• The Korean Journal of Pharmacology
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• v.30 no.3
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• pp.313-319
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• 1994

This study was undertaken to investigate the relationship between the $Na^+$ channels of the cardiovascular regulation center and the responses to increased $Na^+$ concentration in the cerebrospinal fluid (CSF), by observing the effects of icv administration of the agents affecting $Na^+$ transport. Icv infusion of $200\;{\mu}l$ of 1 M NaCl produced hypertension and bradycardia in the urethane-anesthetized rabbit, and the bradycardia was inhibited and reversed to tachycardia by vagotomy. Amiloride, a $Na^+$ transport inhibitor, produced hypertension and bradycardia, which were not altered by vagotomy, and it did not affect the NaCl-induced responses. Benzamil, a derivative of amiloride with higher specificity, neither produced any cardiovascular effects by itself, nor affected the NaCl-induced responses. In vagotomized rabbits, icv amiloride reversed the NaCl-induced tachycardia to a bradycardia, but the bradycardiac effect was not altered by pretreating with NaCl. This study showed that although amiloride and benzamil slightly differ in their cardiovascular action, neither of them did affect the NaCl-induced responses. We suggest that the $Na^+$ channels which are sensitive to amiloride or benzamil in the cardiovascular regulation center are not involved in the NaCl-induced response.

• The Korean Journal of Pharmacology
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• v.23 no.2
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• pp.77-85
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• 1987

This study was carried out to determine the role of cholinoceptors in the ventrolateral medulla on central control of blood pressure (BP) and heart rate (HR). In rats anesthetized with urethane and paralyzed, microinjections of the neuroexcitatory amino acid L-glutamate (300 ng/site) were performed to functionally identity the vasopressor area (VLPA) and the vasodepressor area (VLDA) in the ventrolateral medulla oblongata. 1. The bilateral microinjection of carbachol (300 ng/site) into the VLPA produced significantly an increase in BP and HR which was not blocked by bilateral pretreatment of hexamethoium ($4\;{\mu}g/site$). 2. The bilateral microinjection of physostigmine (200 ng/site) and oxotremorine (300 ng/site) into the VLPA produced significantly an increase in BP respectively. 3. The bilateral microinjection of atropine ($4\;{\mu}g/site$) into the VLPA produced significantly a decrease in BP and HR. 4. The bilateral micro injection of acetylcholine (500 ng/site) and dimethylphenylpiperazinium (500 ng/site) into the VLDA produced significantly a decrease in BP and HR respectively. 5. The depressor and bradycardiac responses elicited by the bilateral microinjection of acetylcholine (500 ng/site) into the VLDA were blocked by bilateral pretreatment of hexamethonium ($4\;{\mu}g/site$). The results suggest that the activation of cholinoceptors in VLPA produce hypertensive and tachycardiac responses which may be mediated by muscarinic receptors, and the activation of cholinoceptors in VLDA produce hypotensive and bradycardiac responses which may be mediated by nicotinic receptors.

• Journal of Yeungnam Medical Science
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• v.6 no.2
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• pp.241-245
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• 1989

Induction of A-V block by tachycardia is a well-known phenomenon. But there are few case reports of bradycardia-dependent A-V block. We report a case of bradycardia-dependent A-V block with review of literatures. This patient was a 52-year-old fe male who complained of dizziness and anterior chest discomfort. Electrocardiographic recording demonstrated complete A-V block. Monitor electrocardiographic recordings during sitting position and after atropine administration demonstrated decrease of degree of block from complete A-V block to first degree A-V block. The occurrence of complete A-V block for bradycardia during supine position suggests a phase 4-dependent block. After a permanent ventricular pacemaker was implanted, the patient recovered and was with out symptoms during 12 months follow up.

• Journal of Veterinary Clinics
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• v.32 no.4
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• pp.330-333
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• 2015

An 1 year old intact male mixed dog (weighing 20 kg) was presented with primary complaints of abdominal distension and severe exercise intolerance. Electrocardiogram found profound bradycardia (46-79 beats/min) with atrial standstill. Laboratory studies found no particular abnormalities. Serum cortisol and T4 concentration were within normal range. Diagnostic imaging studies revealed generalized cardiomegaly, ascites, dilation in all cardiac chambers, absence of atrial contraction, absence of transmitral A-peak, mitral and tricuspid valve insufficiency and normal left ventricular systolic dimension. Based on diagnostic findings, the case was diagnosed as idiopathic atrial standstill. The dog was treated with conventional therapy for heart failure.

