• The Journal of Korean Physical Therapy
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• v.17 no.2
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• pp.126-147
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• 2005

TCD(transcranial doppler, TCD) units is a equipment that measure a blood flow velocity in the middle cerebral artery(MCA), anterior cerebral artery(ACA), posterior cerebral artery(PCA), and vertebral artery(VA). The aim of this study was to determine the influence on cerebral blood flow velocity according to different stimulation frequency of interferential currents. 50 patients who has a cervical pain were participated in this study and randomly divided into one of the three experimental, placebo, and control group: (1)IFS 1; $10{\sim}30Hz$ was applied, (2)IFS 2; $30{\sim}50Hz$ was applied, (3)IFS 3; $50{\sim}100Hz$ was applied, (4)placebo; suction only applied, and (5)control; neither suction nor interferential stimulation applied. In the IFS groups, interferential stimulations were applied through four suction electrodes application from the 5th cervical to the 1st thoracic level. The results were as follow; 1. MCA was statistically significant with IFS 1, IFS 2, IFS 3, and Placebo group(p<0.05), But there was no statistical significance between IFS 1 and IFS 3 group(p>0.05). 2. ACA was statistically significant with IFS 1, IFS 2, and IFS 3 group(p<0.05). And IFS 1 was more statistical significance than IFS 3 group on ACA(p<0.05). 3. PCA was statistically significant with IFS 1, IFS 2, and IFS 3 group(p<0.05). And IFS 1 was more statistical significance than IFS 3 group on PCA(p<0.05). 4. VA was statistically significant with IFS 1, IFS 2, and IFS 3 group(p<0.05). And IFS 1 was more statistical significance than IFS 3 group on VA(p<0.05).

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.8
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• pp.511-517
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• 2016

Three-dimensional models of stenosis blood vessels were prepared using a 3D printer. The models included a straight pipe with axisymmetric stenosis and a pipe that was bent $10^{\circ}$ from the center of stenosis. A refractive index matching method was utilized to measure accurate velocity fields inside the 3D tubes. Three different pulsatile flows were generated and controlled by changing the rotational speed frequency of the peristaltic pump. Unsteady velocity fields were measured by a time-resolved particle image velocimetry method. Periodic shedding of vortices occurred and moves depended on the maximum velocity region. The sizes and the positions of the vortices and symmetry are influenced by mean Reynolds number and tube geometry. In the case of the bent pipe, a recirculation zone observed at the post-stenosis could explain the possibility of blood clot formation and blood clot adhesion in view of hemodynamics.

• Journal of Periodontal and Implant Science
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• v.52 no.1
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• pp.65-76
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• 2022

Purpose: The present study measured changes in arteriolar and venular capillary flow and structure in the gingival tissues during the development of plaque-induced gingival inflammation by combining dynamic optical coherence tomography (OCT), laser perfusion, and capillaroscopic video imaging. Methods: Gingival inflammation was induced in 21 healthy volunteers over a 3-week period. Gingival blood flow and capillary morphology were measured by dynamic OCT, laser perfusion imaging, and capillaroscopy, including a baseline assessment of capillary glycocalyx thickness. Venular capillary flow was estimated by analysis of the perfusion images and mean blood velocity/acceleration in the capillaroscopic images. Readings were recorded at baseline and weekly over the 3 weeks of plaque accumulation and 2 weeks after brushing was resumed. Results: Perfusion imaging demonstrated a significant reduction of gingival blood flow after 1 and 2 weeks of plaque accumulation (P<0.05), but by 3 weeks of plaque accumulation there was a more mixed picture, with reduced flow in some participants and increased flow in others. Participants with reduced flux at 3 weeks also demonstrated venular-type flow as determined by perfusion images and evidence of the development of venular capillaries as assessed by the velocity/acceleration ratio in capillaroscopic images. After brushing resumed, these venular capillaries were broken down and replaced by arteriolar capillaries. Conclusions: After 3 weeks of plaque accumulation, there was wide variation in microvascular reactions between the participants. Reduced capillary flow was associated with the development of venular capillaries in some individuals. This is noteworthy, as an early increase in venous capillaries is a key vascular feature of cardiovascular disease, psoriasis, Sjögren syndrome, and rheumatoid arthritis-diseases with a significant association with the development of severe gingival inflammation, which leads to periodontitis. Future investigations of microvascular changes in gingival inflammation might benefit from accurate capillary flow velocity measurements to assess the development of venular capillaries.

• Proceedings of the Korean Magnestics Society Conference
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• 2012.11a
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• pp.140-142
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• 2012

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.19 no.1
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• pp.135-144
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• 2006

Objective : The purpose of this study was to know the clinical effects of hydrotherapy based Ultrasonic spa using SoPung-Tang on pulse wave velocity in patients with sequelae of CVA. Methods : PWV(Pulse wave velocity), Bio Chemistry, Hematology, Blood Pressure were investigated in 20 patients(Experimental group 13, Control group 7) who have been in Semyung Oriental medicine hospital from December 2005 to February 2006. Results : 1. In experimental group, Rt PWV diminished 4.8%, Lt PWV 5.1%. 2. In control group, Rt PWV diminished 3.3%, Lt PWV 1.8%. Conclusion : Hydrotherapy based Ultrasonic spa using SoPung-Tang showed useful effects in patients with sequelae of CVA.

