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The Prognostic Significance of the Number of Resected Lymph Nodes in Gastric Cancer Patients (근치 절제술을 시행한 위암에서 절제림프절 수의 임상적 의의)

  • Kim, Se-Jin;Jang, You-Jin;Kim, Jong-Han;Park, Sung-Soo;Park, Seong-Heum;Kim, Seung-Ju;Mok, Young-Jae;Kim, Chong-Suk;Ahn, Hyong-Gin
    • Journal of Gastric Cancer
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    • v.9 no.4
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    • pp.246-255
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    • 2009
  • Purpose: The objectives of this study were to investigate the impact of the number of resected lymph nodes on the survival of gastric cancer patients who underwent curative resection, and to evaluate the cut-off values that can have an influence on survival on the tumor stage-stratified analysis. Materials and Methods: The subjects were 949 gastric cancer patients who underwent curative resection at Korea University Medical Center from 1992 to 2002. They were classified according to the depth of tumor invasion, and the influence of the number of resected lymph nodes on survival was investigated. The cut-off value for the number of resected lymph nodes was determined as the smallest value that showed a significant survival difference. Results: The tumor size, location, lymph node stage, the number of metastatic lymph nodes and the number of resected lymph nodes were significantly different according to the tumor stage. The average number of resected lymph nodes was about 39, and it showed linear correlation with the number of metastatic lymph nodes. On the Cox proportional hazard model, the cut-off values of the number of resected lymph nodes, as corrected by the number of metastatic lymph nodes, was 14 for all the patients, 15 for the pT1 patients, 28 for the pT2 patients and 37 for the pT3 patients, respectively. Conclusion: Retrieving a number of lymph nodes that is more than the cut-off value could improve the survival of gastric cancer patients. Surgeons should also make efforts to perform an exact and thorough D2 lymph node dissection. Therefore, we urge surgeons to perform D2 dissection and pathologists should examine an certain exact number of lymph nodes.

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Growth Inhibitory Effect of Kimchi Prepared with Four Year-Old Solar Salt and Topan Solar Salt on Cancer Cells (토판염 및 4년 숙성 천일염으로 제조한 김치의 암세포 성장 억제 효과)

  • Yoon, Hae-Hoon;Chang, Hae-Choon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.7
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    • pp.935-941
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    • 2011
  • The growth inhibitory effects of kimchi prepared with solar salt were investigated. Chinese cabbages were brined with purified salt, four year-old solar salt, and Topan solar salt, and then mixed with other ingredients. The final salt concentration was adjusted to 2.2~2.4% (w/v) for each salt, and the kimchi was fermented at $7^{\circ}C$. When the acidity reached around 0.5~0.6%, the kimchi was used as a sample for further experimentation. MTT assay was used to measure the growth inhibitory effect of kimchi extracts (water, methanol) on BJ human foreskin normal cells, AGS human gastric adenocarcinoma cells, and HT-29 human colon carcinoma cells. Water extracts of all the kimchi samples showed growth inhibitory effects on cancer cells; however, there was no significant difference among the used salts. Methanol extracts of all the kimchi samples showed higher growth inhibitory effects compared to the water extracts. The methanol extracts of four year-old solar salt kimchi (AGS: 73%, HT-29: 48%) and Topan solar salt kimchi (AGS: 62%, HT-29: 46%) showed higher growth inhibitory effects than that of purified salt kimchi (AGS: 52%, HT-29: 39%). In addition, morphological changes of cancer cells (AGS, HT-29) and decreased cell numbers were observed when methanol extract of four year-old solar salt kimchi was treated to AGS and HT-29 cells. However, none of the kimchi extracts showed any growth inhibitory effect on BJ normal cells.

Effects of Temperature and Food on the Nymphal Development and Adult Longevity of the Green Mirid Bug, Cyrtorhinus lividipennis Router (Hemiptera: Miridae) and Its Egg Predation (온도 및 먹이가 등검은황록장님노린재의 약충발육과 성충수명 및 난 포식량에 미치는 영향)

