• Journal of Korean Society of Transportation
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• v.17 no.2
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• pp.127-135
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• 1999

Most existing progression bandwidth models maximize the single or multi weighted sum of bandwidths in the both directions to improve traffic mobility on an arterial, but they cannot be applied to general networks. Even though a few models formulating a looped network problem cannot be applied to networks have not loops. Also they have some defects in optimizing phase sequences. Therefore, the objective of this study is to develope a mathematical formulation of the synchronization problem for a general traffic network. The goal is achieved successfully by introducing the signal phasing for each movement and expanding the mixed integer linear programming of MAXBAND. The experiments indicate that the proposed model can formulate the general traffic network problem mere efficiently than any other model. In conclusion, this model may optimize signal time to smooth progression in the general networks.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.5
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• pp.1235-1242
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• 2003

This study was performed for the investigation of vasodilatory effects of Crataegus pinnatifida Bunge and for isolation and structure determination of the constituent from the active fraction. The fruits of this herbal drug were extracted with 80% methanol, then fractioned successively with methylene chloride, ethylacetate and n-butanol. Among the fractions, ethyl acetate fraction exhibited the most effective vascular relaxation against phenylephrine-induced arterial contraction. In order to isolate the active constituent by activity-guided fractionation, this fraction was chromatographed on silica gel to yield seven subfractions. Among the subfractions, the active one showing the most potent vascular relaxation activity was further separated by prep. HPLC with reversed phase Microsorb C-18 column using 1 % acetic acid and methanol gradient solvent system to afford one pure compound, which revealed a potent vasodilatory effect. Instrumental analyses (NMR and mass spectrometry) of the isolated constituent indicated this compound to be (-)-epicatechin. The vasodilatory action mechanism of this compound should be further investigated.

• Journal of Trauma and Injury
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• v.26 no.1
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• pp.22-25
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• 2013

Severe blunt abdominal trauma frequently involves the liver. The development of nonsurgical treatment of liver trauma has led to more frequent appearance of unusual complications. A hepatic arterioportal fistula (APF) is a rare complication of liver trauma. We present a case of traumatic APF in a patient with liver trauma. A 31-year-old male visited our emergency department with pain in the right upper abdomen following a traffic accident. Initial physical exam and abdominal computed tomography (CT) revealed liver laceration with hemoperitoneum. An abdominal CT obtained on day 11 revealed early opacification of the right portal vein on the arterial phase. After we had come to suspect an APF of the liver, its presence was confirmed on angiography. It was subsequently managed by using transcatheter coil embolization. In patients with portal hypertension and no evidence or history of cirrhosis, one should consider an APF as a potential etiology if history of liver biopsy or penetrating trauma exists. In a patient with liver trauma, serial abdominal CT is important for early detection and treatment of an APF.

• Journal of the Korean Magnetics Society
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• v.22 no.1
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• pp.27-31
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• 2012

Two radially arterial pulses of both hands using the prototype of a clamping clip pulsimeter equipped with permanent magnet and Hall device are compared and analyzed. The phase difference of two pulse wave signals is dominantly presented from the simultaneous measuring clinical pulse wave signals for twenty two male participants at their 20's. It is possible to analyze that the fast and slow pulse wave for right hand and left hand depend on the muscle property of arms rather than the total length of blood vessel due to cardiovascular circulatory system.

• The Korean Journal of Physiology
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• v.20 no.2
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• pp.236-248
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• 1986

Alterations of renin-angiotensin system have been suggested as one of the mechanisms increasing arterial blood pressure in experimental and clinical hypertension. But the exact nature of high blood pressure in the early and late phase of renal hypertension is still controversial. To clarify the nature of renin release in both unclipped and clipped kidney of two kidney one clip Goldblatt lypertensive rat, experiments have been done in kidney slices, which were obtained from the rats of 3 and 7 days of operation. Basal rate of renin release was suppressed in unclipped kidney slices compared to clipped kidney Norepinephrine increased renin release from unclipped kidney slices, but not from clipped kidney slices. Suppressions by angiotensin Il and arginine vasopressin of renin release were attenuated in the clipped kidney slices compared to unclipped and sham-operated kidney slices. Increases by verapamil and trifluoperazine of renin release were attenuated in the clipped kidney slices compared to unclipped and sham-operated kidney slices. These results suggest that the negative feedback control mechanism of the renin-angiotensin system by angiotensin Il and arginine vasopressin is attenuated in the clipped kidney of two kidney one clip Goldblatt hypertensive rat, and that one of the altered mechanisms may be caused by certain regulatory changes of intracellular calcium and/or calcium-calmodulin complex in the juxtaglomerular cells.

• Journal of Yeungnam Medical Science
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• v.35 no.1
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• pp.127-129
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• 2018

Fitz-Hugh-Curtis syndrome (FHCS) is characterized by inflammation of the perihepatic capsules associated with the pelvic inflammatory disease (PID). FHCS is not a serious disease, but if not treated properly, it can result in increased medical costs, prolonged treatment, and dissatisfaction with treatment. However, early recognition of FHCS in the emergency department can be difficult because its symptoms or physical findings may mimic many other diseases. Although contrast-enhanced computed tomography (CECT) is the useful imaging modality for recognition of FHCS, it is available only when a high suspicion is established. We performed point-of-care ultrasonography in an 18-year-old woman who had a sharp right upper quadrant (RUQ) abdominal pain without PID symptoms and found a thickened or three-layer hepatic capsule. These findings coincided with areas showing increased hepatic capsular enhancement in the arterial phase of CECT. These results show that if the thickened or three-layer hepatic capsule without evidence of a common cause of RUQ pain is observed on ultrasonography in women of childbearing age with RUQ abdominal pain, the physician can consider the possibility of FHCS.

