• Journal of Chest Surgery
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• v.21 no.2
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• pp.246-253
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• 1988

An in vitro model providing with a recirculating perfusion apparatus using an isolated canine heart and its autogenous blood, which was prepared for study of myocardial protection method. This apparatus was easily used by quick connect system and maintained well heart function for about 2 hours. The Langendorff perfusion was initiated for a 10 minute period by introducing perfusate at 37` into the aorta from aortic reservoir located 100 cm above the heart. The isolated perfused working canine heart model was a left heart preparation in which oxygenated perfusion medium [at 37K] entered the cannulated left atrium at a constant flow rate [900ml/ min] under 20 mmHg overflow system and was spontaneously ejected[no electrical pacing] via an cannula against a hydrostatic pressure of 80 cm H2O. During this working period, various indices of cardiac function were measured. The cardiac functions were stable for over 2 hours with perfusion of Krebs-Henseleit solution and autologous blood[1:1] mixture in volume and maintained heart rate ]]3-122/bpm peak systolic pressure 109-113 mmHg, cardiac output 900 ml / min and left atrial mean pressure 8-9 mmHg. In this model, the efficiency of myocardia] protection could be easily measured by means of functional, enzymatic, biochemical and ultrastructural assessment. And also, we believe this model to be a useful assessment screening model of recovery state after long duration of myocardial preservation of donor heart without difficult transplantation procedures.

• Journal of the Korean Magnetics Society
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• v.27 no.4
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• pp.145-152
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• 2017

The arterial spin labeling (ASL) is a magnetic resonance imaging (MRI) method that can evaluate tissue perfusion using blood in the body. The characteristic of non-invasive examinations without contrast agents and the quantitative measurement of perfusion volume is possible, which are increasingly being used for clinical and research purposes. Up to the present, The ASL method has lower SNR than the perfusion imaging method using contrast agent and because optimization of various parameter in the imaging process is difficult, Which may result in measurement errors. To improve this, ASL methods using various technologies are introduced. This paper briefly introduces the outline of ASL, its features in imaging process, various techniques, and clinical application.

• Microbiology and Biotechnology Letters
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• v.18 no.1
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• pp.61-65
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• 1990

Lectin related inducer can enhance IgG$_1$ production rate from murine hybridoma cells by employing step-feeding of serum free media with producing about 40 mg/$\ell$ of monoclonal antibodies. This step-feeding perfusion process also proves to be able to cutivate animal cells when serum free media can not support the growth of these cells in perfusion process, as well as to improve production rate. This process yields about 28 x 10$^{-10}$ mg of MAb/cells/h compared to 11.1 x 10$^{-10}$ and 4.0 x 10$^{-11}$ mg/cells/h for perfusion process and batch cultivation with 10% serum containing media, respectively.

• Journal of Radiation Industry
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• v.10 no.4
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• pp.193-198
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• 2016

Perfusion magnetic resonance image of biological mechanism are independent of magnetic field strength in hyper acute ischemic stroke. 3.0 T magnetic field, however, does affect the SNRs (signal to noise ratio) and artifacts of PMRI (perfusion magnetic resonance image), which basically will influence the quantitative of PMRI. In this study, the effects of field strength on PMRI are analyzed. The effects of the diseases also are discussed. PMRI in WM(white matter), GM (gray matter), hyper acute ischemic stroke were companied with 1.5 T and 3.0 T on SNR. PMRI also was compared to the SI difference after setting ROI(region of interest) in left and right side of the brain. In conclusion, the SNRs and SI of the 3.0 T PMRI showed higher than those at 1.5 T. In summary, PMRI studies at 3.0 T is provided significantly improved perfusion evaluation when comparing with 1.5 T.

• Journal of Chest Surgery
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• v.23 no.5
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• pp.864-870
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• 1990

This study was undertaken to evaluate current technique of extracorporeal circulation by analyzing the results in 73 cases. We performed standard cardiopulmonary bypass using Polystan roller pump, bubble[Polystan] and membrane[Cobe] oxygenator. There were 42 males and 31 females. We studied the changes of hemoglobin. hemodynamics, speed of cooling and warming, methods of cannulation and ACT. Arterial cannula was inserted on ascending aorta except for 7 cases of femoral cannulation. Preoperative hemoglobin was 13.2 gm% and this value dropped to 7.5 gm% during perfusion. Blood pressure of 113 mmHg in systolic dropped 57mmHg in 10 minutes of perfusion and became 98 mmHg at the end of perfusion. Initial drop of blood pressure was marked in pediatric patient. Mean cooling time was 19.4 min[0.54 Q /min] and warming time was 34 minutes[0.25 Q /min]. During perfusion, ACT was maintained above 600 sec and 44 patient did not need additional Heparin.