  • 배순도;배태웅;조현제
    • Korean journal of applied entomology
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    • v.41 no.2
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    • pp.91-97
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    • 2002
  • This study was conducted to determine the effects of temperature and food onthe nymphal development and adult longevity of the green virid bug, Cyrtorhinus lividipennis Router. Nymphal period was 13.2 to 13.7 days at 24$^{\circ}C$, 10.4 to 10.9 days at 28$^{\circ}C$, and 9.0 to 9.3 days at 32$^{\circ}C$. Number of eggs predated by nymph was 10.6-14.3 at 24$^{\circ}C$, 7.5-9.2 at 28$^{\circ}C$, and 5.8-7.5 at 32$^{\circ}C$. Amount of predation was highest on BPH, followed by SBPH, WBPH, and GLH. Number of nympal moulting was mostly four times (55-75%) followed by three times (25-45%), regardless of temperature and food. Percent emergence rate was 52-70%, 48-66% and 22-38% at 24$^{\circ}C$, 28$^{\circ}C$ and 32$^{\circ}C$, respectively, showing a tendency to decrease with increasing temperature, and was affected by foods. Adult longevity, when supplied with one food, was 19.8 to 22.5 days at 24$^{\circ}C$, 15.6 to 17.0 days at 28$^{\circ}C$, and 10.3 to 11.7 days at 32$^{\circ}C$. There was no significant difference among foods in terms of adult longevity, but it tended to be slightly longer when provided with four foods than with one food. Number of eggs predated by an adult, when supplied with one food, was 35.7-54.2, 31.6-44.6 and 18.1-28.2 at 24$^{\circ}C$, 28$^{\circ}C$ and 32$^{\circ}C$, respectively. It was highest on BPH, followed by SBPH, WBPH and GLH regardless of temperature. Number of egg Predated by an adult, when supplied with four foods, was 4.0-28.9, 2.9-29.0 and 17-13.6 at 24$^{\circ}C$, 28$^{\circ}C$ and 32$^{\circ}C$, respectively, and was significantly different among foods supplied. The results suggest that the significantly different predation amount by adult was due to food preference amoung the different foods.

Retentive bond strength of fiber-reinforced composite posts cemented with different surface treatments (Fiber reinforced composite post의 표면 처리에 따른 접착 강도)

  • Roh, Hyunsik;Noh, Kwantae;Woo, Yi-Hyung;Pae, Ahran
    • The Journal of Korean Academy of Prosthodontics
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    • v.52 no.2
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    • pp.113-120
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    • 2014
  • This study will evaluate the effectiveness of various pretreatments when fiber-reinforced composite (FRC) post is bonded to endodontically treated tooth with resin cement. Materials and methods: Canal shaping of FRC post (DT Light post, Size 3, Bisco Inc., Schaumburg, IL, USA) was performed on endodontically treated premolars at 1.5 cm from CEJ. Samples were divided into 6 groups of surface treatment after conventional washing and drying to the canal. Total of 24 FRC posts were randomly divided into 6 groups of surface treatment as follows: Group C: control - no surface treatment, Group A: airborne-particle abrasion (Cojet sand, 3M ESPE), Group S: silanization (Bis-silane, Bisco Inc.), Group M: universal primer (Monobond-plus primer, Ivoclar Vivadent Inc.), Group AS: silanization after airborne-particle abrasion, Group AM: universal primer treatment after airborne-particle abrasion. Pretreated fiber posts were cemented with resin-based luting material and photo-polymerized and cut to the thickness of 1 mm. Push-out test using a universal testing machine was performed. Bonding failure strength of post dislodgement was measured and the type of bonding failure was classified. Data were analyzed with Kruskal-Wallis test and multiple comparison groups were performed using Tukey HSD value of rank test (${\alpha}=0.05$). Results: Group AS showed significantly highest bonding strength. Group S, group AM, group A, and group M showed lower bonding strength in order. The control group showed the lowest bonding strength. Conclusion: Surface treatment with silane showed to be the most effective of the surface pretreatment methods for cementation of FRC post. Surface treatment with universal primer showed no significant difference compared with no surface treatment group as for bonding strength.