• International Journal of Vascular Biomedical Engineering
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• v.1 no.1
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• pp.3-12
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• 2003

Ultrasonic pulsed Doppler velocimetry has become a standard international method of classifying carotid disease. Because the measured angle adjusted velocity increases as the Doppler angle increases, examinations should be performed at a convenient standard Doppler examination angle. An angle of 60 degrees is achievable throughout most examinations. Multiple Doppler viewing angles allow the acquisition of velocity vectors during the cardiac cycle, revealing the complex velocity patterns. Ultrasonic velocimetry (whether Doppler or time domain) is based on changes in the phase of the ultrasound echo. Other examinations can be done based on the echo phase. Slow motions of organs such as the brain can be used to monitor changes in edema. Measurements of tissue strain due to the pulsatile filling of the arterioles. This plethysmographic imaging method can display differences in tissue perfusion because of different tissue types and changes in autonomic activity.

• International Journal of Vascular Biomedical Engineering
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• v.4 no.2
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• pp.13-18
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• 2006

Direct injection of a fibrinolytic agent to the intra-arterial thrombosis may increase the effectiveness of thrombolysis by enhancing the permeation of thrombolytic agents into the blood clot. Permeation of fibrinolytic agents into a clot is influenced by the surface pressure, which is determined by the injection velocity of fibrinolytic agents. Computational fluid dynamic methods were used in order to predict clot lysis for different jet velocities and nozzle arrangements. Firstly, thrombolysis of a clot was mathematically modeled based on the pressure and lysis front velocity relationship. Direct injection of a thrombolytic agent increased the speed of thrombolysis significantly and the effectiveness was increased as the ejecting velocity increased. The nine nozzles model showed about 20% increase of the lysed volume, and the one and seventeen nozzles models did not show significant differences. Secondly, thrombolysis was modeled based on the enzyme transport and the fluid flow equations, and quasi steady numerical analysis was performed. Clot lysis efficiency was also increased as injection velocity increased.

• Journal of Korean Neurosurgical Society
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• v.30 no.8
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• pp.970-975
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• 2001

Objective : By conducing a review of clinical outcomes for patients with aneurysm treated using current microneurosurgical techniques and intensive care unit management, we speculated that grading systems based only on clinical condition or CT finding after admission failed to provide a significant stratification of outcome between individual grades of patients, because these systems did not include the factor for postoperative vasospasm. We hypothesized that postoperative blood flow velocity could have a significant impact on outcome prediction for patients surgically treated for intracranial aneurysms. Methods : We conducted a analysis on patient- and lesion-specific factors that might have been associated with outcome in a series of 55 aneurysm operations performed with measurements of blood-flow velocity with transcranial Doppler ultrasonography(TCD). In the new scale(NS) score system, 1 point is assigned additionally for the case with Hunt and Hess(H-H)/World Federation of Neurological Surgeons(WFNS) Grade IV or V, Fisher Scale(FS) score 3 or 4, aneurysm size greater than 10mm, patient age older than 60 years, blood-flow velocity higher than 120cm/sec, and posterior circulation lesion. By adding the total points, a 6-point scale score(score 0-6) is obtained. Results : Age of patient, size of aneurysm, clinical condition(H-H grade and WFNS), FS score, and blood flow velocity(TCD 1day after operation) were independently and strongly associated with long-term outcome. When NS scores were applied to 55 patients with at least 6 months follow-up, the correlation of individual scores with outcome was strongly validated the retrospective findings. Conclusion : It was speculated that TCD could be used to assess postoperative vasospasm and to monitor noninvasively the patients with aneurysmal SAH. This NS score system is easy to apply, divide patients into groups with different outcome, and is comprehensive, allowing for more accurate prediction of surgical outcome.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.318-318
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• 2003

The current study was performed to observe the effects of Panax ginseng (PG) and P. quinquefolium (PQ) on hemodynamics such as blood flow rate (BF), blood flow velocity (BV), heart rate (HR), systolic blood pressure (SBP), and diastolic blood pressure (DBP) and body temperature (BT) in healthy young men. This is a randomized, single-blind study observed during 6 hrs after orally single administration of PG and PQ groups. (omitted)

• Proceedings of the KIEE Conference
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• 2007.04a
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• pp.77-79
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• 2007

The purpose of this study was to suggest a new detection method for early diagnosing diabetic neuropathic foot by obtaining a ratio of toe to figer blood flow using photoplethysmography(PPG). Nerve conduction velocity (NCV) has been routinely used for diagnosing neuropathic foot, but it applies strong electric stimulus to peripheries resulting in stress and pain. The blood flow ratio of diabetic neuropathy(0.96${\pm}$0.20) was significantly higher in comoarison to normal control group(0.46${\pm}$0.15, left : p<0.05, right : p<0.05) and non-neuropathy diabetic group(0.49${\pm}$0.21, left: p<0.05. right: p<0.05).