• Title/Summary/Keyword: 전남대학교

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Acorn Production and Characteristics of Quercus acuta Thunb - Focused on Wando, Jindo and Haenam in Jeollanam-do, Korea - (붉가시나무의 종실 생산량 및 형질특성 - 전라남도 완도, 진도, 해남을 중심으로 -)

  • Kim, Sodam;Park, In-Hyeop
    • Korean Journal of Environment and Ecology
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    • v.35 no.6
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    • pp.621-631
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    • 2021
  • The purpose of this study is to survey and analyze acorn production and characteristics of the Quercus acuta Thunb. according to the need for information on seed supply and seedling cultivation during the restoration of warm broad-leaved forests. For the survey, a total of 30 seed traps with a surface area of 1 m2 were set up, 3 in each of 10 quadrats (8 in Wando, 1 in Haenam, and 1 in Jindo). The acorns that fell in the seed trap at the end of each month were collected from August to December each year between 2013 to 2016. The collected acorns were then classified into sound, damaged, decayed, or empty grade, and the number of acorns produced was calculated. In the case of sound acorns, acorn traits, such as length, diameter and weight of acorns without cupule, were measured. Duncan's multiple tests of acorn production and characteristics were conducted for comparative analysis of the annual average values with the values by year, stand, month, and treatment plot. The annual number of acorn dropped into the seed traps in each quadrat from 2013 to 2016 was 5-350 acorns/3 m2 in 2013, 17-551 acorns/3 m2 in 2014, 5-454 acorns/3 m2 in 2015, and 14-705 acorns/3 m2 in 2016. There was a large difference in acorn production between the quadrats, presumably attributed to the difference in the amount of light received due to the density of trees in the square. Annual acorn production per area was 335,000 acorns/ha in 2013, 932,000 acorns/ha in 2014, 556,000 acorns/ha in 2015, and 1,037,000 acorns/ha in 2016. That was a sharp variation of acorn production in the two-year cycle. As the fluctuation in the production of Q. acuta showed simultaneity between stands, it is judged that Quercus acuta Thunb. had a clear cycle of fruitfulness and fruitiness between forest objects. September showed the biggest amount of fallen acorns and largest damage from insect pests, indicating that preventing early fall of acorns could increase the fruiting period and enable mass production of sound acorns. There was no significant difference between annual average acorn length in each region. In the case of the acorn diameter and weight, the average values of acorns from Haenam were significantly higher than those from Wando and Jindo. There was no significant difference in the average annual acorn characteristics by month, and the average annual acorn length, diameter, and weight in November were 19.72mm, 12.23mm, and 1.64g, respectively, the highest between August and November.

The Growth of Ginseng Industry and the Activities of Ginseng Cultivators in the 1930s: Focusing on Non-Government-Contract Cultivation Areas (1930년대 인삼업의 성장과 삼포민의 활동 -특별경작구역 이외 지역을 중심으로-)

  • Jeongpil Yang
    • Journal of Ginseng Culture
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    • v.5
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    • pp.52-76
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    • 2023
  • This article focuses on changes in the ginseng industry in the 1930s in areas other than the Government Contract Cultivation (GCC) zones. A major characteristic of the ginseng industry in the 1930s was the rapid increase in the area covered by ginseng gardens: the area was about 212 ha in 1929 and 252 ha in 1930 and 1931 but soared to around 441 ha in 1938. This occurred because the non-GCC areas increased significantly during this period. Until the early 1930s, the ratio of GCC to non-GCC areas was 70:30. By the late 1930s, however, the ratio had changed to 53:47. The reason for this change was that the area of the newly established ginseng gardens in the GCC zones had decreased, while that of the non-GCC ginseng gardens had steadily increased. Due to the Japanese invasion of China, China boycotted red ginseng, and exports were sluggish, so the GCC areas were reduced. On the other hand, the non-GCC ginseng gardens were not affected, and the area they covered steadily increased. As a result, in the 1930s, the ginseng industry outside of the GCC areas grew rapidly. The region that led the growth of the ginseng industry outside of the GCC zone was Jeonbuk. By the late 1930s, Jeonbuk dominated the other provinces and accounted for more than 50% of the non-GCC farming zone. Gyeongbuk and Gangwon-do followed Jeonbuk in terms of ginseng cultivation areas. While Gyeonggi-do, Gyeongnam, and Chungbuk were also active in ginseng cultivation, Jeonnam and Chungnam were not active. In the 1930s, the growth of the ginseng industry outside of the GCC zones was driven by the efforts of ginseng farmers and the support of local governments. An examination of Yecheon-gun in Gyeongbuk, Ganghwa-gun in Gyeonggi, and Jecheon-gun in Chungcheongbuk-do showed that ginseng farmers organized cooperatives as the ginseng industry steadily developed in these regions, and these cooperatives worked systematically to cultivate and sell ginseng. In the case of Ganghwa-gun, activities were carried out to incorporate the GCC zone. The Deoksan Ginseng Association in Jecheon-gun determined that financing for cultivation was key and requested subsidies from the provincial government. Administrative authorities also supported the activities of the ginseng farmers. The activities of the farmers and the support of the administrative authorities together led to the growth of the ginseng industry during this period.