THE COMPARISON OF STREPTOCOCCUS MUTANS ISOLATED FROM OCCLUSAL SURFACES OF CARIES AND NON-CARIES TEETH (우식치아와 정상치아의 교합면에서 분리한 Streptococcus mutans의 비교)

  • Park, Ho-Won;Jung, Tae-Sung;Jung, Jin;Kim, Shin
    • Journal of the korean academy of Pediatric Dentistry
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    • v.28 no.1
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    • pp.129-141
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    • 2001
  • When oral microorganisms were sampled from occlusal surfaces of caries and non-caries teeth, $3.43\times10^5$ CFU and $3.47\times10^3$ CFU of bacteria were counted on MSB agar plates, respectively. All the 20 colonies isolated from a caries surface were Streptococcus mutans but, only two of 20 colonies were identified as Streptococcus mutans by API test. S. mutans SM1 from caries tooth and S. mutans SM2 from non-caries tooth showed the same results except for $\alpha-galactosidase$ activity on sugar fermentation tests and biochemical tests. For the bacterial replication, both SM1 and SM2 were actively multiplicated at pH 5.5. And the viability of SM1 was high at 20% of sucrose, while that of SM2 was high at 5% of sucrose in the media. SM1 actively replicated at 16mM of $CaCl_2$, 160mM of KCl, and 6.4mM of $MgCl_2$, and the replication of SM2 was increased at 16mM of $CaCl_2$, 40mM of KCl, 6.4mM of $MgCl_2$. At 1mM of sodium bicarbonate and sodium phosphate, both bacteria were actively multiplicated. SM1 and SM2 were actively replicated at 1mM and 10mM of Tris, respectively. For potassium phosphate buffer, SM1 grew well proportionally to the concentration up to 100mM, while the growth of SM2 were inhibited by the increase of concentration. The 4.6 kb of gtf gene was amplified with a pair of primer, gtfB-F961 and gtfC-R5574 by polymerase chain reaction from the chromosomal DNA of SM1 and SM2. When 4.6kb bands were eluted from gel and were treated with restriction enzyme, EcoR I produced the same RFLP like 0.8kb and 3.8kb of DNA fragments for S. mutans GS-5, SM1 and SM2. By Hind III, the PCR products weren't digested for S. mutans GS-5 and SM1, but 3 fragments such as 2.4kb, 1.8kb and 400bp were examined for SM2. These results indicated the difference between gtf genes of SM1 and SM2. BamH I treatment showed 4 fragments for SM1 and SM2, while the 3 fragments for S. mutans GS-5. The PCR products were not digested by Kpn I, Sma I, Xho I and Pst I.

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Major Characteristics Related on Eating Quality and Classification of Inbred Lines of Waxy Corn (찰옥수수 자식계통 식미관련 특성 및 계통 분류)

  • Jung Tae-Wook;Kim Sun-Lim;Moon Hyeon-Gui;Son Beom-Young;Kim Si Ju;Kim Soon Kwon
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.50 no.spc1
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    • pp.161-166
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    • 2005
  • Objectives of this study were to select inbred lines which have a good eating quality and desirable segregates during inbreeding of waxy corn. The 64 inbred lines showed a large variance in their kernel shape and weight. 100-kernel weight, pericarp thickness, kernel length, kernel width, and kernel thickness ranged $11.7\~37.3g,\;11\~77{\mu}m,\;5.8\~9.6mm,\;6.5\~10.0mm$, and $4.1\~6.8mm$, respectively. The physicochemical analysis of 64 waxy corn inbred lines showed crude protein, crude fat, free sugar, and amylopectin content ranging $8.7\~15.8\%,\;2.3\~5.8\%,\;1.1\~11.0\%,\;and\;78.5\~93.8\%$, respectively. The texture property analysis of 64 inbred lines by texture analyzer showed a big difference. Gumminess, hardness, and chewiness of 64 inbred lines ranged $91\~383,\;181\~394,\;and\;73\~370$, respectively. The principal component analysis for 14 characteristics related to kernel quality showed that $73.1\%$ of the total variation could be attributed to the first five principal components. Biological meaning of the principal component was explained clearly by the correlation coefficient between principal components and characters. The first principal component appeared to correspond to small kernel and bad eating quality, The second principal component appeared to correspond to large kernel and good eating quality. The 64 inbred lines were classified into 8 groups by the cluster analysis using the first and second principal component. Among the groups, group VII and VIII included inbred lines with good eating quality that had thin pericarp thickness, low protein content, large kernel, and soft tenderness.

