• Journal of Chest Surgery
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• v.37 no.9
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• pp.749-754
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• 2004

Off-pump coronary artery bypass grafting (Off-Pump CABG) has been proven to have less morbidity and to facilitate early recovery. High-risk surgical patients may have benefitted by avoiding the adverse effects of the cardiopulmonary bypass. We compared the effectiveness of Off-Pump CABG with that of coronary artery bypass using cardiopulmonary bypass (On-Pump CABG) in high-risk patients. Material and Method: 682 patients (424 Off-Pump CABG and 258 On-Pump CABG) underwent isolated coronary artery bypass grafting between January 2001 and June 2003. Patients who were considered high risk were selected High risk is defined as the presence of one or more of nine adverse prognostic factors. Data were collected from 492 patients in Off-Pump CABG and 100 in On-Pump CABG for risk factors, extent of coronary disease, and in-hospital outcomes. Result： Off-Pump CABG group and On-Pump CABG group did not show differences in their preoperative risk factors. We used more arterial grafts in Off-Pump CABG group (p < 0.05). Postoperative results showed that operative mortality (0.5% in Off-Pump CABG versus 2.0% in On-Pump CABG), renal failure (2.6% in Off-Pump CABG versus 7.0% in On-Pump CABG), and perioperative myocardial infarction (1.5% in Off-Pump CABG versus 1.0% in On-Pump CABG) did not differ significantly. However, Off-Pump CABG had shorter mean operation time (p<0.05), lower mean CK-MB level (p <0.05), lower rate of usage of inotropics (p < 0.05), shorter mean ventilation time (p <0.05), lower perioperative stroke (0% versus 2.0%), and shorter length of stay (p < 0.05) than On-Pump CABG. On-Pump CABG had more distal grafts (p<0.05) than Off-Pump CABG. Although Off-Pump CABG and On-Pump CABG did not show statistical differences in mortality and morbidity was more frequent in CABG. Conclusion: Off-Pump CABG reduces morbidity and favors hospital outcomes. Therefore, Off-Pump CABG is safe, reasonable and may be a preferable operative strategy for high-risk patients.

• Journal of the Mineralogical Society of Korea
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• v.20 no.3
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• pp.193-201
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• 2007

We used $^6Li$ and $^7Li$ MAS NMR to investigate the fate and local environments of Li in the interlayer of clay minerals such as hectorite, Woming-montmorillonite, beidellite, and lepidollite at room and high ($250^{\circ}C$) temperature. Although $^6Li$ NMR spectra show narrower peaks than those of $^7Li$ NMR, S/N ratio is low and there are no obvious differences in chemical shifts suggesting that it is difficult to apply $^6Li$ NMR to have information on the local environments of Li in the clay interlayers. $^7Li$ NMR spectra, however, show changes in the peak width and quadrupole patterns providing information on the local environments of Li in the interlayer even though changes in the chemical shift are not observed. In montmorillonite, two different local environments of Li are observed; one has a narrow peak with typical quadrupole patterns whereas another has a broad peak without those of the patterns. Changes in the peak width is also observed from broad to narrow in the $^7Li$ NMR spectra for beidellite but not for hectorite at high temperature. Our results suggest that the peak width change in the broad peak is attributed to the coordination changes in the water molecules around Li which is tightly bonded on the basal oxygen of Si tetrahedra as inner-sphere complexes. The narrow peak in montmorillnoite can be assigned to the Li bended as outer-sphere complexes.