• Korean Journal of Radiology
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• v.21 no.4
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• pp.462-470
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• 2020

Objective: To demonstrate that human visual illusion can contribute to sub-endocardial dark rim artifact in contrast-enhanced myocardial perfusion magnetic resonance images. Materials and Methods: Numerical phantoms were generated to simulate the first-passage of contrast agent in the heart, and rendered in conventional gray scale as well as in color scale with reduced luminance variation. Cardiac perfusion images were acquired from two healthy volunteers, and were displayed by the same gray and color scales used in the numerical study. Before and after k-space windowing, the left ventricle (LV)-myocardium boarders were analyzed visually and quantitatively through intensity profiles perpendicular the boarders. Results: k-space windowing yielded monotonically decreasing signal intensity near the LV-myocardium boarder in the phantom images, as confirmed by negative finite difference values near the board ranging -1.07 to -0.14. However, the dark band still appears, which is perceived by visual illusion. Dark rim is perceived in the in-vivo images after k-space windowing that removed the quantitative signal dip, suggesting that the perceived dark rim is a visual illusion. The perceived dark rim is stronger at peak LV enhancement than the peak myocardial enhancement, due to the larger intensity difference between LV and myocardium. In both numerical phantom and in-vivo images, the illusory dark band is not visible in the color map due to reduced luminance variation. Conclusion: Visual illusion is another potential cause of dark rim artifact in contrast-enhanced myocardial perfusion MRI as demonstrated by illusory rim perceived in the absence of quantitative intensity undershoot.

• Journal of Chest Surgery
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• v.55 no.4
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• pp.288-292
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• 2022

Ex vivo lung perfusion (EVLP) is a technique that enables active metabolism of the lung by creating an environment similar to that inside the body, even though the explanted lungs are outside the body. The EVLP system enables the use of lung grafts that do not satisfy the acceptance criteria for lung transplantation (LTx) by making it possible to evaluate the function of the lung grafts and repair lungs in poor condition, thereby reducing the waiting time of patients requiring LTx and consequently mortality.

• Journal of Chest Surgery
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• v.19 no.2
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• pp.209-216
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• 1986

The purpose of this study is to predict postoperative lung function by perfusion lung scanning method. 40 patients who underwent lobectomy or pneumonectomy between 1983-1985 were analyzed. Mean preoperative FEV1 was 2.36 L in lobectomy cases and 1.73 L in pneumonectomy cases. Preoperative and postoperative lung function were measured by routine spirometry in sitting position. Perfusion lung scanning was performed by 99mTc-MAA radioisotope. Postoperative FEV1 and VC were predicted by the formula; Postoperative FEV1 [VC]=Preoperative FEV1 [VC] x percent function of regions of lung not to be resected. In this study, I concluded that perfusion lung scanning is a simple and useful method to predict postoperative ventilatory function after pneumonectomy of lobectomy.

• Journal of Microbiology and Biotechnology
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• v.4 no.3
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• pp.200-203
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• 1994

Spodoptera frugiperda IPLB-SF-21-AE cells were cultivated in a spin-filter bioreactor with continuous perfusion for the recombinant $\beta$-galactosidase production. At the perfusion rate of 0.06 $hr^{-1}$, the maximum cell density of insect cells in this bioreactor system reached 3.5$\times$$l0^6$ viable cells/ml using the Grace media containing 5% FBS and 0.3% Pluronic F-68. The recombinant $\beta$-galactosidase production of 8, 100 units per reactor volume was also achieved at this perfusion rate.

• Journal of Chest Surgery
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• v.23 no.6
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• pp.1067-1073
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• 1990

To clarify the changes of left ventricular function under normothermia, the time interval between the onset of ischemia and the beginning of contracture of left ventricle[TIC] were recorded in newborn piglet. Myocardial performance was assessed using intraventricular balloon to determine compliance and systolic function after 5 to 10 minutes interval per-fusing normothermic substrate free Krebs solution as a perfusate. The time to onset TIC was 29.5\ulcorner1.7 minutes and peak ischemic contracture was 46.7\ulcorner4.0 minutes[p<0.01]. In myocardial performance, systolic function of left ventricle[defined as cardiac contractility] was kept until 25 minutes of perfusion, but was decreased abruptly after 30 minutes of perfusion[p<0.0018] and diastolic function of left ventricle[defined as diastolic compliance] was kept until 15 minutes of perfusion, but was decreased after 20 minutes of perfusion [p=0.00\ulcorner9]. This study demonstrated maximal time of the tolerance to normothermic global ischemia and functional changes of left ventricle using Krebs perfusate under the same condition.