• Tuberculosis and Respiratory Diseases
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• v.77 no.4
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• pp.193-196
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• 2014

Acute airway obstruction after hemoptysis occurs due to the presence of blood clots. These conditions may result in lifethreatening ventilation impairment. We report a case of obstruction of the large airway by endobronchial blood clots which were removed using bronchoscopic cryotherapy at the bedside of intensive care unit. A 66-year-old female with endometrial cancer who had undergone chemotherapy, was admitted to the intensive care unit due to neutropenic fever. During mechanical ventilation, the minute ventilation dropped to inadequately low levels and chest radiography showed complete opacification of the left hemithorax. Flexible bronchoscopy revealed large blood clots obstructing the proximal left main bronchus. After unsuccessful attempts to remove the clots with bronchial lavage and forceps extraction, blood clots were removed using bronchoscopic cryotherapy. This report shows that cryotherapy via flexible bronchoscopy at the bedside in the intensive of intensive care unit is a simple and effective alternative for the removal of endobronchial blood clots.

• The korean journal of orthodontics
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• v.25 no.5 s.52
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• pp.641-654
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• 1995

The purpose of this report is to present the cause and treatment of posterior open bite. Posterior open bite is the open bite limited to posterior teeth. These problem usually are attributed to a mechanical interference with the eruption process, either ankylosis or some soft tissue interference. But, in some patient, lateral open bite is due to a disturbance of the eruptive mechanism itself and other disease or side effect following other treatment. Distinguising cause of posterior open bite, lack of eruption due to some external interference with eruption or primary failure of eruption mechanism, is important clinically because this determines the prognosis for orthodontic treatments. The characteristics, differential diagnosis with posterior open bite due to other etiologies and the treatment of these problems are presented and discussed,.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.11
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• pp.904-911
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• 2007

A measurement technique fur void fraction has been proposed using a time-resolved two-phase PIV system and the bubble dynamics has been investigated in gas-liquid two-phase flows. For the three-dimensional evaluation of the bubble information, both the images from the front and side views are simultaneously recorded into a high speed CCD camera by reflecting the side view image on a $45^{\circ}$ oriented mirror to be juxtaposed with the front view image. Then, a stereo-matching technique is applied to calculate the void fraction, bubble size and shape. To obtain the rising bubble velocities, the 2-frame PTV method was adopted. The present technique is applied to freely rising bubby flows in stagnant liquid. The results show that the increase of bubble flow rate gives rise to the increase of bubble size and rising velocity at first. If it goes over a certain level, the rising velocity becomes constant and the horizontal velocity grows bigger instead due to the obstruction of other bubbles.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.5
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• pp.171-178
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• 2008

The combustion and exhaust emission characteristics were investigated in an DME fueled HCCI engine. Carbon dioxide, nitrogen and mixed gas, which was composed of carbon dioxide and nitrogen, were used as control parameters of combustion and exhaust emission. As the oxygen concentration in induction air, which was occurred by carbon dioxide, nitrogen and mixed gas, was reduced, the start of auto-ignition was retarded and the burn duration was extended due to obstruction of combustion and reduction of combustion temperature. Due to these fact, indicated mean effective pressure was increased and indicated combustion efficiency was decreased by carbon dioxide, nitrogen and mixed gas. In case of exhaust emission, hydrocarbon and carbon monoxide was increased by reduction of oxygen concentration in induction air. Especially, partial burning was appeared at lower than about 18% of oxygen concentration by supplying carbon dioxide. However it was overcome by intake air heating.

• Proceedings of the KOSOMBE Conference
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• v.1996 no.11
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• pp.7-10
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• 1996

The purpose of this experimental investigation is to examine the influence of the catheter on local pressure changes and flow rate in an arterial branch model similar to the femoral artery of man. Effects of branch to main lumen flow rate ratios and the locations of catheter tip were found to be significant on the local pressure changes. Relatively large pressure drops due to obstruction effects may induce endothelial cell damage, which have been reported to be the primary cause of the initiation of the atherosclerosis.

