• 약학회지
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• 제32권6호
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• pp.402-414
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• 1988

In order to clarify the receptor types and mechanisms underlying the positive inotropic effect of dopamine on the mammalian ventricular myocardium, the action potential, its first derivatives and isometric contraction of the rabbit papillary muscle were recorded using a force transducer and glass capillary microelectrodes filled with 3M KCl. The results were as follows; (1) In normal Tyrode solution, the contractile force was increased and duration of action potential was shortened with increments of dopamine concentration ($10^{-6}-10^{-4}M$). (2) The dose-response curve was markedly shifted to the right by pretreatment with reserpine (5mg/kg i.p., 24hrs prior to the experiment). (3) In 19mM $K^+-Tyrode$ solution, the duration of action potential, maximum rate of rise (V_{max}) of action potential and overshoot were significantly increased with increments of dopamine concentration ($10^{-6}-10^{-4}M$). (4) The inotropic effect of dopamine on the rabbit papillary muscle pretreated with reserpine was antagonized by atenolol ($10^{-6}M$), but not by phentolamine ($3{\times}10^{-6}M$). (5) In rabbit papillary muscle partially depolarized by 19mM $K^+-Tyrode$ solution, slow electrical response (calcium mediated action potential) as well as contraction were restored by dopamine ($10^{-4}M$); this restoration was blocked by calcium antagonists ($3{\times}10^{-5}M$ $LaCl_3{\cdot}6H_2O$, $3{\times}10^{-6}M$ diltiazem) or ${\beta}-adrenoceptor$ antagonist ($3{\times}10^{-6}M$ atenolol), but not affected by ${\alpha}-adrenoceptor$ antagonist ($10^{-5}M$ phentolamine, $3{\times}10^{-6}M$ yohimbine) or vascular dopaminergic receptor antagonist ($10^{-5}M$ haloperidol). The above results may be interpreted as that the positive inotropic effect of dopamine through both direct and indirect action are caused by increase in slow inward current ($Ca^{2+}$ influx into themyocardial cell), and the direct action is mainly due to the stimulation of ${\beta}-adrenoceptors$ in the rabbit papillary muscle.

• 대한수의학회지
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• 제41권3호
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• pp.311-317
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• 2001

In this work we have investigated the physiological effects of $MgCl_2$ in isolated atrium, papillary muscle, perfused heart and anesthesized guinea pig, The addition or infusion of $MgCl_2$ (0~20 mM or mg/kg) to perfused hearts and to anesthesized guinea pigs induced a marked and dose-dependent negative chronotropic effect. The sinoatrial node automaticity could also be reduced by $MgCl_2$. The addition of $MgCl_2$to isolated atria and to papillary muscles induced a marked and dose-dependent negative inotropic effect. The threshold voltage could be increased by $MgCl_2$in papillary muscle. Increasing $MgCl_2$ shortened the action potential duration (APD) in dose-dependent manner at 30% ($APD_{30}$) and 90% repolarization ($APD_{90}$) measured with conventional microelectrode technique in papillary muscle. In anesthesized guinea pig, the magnesium infusion resulted in a dose-dependent drop in blood pressure. These results suggested that magnesium is closely associated with cardiac physiological condition and exerts antiarrhythmic activities.

• 대한두경부종양학회지
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• 제30권2호
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• pp.115-118
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• 2014

Papillary thyroid carcinoma is known as its relatively high cure rate after surgical treatment. But invasion of the trachea by thyroid carcinoma is poor prognostic factor and the best management is en bloc surgical resection of the tumor invading the trachea. A 55-year-old man was diagnosed as papillary thyroid cancer with tracheal invasion. We treated the patient by total thyroidectomy with window resection of invading trachea followed by immediate reconstruction with sternohyoid muscle flap and tracheostomy. At 48 days after surgery, tracheostoma was closed and the patient had no functional complication by the surgical process. Until 10 months after surgery, there was no sign of recurrence and the patient led social life without any discomfort. We present this case with a review of the related literatures.

• Journal of Chest Surgery
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• 제16권1호
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• pp.34-39
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• 1983

The syndrome of anomalous muscle bundle dividing the right ventricle into two pressure chambers has been described by many authors. The malformation should not be confused with tetralogy of Fallot itself because the obstructive hypertrophic bands are usually proximal to the right ventricular infundibulum. One case [11 years old male] of double chambered right ventricle due to aberrant muscle bundle with intact ventricular septum is presented. The pressure gradient was 68 mmHg between inflow and outflow tracts of right ventricle on cardiac catheterization. On opening the right ventricle, there noted stenosis of outflow tract by infundibular membrane, hypertrophied anomalous muscle bundle, thickened moderator band & hypertrophied anterior papillary muscle. Open heart surgery was carried out with the aid of extracorporeal support, Anomalous muscle bundle [1.0 cm x 4.0 cm] and infundibular membrane were resected safely. The hypertrophied moderator band was cut at mid-portion and anterior papillary muscle was split vertically. The postoperative course was uneventful and discharged in good condition 2 weeks later.

