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Growth and Characterization of AgGa$Se_2$ Single Crystal Thin Films by Hot Wall Epitaxy (Hot Wall Epitaxy (HWE)법에 의한 AgGa$Se_2$ 단결정 박막 성장과 특성)

  • Hong, Gwang-Jun;Lee, Gwan-Gyo;Park, Jin-Seong
    • Korean Journal of Materials Research
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    • v.11 no.5
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    • pp.419-426
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    • 2001
  • The stochiometric $AgGaSe_2$ polycrystalline mixture of evaporating materials for the $AgGaSe_2$ single crystal thin film was prepared from horizontal furnace. To obtain the single crystal thin films, $AgGaSe_2$ mixed crystal and semi-insulating GaAs(100) wafer were used as source material and substrate for the Hot Wall Epitaxy (HWE) system, respectively. The source and substrate temperature were fixed at$ 630^{\circ}C$ and $420^{\circ}C$, respectively. The thickness of grown single crystal thin films is 2.1$\mu\textrm{m}$. The single crystal thin films were investigated by photoluminescence and double crystal X-ray diffraction(DCXD) measurement. The carrier density and mobility of AgGaSe$_2$ single crystal thin films measured from Hall effect by van der Pauw method are $4.89\Times10^{17}$ cm$^{-3}$ , 129cm2/V.s at 293K, respectively. From the Photocurrent spectrum by illumination of perpendicular light on the c-axis of the AgGaSe$_2$ single crystal thin film, we have found that the values of spin orbit splitting $$\Delta$S_{o}$ and the crystal field splitting $\Delta$C$_{r}$, were 0.1762eV and 0.2474eV at 10K, respectively. From the photoluminescence measurement of AgGaSe$_2$ single crystal thin film, we observed free excision (EX) observable only in high quality crystal and neutral bound exciton ($D^{o}$ , X) having very strong peak intensity. And, the full width at half maximum and binding energy of neutral donor bound excition were 8mev and 14.1meV, respectively. By Haynes rule, an activation energy of impurity was 141 meV.ion energy of impurity was 141 meV.

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Analysis of Environmental Characteristics in Habitat of Amanita hemibapha (달걀버섯 발생지의 환경특성 분석)

  • Sou, Hong-Duck;Hur, Tae-Chul;Jung, Sung-Cheol;Joo, Sung-Hyun;Park, Hyun
    • The Korean Journal of Mycology
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    • v.39 no.3
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    • pp.164-170
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    • 2011
  • Amanita hemibapha is a kind of mycorrhizal mushroom which has a relation with host plants and environmental factors. For the purpose of studying the relationship between environmental factors and mushrooms, in this study we conducted to investigate the soil physicochemical properties, the distribution of plants and the diversity of mushrooms in Gwangyang, Chungdo and Daegu. Soil texture in habitate of Amanita hemibapha was Sandy Loam and Sandy Clay Loam which contains a high rate of sand. Soil pH was approximately 5.0 in all study sites. Total nitrogen contents, C/N ratio and available phosphate($P_2O_5$) were the highest at the Chungdo. However, Gwangyang and Chungdo represent similar Cation Exchange Capacity(C.E.C) and Daegu has much less than other areas. Exchangeable cations, $Ca^{2+}$ content was higher at Gwangyang and Chungdo than Daegu and $Na^+$ content was the highest at Chungdo among three sites. Daegu has much $Mg^{2+}$ contents followed by Chungdo and Gwangyang. Interestingly, $K^+$ content listed in reverse order of $Mg^{2+}$ at Gwangyang, Chungdo and Daegu. The main woody plants in study sites are confirmed as Carpinus laxiflora, Quercus mongolica, Q. serrata and Pinus densiflora. Quercus species are found as a common species in three study sites. Lastly, 8 family and 12 species of mushrooms are emerged in Gwangyang, also 8 family and 12 species and 5 family and 10 species are found in Chungdo and Daegu, respectively. Amanita pantherina, Boletus edulis, Tylopilus felleus and Marasmius maximus, which found in study sites, are also kind of mycorrhizal mushroom same as A. hemibaph. By using correspondence analysis, Q. mongolica, Q. serrata, Q. variabilis and C. laxiflora are expected to as a host plant of A. hemibapha.

