• Transactions on Electrical and Electronic Materials
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• 제9권5호
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• pp.213-219
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• 2008

Pulse waves continuously change with respect to the characteristics and status of the cardiovascular system and in relation to the blood pressure (BP) and the pulse wave velocity (PWV). Monitoring the vascular condition by analyzing the variations in pulse waveforms has been used to diagnose vascular disorders and in drug treatment of arteriosclerosis and peripheral circulatory obstruction. In this paper, we investigated the vascular characteristic index with regard to the BP and classified by pulse wave signals. The pressure pulse wave and photoplethysmography (PPG) were measured simultaneously while subjects exercised, producing changes in the BP, to analyze the variation in the vascular characteristic index. We investigated the correlation between the BP and vascular characteristic index with regard to the classification methods of the pulse wave. The reflection index (RI) and vascular stiffness index were correlated with the diastolic BP, but no correlation was found between these parameters and the systolic BP. These results suggest the possibility of estimating BP through simple measurements of pulse waves.

• 농촌의학ㆍ지역보건
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• 제34권1호
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• pp.34-46
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• 2009

이 연구는 비교적 간단하면서도 객관성과 타당성이 높다고 평가되는 자료와 산출방식을 적용하여 보건사업의 가중치를 산출함으로써 지방자치단체 보건사업의 자원 배분과 평가에 용이하게 활용할 수 있는 계량적 기준을 제시하고자 하는 목적으로 수행되었다. 이를 위해 먼저 HP 2010에서 제시한 중점과제를 기초로 선행연구의 결과와 보건복지부 사업담당자들의 의견을 반영하여 분류안을 구성하였다. 다음으로 선행연구 결과들을 검토하여 각 보건사업과 관련된 질병부담 자료를 수집하였고, 전문가 의견 조사를 실시하여 각 보건사업과 관련된 문제의 심각도와 사업의 추정 효과를 파악하였다. 그리고 이와 같은 과정을 통해 수집된 자료들을 BPRS 방식에 적용하여 보건사업의 가중치를 산출하였다. 수집된 자료들을 BPRS 공식에 대입하여 가중치를 산출한 결과 전염성질환이 58.97%로 가장 높았고, 금연이 14.07%로 두 번째로 높았다. 그 다음은 고혈압(3.87%), 당뇨(3.40%), 암(2.90%), 심 뇌혈관질환(2.86%), 운동(2.10%), 절주(2.07%), 건강검진(1.92%), 정신건강증진(1.72%), 중증정신질환(1.62%), 영양(1.52%), 구강위생관리(1.15%), 구강질환(1.10%), 중독(0.73%) 순으로 나타났다. 이 연구의 결과는 중앙정부가 지방자치단체 보건사업에 자원을 배분할 때 계량적 기준으로 활용할 수 있으며, 평가점수 산정 시 상대적으로 더 중요한 사업에 더 높은 점수를 부여하여 사업의 효과성을 정책적으로 향상시킬 수 있을 것으로 기대된다.

• 한국임상약학회지
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• 제28권4호
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• pp.293-299
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• 2018

Background: 3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) effectively reduce serum levels of low-density lipoprotein (LDL) and total cholesterol. High-intensity statins are recommended for all patients aged ${\leq}75$ with clinical atherosclerotic cardiovascular disease (ASCVD), diabetes mellitus aged 40-75 with ${\geq}7.5%$ estimated 10-year ASCVD risk and LDL-C ${\geq}190mg/dL$. High-intensity statins associated with more frequent adverse events (AEs) compared to moderate- to low-intensity statins. The aim of this study was to compare AEs between high-intensity and moderate- to low-intensity statin group using the Korea Adverse Event Reporting System (KAERS) database. Methods: Adults (${\geq}18years$) with statin-associated AEs from July 2009-June 2014 were included. Only AEs classified as "certain", "probable" and "possible" based on the WHO-Uppsala Monitoring Center criteria were analyzed. Results: In total, 247 AEs from 196 patients [high-intensity statin group (HG), n = 25 (13%); moderate- to low-intensity statin group (MLG), n = 171 (87%)] were included. Mean age was higher in HG compared with MLG ($67{\pm}14$ vs $62{\pm}12$). The HG showed a significant higher frequency of liver/biliary system disorders (37% vs 14%, p = 0.001). Hepatic function abnormal was reported more frequently in HG compared to MLG (26% vs 9%, p = 0.006). Conclusion: According to KAERS data, liver/biliary system disorders were more frequently reported in HG compared to MLG.

