• Journal of Chest Surgery
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• v.39 no.7 s.264
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• pp.534-543
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• 2006

Background: There are a lot of debates regarding the optimal timing of operation of acute myocardial infarction (AMI). Off pump coronary artery bypass grafting (OPCAB) has benefits by avoiding the adverse effects of the cardio-pulmonary bypass, but its efficacy in AMI has not been confirmed yet. The purpose of this study is to evaluate retrospectively early and mid-term results of OPCAB in patients with AMI according to transmurality and timing of operation. Material and Method: Data were collected in 126 AMI patients who underwent OPCAB between January 2002 and July 2005, Mean age of patients were 61.2 years. Male was 92 (73.0%) and female was 34 (27.2%). 106 patients (85.7%) had 3 vessel coronary artery disease or left main disease. Urgent or emergent operations were performed in 25 patients (19.8%). 72 patients (57.1%) had non-transmural myocardial infarction (group 1) and 52 patients (42.9%) had transmural myocardial infarction (group 2). The incidence of cardiogenic shock and insertion of intra-aortic balloon pump (IABP) was higher in group 2. The time between occurrence of AMI and operation was divided in 4 subgroups (<1 day, $1{\sim}3\;days,\;4{\sim}7\;days$, >8 days). OPCAB was performed a mean of $5.3{\pm}7.1$ days after AMI in total, which was $4.2{\pm}5.9$ days in group 1, and $6,6{\pm}8.3$ days in group 2. Result: Mean distal an-astomoses were 3.21 and postoperative IABP was inserted in 3 patients. There was 1 perioperative death in group 1 due to low cardiac output syndrome, but no perioperative new MI occurred in this study. There was no difference in postoperative major complication between two groups and according to the timing of operation. Mean follow-up time was 21.3 months ($4{\sim}42$ months). The 42 months actuarial survival rate was $94.9{\pm}2.4%$, which was $91.4{\pm}4.7%$ in group 1 and $98.0{\pm}2.0%$ in group 2 (p=0.26). The 42 months freedom rate from cardiac death was $97.6{\pm}1.4%$ which was $97.0{\pm}2.0%$ in group 1 and $98.0{\pm}2.0%$ in group 2 (p=0.74). The 42 months freedom rate from cardiac event was $95.4{\pm}2.0%$ which was $94.8{\pm}2.9%$ in group 1 and $95.9{\pm}2.9%$ in group 2 (p=0.89). Conclusion: OPCAB in AMI not only reduces morbidity but also favors hospital outcomes irrespective of timing of operation. The transmurality of myocardial infarction did not affect the surgical and midterm outcomes of OPCAB. Therefore, there may be no need to delay the surgical off-pump revascularization of the patients with AMI if surgical revascularization is indicated.

• Radiation Oncology Journal
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• v.15 no.4
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• pp.393-402
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• 1997

Purpose : When an x-ray beam of small field size is irradiated to target area containing an air cavity, such as larynx, the underdosing effect is observed in the region near the interfaces of air and soft tissue. With a larynx model, air cavity embedded in tissue-equivalent material, this study is intonded for examining Parameters, such as beam quality, field size, and cavity size, to affect the dose distribution near the air cavity. Materials and Methods : Three x-rar beams, 4-, 6- and 10-MV, were employed to Perform a measurement using a 2cm $(width){\times}L$ (length in cm, one side of x-ray field used 2cm (height) air cavity in the simulated larynx. A thin window parallel-plate chamber connected to an electrometer was used for a dosimetry system. A ratio of the dose at various distances from the cavity-tissue interface to the dose at the same points in a homogeneous Phantom (ebservedlexpected ratio, O/E) normalized buildup curves, and ratio of distal surface dose to dose at the maximum buildup depth were examined for various field sizes. Measurement for cavity size effect was performed by varying the height (Z) of the air cavity with the width kept constant for several field sizes. Results : No underdosing effect for 4-MV beam for fields larger than $5cm\times5cm$ was found For both 6- and 10-MV beams, the underdosing portion of the larynx at the distal surface was seen to occur for small fields, $4cm\times4cm\;and\;5cm\times5cm$. The underdosed tissue was increased in its volume with beam energy even for similar surface doses. The relative distal surface dose to maximum dose was changed to 0.99 from 0.95, 0.92, and 0.91 for 4-, 6-, and 10-MV, respectively, with increasing field size, $4cm\times4cm\;to\;8cm\times8cm$, For 6- and 10-MV beams, the dose at the surface of the cavity is measured less than the predicted by about two and three percent. respectively. but decrease was found for 4-MV beam for $5cm\times5cm$ field. For the $4cm\timesL\timesZ$ (height in cm). varying depth from 0.0 to 4.8cm, cavity, O/E> 1.0 was observed regardless of the cavity size for any field larger than about $8cm\times8cm$. Conclusion : The magnitude of underdosing depends on beam energy, field size. and cavity size for the larynx model. Based on the result of the study. caution must be used when a small field of a high quality x-ray beam is irradiated to regions including air cavities. and especially the region where the tumor extends to the surface. Low quality beam. such as. 4-MV x-ray, and larger fields can be used preferably to reduce the risk of underdosing, local failure. In the case of high quality beams such as 6- and 10-MV x-rays, however. an additional boost field is recommended to add for the compensation of the underdosing region when a typically used treatment field. $8cm\times8cm$, is employed.

