• International Journal of Vascular Biomedical Engineering
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• 제2권1호
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• pp.25-30
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• 2004

Catheters are used to measure translesional pressure gradients in the stenosed coronary arteries. Uses of catheters during coronary angioplasty cause flow obstructions. A narrowed flow cross section with catheter effectively introduced a tighter stenosis than the enlarged residual stenoses after balloon angiplasty. Catheters in blood vessels cause pressure gradient rise and blood flow drop during the measurements. In this study, three dimensional computer simulations are conducted to investigate the flow blockage effects due to the catheter obstructions during the coronary angioplasty. The computer simulation models are generated by the data, which are measured by coronary angiogram, and the blood is treated as non-Newtonian fluid. The velocity, pressure, and wall shear stress variations are observed for the estimate of damages of blood vessel. This study is also extended to investigate the effects of stenotic vessel size, and shape and catheter size and location.

• International Journal of Vascular Biomedical Engineering
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• 제4권1호
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• pp.1-8
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• 2006

The x-ray PIV method was improved for measuring quantitative velocity fields of real blood flows using a coherent synchrotron x-ray source. Without using any contrast media or seeding particles, this method can visualize flow pattern of blood by enhancing the phase-contrast and interference characteristics of blood cells based on a synchrotron x-ray imaging mechanism. The enhanced x-ray images were achieved by optimizing the sample-to-scintillator distance, the sample thickness, and hematocrit. The quantitative velocity fields of blood flows inside opaque tubes were obtained by applying a 2-frame PIV algorithm to the x-ray images of the blood flows. The measured velocity field data show typical features of blood flows such as the yield stress effect. The non-Newtonian flow characteristics of blood flows were analyzed using the x-ray PIV method and the experimental results were compared with hemodynamic models.

• Journal of Trauma and Injury
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• 제33권3호
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• pp.140-143
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• 2020

Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been accepted as an adjunct procedure for non-compressible torso hemorrhage in patients with hemorrhagic shock. With appropriate indications, REBOA should be performed for resuscitation regardless of the physician's specialty. Despite its effectiveness in traumatized patients with hemorrhagic shock, performing REBOA has been challenging due to physicians' lack of experience. Even though training in endovascular skills is mandatory, many physicians cannot undergo sufficient training because of the limited number of endovascular simulation programs. Herein, we share simulation video clips, including those of a vascular circuit model for simulation; sheath preparation; long guidewire and balloon catheter preparation; ultrasound-guided arterial access; sheath insertion or upsizing; and balloon positioning, inflation, and migration. The aim of this study was to provide educational video clips to improve physicians' endovascular skills for REBOA.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.821-826
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• 2005

Postprandial hyperglycemia plays an important role in the development of type 2 diabetes and complications associated with the disease such micro-and macro-vascular disease. The present study investigated the effect and action mechanism of a ethanolic extract from the Schizandra chinensis(SC-E) on hypeglycemia in vivo and in vitro. In vitro, SE-E demonstrated a potent inhibitory effects on ${\alpha}-amylase$ activity ($IC_{50}$ : 4 ${\mu}g/ml$). Its inhibition on ${\alpha}-amylase$ was determined to be competitive type. Oral administration of SE-E markedly lowered plasma glucose levels in non-fasted streptozotocin induced diabetic rats (45 mg/kg BW). In addition when it was orally administrated to rats with starch (2g/kg BW), SC-E (50 and 100 mg/kg BW) significantly suppressed the increase of blood glucose levels after starch loading . These results suggest that some edible plants merit further evaluation for clinical usefulness as anti-diabetic drugs.

• Biomolecules & Therapeutics
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• 제2권1호
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• pp.71-76
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• 1994

Anti-inflammatory and analgesic activities and skin irritation of piroxicam patch were investigated. Piroxicam patch increased the pain threshold in rat hind paw inflamed by carrageenan and inhibited writhing induced by acetic acid in mice. Piroxicam patch also inhibited the carrageenan-induced edema in rat hind paw as well as the increased vascular permeability induced by histamine in rats. In adjuvant arthritis of rats, piroxicam patch showed anti-inflammatory effects. Skin irritation of piroxicam patch was tested in Newzealand White rabbits and evaluated by Primary Irritation Index of Draize. The results from skin irritation test showed that piroxicam patch seemed practically non-irritating. The result from the present study indicates that piroxicam may be useful without serious side effects as anti-inflammatory analgesics in this patch form.