• 전자공학회논문지CI
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• 제46권6호
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• pp.18-26
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• 2009

본 논문에서는 심전도 기반의 u헬스케어시스템을 위한 다용도 신호추출 방법을 제안한다. 심전도 기반의 u헬스케어시스템 구현을 위해서는 심장질환 진단을 위한 QRS파형의 추출기술이 필수적이다. 또한, 보안성 및 편의성을 위하여 u헬스케어시스템에서 ECG신호와 같은 생체신호에서 직접 사용자의 신원을 확인할 수 있는 생체인식기능을 보유하고 있다면 매우 유용하다. 이를 위해서 본 논문에서는, 리드II 파형으로부터 QRS파형을 추출하고, 또한 상대적으로 노화 및 질환에 따른 변동에 강건한 리드III 파형으로부터 생체인식을 위한 신호추출법을 제안한다. 리드II 파형으로부터 QRS신호추출성능을 검증하기 위해 MIT-BIH 데이터베이스의 심전도신호가 사용되었고 99.36%의 정확도 및 99.68%의 민감도성능을 보였다. 또한 생체인식용 신호추출성능평가를 위해서는 다양한 측정환경을 고려하기 위해 음주, 흡연 및 운동 직후 리드III파형이 측정되었고 99.92%의 정확도 및 99.97%의 민감도 성능을 보였다.

• 센서학회지
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• 제17권2호
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• pp.87-94
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• 2008

Blood pressure (BP), one of the most important vital signs, is used to identify an emergency state and reflects the blood flow characteristics of the cardiovascular system. The conventional noninvasive method of measuring BP is inconvenient because patients must wear a cuff on their arm and the measurement process takes time. This paper proposes an algorithm for estimating the BP using the pulse transit time (PTT) of the photoplethysmography (PPG) and pressure pulse from finger at the same time as a more convenient way to measure the BP. After recording the electrocardiogram (ECG), measuring the pressure pulse, and performing PPG, we calculated the PTT from the acquired signals. Then, we used a multiple regression analysis to measure the systolic and diastolic BP indirectly. Comparing the BP measured indirectly using the proposed algorithm and the real BP measured with a sphygmomanometer, the systolic pressure had a mean error of ${\pm}3.240$ mmHg and a standard deviation of 2.530 mmHg, while the diastolic pressure had a satisfactory result, i.e., a mean error of ${\pm}1.807$ mmHg and a standard deviation of 1.396 mmHg. These results are more superior than existing method estimating blood pressure using the one PTT and satisfy the ANSI/AAMI regulations for certifying a sphygmomanometer i.e., the measurement error should be within a mean error of ${\pm}5$ mmHg and a standard deviation of 8 mmHg. These results suggest the possibility of applying our method to a portable, long-term BP monitoring system.

• 약학회지
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• 제50권2호
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• pp.129-135
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• 2006

Two Antihistamines, terfenadine and astemizole have been withdrawn from major markets for the reason that these durgs have been reported to induce QT interval prolongation associated with the onset of Torsades do Pointes (TdP), resulting in a life-threatening ventricular arrhythmia. In this study, we investigated effects of diphenhydramine on electrocardiograms and hemodynamic parameters in conscious telemetered dogs. We validated and defined the sensitivity of the test system by monitoring basal parameters and using positive control substance, terfenadine. Single administration effects were tested during 24 hours for each test drug at dose 1 mg/kg, 10 mg/kg, 30 mg/kg, 100 mg/kg. We monitored QT, QTc, heart rate, blood pressure and body temperature after administering test drugs. In conscious telemetered dogs, diphenhydramine significantly prolonged $QT\;(6.8\%\;of\;basal)\;and\;QTc\;(7.8\%\;of\;basal)$ at 100 mg/kg. Other parameters were not affected significantly. These findings suggest that antihistamines could induce important clinical relevance for patients taking excessive dosages of conventional antihistamines and those at risk of developing cardiac arrhythmias. Future studies that include other antihistamines and other classes will be necessary to predict the torsadogenic risk of drugs in humans.

• 대한원격탐사학회지
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• 제38권6_1호
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• pp.1191-1205
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• 2022

복잡하고 광범위한 원인을 가진 대기오염물질 중 particulate matter (PM)은 입자의 크기에 따라 분류된다. 그 중 PM_2.5는 그 크기가 매우 작아 사람이 흡입하면 인간의 호흡기나 심혈관에 질병을 유발할 수 있다. 이러한 위험에 대비하기 위해서는 국가 중심의 관리와 사전에 예방할 수 있는 모니터링 및 예측이 중요하다. 본 연구는 고농도 미세먼지의 발생이 잦은 서울시의 PM_2.5를 local data assimilation and prediction system (LDAPS) 기상 관련 인자 15가지와 aerosol optical depth (AOD), 화학인자 4가지를 독립변수로 하여 앙상블 모델 두 가지 random forest (RF)와 extreme gradient boosting (XGB)로 예측하고자 하였다. 예측에 사용된 두 모델의 성능 평가와 인자 중요도 평가를 수행하였으며, 계절별 모델 분석도 수행하였다. 예측 정확도 결과, RF가 R² = 0.85, XGB가 R² = 0.91의 높은 예측 정확도를 보이며 XGB가 RF보다 PM_2.5 예측에 적합한 모델임을 확인하였다. 계절별 모델 분석 결과, 봄에 농도가 높은 관측 값과 비교하여 예측 수행이 잘 되었다고 할 수 있다. 본 연구는 다양한 인자를 이용하여 서울시의 PM_2.5를 예측하였고, 좋은 성능을 보이는 앙상블 기반의 PM_2.5 예측 모델을 구축하였다.