The Stone Buddha Statue of Sangunsa Temple at Bukhansan in Goyang, Gyeonggi Province (고양 상운사 석불좌상과 조선 전기 조각 양식의 전통과 모색)

  • Shim, Yeoung shin
    • Korean Journal of Heritage: History & Science
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    • v.52 no.4
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    • pp.246-263
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    • 2019
  • The stone Buddha statue of Sangunsa Temple at Bukhansan in Goyang, Gyeonggi Province, is an excellent example of stone Buddha statues created in the late 15th century. On the base of the figure, there is an inscription, which informs that it was produced in 1497. In recognition of this significance, it was recently designated as a tangible cultural asset in Gyeonggi-do. Thus, this paper tried to evaluate the value of the statue by analyzing iconography and style. The characteristics of a typical 15th-century style that the Buddha statue of Sangunsa Temple shows are the form of ushnisha, the way clothes are worn, the form of a w-shaped chest muscle, and the simple lotus pedestal. On the other hand, the elongation of the waist and the disappearance of the waistband on undergarments are new forms of Buddha statues in the 16th century. Besides, parting the hair in the middle of the head and leaf-shaped short ribbon draped on undergarments are unique features that only appear on the statue of Sangunsa Temple. Sangunsa has been known to be built in the early 18th century based on Bukanji compiled by Seongneung in 1745, and Bongeunbonmalsaji composed in 1943. However, the statue was created in the late 15th century, before the establishment of the temple in the early 18th century. Therefore, this paper briefly reviewed the history of Sangunsa Temple, focusing on the initial period, referring to the historical sites and the relics that were passed on to the temple, as well as the literature records. The data newly referred to in the study are as follows: Sangunsa Stone Pagoda, presumed to be from the Goryeo Dynasty; the Stone Buddha Statue of Sangunsa; Wooden Amita Triad Buddha Statue of Sangunsa. According to the data and contrary to previously-held beliefs, Sangunsa Temple is believed to have been operating since the Goryeo Dynasty. It can be inferred through analysis of the stone Buddha statue of Sangunsa Temple that the size of the Temple before the 18th century was not very large.

A Method for Establishing Chronology of Cloud Patterns Based on the Cover Patterns of Oegyujanggak Uigwe Books in the Late Joseon Period (외규장각 의궤 책의 문양을 통한 운보문 편년 설정 방법)

  • Lee, Eunjoo
    • Korean Journal of Heritage: History & Science
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    • v.52 no.4
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    • pp.18-37
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    • 2019
  • This study derived a method for establishing the chronology of cloud patterns by examining the arrangement of the treasure motifs in the cloud pattern used in the relevant pattern-decorated book covers of 89 Oegyujanggak Uigwe books, which are currently housed in the National Museum of Korea. The cloud pattern with a treasure motif was used in the covers of a total of 89 books from King Hyojong Gukjangdogam Uigwe (1659) to Sadoseja Garyedogam Uigwe (1744), spanning 86 years. First, to analyze the cloud pattern, it should be broken down into smaller parts to the extent that the different shapes of treasure motifs can be recognized. Secondly, the method of decoding the pattern is as follows: First, check whether the pattern is arranged in one or two directions from the vertex of the cloud's head, and determine the direction of the cloud tail. Then, decode the treasure motif's arrangement starting from the vertex of the cloud's head toward the direction the tail of manja is headed. Record the findings of this decoding process by categorizing them. Thirdly, as a result of the analysis, a total of 28 types of cloud patterns with treasure motifs were identified in 89 books. There were 45 types of treasure motifs used in such patterns. Finally, we have concluded that applying the method of decoding the treasure motif in the cloud pattern to portraits, excavated costumes, and various relics can be useful to establish the chronology of cloud patterns in the late Joseon period. The method suggested in this study is called 'The Reading Method of Chronology in Cloud Pattern with Treasure Motifs' (also 'Jeung-ha Cloud Pattern Reading Method').

Small-Angle X-ray Scattering Station 4C2 BL of Pohang Accelerator Laboratory for Advance in Korean Polymer Science

  • Yoon, Jin-Hwan;Kim, Kwang-Woo;Kim, Je-Han;Heo, Kyu-Young;Jin, Kyeong-Sik;Jin, Sang-Woo;Shin, Tae-Joo;Lee, Byeong-Du;Rho, Ye-Cheol;Ahn, Byung-Cheol;Ree, Moon-Hor
    • Macromolecular Research
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    • v.16 no.7
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    • pp.575-585
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    • 2008
  • There are two beamlines (BLs), 4C1 and 4C2, at the Pohang Accelerator Laboratory that are dedicated to small angle X-ray scattering (SAXS). The 4C1 BL was constructed in early 2000 and is open to public users, including both domestic and foreign researchers. In 2003, construction of the second SAXS BL, 4C2, was complete and commissioning and user support were started. The 4C2 BL uses the same bending magnet as its light source as the 4C1 BL. The 4C1 BL uses a synthetic double multilayer monochromator, whereas the 4C2 BL uses a Si(111) double crystal monochromator for both small angle and wide angle X-ray scattering. In the 4C2 BL, the collimating mirror is positioned behind the monochromator in order to enhance the beam flux and energy resolution. A toroidal focusing mirror is positioned in front of the monochromator to increase the beam flux and eliminate higher harmonics. The 4C2 BL also contains a digital cooled charge coupled detector, which has a wide dynamic range and good sensitivity to weak scattering, thereby making it suitable for a range of SAXS and wide angle X-ray scattering experiments. The general performance of the 4C2 BL was initially tested using standard samples and further confirmed by the experience of users during three years of operation. In addition, several grazing incidence X-ray scattering measurements were carried out at the 4C2 BL.