• Clinical and Experimental Pediatrics
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• v.45 no.9
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• pp.1134-1140
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• 2002

Purpose : Childhood accidents have been increasing recently. Accidents rank as the leading cause of childhood mortality and morbidity. We performed this study to evaluate the causes of childhood accidents. Methods : The authors analysed retrospectively the medical records of 6,410 cases of childhood accidental injuries who visited the emergency room of Asan Medical Center from January 1990 to December 1999. Results : The most common type of accidents was trauma which accounted for 5,038 cases of the total accidents, followed by falls, burns, foreign body aspiration, and poisoning. The most common age of foreign body aspiration was under two years old and the male to female ratio was 2 to 1. The most common site of foreign body aspiration was the esophagus and the stomach, followed by the respiratory tract. In airways, the right and left main bronchus were the most common site for foreign body aspiration and were accompanied by the highest mortality. The most common foreign body in the gastrointestinal tract and respiratory tract were coins and peanuts, respectively. Conclusion : The most common cause of accidents was trauma, followed by falls, burns, foreign body aspiration, and poisoning. The incidence of foreign body aspiration and poisoning is increasing in infants. In cases of foreign bodies in airways, proper management is needed because of the high mortality rate.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.517-528
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• 2007

Domestic or international existing researches regarding rail damage factors are focused on laying, vehicle conditions, driving speed and driving habits and overlook characteristics of track structure (elasticity, maintenance etc). Also in ballast track, as there is no special lateral spring stiffness of track also called as ballast lateral resistance in concrete track, generally, existing study shows concrete track has 2 time shorter life cycle for rail replacement than ballast track due to abrasion. As a result of domestic concrete track design and operation performance review, concrete track elasticity is lower than track elasticity of ballast track resulting higher damage on rail and tracks. Generally, concrete track has advantage in track elasticity adjustment than ballast track and in case of Europe, in concrete track design, it is recommended to have same or higher performance range of vertical elastic stiffness of ballast track but domestically or internationally review on lateral spring stiffness of track is very minimal. Therefore, through analysis of service line track on site measurement and analysis on performance of maintenance, in this research, dynamic characteristic behaviors of commonly used ballast and concrete track are studied to infer elasticity of service line track and experimentally prove effects of track lateral spring stiffness that influence curved rail damage as well as correlation between track elasticity by track system and rail damage to propose importance of appropriate elastic stiffness level for concrete and ballast track.

• Journal of Bio-Environment Control
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• v.26 no.2
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• pp.100-107
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• 2017

This experiment was carried out to analyze the effects of substrate reuse on the growth and yield of summer paprika in cyclic hydroponics. The test group was divided into a new coco slab, one year reused coco slab two year reused coco slab based on 30% nutrient solution reuse, and was performed from April 18 to November 31, 2016 for 30 weeks. As a result, plant height of early growth was that the 2 year reused slab was longer than the new slab but the final growth period was 56.58 cm shorter. First group flower position was that reused slab was shorter by 2.92 cm than the new slab and the second group flower position was 0.31 cm long. The relative internode length of early growth, when the reused slab was used, the imbalance in the late growth stage was increased compared with the use of the new slab. The number of growth nodes in the 1 and 2 year reused slab was the smallest with 27.4 nodes. However, the number of harvested nodes did not show the difference in the test group, and the ratio of harvested that the 2 year reused slab was the highest at 26.8%. The ratio of unmarketable fruit tended to increase as the growth progressed. Fresh weight was 227.7g for new slab, 219.2g for 2 year reused slab and 21.2g for 1 year reused slab. The dry weight of the new slab increased with the reuse of the slab. It was 17.13g for new slab, 18.26g for 1 year reused, and 19.28g for 2 year reused. The average water content of the entire growth period was smaller as the slab was reused, and the 1 year reused slab was about 20g less than the 2 year reused slab. This trend was steadily occurring throughout the entire growing season. Especially, the reused slab for 1 year was less than 60g after 3 groups compared to other test groups. In conclusion, If will control seriously occurrence of unmarketable fruits by weakening after medium growth in summer-cultivated paprika in EC-based recycling hydroponic cultivation with reused cocopeat substrate, It is not what I have to worry that decrease of the yield and deterioration of the quality due to the change of physical and chemical properties of the slab and the pathogenic bacteria infection.

