• Journal of the Korea Society of Computer and Information
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• v.26 no.4
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• pp.29-37
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• 2021

In this paper, we propose a deep learning-based retinal vessel segmentation model for handling multi-scale information of fundus images. we integrate the selective kernel convolution into U-Net-based convolutional neural network. The proposed model extracts and segment features information with various shapes and sizes of retinal blood vessels, which is important information for diagnosing eye-related diseases from fundus images. The proposed model consists of standard convolutions and selective kernel convolutions. While the standard convolutional layer extracts information through the same size kernel size, The selective kernel convolution extracts information from branches with various kernel sizes and combines them by adaptively adjusting them through split-attention. To evaluate the performance of the proposed model, we used the DRIVE and CHASE DB1 datasets and the proposed model showed F1 score of 82.91% and 81.71% on both datasets respectively, confirming that the proposed model is effective in segmenting retinal blood vessels.

• Annals of Clinical Neurophysiology
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• v.1 no.1
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• pp.47-54
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• 1999

The Doppler in neurosonologic examination could be applied to blood flow to determine its movement, the direction of its movement, and how fast it is. Indicies of the Doppler study denoted velocity, direction, and amount of RBC in the examined vessel. Systolic. diastolic, and mean blood flow velocities represent velocity of RBCs in a sample volume. Blood flow direction to the probe means direction of RBC to the probe. Size of amplitude displays toe amount of the RBCs passing the sample volume. Spectral broadening means presence of turbelence. The RBC movements and hemodynamics at the examined vessels can be estimated by analysis of Doppler indicies The formation and meaning of each of neurosonologic Doppler study is described in the present review.

• Journal of Oral Medicine and Pain
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• v.21 no.1
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• pp.79-87
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• 1996

The purpose of this study was to assess the vascular changes after thermophysical therapies using ice pack and ultrasound, investgate the mechanism of peripheral vasodilation by sympathetic nerve, and to observe the effects of the ergotamine to the thermophysical therapy. The author had used 16 healthy rabbits which were divided into 2 groups : with and without administration of ergotamine. Experimental animals were sacrificed 5, 10, 20 minutes after experiment, and were examined with gross and stereoscope of resin casting blood vessel models. The results were as follows : 1. Vasodilation was not remarkably found in the group with administration of egrotamine after thermophysical therapy. 2. Vasodilation was remarkably found in the group without administration of ergotamine after thermophysical therapy. 3. Vasodilation was increased in the group without administration of ergotamine, but not remarkably found in the group with administration of ergotamine in lapse of time 4. Thermophysical therapy was most effective to arterioles. Our data suggest that the dilation of peripheral blood vessels from thermophysical therapy was controlled by sympathetic nerve, because the blood vessels did not changed after administration of ergotamines which was a sympathetic nerve blocker.

• Korean Journal of Veterinary Research
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• v.31 no.4
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• pp.381-387
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• 1991

Deer hemal nodes were studied by gross anatomy and light microscopy. Hemal nodes were scattered in the periphery of thoracic and abdominal aortae, and spherical or avoid in shape. A hemal node consisted of a thin capsule and a hilum, and had numerous small subcapsular and deep sinuses distended by a great number of erythrocytes. Although a few lymphatic nodules and tissues were seen in the parenchyma, no typical cortex and medulla was defined. Blood vessels occurred, but lymph vessel was not observed in nodes. The parenchyma of the hemal node consisted of many erythrocytes and lymphocytes, and a few granulocytes, plasma cells megakaryocytes and macrophages. The stroma was composed of reticular cells and fibers. The capsule and trabecula was a collagenous connective tissue with smooth myofibers. The above findings suggest that the hemal nodes are involved in blood storage, blood filtration and immune reaction.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4495-4499
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• 2013

