• 제목/요약/키워드: Blood vessels

검색결과 904건 처리시간 0.027초

유정란 태아외부혈관 내부 혈액유동에 대한 혈류역학적 연구 (Hemodynamic Analysis of Blood Flows in the Extraembryonic Blood Vessels of Chicken Embryos)

  • 이정엽;이상준
    • 한국전산유체공학회:학술대회논문집
    • /
    • 한국전산유체공학회 2008년도 춘계학술대회논문집
    • /
    • pp.6-9
    • /
    • 2008
  • Analyzing the characteristics of blood flow in the blood vessels is very important to diagnose the circulatory diseases. In order to investigate the hemodynamic characteristics in vivo, the measurements of blood flows inside the extraembryonic arterial and venous blood vessels of chicken embryos were carried out using an in vivo micro-PIV technique. The circulatory diseases are closely related with the formation of abnormal hemodynamic shear stress regions, thereby it is important to get blood velocity and vessel's morphological information according to the vessel configuration and the flow conditions. In this study, the flow images of RBCs in blood vessels were obtained using a high-speed CMOS camera with a spatial resolution of approximately 14.6${\mu}$m${\times}$14.6${\mu}$m in the whole circulation network of blood vessels. The blood flows in the veins and arteries show steady laminar and unsteady pulsatile flow characteristics, respectively. The mean blood flows merged (in veins) and bifurcated (in arteries) smoothly into the main blood vessel and branches, respectively, without any flow separation or secondary flow which accompanying large variation of shear stress. Vorticity was high in the inner regions for both types of vessels, where the radius of curvature varied greatly. The instantaneous flows in the arterial blood vessels showed noticeable pulsatility due to the heart beat, and the main features of the velocity waveforms, including pulsatile shape, retrograde flow, mean velocity, maximum velocity and pulsatile frequency, were significantly dependent on the pulsatile condition which dominates the arterial blood flow. In near future, these in vivo experimental results of blood flow measured in various extraembryonic blood vessels would be very useful to understand the hemodynamic characteristics of human blood flows and various blood flow researches for clinically useful hemodynamic discoveries as well.

  • PDF

$\ll$황제내경(黄帝内经)$\gg$ 혈맥이론탐토(血脉论探讨) (Research on The Theory of Blood Vessels in "Hwangjenaegyeong(黃帝內經)")

  • 국보조;김효철
    • 대한한의학원전학회지
    • /
    • 제22권4호
    • /
    • pp.217-220
    • /
    • 2009
  • In "Hwangjenaegyeong(黃帝內經)", the name of blood vessels is closely related to images of the river, and the word for blood vessel contains the following meaning, such as blood vessel, blood wind as well as blood stasis and so on. In a physiological perspective, the unobstructed blood vessel and normal operation blood are important symbols of health, for blood is the basis for human survival, physical activity and mental activity. In pathology, the external cold, excessive seven emotions and a biased diet can cause many kinds of abnormalities of the blood vessels, which can in turn become causes for a variety of diseases. The theory of blood vessels in "Hwangjenaegyeong" can provide guidance for diagnosis and treatment of cardiovascular diseases in practice.

  • PDF

In vitro and in vivo Application of PLGA Nanofiber for Artificial Blood Vessel

  • Kim, Mi-Jin;Kim, Ji-Heung;Yi, Gi-Jong;Lim, Sang-Hyun;Hong, You-Sun;Chung, Dong-June
    • Macromolecular Research
    • /
    • 제16권4호
    • /
    • pp.345-352
    • /
    • 2008
  • Poly(lactic-co-glycolic acid) (PLGA) tubes (5 mm in diameter) were fabricated using an electro spinning method and used as a scaffold for artificial blood vessels through the hybridization of smooth muscle cells (SMCs) and endothelial cells (ECs) differentiated from canine bone marrow under previously reported conditions. The potential clinical applications of these artificial blood vessels were investigated using a canine model. From the results, the tubular-type PLGA scaffolds for artificial blood vessels showed good mechanical strength, and the dual-layered blood vessels showed acceptable hybridization behavior with ECs and SMCs. The artificial blood vessels were implanted and substituted for an artery in an adult dog over a 3-week period. The hybridized blood vessels showed neointimal formation with good patency. However, the control vessel (unhybridized vessel) was occluded during the early stages of implantation. These results suggest a shortcut for the development of small diameter, tubular-type, nanofiber blood vessels using a biodegradable material (PLGA).