Analysis of Climate, Weather, Solar Radiation and Solar Energy in Major Cities of Tajikistan (타지키스탄 주요 도시의 기후, 날씨, 일사량 및 태양에너지 분석)

  • Taeyoo Na;Jeongdu Noh;Hyeontae Kim;Seong-Seung Kang
    • The Journal of Engineering Geology
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    • v.33 no.3
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    • pp.389-401
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    • 2023
  • Climate, weather, insolation (solar radiation), and solar energy in major cities of Tajikistan were investigated prior to construction of infrastructure for the Dushanbe Solar Station. In Dushanbe city there was a 70% probability of sunny days from May 16 to October 23, a period of 5.2 months. August had the most sunny days of in the year, with 99% probability of a sunny, the cloudiest month was February with a 41% chance of being sunny. In major cities of the Sughd and Gorno-Badakhshan states, the average number of cloudy days per month was ~3.3, with Dzhauz having 53 day and Fedchnko Glacier 79 days. For the 18 major cities of Tajikistan, the average annual total solar radiation was 2,429 W/m2, and the average monthly solar radiation was 202 W/m2. The city with the lowest annual total and monthly average solar radiation was Shartuz in Sughd state, with values ~2.7% less than the national average. The cities with the highest annual total and monthly average solar radiation were Khorog and Jirgatol in Gorno-Badakhshan state, with values ~10% above the national average. The daily average incident shortwave solar energy in the cities Dushanbe, Karakul, and Jirgatol was ~7.8 kWh per 2.4 m2 during summer (May-August), and 2.7 kWh during winter (November-February), or ~35% that of summer.

Yeomjae Song Tae-hoe Origin and art world of calligraphy and painting (염재(念齋) 송태회(宋太會) 서화의 연원과 예술세계)

  • Kim Doyoung
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.5
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    • pp.255-262
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    • 2023
  • In the early 20th century, Yeomjae Song Tae-hoe (念齋 宋泰會, 1872-1941), a disciple and onetime adopted son of teacher Song Su-myeon(宋修勉, 1847-1916), moved to Gochang and laid the foundation for Gochang calligraphy and painting, and it can be seen that a full-fledged flow began. Yeomjae Song Tae-hoe was a scholar and calligrapher of the late Joseon Dynasty and modern period from Hwasun, Jeollanam-do. He is a person who created the foundation of Gochang calligraphy and painting while working as an educator in Chinese literature, calligraphy, and painting, mainly in his hometown of Hwasun and Gochang, while engaging in creative activities. He was intelligent from a young age and showed an extraordinary talent for calligraphy. At the age of 16, he passed the Jinsa exam (童蒙進士) and became the youngest student to study at Sungkyunkwan. He was active by holding exhibitions nationwide based in Gochang and Jeonju, and was also an educator who fostered younger students by establishing Gochang High School (currently, Gochang Middle and High School) to cultivate national spirit and history. Yeomjae drew strong and healthy landscape paintings under the absolute influence of the painting style of Saho Song Su-myeon, and dealt with various materials of southern school literati paintings such as flowers and birds and four plants. In particular, he is a representative calligrapher who encompasses the early modern era and the modern era in that he expressed his interest in new cultural artifacts as well as the realization of a modern-oriented realistic landscape based on Korean natural beauty. He laid the foundation for modern and contemporary calligraphy and painting. Goam Lee Eung-no (顧菴 李應魯, 1904-1989), a world-renowned painter, learned the basics of ink painting from Yeomjae in his late teens.However, compared to his various artistic and social activities, it is regrettable that he is limited and evaluated as a local writer.