Effects of Boyanghwano-Tang on the Development of Experimentally-induced Endometriosis in the Rats (보양환오탕(補陽還五湯)이 실험적으로 유발된 흰쥐의 자궁내막증에 미치는 영향)

  • Lim, Sung-Min;Lee, Dong-Nyung;Seo, Il-Bock;Kim, Hyung-Jun
    • The Journal of Korean Obstetrics and Gynecology
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    • v.23 no.3
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    • pp.56-77
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    • 2010
  • Purpose: This study was performed to investigate effects of Boyanghwano-Tang on the development of experimentally-induced endometriosis in rats. Methods: Endometriosis was induced in rats by autotransplanting uterine tissue to the peritoneum and divided them into three groups: (1) sham-operated group(n=8), (2) surgically induced endometriosis and untreated control group (n=8), (3) surgically induced endometriosis and Boyanghwano-Tang treated group. Boyanghwano-Tang was orally administrated for 15 days after operation. Then we measured the body weight, the volume of endometriotic implants, the weight of uterus and ovary, and investigated the concentration of cytokines (MCP-1, TNF-$\alpha$, IL-$1{\beta}$, IL-6) in peritoneal fluids. Histopathology, immunohistochemistry for COX-2 and VEGF, and histochemistry for mast cell in transplanted uterine tissue were performed. Results: - The volume($mm^3$) of endometriotic implants in Boyanghwano-Tang treated group ($122.3{\pm}45.0$) was significantly decreased(p<0.05) compared with control group($222.1{\pm}109.1$). - The concentration(pg/$m{\ell}$) of MCP-1 in peritoneal fluids in Boyanghwano-Tang treated group($1026.3{\pm}196.5$) was significantly decreased(p<0.05) compared with control group($1412.5{\pm}345.7$). - The concentration(pg/$m{\ell}$) of TNF-$\alpha$ in peritoneal fluids in Boyanghwano-Tang treated group($936.5{\pm}94.3$) was significantly decreased(p<0.01) compared with control group($1126.2{\pm}139.9$). - The concentration(pg/$m{\ell}$) of IL-$1{\beta}$ in peritoneal fluids in Boyanghwano-Tang treated group($78.5{\pm}13.3$) was significantly decreased(p<0.01) compared with control group($105.3{\pm}17.6$). - The concentration(pg/$m{\ell}$) of IL-6 in peritoneal fluids in Boyanghwano-Tang treated group($107.4{\pm}15.8$) was decreased compared with control group($122.8{\pm}19.3$). - Histopathologically, proliferation of endometriotic epithelia, infiltration of inflammatory cells and angiogenesis in transplanted uterine tissue of Boyanghwano-Tang treated group were weakly observed than those of control group. - The percentage of positive epithelial layers for COX-2 in Boyanghwano-Tang treated group($51.5{\pm}14.1$) was significantly decreased(p<0.01) compared with control group($75.1{\pm}16.3$). - The VEGF expression of endometriotic epithelia, neovascular endothelia and stromal cells in transplanted uterine tissue of Boyanghwano-Tang treated group were weakly observed than those of control group. - The number of mast cells in adjacent tissue of transplanted uterine tissue in Boyanghwano-Tang treated group($75.9{\pm}13.1$) was decreased compared with control group($91.0{\pm}28.3$). Conclusion: On the basis of these results, we concluded that Boyanghwano-Tang have inhibiting effects on the development of transplanted uterine tissue. And these effects may be related with decreased production of MCP-1, TNF-$\alpha$, IL-$1{\beta}$ and decreased expression of COX-2 and VEGF by administration of Boyanghwano-Tang.

