• Title/Summary/Keyword: 성적 성숙

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A Study of Bone Mineral Density of Lumbar Spine by Dual Energy X-ray Absorptiometry (DEXA) in Children (Dual Energy X-ray Absorptiometry를 이용한 소아들의 골밀도에 대한 연구)

  • You, Chur-Woo;Shin, Son-Moon;Park, Yong-Hoon;Kim, Son-Yong
    • Journal of Yeungnam Medical Science
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    • v.10 no.2
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    • pp.369-379
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    • 1993
  • The bone mineral density(BMD) of the lumbar spine (L2-L4) was measured by using dual energy x-ray absorptiometry(Norland XR26 DEXA) in 80 children aged between 2months and 15years (group 1 : 2month-1years, group 2 : 1year-5years, group 3 : 6years-10years, group 4 : 11years-15years). The correlation coefficient of BMD with age, body weight, height and Tanner stage were 0.696, 0.693, 0.717 and 0.636 respectively. There were significant difference in BMD($g/cm^2$) between group 1(BMD : $0.335{\pm}0.175$) and group 2(BMD : $0.627{\pm}0.200$). and group 3(BMD : $0.714{\pm}0.189$) and group 4(BMD : $0.873{\pm}0.163$)(P<0.05). There was no significant difference of BMD between boys and girls(P<0.05). BMD also increased significantly with development of Tanner stages(Tanner stage 1 : $0.547{\pm}0.234$, Tanner stage 2 : $0.783{\pm}0.136$, Tanner stage 3 : $0.998{\pm}0.080$ )(P<0.05). These data indicate that the BMD was correlated with age, body weight, height and Tanner stage significantly and BMD increased significantly during growth spurt occured in 1 to 4years of age and puberty.

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20-Year Experience of Surgical Treatment for Postpneumonectomy Empyema (전폐절제술 후 사강에 발생한 농흉의 치료)

  • 김형렬;김영태;성숙환;김주현
    • Journal of Chest Surgery
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    • v.35 no.7
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    • pp.542-547
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    • 2002
  • Background: Postpneumonectomy empyema(PPE) is an infrequent but potentially life-threatening complication. To date, various surgical efforts have been made to manage this complication. We reviewed our 20-year surgical experience of PPE and long-term follow-up data. Material and Method: Total of 37 patients who were treated for PPE between fan, 1980 and Jun, 2000 were included. Various clinical factors such as micro-organism, operative method and timing, presence of bronchopleural fistula(BPF), underlying disease and fate of empyema cavity were retrospectively reviewed and analyzed. Result: Majority of patients(34) underwent Eloesser operation for effective drainage. There was only one operative mortality. The causative organisms were Staphylococcus species and Pseudomonas species in 46% BPF was found in 20 cases, among which spontaneous closures took place in 4 cases. The chest wall was closed in 40%(8/20) of patients with BPF, compared to 59%(10/17) without BPF. The closure rate was statistically better in patients without BPF(p=0.006). Even though the patients with benign disease showed higher closure rate(50%) than those with lung cancer (31%), the difference was not significant(p=0.25). Conclusion: Eloesser procedure was an effective method for initial drainage of PPE cavity with low operative mortality. Given the findings of low spontaneous closure rate of BPF, aggressive approach to close the BPF is mandatory to achieve the final goal of chest wall closure. It was found that majority of patients still left their chest cavity opened, even after controlling the active inflammation of the empyema cavity. More aggnessive approach for chest wall closure is recommended in all patents with benign disease and in selective patients with lung cancer if there is no evidence of recurrence at several years after the initial operation.

Video-Assisted Thoracic Surgery Lobectomy for Non-Small Cell Lung Cancer: Experience of 133 Cases (폐암에서의 흉강경 폐엽절제술 치험 133예)