• Journal of Nutrition and Health
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• 제26권7호
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• pp.851-857
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• 1993

Atherosclerotic vascular disease is a major cause of the increased morbidity and mortality assciated with diabetes mellitus. The prominent role of nutrition in hypercholesteolemia and atherosclerosis is generally accepted. Diet is a key element in the management of diabetes (type I-IDDM), yet the appropriate diet for patient with diabetes mellitus is not well known. Dietary protein has been shown to have a significant effect on plasma cholesterol levels in both experimental animals and humans. The present experiment was designed to determine the effect of the dietary protein level(20% vs 60%) on plasma glucose concentration, lipids profile, insulin and glucagon levels from non-diabetic and streptozotocin-induced diabetic rats. Results showed that a high protein diet decreased triglyceride concentration in diabetic rats. Also diabetic rats fed a high protein diet were hypocholesterolemic than rats fed a control diet. There were no effects by level of protein on fasting blood glucose concentration and insulin/glucagon ratio. Results from the present study suggest that a high protein diet may be beneficial to control pasma lipids in chemically-induced diabetic rats.

• Journal of Chest Surgery
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• 제44권3호
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• pp.266-268
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• 2011

Cystic adventitial disease is rare, but it is one of the well-recognized causes of non-atherosclerotic arterial stenosis or obstruction. Despite one of its most common symptoms being chronic intermittent claudication, it may be misdiagnosed as arterial embolism when presented with acute ischemic symptoms. Surgical resection is recommended because of recurrence or a low success rate with aspiration or endovascular stent. We performed resection and repair with autologous vein patch for cystic adventitial disease of the popliteal artery of a 57-year-old man presenting with pain, pallor, and paresthesia, without any postoperative complications or recurrence.

• 생명과학회지
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• 제18권6호
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• pp.891-896
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• 2008

The function of mast cells as effector cells in allergy has been extensively studied. Mast cells activated through high affinity IgE-receptor ($Fc{\varepsilon}RI$) release diverse mediators, and lead to smooth muscle constriction, vasodilation, increase of vascular permeability, leukocyte recruitment and activation, mucus secretion, and tissue proliferation and remodeling. However, various other immunological and non-immunological signals can lead to the activation of mast cells. In resent years, mast cells have been identified to be involved in a complex range of immune functions. Mast cells can be important as key players in the regulation of innate as well as adapted immune responses, and may influence the development of allergy, autoimmune disorder and peripheral tolerance. This review summarizes the recent advances in the understanding of effector functions of mast cells in immune responses.

• 한국수의병리학회지
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• 제3권2호
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• pp.73-76
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• 1999

The tissue distribution and cellular localization of viral antigen in the brain of aborted fetus with bovine viral diarrhea virus(BVDV) infection was studied; BVDV antigens was detected in spleen, kidney, lung, eyelid as well as brain. In the brain, the virus was recognized in neurons and non-neuronal cells in the cerebellum and cerebrum. Many cells in the superficial layer and occasional Purkinje cells had BVDV antigens. As well, BVDV was also found in the perivascular cells, vascular endothelial cells and smooth muscle cells in the vessels and neuroglial cells in the white matter. This finding suggests that BVD virus favors infect progenitor cells in the brain, notably in the superficial layer of cerebellum, and damage normal development of cerebellum, which leads to cerebellar hypoplasia.

• Animal cells and systems
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• 제7권3호
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• pp.261-264
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• 2003

Leiden), no mutation was detected in either group. Allele frequencies of A2379G and G2391 A mutations were not significantly different between CAD patients and controls. Non-Caucasian populations have a considerably lower factor Ⅴ Leiden allele frequency than Caucasian populations. Thus, it may be due to differences in the genetic background as well as environmental factors.