Tensile Characteristics and Behavior of Blood Vessels from Human Brain in Uniaxial Tensile Test

  • Suh, Chang-Min;Kim, Sung-Ho;Ken L. Monson;Werner Goldsmith
    • Journal of Mechanical Science and Technology
    • /
    • 제17권7호
    • /
    • pp.1016-1025
    • /
    • 2003
  • The rupture of blood vessels in the human brain results in serious pathological and medical problems. In particular, brain hemorrhage and hematomas resulting from impact to the head are a major cause of death. As such, investigating the tensile behavior and rupture of blood vessels in the brain is very important from a medical point of view. In the present study, the tensile characteristics of the blood vessels in the human brain were analyzed using a quasi-static uniaxial tensile test, and the properties of the arteries and veins compared. In addition, to compare the tensile behavior and demonstrate the validity of the experimental results, blood vessels from the legs of pigs were also tested and analyzed. The overall results were in accordance with the histological structures and previous medical reports.

3차원 골격곡선을 이용한 가상혈관 탐색 방안 (Virtual Navigation of Blood Vessels using 3D Curve-Skeletons)

  • 박상진;박형준
    • 한국CDE학회논문집
    • /
    • 제22권1호
    • /
    • pp.89-99
    • /
    • 2017
  • In order to make a virtual endoscopy system effective for exploring the interior of the 3D model of a human organ, it is necessary to generate an accurate navigation path located inside the 3D model and to obtain consistent camera position and pose estimation along the path. In this paper, we propose an approach to virtual navigation of blood vessels, which makes proper use of orthogonal contours and skeleton curves. The approach generates the orthogonal contours and the skeleton curves from the 3D mesh model and its voxel model, all of which represent the blood vessels. For a navigation zone specified by two nodes on the skeleton curves, it computes the shortest path between the two nodes, estimates the positions and poses of a virtual camera at the nodes in the navigation zone, and interpolates the positions and poses to make the camera move smoothly along the path. In addition to keyboard and mouse input, intuitive hand gestures determined by the Leap Motion SDK are used as user interface for virtual navigation of the blood vessels. The proposed approach provides easy and accurate means for the user to examine the interior of 3D blood vessels without any collisions between the camera and their surface. With a simple user study, we present illustrative examples of applying the approach to 3D mesh models of various blood vessels in order to show its quality and usefulness.

EFFECT OF ARSENIC ON ACETYLCHOLINE-INDUCED RELEXATION IN BLOOD VESSELS IN VITRO AND IN VIVO

  • Lee, Moo-Yeol;Chung, Seung-Min;Bae, Ok-Nam;Chung, Jin-Ho
    • 한국독성학회:학술대회논문집
    • /
    • 한국독성학회 2002년도 Current Trends in Toxicological Sciences
    • /
    • pp.106-106
    • /
    • 2002
  • Several epidemiological studies suggested that arsenic exposure was strongly correlated with the development of cardiovascular disease such as hypertension. In order to examine whether arsenic affects vasomotor tone in blood vessels, we investigated the effect of arsenic on agonist-induced vasorelaxation using the isolated rat aortic rings in in vitro organ bath system.(omitted)