  • Kim, Hyeong-Ryul;Cho, Jeong-Su;Jang, Hee-Jin;Lee, Sang-Cheol;Choi, Eun-Suk;Jheon, Sang-Hoon;Sung, Soak-Whan
    • Journal of Chest Surgery
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    • v.42 no.5
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    • pp.615-623
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    • 2009
  • Background: We evaluated the feasibility and the efficacy of Video-Assisted Thoracic Surgery (VATS) lobectomy for treating patients with non-small cell lung cancer (NSCLC) and we compared the outcomes of VATS lobectomy with those of open lobectomy. Material and Method: From 2003 to March 2008, 133 NSCLC patients underwent VATS lobectomy. The patients were selected on the basis of having clinical stage I disease on the chest CT and PET scan. The outcomes of 202 patients who underwent open lobectomy (OL group) for clinical stage I NSCLC were evaluated to compare their results with those of the patients who underwent VATS lobectomy (the VL group). Result: The number of females and the number of patients with adenocarcinoma and stage IA disease were greater in VL group (p<0.05). There was no operative mortality or major complications in the VL group. Conversion to thoracotomy was needed in 8 cases (6%), which was mostly due to bleeding. The chest tube indwelling time and the length of the postoperative hospital stay were significantly shorter in the VL group (p<0.001). The number of dissected lymph nodes and the size of tumor were significantly smaller in the VL group (p<0.001). For the pathologic stage I patients, there was no significant difference in the three-year survival rates between the two groups (p=0.15). Conclusion: VATS lobectomy is a safe procedure with low operative mortality and morbidity. VATS lobectomy is feasible for early stage NSCLC and it provides outcomes that are comparable to those for open lobectomy. Further long-term data are needed.

우리나라의 모자보건사업 (여성과 어린이 건강문제와 증진방안)