• Korean Journal of Metals and Materials
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• v.46 no.7
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• pp.403-411
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• 2008

Zr-based amorphous alloy matrix composites reinforced with tantalum continuous fibers were fabricated by liquid pressing process, and their microstructures and mechanical properties were investigated. About 60 vol.% of tantalum fibers were homogeneously distributed inside the amorphous matrix, which contained a small amount of polygonal crystalline particles. The ductility of the tantalum-continuous-fiber-reinforced composite under tensile or compressive loading was dramatically improved over that of the monolithic amorphous alloy, while maintaining high strength. The consequential observation of the tensile deformation and fracture behavior of the composite showed the formation of multiple shear bands and multiple necking, crack deflection in the amorphous matrix, and obstruction of crack propagation by ductile fibers, thereby resulting in very high tensile elongation of 7.2%. These findings suggested that the liquid pressing process was useful for the development of amorphous matrix composites with improved ductility.

• Journal of Sensor Science and Technology
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• v.32 no.6
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• pp.418-424
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• 2023

Natural killer (NK) cells play a crucial role in combating infections and tumors. However, their therapeutic application in solid tumors is hindered by challenges, such as limited lifespan, tumor penetration, and delivery precision. Our research introduces a novel ultrasonic actuation technique to navigate NK cells more effectively in the vascular system, particularly at vessel bifurcations where targeted delivery is most problematic. We use a hemispherical ultrasonic transducer array that generates phase-modulated traveling waves, focusing on an ultrasound beam to steer NK cells using blood-flow dynamics and a focused acoustic field. This method enables the precise obstruction of non-target vessels and efficiently directs NK cells toward the tumor site. The simulation results offer insights into the behavior of NK cells under various conditions of cell size, radiation pressure, and fluid velocity, which inform the optimization of their trajectories and increase targeting efficiency. The experimental results demonstrate the feasibility of this ultrasonic approach for enhancing NK cell targeting, suggesting a potential leap forward in solid tumor immunotherapy. This study represents a significant step in NK cell therapeutic strategies, offering a viable solution to the existing limitations and promising enhancement of the efficacy of cancer treatments.

• BMB Reports
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• v.29 no.2
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• pp.142-145
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• 1996

To investigate the cause of increased plasma catecholamine levels in liver disease, catechol-O-methyltransferase (COMT), which provides a major route of catabolism for circulating catecholamines, was studied under the cholestasis induced by mechanical biliary obstruction in rats. Monoamine oxidase (MAO) activity and the $K_m$ and $V_{max}$ values for both enzymes were also measured. Cytosolic, microsomal, and mitochondrial COMT activities in the cholestatic liver were significantly decreased throughout the experiment. Microsomal, and mitochondrial MAO activity in the cholestatic liver were also significantly decreased. Vmax values of COMT and MAO were lower. Serum COMT and MAO activities were detected after CBD ligation. These results indicate that plasma catecholamine levels are increased in liver disease due to decreased hepatic degradation of catecholamines by decreased activities of COMT and MAO. The decreased activity of these enzymes is caused by decreased biosynthesis and by flowage into the blood from the damaged hepatocyte.

• Journal of Korean Neurosurgical Society
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• v.29 no.2
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• pp.270-273
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• 2000

Ventriculoperitoneal(V-P) shunt has been used as a popular method for surgical treatment of hydrocephalus. But complications such as infection, mechanical obstruction and failure of flow rate sometimes make painful stress to neurosurgeons and patients. Of particular, migration of distal V-P shunt catheter to extraperitoneal space has rarely been reported. Even rarer is intracardiac migration of distal V-P shunt catheter. Authors report a such case and discuss the possible mechanism and preventive method.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.3
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• pp.446-454
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• 2008

Control devices for fire safety systems located in a engine room are to be arranged at a safe position which is easily accessible during a fire. To develop an interpretation for the safe position in engine rooms, calculation and experiments are carried out to determine a correlation between radiant heat and distance from fire in this paper. On the basis of results of this research, the control devices for a main engine are to be installed in the behind side of an obstruction to reduce radiant heat from the fire of the main engine. In case of other control devices, they are also to be provided in the same manner of control devices for the main engine or are to be placed with 5 meters far from fire hazards.