 weeks. After the training, the blood constituents and average heart rate (HR) were measured and the following results were obtained. In all three athletes, there were no unique changes in red blood cell count, hemoglobin, and hematocrit, while there was a rise in the reticulocyte count. Observations of the difference in average HR during exercise at varying altitudes showed that athlete A had an average increase in the HR for the first 5 days at 2000 m. For athlete B, the comparison of the first and last training sessions at an altitude of 2000 m showed an HR increase of approximately 17%. For athlete C, there was a steady increase in the HR until day 7 of the training. As such, hypobaric-hypoxic training suggested that improvement of aerobic exercise performance in these athletes and it is recommended that there be a development for future training programs at high altitude, geared towards handicapped athletes of various disciplines.

• 한국임상약학회지
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• 제7권1호
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• pp.33-39
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• 1997

Cardiac and antihypertensive effects of BMS-180448, a cardiac-selective ATP-sensitive potassium channel opener, and its newly synthesized derivatives KR-31281, KR-31282 and KR-31299 were evaluated in isolated perfused rat hearts (25 min global ischemia/30 min reperfusion) and conscious rats. Three new compounds $(10\;{\mu}M)$ induced positive inotropism as evidenced by increased LVDP (left ventricular developed pressure) and RPP (Rate-Pressure Product) in nonischemic rat heart. HR-31299 increased CF (coronary flow) and HR (heart rate) but the other two had no effects. KR-31282, KR-31281 and HR-31299 had a tendency to increase reperfusion LVDP and RPP compared with vehicle, while the latter two significantly reduced reperfusion EDP with a tendency to inclose TTC (time to contracture). All three KR-compounds had very weak effects on MBP and HR in conscious rats. These results indicate that KR-31281 and HR-31299 may have some cardioprotective effects, although weaker than BMS-180448, and their mode of action different from that of BMS-180448, despite the similarity in major structural moeity.

• The Korean Journal of Physiology and Pharmacology
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• 제3권2호
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• pp.231-236
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• 1999

This study was performed to examine 1) Whether hypothermic cardiac arrest produces myocardial HSP72 expression; 2) And if, whether it serves to protect the heart against the subsequent hypothermic arrest. In the present study, neonatal rats were placed in an icebath to induce hypothermia. To determine whether hypothermic cardiac arrest produces myocardial HSP72, experimental animals were subjected to 10-min hypothermic insult before the extraction of the heart. The intervals between the insult and extraction were 1 (1 HR), 4 (4 HR), 8 (8 HR), 24 (24 HR) or 72 (72HR) hours. A minimal amount of HSP72 was detected in control, 1 HR and 72 HR groups. In contrast, 8 HR and 24 HR groups showed a significant level of HSP72 expressions. To assess the cardioprotective effect of HSP72 against hypothermic cardiac arrest, we compared the proportion of recovery from the arrest between control and preconditioned (PREC) animals. Control animals were subjected to 20-min hypothermic insult, while PREC group was preconditioned by 10-min hypothermic insult 8 hours before the 20-min test hypothermic insult. Resuscitation rate from cardiac arrest induced by the 20-min hypothermic insult in PREC group was significantly higher than that in controls. These results suggest that the cardioprotective effect of hypothermic preconditioning is associated with an increase in HSP72 expression.

• 한국산학기술학회논문지
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• 제14권12호
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• pp.6373-6386
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• 2013

본 연구는 MBTI 성격유형과 심박변이도의 관계를 조사하기 위해 시도된 연구이다. 충청남도 C 시에 소재 한 N대학교 일개 응급구조학과 재학생들을 대상으로 학교 내에서 안정상태로 측정한 심박변이도와 병원 임상실습 중 2주째와 4주째에 측정한 심박변이도를 비교분석하였다. 자료수집기간은 2013년 6월 21일부터 7월 23일까지였으며, MBTI 성격유형에 따른 안정 및 실습기간의 심박변이도의 변화에서 네 가지 성격유형별 분포도에 따른 안정 및 실습기간의 HRV에서는 nHF와 SDNN에서 유의한 차를 보였다. 전체 지표별 선호 분포도에 따른 안정 및 실습기간의 심박변이도의 변화에서 nLF는 T-F, J-P 그룹, nHF에서는 T-F, J-P 그룹, SDNN에서는 S-N, mHR에서는 J-P 그룹에서 유의한 차이가 있었다.

• The Journal of Korean Physical Therapy
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• 제30권5호
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• pp.181-186
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• 2018

Purpose: This study investigated the effects of home-based exercise intensity on the aerobic capacity and 1 year re-hospitalization rate in patients with chronic heart failure (CHF). Methods: Forty seven patients with CHF (males 33, females 14, age $61.3{\pm}9.8years$) participated in this study. The patients were allocated randomly to 3 groups in accordance with home-based exercise intensity: no home based exercise (NHE, 40%, n=19), moderate intensity home-based exercise (MIHE, 43%, n=20), and high intensity home based exercise (HIHE, 17%, n=8). All patients completed the symptom-limited cardiopulmonary exercise (CPX) test safely at the cardiac rehabilitation hospital. Results: The NHE group significantly showed lower peak $VO_2$ and a higher $VE/VCO_2$ slope than the MIHE (p<0.05) and HIHE (p<0.01) groups. On the other hand, the NHE group did not show significant differences in the other hemodynamic responses, such as heart rate (HR) max, HR reserve, maximal systolic blood pressure (SBP), and SBP reserve. Nine out of 19 NHE patients (47%) were re-hospitalized related to heart disease and two out of 20 MIHE (10%) patients were re-hospitalized, but nobody in the HIHE group were re-hospitalized within 1 year from the CPX test. Conclusion: In patients with CHF, home-based self-exercise is one of the important factors for reducing the re-hospitalization rate. In addition, improved aerobic capacity is strongly associated with a lower re-hospitalization rate. In particular, re-hospitalized CHF patients showed significant differences in respiratory parameters and hemodynamic parameters compared to the non-re-hospitalized patients.