A Study on the Current Status and Location Characteristics of Stone Jangseung - Focusing on Doljangseung in Daejeon Area - (돌장승의 현황 및 입지특성에 관한 연구 - 대전지역 돌장승을 중심으로 -)

  • Lee, Dong-Hun;Heo, Sang-Hyun
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.42 no.1
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    • pp.1-13
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    • 2024
  • This study requires a strict distinction between the sculptures we call 'Jangseung' because their origins, history, or functions are different from each other. Therefore, a theoretical consideration was made through the origin and history of Jangseung. Currently, Jangseung is widely distributed throughout the country, but the Honam region shows the largest distribution, and 73 out of 167 locations nationwide remain in the Chungcheongnam-do region. Among these, there are 54 stone jangseungs in Jeollanam-do, 37 in Jeollabuk-do, and 19 in Jeollabuk-do. In particular, the original shape of the stone jangseungs in the Honam region is well preserved, and as a center of the agricultural economy, the jangseung culture is active in this region. It was popular, and many stone jangseungs were built in the Daejeon area amid social changes in the late Joseon Dynasty. However, in the South Chungcheong region, there is not much culture about stone jangseungs, but there is a village meaning and consciousness that stone jangseungs have, but it is true that research on stone jangseungs is insufficient in various aspects. Among them, the form of the stone jangseung built between the 17th and 19th centuries is a sculpture that contrasts with the wooden pillar-type jangseung that is common in the central region, and shows the simple mentality of the people of the Daejeon region without any embellishment. Through Jangseung, we were able to discover the unconscious and potential creativity of national aesthetic consciousness. Therefore, the purpose is to trace the change process of the stone jangseung in the Daejeon area, investigate the functional aspects of this structure, and based on this, examine the various current status and locational characteristics of the so-called stone jangseung. In addition, the wooden figures and stone statues that are now commonly known as Jangseung were each erected in different times and for different reasons. Centering around Daejeon, the study attempted to research and identify representative stone monuments or 'stone jangseungs' that appear as stone statues, and even suggest their form through locational characteristics and suggestions. As a result, traditional jangseungs have changed in various forms as times change, reaching their present form, and the religious elements of modern jangseungs made and erected today are weakened or disappeared, and are used as symbolic symbols or sculptures of tradition. Although it has lost its traditional function as an object of village faith, it functions as a milestone or sign at the entrance to a village or event site, or as an exhibition in special places. It was found that the modern jangseung is a representative symbol of Korean traditional culture and is being re-created as an artistic sculpture that expresses common, simple, natural beauty and humor. Therefore, through this study, based on more specific and systematic investigation and research on the jangseung, it was materialized into a more developed form considering its utilization plan to prevent miscellaneous spirits from entering the village through the currently existing stone jangseung and to improve the spatial space accordingly. It is believed that what is located at the entrance can greatly convey its meaning. Therefore, it is judged necessary to maintain the strong characteristics of folk religion without the sophistication of foreign religions for various deities.

Characteristics of New Microsporidia S80 Isolated from Silkworm, Bombyx mori L. in Korea (가잠(家蠶)으로부터 분리(分離)된 새로운 Microsporidia S80의 특성(特性))