Treatment Outcome and Analysis of the Prognostic Factors of Ductal Carcinoma in situ Treated with Breast Conserving Surgery and Radiotherapy (유방 관상피내암의 유방 보존술 후 방사선 치료의 성적과 예후 인자 분석)

  • Kim, Kyoung-Ju;Huh, Seung-Jae;Park, Won;Yang, Jeong-Hyeon;Nam, Seog-Jin;Kim, Jeong-Han;Lee, Sung-Kong;Lee, Jee-Hyun;Kang, Sung-Soo;Lee, Jeong-Eun;Kang, Min-Kyu;Park, Young-Je;Nam, Hee-Rim
    • Radiation Oncology Journal
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    • v.22 no.1
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    • pp.11-16
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    • 2004
  • Purpose: To evaluate the survival rate, local failure rate and patterns of failure, and analyze the prognostic factors affecting local relapse of ductal carcinoma in situ treated with breast conserving surgery and radiotherapy Materials and Methods: From June 1995 to December 2001, 96 patients with ductal carcinoma in situ treated with breast conserving surgery and radiotherapy were retrospectively analyzed. The operations were either local or wide excision in all patients, with an axillary lymph node dissection performed in some patients. Radiation dose to the whole breast was 50.4 Gy, over 5 weeks, with 1.8 Gy daily fractions, with additional doses ($10\~14$ Gy) administered to the primary tumor bed in some patients with close ($\leq$2 mm) or positive resection margin. The median follow-up period was 43 months (range $10\~102$ months). Results: The 5-year local relapse free survival and overall survival rates were 91 and $100\%$ respectively. Local relapse occurred in 6 patients ($6.3\%$). Of the 6 recurrences, one was invasive ductal cell carcinoma. With the exception of one, all patients recurred 2 years after surgery. There was no regional recurrence or distant metastasis. Five patients with local recurrence were salvaged with total mastectomy, and are alive with no evidence of disease. One patient with recurrent invasive ductal cell carcinoma will receive salvage treatment. On analysis of the prognostic factors affecting local relapse, none of the factors among the age, status of resection margin, comedo type and nuclear grade affected local relapse. Operation extent also did not affect local control (p=0.30). In the patients with close resection margin, boost irradiation to the primary tumor bed did not affect local control (p=1.0). Conclusions: The survival rate and local control of the patients with ductal carcinoma in situ treated with breast conserving surgery and radiotherapy were excellent. Close resection margin and boost irradiation to the primary tumor bed did not affect local relapse, but further follow-up with much more patients is needed.

Radiotherapy of Supratentorial Primitive Neuroectodermal Tumor (천막상부 원시신경외배엽 종양의 방사선요법)

  • Kim Il Han;Yoo Hyung Jun;Cho Young Kan;Kim Dae Yong
    • Radiation Oncology Journal
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    • v.15 no.1
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    • pp.11-18
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    • 1997
  • Purpose : To evaluate the efficacy of combined treatment of surgery and chemoradiotherapy for supratentorial primitive neuroectodermal tumors (SPNET) and obtain the Prognostic factors and complications Materials and Methods .The a9e of 18 patients ranged from 1 to 27 years (median=5 years). There were 12 males and 6 females The extents of surgery were gross total (n:9), subtotal (n:8), biopsy only (n: 1). Craniospinal radiotherapy was delivered to all the patients except 2 patients who were treated only with the whole brain and primary lesion. Radiation dose were 3120-5800cGy (median=5460) to primary mass, 1500-4200cGy (median=3600cGy) to the whole brain and 1320-3600cGy (median= 2400 cGy) to the spinal axis. Chemotherapy was done in 13 patients. Median follow-up period was 45 months ranged from 1 to 89 months. Results : Patterns of failure were as follows; local recurrence (1), multiple intracranial recurrence (2), spinal seeding (3), craniospinal seeding (2) and multiple bone metastasis (1). Two of two patients who did not received craniospinal radiotherapy failed at spinal area. All the relapsed cases died at 1 to 13 months after diagnosis of progression. The 2- and 5-rear overall survival rates were $61\%\;and\;49\%$, respectively The a9e, sex, tumor location did not influence the survival but aggressive resection with combined chemotherapy showed better outcome. Among 9 survivors, complications were detected as radiation necrosis (n=1), hypopituitarism (n=2), cognitive defect(n=1), memory deficit (n=1), growth retardation (n=1). Conclusion : To improve the results of treatment of SPNET, maximal surgical resection followed by radiation therapy and chemotherapy is necessary. The extended radiation field including craniospinal axis may reduce the recurrence in spinal axis.