Effect of Water Temperature on Ammonia Excretion of Juvenile Pacific Cod Gadus macrocephalus (대구 Gadus macrocephalus 치어의 암모니아 배설에 미치는 수온의 영향)

  • Oh, Sung-Yong;Park, Heung-Sik;Noh, Choong-Hwan
    • Korean Journal of Ichthyology
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    • v.22 no.3
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    • pp.147-153
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    • 2010
  • A study was carried out to examine the effect of water temperature on daily pattern and rate of total ammonia nitrogen (TAN) excretion in juvenile Pacific cod Gadus macrocephalus (mean body weight: $36.5{\pm}0.8\;g$) under fasting and feeding conditions. Fish were acclimated over 10 days under three different water temperatures (9, 11 and $13^{\circ}C$), and transferred to TAN measuring system under each water-temperature condition. After 72 hours of starving, fasting TAN excretion was measured at each temperature. To investigate post-prandial TAN excretion, fish were hand-fed with a commercial diet containing 40.6% crude protein for 7 days, two times daily at 08:00 and 16:00 h. Water was sampled from both the inlet and outlet of the fish chamber every 2 h over a 24-h period. Both fasting and post-prandial TAN excretion increased with increased water temperatures (p<0.05). Mean fasting TAN excretion rates at 9, 11 and $13^{\circ}C$ were 9.3, 11.0 and $11.9\;mg\;TAN\;kg\;fish^{-1}\;h^{-1}$, respectively. The value of $9^{\circ}C$ was lower than those of 11 and $13^{\circ}C$ (p<0.05), but there was no significant difference between $11^{\circ}C$ and $13^{\circ}C$. Mean post-prandial TAN excretion rates at 9, 11 and $13^{\circ}C$ were 23.0, 31.6 and $45.4\;mg\;TAN\;kg\;fish^{-1}\;h^{-1}$, respectively. A peak value of post-prandial TAN excretion rate occurred after 2 h from each feeding, and the second value is always higher than the first value. Maximum post-prandial TAN excretion rate occurred after 10 h from the first feeding at $9^{\circ}C$ (mean $38.0\;mg\;TAN\;kg\;fish^{-1}\;h^{-1}$), $11^{\circ}C$ ($52.9\;mg\;TAN\;kg\;fish^{-1}\;h^{-1}$) and $13^{\circ}C$ ($77.5\;mg\;TAN\;kg\;fish^{-1}\;h^{-1}$), respectively. The TAN loss for ingested nitrogen at $9^{\circ}C$ (43.9%) was lower than those of $11^{\circ}C$ (46.4%) and $13^{\circ}C$ (48.4%). The overall results indicate that water temperature exhibits a significant effect on the nitrogen excretion of juvenile Pacific cod.

Investigation of the Distance from One Tooth Center to Adjacent Tooth Center and Dental Arch Size to Develope New Removable Die System for Fabrication of Dental Prosthetic Appliance (치과보철물 제조용 모형 조립체(가철식 치형 시스템) 개발을 위한 인접 치아 중심 간격 및 악궁 크기 조사)

  • Kim, Bu-Sob;Ma, Seung-Ho;Jeong, Kyung-Mok;Byun, Tae-Hee
    • Journal of Technologic Dentistry
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    • v.29 no.2
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    • pp.151-161
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    • 2007
  • To obtain the information of dental arch size and the distance from one tooth center to adjacent tooth center of occlusal surface of each tooth which is perforated by Pindex system on working cast for removable die system, 600 dental casts in Busan were examined. The distance of center of occlusal surface of each tooth and dental arch size were digitized. The results were as follows; 1. Mean values of the distance from center of maxillary central incisor to maxillary lateral incisor(tooth number 11$\sim$12, 21$\sim$22) is 5,7 mm, 12$\sim$13(22$\sim$23) is 5.9 mm, 13$\sim$14(23$\sim$24) is 6.9 mm, 14$\sim$15(24$\sim$25) is 7.1 mm, 15$\sim$16(25$\sim$26) is 8.4 mm, 16$\sim$17(26$\sim$27) is 10.2 mm, 11$\sim$21 is 7.30 mm. Mean values of the distance from center of mandibular central incisor to mandibular lateral incisor(tooth number 31$\sim$32, 41$\sim$42) is 4.5 mm, 32$\sim$33(42$\sim$43) is 4.8 mm, 33$\sim$34(43$\sim$44) is 6.3 mm, 34$\sim$35(44$\sim$45) is 7.2 mm, 35$\sim$36(45$\sim$46) is 9.2 mm, 36$\sim$37(46$\sim$47) is 10.7 mm, 31$\sim$41 is 4.7 mm. 2. Mean values of the distance from the center of maxillary right central incisor to the center of maxillary left central incisor(11$\sim$21) is 7.3 mm, 12$\sim$22 is 18.2 mm, 13$\sim$23 is 26.9 mm, 14$\sim$24 is 37.2 mm, 15$\sim$25 is 43.2 mm, 16$\sim$26 is 48.5 mm, 17$\sim$27 is 53.5 mm. Mean values of the distance from the center of mandibular right central incisor to the center of mandibular left central incisor(31$\sim$41) is 4.7 mm, 32$\sim$42 is 13.3 mm, 33$\sim$43 is 21.7 mm, 34$\sim$44 is 31.9 mm, 35$\sim$45 is 38.2 mm, 36$\sim$46 is 44.8 mm, 37$\sim$47 is 50.7 mm. 3. Mean values of the distance from the line of between 11$\sim$21 to 12$\sim$22 is 10.9 mm, 12$\sim$22 to 13$\sim$23 is 8.7 mm, 13$\sim$23 to 14$\sim$24 is 10.3 mm, 14$\sim$24 to 15$\sim$25 is 6.0 mm, 15$\sim$25 to 16$\sim$26 is 5.3 mm, 16$\sim$26 to 17$\sim$27 is 5.0 mm. 31$\sim$41 to 32$\sim$42 is 8.6 mm, 32$\sim$42 to 33$\sim$43 is 8.4 mm, 33$\sim$43 to 34$\sim$44 is 10.2 mm, 34$\sim$44 to 35$\sim$45 is 6.3 mm, 35$\sim$45 to 36$\sim$46 is 6.6 mm, 36$\sim$46 to 37$\sim$47 is 5.9 mm. 4. We checked the bottom side of cast to verify the position of dowel pin. There is no difference upper side and lower side.