• Sijohaknonchong
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• v.24
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• pp.5-46
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• 2006

Korean verse has flexibly changed its form and contents according to the historical background of the times. This fact arouses reader sympathy because it has reflected ideas, historical aspects and realities of the times. However, korean verse has kept its own characteristics in some ways, allowing it to exist today. It holds its form as 3 verses of three by three or four meter and three letters of the last of three verses. It makes every different version which has specific aspects of each times in the same 'sijo' area. 'Sijo' in Korean poems, is the first form that has been changed from formal to private functionally. As a result of that common verses in the Goryeo to Joseon eras were going with the stream of the times. Verse was the plate for justice so that there was no double meaning, symbols, or technical sentences. It had to show the idea of Myungchundo Jwonginryun. The theme was commonly fitted within certain areas. such as blessings, fidelity, devotion, etc. Around the end of the Joseon era, there was activation of private verses - a form of sijo with no restrictions on the length of the first two verses. Some ideas had been changed because Sarimpa gained power, domestic conflict, and the introduction of practical science. These things had an effect on the form of Sijo. After all, it shows the ideas of collapsing feudalism, resistance of confucian ideas, equality of the sexes, and opposition to the group who rule the government. Thus Sasul Sijo seems to have the tendency of resistance to reality. It was a specialty of realism poetry It explained our life in detail and reflected real life by being an intermediary of realism. This met and represented the demand of a reader's expectations. After 1905, there was new form of sijo that is very different, in form and content, from the previous versions. It was even different in areas of what people accepted. They started to think sijo was not the form of lyrical verse that is once was. It became a 'record of reading'. The form changed to 'hung or huhung' that satirized the times and the ending of a word in the last verse. Although this form could deliver the tension in statement, it was too iu from the original form. Therefore, it didn't last long, and its position got smaller because of the free verse that had western influence and was emerging in the times. In the middle of 1920, there was a movement of Sijo revival. It was lead by Choinamsun. He wrote poems and Sijo which were effected by western ideas in his early works. Although he worked with that, he took the lead in the movement of Sijo revival. He published the collection of Sijo $\ulcorner$Baekpalbunnwoi$\lrcorner$ that has one major theme-patriotic sentiment. He thought an ancient poem was a part of racial characteristics so that he expressed the main theme which represented the times and situations of his era. Modern Sijo is difficult. Sijo has to have modern and Korean verse characteristics at the same time. If it considers a modern aspect too much, it could not be distinguished from sijo and free verse. If it overly leans toward Sijo. it would seem to be too conservative which it then could be said to have no real charm of a poem. In spite of these problems, it is written constantly, because it has its own specialty. It has been focused on some works because they reflect awareness of modern times, the democratic idea, and realism. Overall, the authors of Modern Sijo express various themes by using different forms. The more what we can guess in this work, Sijo will exist permanently because of its flexibility. Furthermore, one special characteristic-flexibility of the korean verse will make it last forever and it will be a genre in Korean poetry.