  • Lim, Jong Sung;Cho, Sae Yun
    • Current Research on Agriculture and Life Sciences
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    • v.1
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    • pp.67-83
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    • 1983
  • The new microsporidia S80 isolated from, Bombyx mori L. in Korea showed ovoid in the morphology of the spores and the size were measured $2.9{\pm}0.28{\mu}$ in length and $1.7{\pm}0.29{\mu}$ width. No other microsporidian spore like this has not been so far isolated from Silkworm. The length of the polar filament extruded in hydrogen peroxide ($H_2O_2$) at $30^{\circ}C$ was $26{\mu}$ of a round cytoplasm on the top. The spores were partly stained with Giemsa, Safranin-O and Gram as the same staining properties as Nosema bombycis, Microsporidia K 79 and other microsporidian spores. The fine structures were observed under scanning eleceron microscope through ultrathin sectioning. The spore wall was composed of three layers ; the thin exospore of an electron dense rippled layer, the thick electron lucent endospore which was thinning considerably at the polar filament insertion point, and the inner limiting membrane. Polar cap present at the sporeapex, with a long polar filament of 12-13 coils, subtending angle of $60^{\circ}$ to spore axis, which is tubular made up of a multilayered and are a benes core, light ring structure enclosing the dance core, the dark ring structure enclosing the inner light ring structure and the other than and light ring structure bounded from cytoplasm. Lamellate polaroplast occupied the anterior part of the spore, and the two neclei with dense nucleoplasm bounded by a double nuclear envelope were cited in the slight downer middle portion of spore. From the characteristics of the shape, size and fine structures, it is certain to reason the Microsporidia S80 belong to the phylum Microspora, class Microspora, order Microsporida, order Microsporida. The shape of two nuclei cited seems to be genus Nosema, but in the classification for the suborder it should be defined wheather pansporoblasts be formed or not and for the genis especial attempts have been made to define the characters which distinguish the disporous genera in the life cycle. Survey through the infection of the bad cocoons during 1980 to 1982 in South Korea the areas contaminated with new microsporidia were revealed 5 provinces of Kyung-Gi, Kang-Won, Chung-Nam and Chun-Nam. Pathological effects inoculated per os at second instar larvae of silkworm, the LD 50 was $7.1{\times}10^7/ml$ as lower pathogenecity than that of Nosema bombycis Naegeli of $1.2{\times}10_7/ml$. While on the other hand the inoculation of the microsporidia at fourth instar larvae lowerd the whole cocoon weight and cocoon shell weight and significant at 1% level. The microsporidia S80 defined it can not be transmitted transovarially from the result of predictive and collective examination of 21 egg batches from the infected female moth.

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Environmental Changes after Timber Harvesting in (Mt.) Paekunsan (백운산(白雲山) 성숙활엽수림(成熟闊葉樹林) 개벌수확지(皆伐收穫地)에서 벌출직후(伐出直後)의 환경변화(環境變化))

  • Park, Jae-Hyeon
    • Journal of Korean Society of Forest Science
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    • v.84 no.4
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    • pp.465-478
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    • 1995
  • The objective of this study was to investigate the impacts of large-scale timber harvesting on the environment of a mature hardwood forest. To achieve the objective, the effects of harvesting on forest environmental factors were analyzed quantitatively using the field data measured in the study sites of Seoul National University Research Forests [(Mt.) Paekunsan] for two years(1993-1994) following timber harvesting. The field data include information on vegetation, soil mesofauna, physicochemical characteristics of soil, surface water runoff, water quality in the stream, and hillslope erosion. For comparison, field data for each environmental factor were collected in forest areas disturbed by logging and undisturbed, separately. The results of this study were as follows : The diversity of vegetational species increased in the harvested sites. However, the similarity index value of species between harvested and non-harvested sites was close to each other. Soil bulk density and soil hardness were increased after timber harvesting, respectively. The level of organic matter, total-N, avail $P_2O_5$, CEC($K^+$, $Na^+$, $Ca^{{+}{+}}$, $Mg^{{+}{+}}$) in the harvested area were found decreased. While the population of Colembola spp., and Acari spp. among soil mesofauna in harvested sites increased by two to seven times compared to those of non-harvested sites during the first year, the rates of increment decreased in the second year. However, those members of soil mesofauna in harvested sites were still higher than those of non-harvested sites in the second year. The results of statistical analysis using the stepwise regression method indicated that the diversity of soil mesofauna were significantly affected by soil moisture, soil bulk density, $Mg^{{+}{+}}$, CEC, and soil temperature at soil depth of 5(0~10)cm in the order of importance. The amount of surface water runoff on harvested sites was larger than that of non-harvested sites by 28% in the first year and 24.5% in the second year after timber harvesting. The level of BOD, COD, and pH in the stream water on the harvested sites reached at the level of the domestic use for drinking in the first and second year after timber harvesting. Such heavy metals as Cd, Pb, Cu, and organic P were not found. Moreover, the level of eight factors of domestic use for drinking water designated by the Ministry of Health and Welfare of Korea were within the level of the first class in the quality of drinking water standard. The study also showed that the amount of hillslope erosion in harvested sites was 4.77 ton/ha/yr in the first year after timber harvesting. In the second year, the amount decreased rapidly to 1.0 ton/ha/yr. The impact of logging on hillslope erosion in the harvested sites was larger than that in non-harvested sites by seven times in the first year and two times in the second year. The above results indicate that the large-scale timber harvesting cause significant changes in the environmental factors. However, the results are based on only two-year field observation. We should take more field observation and analyses to increase understandings on the impacts of timber harvesting on environmental changes. With the understandings, we might be able to improve the technology of timber harvesting operations to reduce the environmental impacts of large-scale timber harvesting.

