• Korean Journal of Breeding Science
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• v.51 no.3
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• pp.263-276
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• 2019

'Sinjinbaek' is a bacterial blight (BB)-resistant, mid-late maturing rice cultivar with high grain quality. To diversify the resistance genes and enhance the resistance of Korean rice cultivars against BB, 'Sinjinbaek' was developed from a cross between 'Iksan493' (cultivar name 'Jinbaek') and the F₁ cross between 'Hopum' and 'HR24670-9-2-1' ('HR24670'). 'Jinbaek' is a BB-resistant cultivar with two BB resistance genes, Xa3 and xa5. 'Hopum' is a high grain quality cultivar with the Xa3 resistance gene. 'HR24670' is a near-isogenic line that carries the Xa21 gene, a resistance gene inherited from a wild rice species O. longistaminata, in the genetic background of japonica elite rice line 'Suweon345'. 'Sinjinbaek' was selected through the pedigree method, yield trials, and local adaptability tests. Using bioassay for BB races and DNA markers for resistance genes, three resistance genes, Xa3, xa5, and Xa21, were pyramided in the 'Sinjinbaek' cultivar. 'Sinjinbaek' exhibited high-level and broad-spectrum resistance against BB, including the K3a race, the most virulent race in Korea. 'Sinjinbaek' is a mid-late maturing rice cultivar tolerant to lodging. It has multiple disease resistance against BB, rice blast, and stripe virus. The yield of 'Sinjinbaek' was similar to that of 'Nampyeong'. 'Sinjinbaek' showed excellent grain appearance, good taste of cooked rice, and enhanced milling performance, and we concluded that it could contribute to improving the quality of BB-resistant cultivars. 'Sinjinbaek' was successfully introgressed with the Xa21 gene without the linkage drag negatively affecting its agronomic characteristics. 'Sinjinbaek' improved the resistance of Korean rice cultivars against BB by introgression of a new resistance gene, Xa21, as well as by pyramiding three resistance genes, Xa3, xa5, and Xa21. 'Sinjinbaek' would be suitable for the cultivation in BB-prone areas since it has been used in breeding programs for enhancing plants' resistance to BB (Registration No. 7273).

• Journal of Chest Surgery
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• v.41 no.6
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• pp.703-709
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• 2008

Background: Diagnosis and treatment are often successful in the setting of cardiac myxomas. However, cardiac myxomas can lead to catastrophic complications, due to intracardiac obstruction and embolism preoperatively, and can recur postoperatively. Material and Method: We retrospectively reviewed the clinical characteristics, surgical treatment, and recurrence data of 85 patients who underwent cardiac myxoma surgery at Asan Medical Center between November 1994 and June 2007. We analyzed the morphologic characteristics of 58 patients with left atrial myxomas and determined the development of functional mitral valve stenosis and systemic embolism through reviewing the results of preoperative echo-cardiograms to find potential preoperative risk factors. Result: Twenty-seven (31.8%) patients were men, and 58 (68.2%) were women. The mean patient age was $54.5{\pm}14.3$ years. Preoperative symptoms included obstructive symptoms in 41 (48.2%) patients, signs of embolism in 19 (22.4%), constitutional symptoms in 8 (9.4%), and no symptoms in 19 (20.0%). Among the 58 patients with left atrial myxomas, the mean maximal tumor diameter was $4.3{\pm}1.8$ (range $1.1{\sim}8\;cm$)cm. Twenty-six (44.8%) patients had a prolapsing type, defined as a tumor mobile enough to move down. to the mitral. annular plane during diastole, and 32 (55.2%) had villous type, defined as a tumor consisting of multiple fine villous extensions on the surface. Twelve (20.7%) patients had severe functional mitral valve stenosis, and 15 (25.9%) had systemic embolism preoperatively. The incidence of severe functional mitral valve stenosis was significantly higher in patients with the prolapsing type than in those with the non-prolapsing type (p=0.001). The mean maximal tumor diameter in patients with severe functional mitral valve stenosis was $5.1{\pm}1.0\;cm$, significantly larger than that seen in patients without severe functional mitral valve stenosis (p=0.041). The incidence of systemic embolism was significantly higher in patients with the villous type than in those with the smooth type (p=0.006). Postoperative complications were noted in 6 (7.1%) patients, and early mortality was noted in 1 (1.2%). The mean postoperative follow-up duration was $36.2{\pm}37.5$ months, with recurrence reported in 2(2.4%) patients during the follow-up period. The disease free interval were 48, 12 months, respectively. Conclusion: Surgical treatment for cardiac myxomas was performed safely, and long-term prognosis was good. In patients with left atrial myxoma, close attention should be maintained and surgery should be performed promptly in those of prolapsing type, those with large maximal diameter in order to prevent severe functional mitral valve stenosis, and those of villous type in order to prevent systemic embolism. Echocardiography should be followed serially in order to detect recurrence.