• 대한약리학회지
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• 제12권1호
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• pp.45-55
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• 1976

The effect of positive inotropic agents on the contractile properties of myocardial muscle were studied in the cat papillary muscle preparation. For the purpose, the effects of ouabain $(1{\times}10^{-6}g/ml)$, norepinephrine (0.05r/m1) and Aconiti tuber butanol fraction (AF(5), $1{\times}10^{-4}$, $5{\times}10^{-4}$, $1{\times}10^{-3}$, $2{\times}10^{-3}g/ml$) on the contractile dynamics of the papillary muscle preparation isolated from right ventricle of cat were observed in terms of the characteristics of isometric twitch and the lengh-tension relation, the force-velocity relation and the load-extension relation of the series elastic component of contractile model of A.V. Hill. All the studied inotropic drugs similary increased the rate and the intensity of the developed isometric tension, while shortened the time from onset of contraction to peak tension and the total duration of contraction. In the afterloaded simultaneous isotonic and isometric contraction, they also similary increased the maximal velocity of shortening accompanied with the increasing the maximum developed force. In the load-extension relation all the drugs, however, had no appreciable influence on the properties of the series elastic component. Increasing the concentration, Aconiti tuber butanol fraction produced more pronounced effect on all the studied parameters of isometric and isotonic contraction of cat papillary muscle preparation. From the aspect of contractile dynamics, it seemed that the positive inotropic effect of ouabain, norepinephrine and Aconiti tuber butanol fraction are similary achieved through an influence on the behavior of the contractile component only.

• The Korean Journal of Physiology
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• 제22권2호
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• pp.207-218
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• 1988

Effects of 1, 4-dihydropyridine compounds, such as nifedipine, nisoldipine, nitrendipine, and nimodipine which were calcium antagonists on the normal and Ca-dependent, slow channel mediated action potentials in the guinea pig's papillary muscle were investigated. The glass microelectrode was impaled into a papillary muscle cell for measurements of potential changes with the simultaneous tracing of isometric contraction. The concentration of Ca antagonists were 1 mg/l (nifedipine and nisoldipine), 2 mg/l (nitrendipine and nimodipine), which showed the maximal inhibition of isometric contraction (above 90%) and simultaneous effects on the normal action potentials and only the halves of those concentrations were sufficient to observe the effects on the calcium action potentials. The data for analysis were only chosen when the microelectrode was maintained in a cell throughout the experiments. 1, 4-Dihydropyridine compounds decreased the action potential duration but did not affect the resting membrane potential, overshoot, and upstroke velocity of the normal action potentials with the decrease in the isometric contraction. And with the decrease in the area and amplitude of isometric contraction, the area, amplitude, upstroke velocity and duration of Ca action potential was decreased. But the differences in the effects of the Ca antagonists were not observed. Therefore it is inferred that the changes in normal and Ca action potential induced by the 1, 4-dihydropyridine compounds with a common chemical structure would be caused by the slow inward Ca-current, not by a fast Na-current.

• Journal of Chest Surgery
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• 제39권7호
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• pp.549-552
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• 2006

심각한 허혈성 심근병증(ischernic cardiomyopathy, ICMP)에 동반된 승모판 폐쇄부전증에 있어서 심장이식이 여의치 않은 상황에서의 수술적 치료로는 경색이 아닌 부위의 심근(viable myocardium)에 대한 관상동맥 우회술(coronary revascularization)과 좌심실 용적 축소술(LV reduction), 승모판 재건술(mitral reconstruction)이 그 중심으로 자리잡고 있다. 허혈성 심근병증에 있어서 승모판 폐쇄 부전은 다양한 병인으로 나타나며, 그 중 판막륜의확장 외에도 유두근의 전위가 중요한 원인으로 지적되고 있다. 본원에서는 승모판 폐쇄 부전증을 동반한 좌 주 관상동맥을 포함한 심한 관상동맥질환과 허혈성 심근병증 환자에 대한 관상동맥 우회술과 함께, 좌심실 절개를 통한 승모판 뒤판엽 성형술(posterior mitral annuloplasty), 유두근 단축술(Papillary muscle plication)의 수술적 치험을 보고하고자 한다.

• Journal of Chest Surgery
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• 제45권6호
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• pp.401-403
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• 2012

A 29-year-old man was admitted for abrupt dyspnea and hemoptysis. An echocardiogram revealed severe mitral regurgitation due to papillary muscle rupture for which an emergency mitral valve replacement operation was performed 4 days after admission. Herein, we report our experience with this case along with a review of the literature.

• 대한기관식도과학회지
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• 제12권2호
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• pp.31-34
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• 2006

Simultaneous occurrence of medullary and papillary thyroid carcinomas in the same gland is very rare. In fact. there are only 18 cases of simultaneous occurrence of medullary and papillary thyroid carcinomas in the literature. We report a case of simultaneous medullary and papillary carcinoma of thyroid gland. A 67-year-old woman was diagnosed with medullary carcinoma of right lobe of thyroid gland and papillary carcinoma of left lobe of thyroid gland by fine needle aspiration cytology. Total thyroidectomy, anterior neck dissection, bilateral modified radical neck dissection and tracheotomy was undertaken. The tumor metastasized to regional lymph node and extrathyroidal muscle invasion of left papillary carcinoma was also revealed by pathological report. This report describes a case of thyroid carcinoma that demonstrated both medullary carcinoma and papillary components in the thyroid with lymph node metastasis.

• 한국가시화정보학회지
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• 제16권2호
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• pp.31-37
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• 2018

Ischemic mitral regurgitation (IMR) is the primary mitral valve (MV) pathology in the aftermath of myocardial infarction as a consequence of regional left ventricular (LV) remodeling. We investigated the effect of asymmetric papillary muscle (PM) displacement and annular dilation on IMR development. Virtual MV modeling was performed to create a normal human MV. Asymmetric PM displacement, asymmetric annular dilation, and the combination of these two pathologic characteristics were modeled. Dynamic finite element evaluation of MV function was performed across the complete cardiac cycle for the normal and three different IMR MV models. While the normal MV demonstrated complete leaflet coaptation, each pathologic MV model clearly revealed deteriorated leaflet coaptation and abnormal stress distributions. The pathologic MV model having both asymmetric PM displacement and annular dilation showed the worst leaflet malcoaptation. Simulation-based biomechanical evaluation of post-ischemic LV remodeling provides an excellent tool to better understand the pathophysiologic mechanism of IMR development.