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Early Clinical Experience in Aortic Valve Replacement Using On-X$^{circledR}$Prosthetic Heart Valve (On-X$^{circledR}$ 기계판막을 이용한 대동맥판 치환술의 조기 임상 경험)

  • 안병희;전준경;류상완;최용선;김병표;홍성범;박종춘;김상형
    • Journal of Chest Surgery
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    • v.36 no.9
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    • pp.651-658
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    • 2003
  • Since the first implanted in September 1997, the use of On-X prosthetic heart valve has been increasing around in the world. This study was designed to assess the feasibility, safety, and the postoperative hemodynamics with this new valve in clinical setting. Material and Method: The current study was carried out on 52 patients undergoing aortic valve replacement with this prosthesis between April 1999 to August 2002 at Chonnam National University Hospital to evaluate the surgical results. 52% of the patients were male and the average age at implant was 50$\pm$13 years. The study followed the guidelines of the AATS/STS. Preoperatively, 32(61.5%) patients were in NYHA functional class III or IV and 2 patients had previous aortic valve surgery. Concomitant cardiac surgery was performed in 71.1%. The implanted valve sizes were 19 mm in 13 patients, 21 mm in 26, 23 mm in 10 and 25 mm in 3, respectively. Mean follow-up was 16.6$\pm$10.5 months (1∼39 months). Echocardiographic assessment was performed pre- and immediate postoperatively, as well as 3, 6, 12 months after surgery, evaluating pressure loss and regression of left ventricular hypertrophy. Result: Mean cardiopulmonary bypass time was 191$\pm$94.7 minutes with an aortic cross-clamp time of 142$\pm$51.7 minutes. There was no early and late mortality, Freedom from adverse events at 1 year in the study were as follows: thromboembolism, 95.6$\pm$6%; bleeding events, 90.2$\pm$4%; paravalvular leakage 92.3$\pm$4%; and overall valve-related morbidity at 1 year was 76.6$\pm$3%. There were no cases of valve thrombosis, prosthetic valve endocarditis and structural or non-structural failure. Left ventricular function at 12 months after surgery (EF=62.7$\pm$9.8%) revealed a statistically significant improvement compared to preoperative investigation (EF=55.8$\pm$15.9%, p=0.006). Left ventricular mass index was 247.3$\pm$122.3 g/$m^2$ on preoperative echocardiographic study, but regressed to 155.5$\pm$58.2 g/$m^2$ at postoperative 1 year (p=0.002). Over the follow-up period a further decrease of peak transvalvular gradients was observed in all patients: 62.5$\pm$38.0 mmHg on preoperative assessment, 18.2$\pm$6.8 mmHg at immediate postoperative period (p < 0.0001), 7.6$\pm$5.09 mmHg (p<0.0001) at 6 month, 18.0$\pm$10.8 mmHg (p<0.0001) at 1 year. Conclusion: The On-X prosthetic heart valve performs satisfactorily in the first 1 year period. Clinical outcome by examining NYHA functional classification revealed especially good results. Effective regression of left ventricular hypertrophy and statistically significant decrease of transvalvular gradient were observed over the first year, but longer-term follow-up of this patient group is needed to establish the expected rates for late valve-related events as well as the long-term clinical efficacy of this valve.