  • Park Jeong-Han
    • 대한예방의학회:학술대회논문집
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    • 2002.07b
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    • pp.3-17
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    • 2002
  • 국민건강은 국가발전의 기본조건이다. 국민건강은 건강한 어린이의 출산에서 비롯되고, 건강한 어린이의 출산을 위하여 여성이 건강해야 한다 따라서 여성과 어린이 건강보호와 증진을 위한 모자보건사업은 국가보건사업 중 최우선 사업으로 추진되어야 한다. 우리나라의 모자보건사업은 1960대부터 보건소를 통하여 가족계획, 산전관리, 안전분만유도, 예방접종을 중심으로 하였다. 1980년대에 들어와 전국민의료보험의 실현과 국민생활수준의 향상 등으로 산전관리 수진율과 시설분만율이 급격히 증가하여 1990년대 후반에는 거의 100%에 도달하였고, 가족계획실천율도 1991년에 79.4%까지 증가하여 합계출산율이 1.6으로 감소하였고, 어린이 기본예방접종률도 90%이상이 되어 전염병 발생률이 현저히 감소하였다. 전통적인 모자보건사업 관련 지표들이 이렇게 향상되자 일선 보건요원에서부터 중앙정부의 정책결정권자에 이러기까지 모자보건사업에 대한 관심도가 떨어져 중앙부처의 모자보건업무 담당 부서도 축소되고, 모자보건 사업도 쇠퇴하였다. 그러나 어린이와 여성의 건강실태를 자세히 들여다보면 심각한 문제들이 대두되고 있다. 시설 분만율의 증가에 따라 제왕절개분만율이 40%대까지 급증하였고, 모유수유률은 10%대로 떨어졌다. 어린이의 체격은 커지고 있으나 체력은 떨어지고, 비만한 어린이가 급증하여 당뇨병과 같은 성인병 유병률이 어린이들에게 증가하고, 사고에 의한 어린이 사망과 장애가 늘고 있다. 또한 청소년들의 흡연율과 음주률이 증가하고, 성적 성숙이 빨라지고 사회의 개방풍조로 성(性)활동 연령이 낮아지고 성활동이 증가하여 혼전임신과 성폭력이 증가하고 있다. 여성들은 일찍 단산하고, 폐경 연령은 높아지고, 평균수명은 길어져 중년기와 장년기 그리고 노년기가 길어져 각종 만성질환에 이환될 기회가 늘어났다. 이러한 시기의 중요 건강문제들은 뇌혈관질환, 폐암, 유방암, 골다공증, 뇨실금 등과 같이 해결하기 어려운 것들이다. 이렇게 어린이와 여성들에게 새로운 건강문제들이 대두되고 있으나 이에 대한 대응정책이 없었고, 따라서 새로운 모자보건사업이 개발되지 않았으며 일선 보건요원의 훈련도 없었다. 그리고 이러한 건강실태를 파악하여 대책을 마련하고, 보건사업을 평가할 수 있는 보건정보체계가 없는 실정이다. 1990년대 중반에 소수의 학자들이 어린이와 여성건강문제의 심각성을 제기하고, 모자보건사업 활성화의 필요성을 주장하여 보건복지부가 '모자보건선도보건사업'이라는 이름으로 1999년부터 2001년까지 3년간 23개 보건소에서 시범사업을 시행하였다. 이 시범사업에서는 한정된 자원으로 여성과 어린이 보건문제를 효과적으로 해결하기 위해 새로운 보건사업의 개발과 효율적으로 수행하는 방법의 개발에 역점을 두어 많은 성과를 거두었다. 시범사업의 경험을 바탕으로 2002년에는 전국의 45개 보건소로 확대해나가고 있다. 모자보건선도보건사업에서는 임산부가 대상이었던 기존의 모자보건사업과는 달리 신생아, 영유아, 학동기 어린이, 청소년, 그리고 신혼부부에서부터 장년기 여성에 이르기까지 사업대상을 확대하고 생애주기에 따라 지역사회 건강문제해결을 목표로 한 보건사업을 수행하도록 하였다. 사업수행 과정에서 보건소는 지역내 대학과 협력체계를 구축하여 기술적 지원을 받고, 보건요원의 교육 훈련을 통해 사업기획 능력과 전문지식과 기술을 향상시켰고, 보건교육에 필요한 시설과 장비를 구입하였고, 민간의료기관과 연계하여 보건서비스의 질을 향상시켰다. 모자보건 선도보건소에서 제공하는 서비스는 취약계층 중심의 보건교육, 상담 및 지도, 고위험대상자 조기발견 및 민간기관 의뢰 및 주구관리, 질병 조기발견을 위한 검진 의뢰, 지역 보건통계 생산과 관리, 그리고 지역내 가용자원 안내 등이며, 저소득층에 대해서는 민간의료기관에 의뢰 또는 검진비용을 지원하였다. 이와 같이 지역사회 민간기관과 협력체계를 구축함에 따라 대상자를 지속적으로 관리할 수 있는 정보를 공유하게 되었고, 건강증진 및 질병예방, 치료, 사후관리를 포함한 지속적이고 포괄적인 서비스를 제공할 수 있게 되었다. 특히 고위험 및 건강의심 대상, 임부와 장년기 여성에 대해서는 건강검진서비스를 과감히 민간기관에 의뢰, 위탁하친 보건소는 상담자, 정보관리자로서의 역할로 전환할 수 있었다. 그러나 사업관리자의 양적 평가에 대한 고정관념과 질적 평가에 대한 인식부족, 기본 생정통계와 정보체계의 미비로 인한 부정확한 통계생산, 사업요원의 전문지식과 기술 부족, 그리고 인력부족 등이 문제점으로 대두되었다. 효율적인 사업확산과 조기 정착을 위해 중앙정부의 일관성 있는 정책과 재정적 지원이 필수적이며, 보건정보체계확립, 그리고 공공보건기관과 민간의료기관간의 공식적인 협력체계확립이 필요하다. 사업추진 모니터링 및 평가, 조정을 위하여 중앙에 '모자보건 선도사업 기술지원단'을 구성하여 운영하고, 프로그램 운영이 잘되는 보건소를 특성화 보건소로 지원 육성하고, 사업요원의 업무 적정화를 위한 보건소 조직과 기존 보건사업체계의 평가와 재편이 필요하다. 보건사업요원의 자질 향상을 위한 지속적인 교육 훈련 시스템과 보건통계생산 관리를 위한 정보체계의 구축이 요구된다. 모자보건사업관련 보건교육자료를 수집하고 개발하여 전국 보건소에 공급하는 중앙 보건교육자료 및 정보센터가 필요하다.

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Reproductive Cycle of Natural Population and Artificial Control of Gonadal Development of Ruditapes philippinarum by the Conditions of Water Temperature-Feeding and Starvation (자연산 바지락, Ruditapes philippinarum의 생식주기와 수온-먹이섭이 및 절식조건에 의한 생식소발달의 인위적 제어)