• Clinical and Experimental Pediatrics
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• 제58권12호
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• pp.484-490
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• 2015

Purpose: To determine the efficacy and safety of oral propranolol as a first-line treatment for superficially located infantile hemangioma (IH) and propose an assessment tool to measure treatment response. Methods: Patients with superficial IH under 1 year of age were prospectively recruited between May 2012 and December 2013 at the Department of Pediatrics of Chungbuk National University Hospital. Propranolol was administered to 12 infants (median age, 3.8 months) while monitoring cardiovascular and adverse metabolic effects. If a patient showed no adverse events, the dosage was gradually increased up to 3 mg/kg/day and maintained for 1 year. We used our own scoring system to assess treatment response using parameters like change in color, and longest diameter, and thickness of the IH. Results: Eleven out of 12 patients completed the protocol with consistent improvement of hemangiomas during therapy. Patients on propranolol showed a more than 50% involution in the first 3 months, with additional steady involution until 1 year. Patients with the highest scores at 1 month maintained their score and showed better responses until treatment termination. The patient with the lowest score at 1 month did not show any further regression and stopped propranolol treatment 4 months after initiation. In two children with recurrences after successful therapeutic regression, propranolol was effective after being reintroduced. Propranolol treatment was not interrupted in any patient due to adverse events. Conclusion: Oral propranolol at 3 mg/kg/day showed a consistent, rapid, and therapeutic effect on superficial IHs without significant adverse events.

• Journal of Chest Surgery
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• 제32권10호
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• pp.903-909
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• 1999

Background: The current study was undertaken to investigate the results of a modification in the conventional Maze III Procedure devised by the authors. The aim of the technical modification was in improving the left atrial contractility. Material and Method: Between July 1997 and December 1998, 34 patients with chronic atrial fibrillation for more than 1 year duration underwent a modified Maze III procedure. The assessment of the left atrial function was made by various echocardiographic measurements and SA nodal recovery was evaluated by HRV Holter monitoring. Result: All 34 patients were in sinus rhythm. On echocardiography, right atrial contraction was detected in 32 patients(94.1%) and left atrial contraction in 33 patients(97.1%). The echocardiographic A wave at 1, 6, and 12 months or more were 50.5$\pm$31.5, 62.1$\pm$25.1, 66$\pm$20.6 cm/sec, respectively, and the E wave measurements at the same time points were 152$\pm$31.1, 134.4$\pm$35.2, 133$\pm$27.5 cm/sec. The corresponding A/E ratios were 0.32$\pm$0.13, 0.48$\pm$0.18, 0.5$\pm$0.15, showing a rising trend. Treadmill evaluation at 6 months showed a mean 82% increase in heart rate after excising, and the SDNN and SDANN upon HRV Holter at 1 and 3 months postoperatively were 65.3$\pm$28.1/87.8$\pm$27.2 ms, and 60.0$\pm$24.1/83.4$\pm$25.7 ms, respectively, showing a predoinant autonomic recovery in the parasympathetic system(PSDNN = 0.01, PSDANN =0.015). Conclusion: The results of our data suggest that the current modification in the conventional Maze III Procedure was efective in enhancing the postoperative left atrial contractility.

• Journal of Ginseng Research
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• 제34권1호
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• pp.8-16
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• 2010

Attention deficit hyperactivity disorder (ADHD) affects 4-12% of chool-age children worldwide and is characterized by three core symptoms: hyperactivity, inattention, and impulsivity. Although standard pharmacological treatments, such as methylphenidate and atomoxetine, are available, concerns about drug-induced psychological and cardiovascular problems, as well as growth retardation and sleep disturbances, highlight the continuing need for new therapeutic interventions. Using a neonatal hypoxia-induced hyperactivity model in rats, the potential positive role that oral administration of red ginseng extract may have in relation to the hyperactive phenotype was investigated. Hypoxia was induced in 2-day-old male Sprague-Dawley (SD) rat pups by placing them in a nitrogen chamber for 15 min. The neonatal hypoxia-induced rats showed a significant increase in hyperactivity phenotype, such as increased movement duration, movement distance, and rearing frequency, which was determined by monitoring their spontaneous locomotor activity using the Ethovision video tracking system. One week of oral treatment with red ginseng extract decreased the hyperactivity phenotype of the neonatal hypoxia-induced rats and increased the locomotor activity of the control rats. In the neonatal hypoxia-induced rats, expression of the norepinephrine transporter in the forebrain was increased, and red ginseng treatment partially prevented its up-regulation, while increasing its level in the control rats. Taken together, these results suggest that red ginseng extract decreased the neonatal hypoxia-induced hyperactivity phenotype, although it increased locomotor activity in normal animals.