• The Korean Journal of Physiology
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• 제8권2호
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• pp.79-90
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• 1974

In 24 men and 12 women recovery of heart rate after strenuous exercise was observed before and after administration of total ginseng glycosides. In men 100 mg of ginseng glycosides were given twice with a 3 hour interval on the day of treadmill test and in women two more administrations of ginseng glycosides were added on the day before the exercise test. The action of ginseng glycosides was interpreted as an adaptogen, i.e., to enhance the recovery to the physiological equilibrium from the displace4 state. Recovery of heart rate to the pre-exercise state was observed for 20 minutes after strenuous exercise of 2 minutes duration on a treadmill (8 km/hr, 15% grade). In men the recovery of heart rate was enhanced$(P<.2{\sim}.4)$ after ginseng glycosides administration. In women the acceleration of recovery heart rate was highly significant $(P<.01{\sim}.05)$ after ginseng glycosides administration. In men and women recovery heart rate at 3 minute of recovery period after ginseng glycosides equaled to the value at 6 minute of recovery period before ginseng administration.

• Asian-Australasian Journal of Animal Sciences
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• 제13권7호
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• pp.1003-1009
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• 2000

Four young swamp buffalo cows of similar age ranging in body weight (W) between 280 to 380 kg and trained for doing physical exercise were used in two consecutive experiments, each using a latin square design, to determine energy expenditure for draught. The experiments consisted of field trials using 4 levels of work load, i.e. no work as control and loads amounting 450 to 500 Newton (N) continuous traction for respectively 1, 2 and 3 h daily for 14 consecutive days for experiment 1, and no work, traction loads equaling 5, 10 and 15% of W for 3 h daily for 14 days for experiment 2. Heart rate during rest and exercise was monitored using PE-3000 HR monitor. Cows were fed only king grass (Penisetum purpuroides) ad libitum and were subjected to balance trials. Body composition was estimated in vivo by the body density method and daily energy expenditure (EE) was calculated from ME minus RE. RE was calculated from the changes in body-protein and -fat measured before and immediately after the 14 d experimental period assuming an energy equivalent of 39.32 MJ/kg fat and 20.07 MJ/kg protein. $E_{exercise}$ ($EE_{work}\;-\;EE_{resting}$), which was the energy spent for doing the traction during 1, 2 and 3 h was 7.13, 15.45 and 19.90 MJ, respectively. $EE_{work}$ for the 1 h treatment group was 39.75 MJ/d equivalent to 1.30 times $EE_{resting}$. The values for the 2 and 3 h treatment groups were 1.75 and 1.86 times resting energy requirement, respectively. Absolute efficiency of work in all exercise trials of experiment 2 was around 27.28%. The increases of daily $E_{exercise}$ values were correlated to elevation of heart rate (HR) according to the equation $E_{exercise}=(0.270HR^{0.363}\;-\;1)$ MJ, while draught force related to heart rate according to the equation DF (N)=6.66 HR - 361.62. Blood glucose and triglyceride levels were gradually elevated with time during the course of exercise. Mean values of blood glucose were 91.7, 115.0 and 116.2 mg/dl for cows after 1, 2 and 3 h pulling loads at 15% W respectively as compared to 88.2 mg/dl prior to work. In the same order and treatment, mean blood triglyceride concentrations were 13.5, 13.3 and 14.8 mg/dl, and 11.5 mg/dl for control. For blood lactate, the values were 1.68, 1.63 and 1.66 mM, and 0.80 mM for control. Glucose was used as the major source of energy during the initial phase of exercise, but for prolonged work, fat will replace carbohydrate as the main substrate. Accumulation of lactate persisted for some time at the end of the exercise trials.

• 감성과학
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• 제7권3호
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• pp.27-35
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• 2004

본 연구는 피부전도도(skin conductance response), 말초혈관 반응(peripheral plethysmograph), 피부온도 (skin temperature)와 심박수(heart rate)와 같은 다양한 생리신호를 측정하여 운전자의 심리반응을 통하여 적정 운전상태를 분석하고자 하였다. 운전자의 심리반응을 측정 및 분석하기 위하여 하드웨어와 알고리듬을 개발하였으며, 운전상황은 자동차 시뮬레이터를 이용하여 다양한 가상 운전상황을 설정하고 생리신호를 측정하였다. 측정 결과 운전자 생리신호가 운전환경의 변화에 따른 심리적 긴장 또는 이완 수준을 잘 반영하고 있고, 감정적 변화에는 다소 둔감한 것으로 나타났다. 이를 심리적 순위척도를 이용하여 정량화하여 심리적 적정 운전범위를 제안하였다. 본 연구의 결과는 추후 운전자의 안전운전이나 건강상태를 모니터링 하기 위한 시스템 개발의 자료로 활용할 수 있을 것이다.