  • Chung, Ee-Yung;Lee, Jung-Sik;Lee, Chang-Hoon;Hur, Sung-Bum
    • The Korean Journal of Malacology
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    • v.18 no.2
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    • pp.83-91
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    • 2002
  • Reproductive cycle of natural population and artificial control experiments of gonadal development by the conditions of water temperatures-feeding and starvation of Ruditapes philippinarum were investigated by histological observations. The reproductive cycle of natural population in females and males can be categorized into five successive stages; early active (February to March), late active (April to May), ripe (April to August), partially spawned (May to October), and spent-inactive stage (August to March). In the artificial control experiments, gonadal development of this species was inhibited by the low water temperature (10$^{\circ}C$). In the experimental group which was exposed to artificial high water temperatures of 19$^{\circ}C$ and 22$^{\circ}C$, gonadal development was accelerated by the higher water temperatures and was faster (about one month) than that in natural populations. In the high water temperatures-feeding experimental group, the gonadal developmental phase was faster in the small-size group than that in the large-size group, and was faster in lower water temperature (10$^{\circ}C$)(p=0.01). The gonad developmental phases in the high water temperature (22-28$^{\circ}C$)-starvation experimental group showed faster (paired sample t-test, p=0.004) than those in the high water temperature-feeding group in females and males. In the high water temperature-feeding experimental group of female and male gonadal developments of small sized group were more sensitive than those in large sized group after 42 days cultivation, However, the gonadal development of male was more sensitive to the lower water temperature than female. On the whole, sexual maturation in the high water temperature experimental group was faster than those in the low water temperature group, and showed a significant difference (paired sample t-test, p=0.001) between female and male. In the starvation experimental group after 42 days, gonadal developments in the high water temperature-large male group showed faster than those in the high water temperature-large female group. However, in small size, gonad developmental phases showed the same pattern between feeding and starvation experimental groups. During the main spawning season, in the high water temperature-starvation experimental groups in females and males, their gonadal development showed faster than that in higher water temperature-feeding experimental group regardless of their sexes and individual sizes and showed a significant difference (paired sample t-test, p=0.004).

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Effects of Reed (Phragmites communis) on Growth Performance, Carcass Characteristics, and Meat Quality in Hanwoo Steers (갈대 급여가 한우 거세우의 발육, 도체 및 육질특성에 미치는 영향)

  • Lee, Sang Min;Chang, Sun Sik;Chung, Ki Yong;Kim, Hyeong Cheol;Choi, Sun Ho;Jeong, Ha Yeon;Yang, Boh Suk;Lee, Sung Sill;Cho, Young Moo
    • Journal of Life Science
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    • v.22 no.10
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    • pp.1392-1398
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    • 2012
  • This study investigated the effects of diet of different forages on growth performance and carcass characteristics of Hanwoo steers. Twenty-one Hanwoo steers were randomly allocated to three groups (fed hay, reed, and reed with rice straw) of seven steers each. Initial and final body weights of control, T1, and T2 groups were 125.5, 128.3, 128.3 kg and 697.4, 614.6, 706.7 kg, respectively. Average daily gain tended to increase in controls (0.70 kg/d) and the T2 group (0.71 kg/d) but not as much in the T1 group (0.60 kg/d); however, there was no significant difference. DMI was not significantly different among the treatment groups, but T1 was relatively lower than the other groups. For the yield traits, carcass weight was not significantly different between controls and the T2 group but was greater in the T2 group compared to the T1 group (p<0.05). Back fat thickness and rib eye area were higher in controls and T2 compared to T1; yield grade (A:B:C, %) was greater in T1 (43:57:0) compared to the other groups (control 0:71:29; T2 29:42:29). For the quality traits, fat color and texture were not significantly different among groups. However, meat color and maturity were significantly greater in T1 compared to T2 (p<0.05). Marbling score and appearance rate of over 1st meat quality grade were greater in the control and T2 groups compared to the T1 group. Based on the results, growth performance, feed utilization, and carcass traits appeared to improve when roughage containing rice straw plus reed was offered. Therefore, reed is worth considering as a roughage source for fattening Hanwoo steers.

Valvuloplasy in Mitral Regurgitation : available option in Young rheumatic mitral regurgitation patients (승모판막 폐쇄부전증에서 판막 성형술의 임상 분석: 젊은 류마티스성 승모판막 폐쇄부전증 환자에서의 판막 성형술)