  • PDF

ARSENIC-INDUCED DYSFUNCTION IN RELAXATION OF BLOOD VESSELS

  • Lee, Moo-Yeol;Jung, Byung-In;Chung, Seung-Min;Bae, Ok-Nam;Chung, Jin-Ho
    • 한국독성학회:학술대회논문집
    • /
    • 한국독성학회 2002년도 Molecular and Cellular Response to Toxic Substances
    • /
    • pp.155-155
    • /
    • 2002
  • Several epidemiological studies have suggested that exposure to arsenic is strongly correlated with the development of cardiovascular diseases such as hypertension. To determine whether arsenic affects vasomotor tone in blood vessels, we investigated the effect of arsenic on vasorelaxation using isolated rat aortic rings in an organ bath system.(omitted)

  • PDF

생약(生藥) 복합제제(複合製劑)의 약효(藥效) 연구(硏究)(제21보)(第21報) -이진탕(二陳湯)이 중추신경계(中樞神經系), 혈관(血管) 및 혈압(血壓)에 미치는 영향(影響)- (Studies on the Efficacy of Combined Preparation of Crude Drugs(XXI) -Effects of Yijin-Tang on the Central Nervous System, Blood Vessels and Blood Pressure-)

  • 홍남두;장인규;류성규;김창민
    • 생약학회지
    • /
    • 제16권1호
    • /
    • pp.26-30
    • /
    • 1985
  • These studies were conducted to investigate the effect of Yijin-tang on the anticonvulsion, analgesic, sedative actions, effect on blood vessels and blood pressure. The result of these studies was summarized as follows; Suppressive action was shown on convulsion due to cerebrocortical causes, but no such actions were noted either myelic or diencephaltic causes in mice. Analgesic and sedative actions were significantly recognized in mice. Increasing of blood pressure and vasocontractive actions were noted.

  • PDF

안저영상 해석을 위한 특징영역의 분할에 관한 연구 (A Study on the Feature Region Segmentation for the Analysis of Eye-fundus Images)

  • 강전권;한영환
    • 대한의용생체공학회:의공학회지
    • /
    • 제16권2호
    • /
    • pp.121-128
    • /
    • 1995
  • Information about retinal blood vessels can be used in grading disease severity or as part of the process of automated diagnosis of diseases with ocular menifestations. In this paper, we address the problem of detecting retinal blood vessels and optic disk (papilla) in eye-fundus images. We introduce an algorithm for feature extraction based on Fuzzy Clustering algorithm (fuzzy c-means). A method of finding the optic disk (papilla) is proposed in the eye-fundus images. Additionally, the inrormations such as position and area of the optic disk are extracted. The results are compared to those obtained from other methods. The automatic detection of retinal blood vessels and optic disk in the eye-rundus images could help physicians in diagnosing ocular diseases.

  • PDF

혈관조형술과 조직학적 방법을 이용한 랫드 꼬리의 혈관구조 규명 (Re-Examination of Blood Vessels of Rat Tail Using Angiographic and Histological Methods)

  • 이경선;정의숙;허승호;서진희;이민수;엄기동;최양규
    • 한국임상수의학회지
    • /
    • 제27권2호
    • /
    • pp.159-162
    • /
    • 2010
  • 랫드 꼬리는 연속적인 채혈을 위해서 주로 이용되는 채혈부위로 꼬리 절개법, 꼬리 절단법, 꼬리 천자 등의 방법을 통해 채혈이 이루어지고 있다. 하지만, 랫드 꼬리에 대한 혈관 구조는 아직 잘 밝혀져 있지 않다. 그래서 본 연구에서는 독성학이나 약리학에서 가장 많이 이용되는 폐쇄군인 Sprague-Dawley 랫드 꼬리의 혈관구조 규명하기 위해 혈관조형술과 면역조직학적인 방법을 실시하였다. 그 결과 SD 랫드 꼬리는 한 개의 등쪽 정맥과 두개의 외측정맥, 한쌍의 배쪽 정맥과 동맥이 존재했다. 그러므로, 본 연구는 SD 랫드 꼬리를 이용해서 채혈을 하고자 하는 연구자들이 꼬리의 혈관구조를 이해하고, 그 연구 목적에 맞게 채혈부위와 방법을 선택하는데 도움이 될 것으로 생각된다.