• Journal of Chest Surgery
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• v.29 no.6
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• pp.639-645
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• 1996

A 14-year-old male patient with previous surgical repair of tetralogy of Fallot was admitted with hemodynamically significant ventricular tachycardia (VT). On preoperative electrophysiologic study (EPS), the morphology of documented VT was RBBB of vertical axis with 320 msec cycle length. The endocardial mapping during VT delineated the origin of VT at right ventricular outflow tract (RVOT), where the patch was attached. The clinical VT had a clockwise reentry circuit around the patch with the earliest activation at the same site seen during the preoperative EPS. The previously placed right ventricular outflow patch and fibrous tissue were removed. During a postoperative EPS, it was no longer possible to induce the VT. Ventricular tachycardia following repair of tetralogy of Fallot seen in this patient was caused by a macro-reentry around the right ventricular outflow patch. We were able to ablate the VT with the aid of a detailed mapping of its epicardial activation sequence.

• The Korean Journal of Nuclear Medicine Technology
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• v.12 no.3
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• pp.229-234
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• 2008

Hepatobiliary scintigraphy is very sensitivity of hepatic cell and gallbladder, biliary track atresia and biliary leakage. however, Hepatobiliary scan of biliary leakage diagnosis was separated determine biliary leakage and bowl drainage bile-juice. The object of this study will determine biliary leakage and bowl drainage bile-juice to hepatobiliary scintigraphy both decubitus position in bile leakage patients. Material & Methode: 31 patients (meal 14, Femeal 17), $51.1{\pm}14.4$ years. dynamic scan acquisition 60 farme for 60 minute on supine position. and delay scan was 2 hrs, 4 hrs, 24 hrs for 5 minute on supine, both decubitus position. Both decubitus position scan was kept for 5 minutes. Efficient of Hepatobiliary Scintigraphy both decubitus position in bile leakage patients was compared leakage size, density, image of supine position and both decubitus position. Results: 23 patients for 31 bile leakage patients was checked up function image or delay image, and 8 patients was checked up bile leakage on both decubitus. anatomical leakage location was supine position very well, but both decubitus position was separated bile leakage and moving bile-juice in bowl. also, uptake (counts/pixel) average of roi and bkg was supine 5.02, left decubitus 2.08, right decubitus 2.68. No. pixels of supine ROI counted 1.91 times than left decubitus, 1.05 times than right decubitus. Conclusion: 31 patient both decubitus position, but decubitus position was separated bile juice movement in bowl leakage location. also, It was compared ROI/BKG ratio and ROI No. pixels of supine, both decubitus in 38.5% patients. And No. pixels of supine position was large 19%, 5% than left decubitus, right decubitus, And density was in low 60%, 50% than left decubitus, right decubitus. It was mean bile leakage of ROI. so, If Hepatobiliary Scintigraphy was additional both decubitus position scan in bile leakage patients, this study will be more valuable in diagnosis of bile leakage.

• Membrane Journal
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• v.6 no.3
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• pp.157-165
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• 1996

Polysulfone(PS) membranes were prepared from homogeneous PS solutions by the phase inversion technique. When propionic acid(PA) was added into a casting solution of n-methylpyrrolidone(NMP) and PS, precipitation rate of the solution film was accelerated. This kind of acceleration was consistent, even though a precipitating nonsolvent was changed from water to isopropanol. These phenomena were caused by decrease of nonsolvent tolerance in the casting solution due to addition of PA. PS powder was prepared by precipitation of a 3wt% solution in dimethylformamide(DMF) using ethanol as nonsolvent. Gas adsorption analysis of the powder showed that the capillary condensation sites were found in the powder structure. Membranes prepared from PS solution(15wt%) in NMP had the following characteristics of gas adsorption and water permeation. In gas adsorption analysis, the membrane precipitated using isopropanol showed low uptake of nitrogen gas and the capillary condensation sites were not found. On the contrary, a significant amount of the capillary condensation sites was found in the membrane coagulated by water, which was related to increase of nitrogen uptake. tn the membrane prepared froin the solution including PA, an increase of the Henry's law sites and the Langmuir sites was not found clearly. However, the capillary condensation sites were significantly increased, and the water transport also increased.