  • 이재원;송태승;주석중;김종욱;송명근
    • Journal of Chest Surgery
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    • v.32 no.12
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    • pp.1093-1099
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    • 1999
  • 배경 : 류마티스성 승모판막 폐쇄부전증과 퇴행성 승모판막 폐쇄부전증에서 승모판막 성형술의 결과와 비교하여 류마티스성 승모판막 폐쇄부전증에서도 승모팍막성형술이 적합한 치료방법이 될 수 있는지를 알아보았다. 대상 및 방법 : 95년 1월부터 98년 12월 까지 승모판막 성형술을 시행받은 184명의 환자중에서 류마티스성 승모판막 폐쇄부전증 49례(1군)의 퇴행성 승모판막 폐쇄부전증 78례(2군)를 대상으로 하였다. 평균연령은 1군이 36.3$\pm$14.6(16-74세) 2군은 52.5$\pm$13.4(14-77)세였다 총 추적 관찰기간은 1군이 72.2인년 2군이77.2인년이었다 두군에서 수술후와 수술후 6개월 1년 및 이후 1년 단위로 주기적인 심초음파를 시행하였고 이를 통계적 검정하였다. 결과 : 두 군간에 수술전 혈류역학적인 차이를 보이지 않았고 수술전 평균 승모판막 폐쇄 부전의 정도는 1군이 3.0$\pm$0.4, 2군이 3.9$\pm$0.3였으나 수술후 추적 관찰에서 각각 0.9$\pm$0.9와 0.8$\pm$0.7정도의 양호한 판막 성형술의 결과를 보였고 승모판막 면적의 변화나 승모판막에서의 평균압력차이 등 혈류역학적인 결과에도 차이를 보이고 있지 않았다 수술조기 사망과 후기 사망은 없었으며 재수술율은 1군이 인년대비 1.4% 2군이 인년대비 2.6%였고 색전발생율은 1군이 인년대비 2.8% 2군이 1.3%였다. 심내막염발생은 1군에서만 1례있었으며 상기 결과들에서 두군간에 의미있는 차이를 보이고 있지는 않았다 결론 : 향후 장기적인 추적 관찰이 필요하나 중기 성적에서 승모판막 성형술이 류마티스성 승모판막 폐쇄 부전증에서도 효과적인 치료방법임을 알수 있었다.다 출생후 폐포막의 FN의 활성은 출생후 5일 및 7일에 최고주에 달했다. 출생직후 1-2일경에 혈관의 조직내 FN의 활성이 양성을 나타내지만 3일이후 활성이감소되었다. 폐포대식세포내 FN의 활성은 출생후 증가되었다. 폐조직내 소기관지의 FN의 활성은 출생후 완만하게 상승되었다. 큰 폐포세포는 출생 1-3일에 일정량의 FN 반응이 세포질과 미세융모내에 관찰되었다. 결론 : 이상과 같은 결과로 흰쥐의 폐포의 분화과정이 계속되는 출생후 폐에서 FN의 분비는 7일이내에 성숙흰쥐의 폐포내 반응과 비슷한 반응으르 보이며 이때 폐의 실질조직은 분화가 거의 완료되었을 것으로 사료되었고 큰 폐포세포에서도 FN이 분비되는 것으로 결론지울수 있다.X>에서 $1,332.75{\mu}g/mL$으로 최 대값을 나타내었으며, 추출시간 4.24시간 및 시료에 대한 용매비 9.71 mL/g에서 가장 높게 나타났다. 추출온도가 높고, 추출시간이 증가할수록 총 polyphenol 함량이 증가하는 경향을 나타내었다. Gallic acid 함량은 $65.84^{\circ}C$에서 $30.51{\mu}g/mL$으로 최대값을 나타내 었으며, 추출시간 1.65시간 및 시료에 대한 용매비 17.17mL/g에서 가장 높은 추출율을 보였다. Gallic acid 함량에 대한 추출조건의 영향은 추출시간과 용매비에 영향을 받는 것으로 나타났으며, 설정된 범위 내에서 온도에 대한 영향은 거의 나타나지 않는 것으로 나타났다. 실험연구가 더 필요하리라 본다. 혈액학적 변화를 유도하고 환자의 연령, 혈소판 수, 대동맥 차단 시간, 체외 순환 시간, 술후 PT 및 aPTT와 같은 다인적 상황들이 술후 출혈에 영향을 미친다는 점들을 시사하고

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Long Term Results of Bronchial Sleeve Resection for Primary Lung Cancer (원발성 폐암 환자에서의 기관지 소매 절제술의 장기 성적)