Morinda citrifolia, also known as Great Morinda, Indian Mulberry, or Noni, is a plant belonging to the family Rubiaceae. A number of major chemical compounds have been identified in the leaves, roots, and fruits of the Noni plant. The fruit juice is in high demand in alternative medicine for different kinds for illnesses such as arthritis, diabetes, high blood pressure, muscle ached and pains, menstrual difficulties, headache, heart diseases, AIDS, gastric ulcer, sprains, mental depression, senility, poor digestion, arteriosclerosis, blood vessel problems, and drug addiction. Several studies have also demonstrated anti-inflammatory, antioxidant and apoptosis-inducing effects of Noni in various cancers. Based on a toxicological assessment, Noni juice was considered as safe. Though a large number of in vitro, and, to a certain extent, in vivo studies demonstrated a range of potentially beneficial effects, clinical data are essentially lacking. To what extent the findings from experimental pharmacological studies are of potential clinical relevance is not clear at present and this question needs to be explored in detail before an recommendations can be made.

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.500-503
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• 2011

Blood flow simulations in an idealized carotid bifurcation model with considering wall compliance were carried out to investigate the effect of wall elasticity on the wall shear stress and wall solid stress. Canonical waveforms of flowrates and pressure in the carotid arteries were imposed for the boundary conditions. Comparing to rigid wall model, generally, we could find an increased recirculation region at the carotid bulb and an overall reduced wall shear stress. Also, there was appreciable change of flowrate and pressure waveform in longitudinal direction. Solid and wall shear stress concentration occurs at the bifurcation apex.

• BMB Reports
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• v.49 no.5
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• pp.255-262
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• 2016

The disease known as cerebral cavernous malformations mostly occurs in the central nervous system, and their typical histological presentations are multiple lumen formation and vascular leakage at the brain capillary level, resulting in disruption of the blood-brain barrier. These abnormalities result in severe neurological symptoms such as seizures, focal neurological deficits and hemorrhagic strokes. CCM research has identified 'loss of function' mutations of three ccm genes responsible for the disease and also complex regulation of multiple signaling pathways including the WNT/β-catenin pathway, TGF-β and Notch signaling by the ccm genes. Although CCM research is a relatively new and small scientific field, as CCM research has the potential to regulate systemic blood vessel permeability and angiogenesis including that of the blood-brain barrier, this field is growing rapidly. In this review, I will provide a brief overview of CCM pathogenesis and function of ccm genes based on recent progress in CCM research.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.191-192
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• 2002

Angiotensin I converting enzyme [EC 3.4.15.11 (ACE) is important in the maintenance of blood pressure. The enzyme removes histidyl-leucine from angiotensin I to form the blood-vessel-constricting octapeptide, angiotensin II, and degrades vasodilative bradykinin in blood vessels and stimulates e release of aldosterone in the adrenal cortex. (omitted)

• Journal of the Korean Society of Visualization
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• v.13 no.2
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• pp.28-32
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• 2015

Blood flow simulations in an realistic carotid bifurcation model with considering wall compliance were carried out to investigate the effect of wall elasticity on the wall shear stress and wall solid stress. Canonical waveforms of flow rates and pressure in carotid arteries were imposed for boundary conditions. Compared to a rigid wall model, we found an increased recirculation region at the carotid bulb and an overall reduction of wall shear stress in a compliant model. Additionally, there was appreciable change of flow rate and pressure wave in longitudinal direction. Both solid and wall shear stress concentration occur at the bifurcation apex.

• Proceedings of the Korea Society for Simulation Conference
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• 2003.11a
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• pp.201-206
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• 2003

In clinical practice, CT Angiography is a powerful technique for the visualziation of blood flow in arterial vessels throughout the body. However CT Angiography images of blood vessels anywhere in the body may be fuzzy if the patient moves during the exam. In this paper, we propose a novel technique for removing global motion artifacts in the 3D space. The proposed methods are based on the two key ideas as follows. First, the method involves the extraction of a set of feature points by using a 3D edge detection technique based on image gradient of the mask volume where enhanced vessels cannot be expected to appear, Second, the corresponding set of feature points in the contrast volume are determined by correlation-based registration. The proposed method has been successfully applied to pre- and post-contrast CTA brain dataset. Since the registration for motion correction estimates correlation between feature points extracted from skull area in mask and contrast volume, it offers an accelerated technique to accurately visualize blood vessels of the brain.