• Tuberculosis and Respiratory Diseases
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• v.47 no.3
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• pp.374-382
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• 1999

Background: The aim of this study was to investigate etiologic factor, treatment, prognosis of spontaneous pneumothorax (SP). Material and Methods: The medical records of 225 cases of SP experienced at Kyungpook University Hospital from Jan. 1996 to Dec. 1997 were retrospectively analyzed. Results: The patients were 128 primary SP and 97 secondary SP. The mean age was $30{\pm}15.5$ years in primary SP and $51{\pm}7.4$ years in secondary SP. The ratio of male to female was 8:1 in primary SP and 5.5:1 in secondary SP. Smoker was more common in seconday SP (71.1 %) than primary SP (34.4%). About 70% of patients with primary and secondary SP was underweighted. The previous history of SP was present in 28.9% and 25.8% of primary and secondary SP, respectively. The main underlying lung diseases in secondary SP were inactive tuberculosis (68%), active tuberculosis (12.4%) and COPD (11.3%). Tube thoracostomy was performed in 96.8% and 97.9% of primary and secondary SP, respectively. The duration of chest tube insertion was longer in seconday SP ($18.2{\pm}19.59$ days) than primary SP ($7.5{\pm}6.57$ days). The open thoracotomy were performed in 22.7% and 10.3% of primary and secondary SP, respectively. The most com- mon indication of open thoracotomy was recurrence in primary SP and persistent air leak in secondary SP. During following-up of $17{\pm}7.8$ months, the recurrence rate in patients with conservative treatment was 16.5% and 11.8% of primary and secondary SP, respectively. The recurrence was most common within 1 month after discharge. Conclusion: Greater attention and research about SP are necessary for more efficient patient care.

• Journal of Chest Surgery
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• v.35 no.6
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• pp.407-419
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• 2002

Atherosclerosis is a chronic inflammatory disease of the arterial wall characterized by progressive accumulation of lipids, cells, and extracellular matrix. Matrix metalloproteinases(MMPs) and tissue inhibitor of metalloproteinases(TIMPS) contribute to vascular matrix remodeling in atherosclerosis, and some cytokines may play role in the synthesis or activation of MMPs or TIMPs. Material and Method： We produced experimental atherosclerotic plaques in 9 rabbits by atherogenic hypercholesterol diet for 12 weeks, and 10 other rabbits were used as control group with standard laboratory chow, At that time, 19 rabbits were sacrificed and aorta, coronary arteries and blood specimens were prepared. The expressions of MMP-9, TIMP-2 and interleukin(IL)-18, and the bioactivity of IL-6 were investigated with H&E stain, immunohistochemical stain, immunoblotting(Western blot analysis), and bioassay. Result： Serum cholesterol in the experimental group increased up to 1258$\pm$262 mg/dL(control group： 41$\pm$7 mg/dL). All experimental group showed well-developed atherosclerotic plaques in aorta and coronary artery. The expression of MMP-9 in aorta and coronary artery of the experimental group showed significant increase than that of the control group by immunohistochemistry. Among the experimental group, complicated lesions with intimal rupture or complete luminal occlusion, demonstrated stronger expression of MMP-9. Interestingly, there was no difference in expression of TIMP-2 between the experimental and the control group. These findings were confirmed by Western blot analysis. The bioassay revealed significant up-regulation of serum bioactivity of IL-6 in the experimental group(4819.60$\pm$2021.25 IU/$m\ell$) compared to that of IL-6 in the control group(27.20 $\pm$ 12.19 IU/$m\ell$). IL-18 was expressed in all atherosclerotic plaques, whereas little or no expression was detected in the control group. Conclusion： The increased MMP-9 expression along with the unchanged TIMP-2 expression seem to be contributory factors in extracellular matrix degradation in atherosclerosis. Focal overexpression of MMP-9 may promote plaque destabilization and cause complications of atherosclerotic plaques such as thrombosis with/without acute coronary syndrome. Elevation of IL-6 and IL-18 may be more than just markers of atherosclerosis but actual participants in lesion development. Identification of critical regulatory pathway is important to improve the understanding of the cellular and molecular basis of atherosclerosis and may open the way for novel therapeutic strategies.