  • Cho, Suk-Ki;Sung, Ki-Ick;Lee, Cheul;Lee, Jae-Ik;Kim, Joo-Hyun;Kim, Young-Tae;Sung, Sook-Whan
    • Journal of Chest Surgery
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    • v.34 no.12
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    • pp.917-923
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    • 2001
  • Background : Bronchial sleeve resection for centrally located primary lung cancer is a lung-parenchyma-sparing operation in patients whose predicted postoperative lung function is expected to diminished markedly. Because of its potential bronchial anastomotic complications, it is considered to be an alternative to pneumonectomy. However, since sleeve lobectomy yielded survival results equal to at least those of pneumonectomy, as well as better functional results, it became and accepted standard procedure for patients with lung cancer who have anatomically suitable tumors, regardless of lung function. In this study, from analyzing of occurrence rate of postoperative complication and survival rate, we wish to investigate the validity of sleeve resection for primary lung cancer. Material and Method : From January 1989 to December 1998, 45 bronchial sleeve resections were carried out in the Department of Thoracic Surgery of Seoul National University Hospital. We included 40 men and 5 women, whose ages ranged from 23 to 72 years with mean age of 57 years. Histologic type was squamous cell carcinoma in 35 patients, adenocarcinoma in 7, and adenosquamous cell carcinoma in 1 patients. Right upper lobectomy was peformed in 24 patients, left upper lobectomy in 11, left lower lobectomy in 3, right lower lobectomy in 1, right middle lobecomy and right lower lobectomy in 3, right upper lobectomy and right middle lobecomy in 2, and left pneumonectomy in 1 patient. Postoperative stage was Ib in 11, IIa in 3, IIb in 16, IIIa in 13, and IIIb in 2 patients. Result: Postoperative complications were as follows; atelectasis in 9, persistent air leakage for more than 7 days was in 7 patients, prolonged pleural effusion for more than 2 weeks in 7, pneumonia in 2, chylothorax in 1, and disruption of anastomosis in 1. Hospital mortality was in 3 patients. During follow-up period, bronchial stricture at anastomotic site were found in 7 patients under bronchoscopy, Average follow-up duration of survivals(n=42) was 35.5$\pm$29 months. All of stage I patients were survived, and 3 year survival rate of stage II and III patients were 63%, 21%, respectively. According to Nstage, all of N0 patients were survived and 3 year survival rates of Nl and N2 were 63% and 28% respectively. Conclusion: We suggest that this sleeve resection, which is technically demanding, should be considered in patients with centrally located lung cancer, because ttlis lung-saving operation is safer than pneumonectomy and is equally curative.

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Studies on the Occurrence of Upland Weeds and the Competition with Soybeans (전지(田地)와 콩밭에 있어서 잡초(雜草)의 발생(發生) 및 경합(競合)에 관한 조사(調査) 연구(硏究))

  • Lee, Key-Hong;Lee, Eun-Woong
    • Korean Journal of Weed Science
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    • v.2 no.2
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    • pp.75-113
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    • 1982
  • Studies were carried out 1) to define the shape and size of sampling quadrat and its number of observations for weed experiments, 2) to characterize the growth and community of major summer weeds under upland condition and 3) to investigate the factors influencing competition between weeds and soybeans under weed-free and weedy conditions in early and late season cultures. No significant difference was noted among different shapes of quadrat (regular, rectangular, band, and circular) in the sampling efficiency of weeds. The results also suggested that the minimum size of quadrat was 0.25$m^2$ and the minimum number of replication was 2 times per plot. The major dominant weeds were about 10 species in the experimental field and the total number of weeds was in the range of 70 - 1,600 plants per $m^2$. Among the weeds Digitaria sanguinalis and Portulaca oleracea were the most dominant species. Growth amount and reproduction capability were also measured by weed species. Five different weed communities were identified in the field. The degree of dispersion by weed species and association among weeds were investigated. Intra-(within soybeans) and inter-specific (between soybeans and weeds) competition were studied in early and late season cultures of soybeans. The average yield of soybeans per plant was significantly decreased in both season cultures due to intra-specific competition as the planting density of soybeans increased, On the other hand, the average yield of soybeans per l0a was proportionally increased to the increase of planting density and the rate of its increase was more significant under weedy than weed-free condition. Most of the agronomic characteristics of soybeans were affected by weeds and its degree was greater in sparse planting than in dense planting and in early season than in late-season culture. Digitaria sanguinalis was the most competitive to soybeans in early season and both of Digitaria sanguinalis and Portulaca oleracea affected primarily the growth of soybeans in late season with about the same competitiveness. The occurrence of weeds was significantly decreased in early season and slightly decreased in late-season by dense planting of soybeans. The total growth amount of weeds was also considerably decreased by increase of soybean planting density both in early- and late-season cultures. The occurrence of Digitaria sanguinalis which was the most dominant in both seasons, and its growth amount was significantly decreased as the planting density of soybean was increased. On the other hand, the occurrence of Portulaca oleracea which was only dominant in late-season culture did not show significant response to the planting density of soybeans.

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