Second allogeneic hematopoietic stem cell transplantation in children to overcome graft failure or relapse after initial transplant (조혈모세포이식 후 생착 실패나 재발한 소아환자에서 2차 이식의 의의)

  • Kim, Dong-Yeon;Kim, Do Kyun;Kim, Soo Young;Kim, Seok Joo;Han, Dong Gyun;Baek, Hee Jo;Kook, Hoon;Hwang, Tai-Ju
    • Clinical and Experimental Pediatrics
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    • v.49 no.12
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    • pp.1329-1339
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    • 2006
  • Purpose : Failure of hematopoietic stem cell transplantation(HSCT) may be encountered in practice because of either relapse of the malignancy or dysfunction of the graft. Second HSCT may be the only option for some patients whose initial HSCT failed. Methods : From May, 1991 to December, 2004, 115 HSCTs were performed at the Pediatric Blood & Marrow Transplantation Center, Chonnam National University. This study was a retrospective analysis of the medical records of 15 patients who received the second HSCT after initial graft. Results : Among eight patients with nonmalignant diseases, two patients underwent the second HSCT because of primary graft failure and five because of late graft rejection. The remaining Fanconi anemia patient was re-transplanted due to development of AML. Two patients died and one experienced primary graft failure, but is still alive. The Kaplan-Meier 5-year overall survival rate was 75 percent and the disease free survival rate was 62.5 percent in nonmalignant diseases. All malignant patients underwent second transplants because of relapses. Four died of relapse and one of treatment-related complications. The Kaplan-Meier 2-year overall and event free survival rate was 28.6 percent each in malignant diseases. Conclusion : Second HSCT for graft dysfunction of nonmalignant disease seems to be feasible and should be considered as a standard practice. The relapse of malignant diseases remains a big obstacle even after the second HSCT, although a small portion of patients might be salvaged. Further investigation of novel therapeutic strategies, as well an the understanding of the biology should be explored.

Clinicopathologic Characteristics of and Surgical Strategy for Patients with Submucosal Gastric Carcinomas (위 점막하층암의 임상병리학적 특징과 수술 방법)

  • Park Chan Yong;Seo Kyoung Won;Joo Jai Kyun;Park Young Kyu;Ryu, Seong Yeob;Kim Hyeong Rok;Kim Dong Yi;Kim Young Jin
    • Journal of Gastric Cancer
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    • v.5 no.2
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    • pp.89-94
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    • 2005
  • Purpose: Early gastric cancer (EGC) has an excellent prognosis compared to advanced gastric cancer. The 5-year survival rate for EGC now exceeds $90\%$, and EGC is recognized as a curable malignancy. The important prognostic factor in EGC is the status of lymph-node metastasis. Despite conserving surgery being suggested for EGC at present, it is of vital importance to select a surgical method appropriate to each individual case. This retrospective study was undertaken to clarify clinicopathologic features and factors related to lymph-node metastasis in submucosal gastric cancer in order to determine an appropriate therapy. Materials and Methods: This study analyzed the clinicopathologic features for 279 patients with a submucosal gastric carcinoma (Group I) and compared with those of patients with mucosal (Group II) or muscularis proprial gastric carcinoma (Group III). All patients were operated on from 1981 to 1999 at Chonnam University Hospital. There were no statistically significant differences among the groups with respect to age, gender, tumor location, hepatic metastasis, or peritoneal dissemination. Results: Positive lymph node metastasis was found in 47 ($16.8\%$) of the 279 patients with a submucosal gastric carcinoma. The incidence of lymph-node metastasis was significantly higher in patients with a submucosal gastric carcinoma than in patients with a mucosal gastric carcinoma ($16.8\%\;vs.\;3.9\%\;$; P<0.01). Therefore, depth of invasion was a significant factor affecting in lymph-node metastasis. The 5-year survival rates were $88.6\%$ for patients in Group I, $95.2\%$ for patients in Group II, and $72.7\%$ for patients in Group III (P<0.01 for Group I vs. Group II; Group I vs. Group III). In patients with a submucosal gastric carcinoma, the survival rate with positive lymph nodes was significantly poorer than that of patients without lymph-node metastasis ($87.3\%\;vs.\;94.2\%$; P<0.01). Conclusion: Gastrectomy with D2 lymph node dissection is an appropriate operative procedure for patients with a submucosal gastric carcinoma.

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