• Journal of Medicine and Life Science
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• v.19 no.3
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• pp.125-129
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• 2022

Patients with nephrotic syndrome (NS) are generally known to be at greater risk for thrombosis, with arterial thrombosis-related complications being relatively rare compared to venous thrombosis-related complications. This report describes a 46-year-old male with historically proven minimal change disease (MCD) complicated by acute aortoiliac thrombosis. He had been diagnosed with MCD 8 months previously and was treated successfully with steroids. He was prescribed a second course of high-dose steroids (prednisolone 1 mg/kg/day) due to a relapse of MCD at the outpatient clinic 8 days before the emergency department visit. The patient presented with severe pain in both lower limbs and was diagnosed with aortoiliac thrombosis that developed during high-dose steroid treatment. He subsequently underwent surgical thromboembolectomy. Hypoalbuminemia has the strongest association with the risk of thromboembolism. According to international clinical practice guidelines, anticoagulant therapy is recommended when serum albumin is ≤2-2.5 g/dL. However, as serum albumin levels may be relatively high in the early phase of NS, as in this case report, an individualized anticoagulation strategy for each patient should be considered, regardless of serum albumin levels.

• Journal of Digestive Cancer Research
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• v.5 no.1
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• pp.50-54
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• 2017

Pancreatic neuroendocrine tumors are rare pancreatic neoplasms comprising 1-2% of all pancreatic tumors and typically present high attenuating mass on arterial and venous phase images, due to their rich capillary network. A 70-year-old South Korean female visited our hospital presenting with jaundice and dark urine color. She had received an operation for treatment of small bowel perforation seven years ago. On physical examination, icteric sclera was observed but otherwise unremarkable. Laboratory tests were abnormal liver function test and suspected obstructive jaundice. Computed tomography revealed 4 cm sized cystic mass lesion with homogeneous low attenuation in the head of pancreas and distal common bile duct was compressed by the mass. During review of past medical records, we found that the mass was observed and measured about 1.7 cm seven years ago. To resolve obstructive jaundice, pylorus preserving pancreaticoduodenectomy was performed and diagnosed with well differentiated pancreatic neuroendocrine carcinoma with intermediate grade.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.7
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• pp.4704-4710
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• 2015

The purpose of this study is to obtain a useful diagnostic image by increasing the signal strength of the peripheral artery, was to use a T1 shortening effect of gadolinium contrast agents to improve the disadvantages of the phase image. From october to december 2014 thirty patients were underwent the MRI scanning, except for heart disease. Research method was evaluated comparing the image after gadolinium contrast MR image acquisition step before evaluating the difference between the signal intensity for T1 shortening effect. In frontal lobe 19.45%, temporal lobe 23.09%, occipital lobe 25.45%, parietal lobe 18.82%, cerebellum 20.93% after peripheral arterial signal strength results of gadolinium contrast agent injection was increased significantly after injection of gadolinium both statistically significant. After injecting a contrast agent gadolinium in SWI by increasing the signal strength of the T1 shortening effect can be obtained when using the phase image to give a useful image in diagnosis and treatment.

• Korean Journal of Radiology
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• v.19 no.6
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• pp.1066-1076
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• 2018

Objective: The reliability of size measurements of liver metastases from neuroendocrine tumors (NETs) on contrast-enhanced computed tomography (CT) phases made by different readers may be hampered due to transient, variable rim enhancement in arterial phase (AP) or portal venous phase (PVP) images. We aimed to assess the reliability of tumor size measurements in pre- and post-contrast scans. Materials and Methods: The study coordinator selected target lesions according to Response Evaluation Criteria in Solid Tumors 1.1 guidelines in 44 consecutive patients with pathologically confirmed NET liver metastases. Two blinded readers measured the longest diameters of target lesions on pre-contrast, AP, and PVP images twice with a 4-week interval. Inter- and intra-observer agreements were evaluated using Bland-Altman plots and 95% limit of agreement (LOA) calculations. Results: Of the 79 target lesions (approximate mean size of 3 cm), 45 showed rim enhancement. Inter-observer agreement assessed based on LOA was highest in pre-contrast CT images (-6.1-5.7 mm), followed by PVP (-7.9-7.1 mm) and AP (-8.5-7.4 mm) images. Intra-observer agreement showed the same trend: -2.8-2.9 mm and -2.9-2.9 mm for readers 1 and 2, respectively, on pre-contrast CT, -2.8-2.9 mm and -3.0-3.2 mm, respectively, on PVP, and -3.2-4.2 mm and -3.4-3.2 mm, respectively, on AP images. Mean tumor diameters differed significantly among the phases in the following increasing order: pre-contrast CT, PVP, and AP images. Conclusion: There was better inter- and intra-observer agreement in size measurements of NET liver metastases on pre-contrast scans than on AP and PVP scans. Pre-contrast CT may be the optimal for measuring NET liver metastases if its accuracy is proven.