• Journal of IKEEE
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• v.28 no.2
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• pp.221-227
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• 2024

This paper presents a smartphone-attachable vascular compliance monitoring module. The proposed sensor module measures photoplethysmogram (PPG) and reconstructs an accelerated PPG waveform. The feature points are extracted from the accelerated PPG waves, and vascular compliance is estimated using these extracted features. The module is powered via the smartphone's USB terminal and transmits the acquired waveforms along with vascular compliance values through Bluetooth. The transmitted waveforms and vascular compliance value are displayed through the smartphone application. This work proposes an assessment method for consistency of PPG instrumentation, and it was implemented in a processor of sensor module. The proposed sensor module can be easily attached to smartphone that does not support PPG instrumentation, providing simple measurment and numerical analysis of vascular compliance. To verify the performance of the implemented sensor module, we acquired vascular compliance and pulse pressure data from 29 subjects. Pulse pressure, which serves as a representative indicator of vascular compliance, was obtained using a commercial blood pressure monitor. The analysis results showed that the Pearson coefficient between vascular compliance and pulse pressure was 0.778, confirming a relatively high correlation between two metrics.

• Journal of Life Science
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• v.13 no.5
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• pp.634-641
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• 2003

In order to examine whether arsenic, one of environmental stress, contribute to augumentation and relaxation of rat aorta, this study was performed in vivo and in vitro, using intacted or denuded rats aorta ring preparation, respectively. The carotid arterial pressure was recorded on an ink-writing physiograph(Grass Co. 79E) connected to strain gauge. The contractile response of vascular ring with or without endothelium preparation isolated from rat were determined in organ bath and was recorded on physiograph connected to isometric transducer. Vasopressin-,and phenylephrine- induced increase in arterial pressure significantly enhanced in arsenic-treated rats; increase of 19.1%, and 46.6%, respectively. Vascular contractile response was measured in vitro preparations exposed to 0, 0.5, 1, 2 and 4 mM of arsenic for 1, 3, 5 and 8 hours. The dose-vascular responses of phenylephrine augmented by increasing dose of arsenic in the strips exposed to arsenic for 8 hours, and did not augmented for 1, 3, 5 hours. The phenomenon was not affected by strips denuded endothelium. And the response of relaxation of rat aorta induced by nitroprusside was not influenced by arsenic stress, but acetylcholine was a little increased. compared to that of control. There were no significant difference in relaxation between control and arsenic treated rings with endothelium or denuded. All of the results, phenyleprine-induced vascular contraction was significantly enhanced in 4 mM arsenic-treated rat aortic rings compared with control, whether endothelium was present or denuded at 8 hours after arsenic treatment. It may be a mechanism by which long-term arsenic stresses play a role in development of hypertension.

• Proceedings of the Korean Fiber Society Conference
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• 1999.04a
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• pp.67-70
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• 1999

• Journal of the KSME
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• v.55 no.3
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• pp.38-41
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• 2015

이 글에서는 무세포 경계층(red blood cell free layer)의 생리학적 중요성 및 미세순환(microcirculation)에서 이루어지는 가스교환 예측을 위한 수치해석모델(numerical simulation) 개발을 소개하고자 한다.

• Journal of Chest Surgery
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• v.34 no.3
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• pp.240-242
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• 2001

임심 중 심폐바이패스를 사용하는 개심수술은 산모뿐 아니라 태아계에도 영향을 끼치기 때문에 중요하다. 임신 중 항응고제 투여을 부적절하게 하여 기계판막 기능부전이 초래된 임신 31주의 산모에서 심장 재수술에 앞서 제왈절개로 태아 출산 후 20시간 뒤 산모의 개시수술을 성공적으로 시행하였기에 보고하는 바이다.

• Korean Journal of Poultry Science
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• v.31 no.1
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• pp.61-71
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• 2004

현대인이 섭취하고 있는 식품 중에서 계란의 콜레스테롤처럼 많은 연구자의 관심을 끌었던 성분도 많지 않을 것이다. 콜레스테롤 섭취와 심장혈관계 질환과의 연관성에 대한 우려는 계란이 영양적으로 매우 우수한 식품임에도 불구하고 그 소비에 막대한 지장을 주고 있다.(중략)

• The Monthly Diabetes
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• s.239
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• pp.17-19
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• 2009

불행히도 고혈당은 미세혈관계에도 영향을 미쳐 실명의 가장 흔한 원인이 된다. 이에 본 당뇨캠프 참가자들의 열띤 관심으로 삼성서울병원 안과 강세웅 교수의 '당뇨인의 안과질환'이란 제목의 강의 이루어졌다.

• Journal of the korean veterinary medical association
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• v.46 no.11
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• pp.1038-1046
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• 2010

말과 자동차는 서로 닮은 게 몇 가지 있는데, 순환기계 및 호흡기계는 말의 엔진을 구성하고 말이 소화 시키는 사료는 자동차의 연료와 같으며, 연료는 근육에 힘을 내는 영양적 에너지로 바뀐다. 호흡기계는 대사를 촉진하기 위해 산소를 제공하고 심장혈관계 또는 순환기계는 산소와 영양소를 조직에 운반할 뿐만 아니라 엔진이 작동하면서 생긴 노폐물도 제거한다.

• Progress in Medical Physics
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• v.2 no.2
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• pp.183-192
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• 1991

Ophthalmoscopy following the intravenous injection of fluorescein has gained great diagnostic importance in ophthalmology. This technique provides sequential evaluation of the anatomic and physiologic status of the choroidal and retinal vasculature. In order to detect the changes between fluorescein ocular fundus image frames, the direct subtraction of the two frames is inadequate because of geometric distortions and background gray level differences in two images. In this study, a scheme for the correction of the geometric distortions is proposed. Precise control point coordinate values for transformation functions are manually determined after the process including a series of blood vessel detection and thinning, and one frame is mapped to another, and then a geometric distortion corrected image is obtained. When the corrected image is used in interframe change detections, a sucessful result is ensured.

• Journal of Chest Surgery
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• v.34 no.6
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• pp.502-505
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• 2001

Pulmonary sequestration is an abnormal lung tissue that does not communicate with tracheobronchial tree, and that receives blood supply from anomalous arteries. Pulmonary sequestration is divided into two anatomical forms, intralobar and extralobar. Extralobar pulmonary sequestration is usually located between the diaphragm and the lower lobe and has systemic arterial supply and venous drainage, and most patients are diagnosed in their infancy. We report an extralobar pulmonary sequestration located between the right upper lobe and the lower lobe in a 48-year-old female adult, which has anomalous blood supply from the right pulmonary artery and venous drainage directly into the left atrium.