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Prenatal Deaths and External Malformations Caused by X-Irradiation during the Preimplantation Period of ddy Mice (임신 ddy Mice에서 착상전기 방사선 조사에 따른 산전 사망 및 외부 기형 발현)

  • Ro, Hee-Jeong;Choi, Ihl-Bhong;Gu, Yeun-Wh
    • Radiation Oncology Journal
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    • v.16 no.3
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    • pp.233-243
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    • 1998
  • Purpose : To evaluate the effects of X-irradiation on prenatal deaths, i.e., preimplantation deaths, embryonic deaths and fetal deaths, and on external malformations in precompacted preimplantation ddy mice Materials and Methods : Pregnant mice (n=85) obtained by limiting the mating time to from 6 to 9 A.M., were segregated into 11 groups. The first five groups (n=26) were irradiated with X-ray doses of 0.1 0.5, 0.75, 1.5, and 3 Gy, respectively, at 24 h post conception (p.c.) of the preimplantation Period. The second five (n=27) groups were irradiated at the same X-ray doses, respectively, but at 48 h p.c. of the preimplantation period. The last group (n=32) was the control group. The uterine contents were examined on the 18th day of gestation for prenatal deaths and external malformations. Results : 1) A statistically significant increase in preimplantation deaths with increasing dose was observed in the experimental groups irradiated at 24 h p.c. and in the groups irradiated at 48 h p.c., as compared to the control group. The threshold dose was close to 0.05 Gy and 0.075 Gy for the irradiations at 24 h p.c. and 48 h p.c. respectively. 2) A statistically significant increase in embryonic deaths with increasing dose was observed in all irradiation groups, except the group irradiated with a dose of 0.1 Gy at 48 h p.c.. 3) No fetal deaths were found in any experimental group. 4) In the experimental groups irradiated at 24 h p.c. anomalies increased with statistical significance, as compared with the control group : 2 exencephalies, 2 open eyelids, 3 anophthalmias, 2 cleft Palates, 2 gastroschisis, 1 abdominal wall defect. 1 leg defect, and 2 short tail anomalies: the threshold dose for external malformations was close to 0.2 Gy at 24 h p.c.. In the groups irradiated at 48 h p.c., 1 open eyelid and 2 short tail anomalies were observed, but there was no statistical significance in those malformations. Conclusion : The results of this study reveal that X-irradiation of precompacted preimplantation ddy mice causes not only preimplantation deaths and embryonic deaths but also external malformations. In addition, external malformations were observed in our experiments at diagnostic doses, including 0.1 and 0.5 Gy. For this reason, we recommend that irradiation should be avoided during the preimplantation period by applying Rugh's 10-day rule.

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The Palliative Effect of Endobronchial Brachytherapy for Previously Irradiated Patients with Lung Cancer (이전에 외부방사선치료를 받은 폐암 환자에서 기관지내 근접치료의 고식적 효과)

  • Park, Young-Je;Kim, Kwang-Taik;Yang, Dae-Sik;Lee, Suk;Kim, Chul-Yang
    • Radiation Oncology Journal
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    • v.25 no.3
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    • pp.177-184
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    • 2007
  • Purpose: To evaluate the palliative effect of endobronchial brachytherapy (EBB) for patients with lung cancer that previously received external beam radiotherapy (EBRT). Materials and Methods: From July 1992 to May 2003, 29 patients with a recurrent or persistent lung cancer were treated with palliative EBB at our institute. EBB consisted of three fractions (once a week) of a dose of 5 Gy using the high dose-rate remote afterloader. Symptomatic improvement was assessed subjectively, and patients were divided into two groups according to whether symptoms were improved or not. Factors such as age, performance status, duration from EBRT to EBB and the location of the tumor were compared between the improved and unimproved groups of patients. Results: Overall symptomatic improvement was found in 27 out of 52 symptoms (52%). Improvement as to the type of symptoms was seen in 41 %, 50%, 82% and 33% of patients with cough, dyspnea, hemoptysis, and obstructive pneumonia respectively. The rate of improvement of hemoptysis was more than that of cough (p<0.05). The median time to symptom relapse was 5 months. The improved patient group (n=17, 59%) had a better performance status and longer duration from EBRT to EBB than the unimproved patient group (p<0.05). Lesions located in the distal trachea and/or main bronchus were found more frequently in the improved group of patients than in the unimproved group of patients, but the difference was not statistically significant (p=0.06). Fatal complications developed in two patients (7%), which were a hemoptysis and bronchopleural fistula respectively. Conclusion: Symptom improvement was found in 60% of patients after EBB and improvement was maintained for 5 months. Palliative EBB, even when EBRT was given previously, can be effective for a patient that has an endobronchial symptom, such as hemoptysis, and for a patient with good performance and a long duration from previous EBRT to EBB.