• Journal of Veterinary Clinics
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• v.24 no.3
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• pp.422-425
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• 2007

A 6-month-old intact male Jindo dog was underwent surgery for hip fracture caused by hit by a car. Routine laboratory tests performed prior to surgery found no significant abnormalities, which might increase risks associated with general anesthesia. The dog was premedicated with atropine, induced general anesthesia with thiopental sodium and maintained with isoflurane. Forty minutes after surgery, the dog was suddenly bradycardic. Atropine (18 ug/kg) was slowly infused intravenously to normalize heart rate. However, paradoxically the dog showed slower heart rate with intermittent atrioventricular block ($2^{nd}$ degree type I) after atropine infusion. The dog's rhythm was returned to normal rate 7 minutes after ephedrine was infused. This is a rare case of paradoxical atrioventricular block induced by high dose of atropine in a dog.

• Clinical and Experimental Pediatrics
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• v.50 no.1
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• pp.40-46
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• 2007

Purpose : This study assessed the long term survival rate and long term complications of patients who had a modified Fontan operation for functionally univentricular cardiac anomaly. Methods : Between June 1986 and December 2000, 302 patients with a functional single ventricle underwent surgical interventions and were followed up until February 2006. The mean follow-up period was $8.3{\pm}5.3years$ (range 3.5-18 years). Their median age was 2.4 years at the Fontan operation. The survival rate, the incidence and the risk factor of late complications were evaluated retrospectively. Results : The verall survival rate was 91 percent at 5 years and 87 percent at 10 years. In multivariate analysis, early calendar year of operation and significant regurgitation were risk factors of death. The surviving patients showed NYHA functional class I in 82 percent, class II in 15 percent, and class III in 3 percent. Redo Fontan operations were necessary in 8.8 percent of patients at average $12.8{\pm}3.6years$ after initial Fontan operation. The most common cause of Fontan conversion was atrial arrhythmia. The incidence of thromboembolic events was 9.3% and these complications were associated with the occurrence of atrial tachyarrhythmia. Supraventricular tachycardia including atrial flutter or fibrillation were reported on the follow-up examination by 11.2 percent of survivors after $8.4{\pm}5.6years$. Atriopulmonary connection showed higher rates of late tachycardia than lateral tunnel operation. Conclusions : This study revealed that the recent survival rate of Fontan type operation was satisfactory, but the occurrence of late complications after a Fontan type operation increased with the longer survival. There is a need for strict follow up and early treatment of late complications in patients who had a Fontan operation.

• Journal of Veterinary Clinics
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• v.26 no.4
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• pp.344-347
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• 2009

Four sheep and five Korean native goats became intoxicated after eating Rhododendron schlippenbachii clippings that a ranchman threw into the animal barn. The clinical signs included loss of appetite, lethargy, nausea, salivation, vomiting, dyspnea, staggering gait, and bradycardia. The animals were treated with atropine and carbo-pulbit. One goat died 8 hours later, and a field postmortem revealed a considerable quantity of rhododendron leaves in the rumen. The other sheep and goats recovered within 3 days after treatment.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.3 no.3
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• pp.45-50
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• 2010

In this study, Discrete Wavelet Transform(DWT), which can detect more correct QRS complex, approximated through impulse response for reducing complexity to suit real-time system during exercise. Also, rhythm information, which is Arrythmia, Bradycardia and Tachycardia, is provided through continuously monitoring QRS complex. Proposed algorithm is evaluated by computer simulation of ECG signal that is measured during exercise.

• Journal of Veterinary Clinics
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• v.26 no.2
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• pp.166-169
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• 2009

An 11-year-old male Beagle, weighing 10.5 kg, was presented with sudden bradyarrhthmia and severe hypotension after incidental ingestion of diltiazem. The dog was treated with intravenous(IV) isotonic crystalloid solution, atropine, calcium gluconate, dobutamine, glucagon and gastric lavage under the aid of temporary transcutaneous cardiac pacing. With the short-term use of transcutaneous cardiac pacing and medical treatment, the heart rhythm and the condition of the patient were stabilized.

• The Korean Journal of Emergency Medical Services
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• v.21 no.2
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• pp.71-78
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• 2017

Purpose: The purpose of the study was to investigate the satisfaction of paramedic students with simulation-based learning in an emergency intervention for bradycardia patients. Methods: Study participants were 72 paramedic students who experienced simulation-based learning. Data on satisfaction with the intervention were collected and analyzed using SPSS 18.0. Results: The mean satisfaction score for the simulation-based learning intervention was 4.28 by Likert 5 point scale. Conclusion: Simulation-based learning can facilitate adaptation to the scene of an emergency among paramedic students.