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Image analysis of Specialized Vocational high school recognized by middle school student (중학생이 인식하는 특성화 고등학교 이미지 분석)

  • Kim, Yeong-Hun;Kim, Tae-Hoon
    • 대한공업교육학회지
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    • v.38 no.2
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    • pp.114-135
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    • 2013
  • The purpose of this study is to provide base line data for right concept and identity establishment of Specialized Vocational high school, to identify recognition of Specialized Vocational high school, to analyze image of Specialized Vocational high school recognized by middle school student. The population was all middle school third year students in Korea. Using random sampling technique, 50 classes of 61 schools were sampled for the study. A survey questionnaire used Semantic Differential(SD) suggested by Osgood(1957). SD consisted of a number of adjective pairs, finally, this study used 11 adjective pairs to have validity. 1,198 out of 1,441 questionnaire were returned (a return rate of 83.14%), among which 935 were used for the analysis after data cleaning. An alpha level of 0.05 was established a prior for determining significance. All data analysis was accomplished using the SPSS 20.0 Win. Based on the finding of the study, the major results of the this study were as follows : 1. Higher average is female students' image of Specialized Vocational high school than male students' that, but, The difference between the two samples was not statistically significant. 2. It was only 20% that receive career education of Vocational high school. It is necessary to accomplish and expand career education of Specialized Vocational high school for proper career education from middle school, to realize career exploration and decide one's career path based on one's specialty. 3. They have positive images who hope for going on to the Specialized Vocational high school of education than the others. 4. It is necessary to accomplish and expand career education of Specialized Vocational high school for proper career education from middle school, to realize career exploration and decide one's career path based on one's specialty, because the result was statistically significant. 5. They have the more possitive image of Specialized Vocational high school, the more know it, totally.

Analysis of Gel Powders Created from Different Acorn Crude Starches to Determine Country of Origin (도토리 조전분 및 겔 파우더에 대한 수입 원산지별 전자코 분석)

  • Yang, Kee-Heun;Lee, Kun-Jong;Kim, Mee-Ree
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.6
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    • pp.816-822
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    • 2012
  • Volatile components of acorn crude starches and gel powder created from them were analyzed by Gas Chromatograph-Ion Mobility Mass Spectrometry (GC-IMS). Crude starches were obtained from acorns harvested in South Korea (KAS), China (CAS), and North Korea (NAS). The principal component analysis (PCA) of each volatile component exhibited a significant contribution of PC 1 showing up to 60.5%. The acorn crude starch from KAS could be distinguished from crude starch from China by PC 1 (p<0.05). However, NAS and CAS could not be segregated statistically by the PC 1 component. PC 2, which exhibited 22.8% contribution, of KAS, also showed a meaningful difference (p<0.05) from those of CAS and NAS, making it possible to distinguish domestic acorn starch from imports.