RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제
      • 좁혀본 항목 보기순서

        • 원문유무
        • 음성지원유무
        • 원문제공처
          펼치기
        • 등재정보
          펼치기
        • 학술지명
          펼치기
        • 주제분류
          펼치기
        • 발행연도
          펼치기
        • 작성언어
        • 저자
          펼치기

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • Brain SPECT 영상의 Attenuation Correction 방법들에 대한 비교

        조진우,김창호,나수경,이귀원,Jo, Jin U,Kim, Chang Ho,Na, Soo Kyung,Lee, Gui Won 대한핵의학기술학회 2012 핵의학 기술 Vol.16 No.2

        이 연구의 목적은 Brain SPECT (Single Photon Emission Computed Tomography)의 Non-attenuation correction (AC-non) 영상에 대한 attenuation correction(AC) 방법 중 Chang's method와 CT based attenuation correction(AC-CT) 사이의 count를 비교하기 위함이다. phantom study는 증류수로 채워진 hoffman 3D phantom에 $^{99m}Tc$ 37Mbq을 투여하였고, patient study는 normal volunteer에 $^{99m}Tc$-HMPAO 750Mbq를 정맥주입하고 Siemens사의 Symbia T6로 Brain SPECT 영상을 획득하였고 뇌 정량 분석을 하였다. 각각의 방법들을 적용한 transverse image는 같은 위치에서 재구성 되었으며 각각 10, 20, 30번째 slice에서 6개의 region of interest(ROI)를 그려 AC-non 과 AC-CT 그리고 Chang's method의 count를 비교하였다. phantom study에서 AC-non, AC-CT, Chang's method의 각각 평균 count는 $4606.8{\pm}511.3$, $16794.6{\pm}2429.4$, $8752.6{\pm}896.5$이었으며 patient study에서 $5460.8{\pm}519.6$, $15320{\pm}1171.6$, $12795{\pm}1422.1$이었다. phantom study에서 AC-CT와 AC-non 사이의 비는 3.70이고 Chang's method와 AC-non 사이의 비는 1.92였으며 patient study에서는 각각 2.85, 2.38이었다. 우리는 이 연구를 통하여 AC-CT가 Chang's method보다 더 높은 AC을 해준다는 걸 알 수 있었다. 그리고 Chang's method는 patient study에서의 AC 값이 phantom study에서의 AC값보다 더 높다는 것을 알 수 있었다. brain SPECT/CT를 시행하는 경우 scatter correction을 같이 시행하고 bone에 의한 감쇠 정보를 반영할 수 있는 AC-CT가 chang's method보다 정확하다 할 수 있겠다. Purpose : The purpose of this study was to compare count between Chang's method and CT-based attenuation correction (AC-CT) among the attenuation correction (AC) methods for non-attenuation correction (AC-non) images of Brain SPECT (Single Photon Emission Computed Tomography). Materials and Methods : We injected $^{99m}Tc$ 37Mbq in a Hoffman 3D phantom filled with distilled water in the phantom study, and injected intravenously $^{99m}Tc$-HMPAO 740Mbq in a normal volunteer in the patient study, and then obtained Brain SPECT images with Symbia T6 of Siemens and conducted quantitative brain analysis. Transverse images to which each method was applied were rebuilt at the same position, and 6 regions of interest (ROI) were drawn on each of Slice No. 10, 20 and 30 and then the counts of AC-non, AC-CT and Chang's method were compared. Results : The mean counts of AC-non, AC-CT and Chang's method were $4606.8{\pm}511.3$, $16794.6{\pm}2429.4$, and $8752.6{\pm}896.5$, respectively, in the phantom study and $5460.8{\pm}519.6$, $15320{\pm}1171.6$ and $12795{\pm}1422.1$, respectively, in the patient study. In the phantom study, the ratio of AC-CT to AC-non was 3.70 and the ratio of Chang's method to AC-non was 1.92, and in the patient study, they were 2.85 and 2.38, respectively. Conclusion : From this study, we found that AC-CT makes higher AC than Chang's method. In addition, when Chang's method was used, AC in the patient study was higher than that in the phantom study. These results need to be considered also in other examinations.

      • SCOPUSKCI등재

        사염화탄소 투여 흰쥐에서 간섬유화 진행에 따른 Propranolol 의 약동학적 지표들의 변화

        이민호,강주섭,강문수,윤병철,이오영,함준수,변재원,윤창옥 대한간학회 2001 Clinical and Molecular Hepatology(대한간학회지) Vol.7 No.2

        Background/Aims : This study was designed to determine the effect of hepatic fibrotic severity on pharmacokinetics of propranolol in CC1q - treated rats. Methods - 1 mL/kg of 10% CC14 in olive oil was injected intramuscularly to rats twice weekly for 4, 6, 8 and 10 weeks, respectively (n=6). Control (n=6) was a sham - injected equal dose of olive oil for 10 weeks. After intravenous bolus injection of 2 mg/kg propranolol to rats, the serum propranolol concentrations were analyzed for 4 hours at various time points by a HPLC - fluorimetric system, and pharmacokinetic parameters such as Co, MRT, AUC, Vdss, tl/2(p) and CLp were determined. Then, a small amount of hepatic tissue was obtained and subjected to determination of the hepatic 4 - hydroxyproline content, which confirmed the hepatic fibrotic severity. Results : The serum concentrations of propranolol at 0.5, 1, 2 and 4 hours were significantly increased in CC1q-treated rats (p$lt;0.01). In proportion to the duration of CC4 treatment, Co and AUC were significantly increased, and Vdss and CLp were significantly decreased (p$lt;0.001). But MRT and t1/2(β) were not significantly changed. The hepatic 4 -hydroxyproline content was gradually increased in CC4-treated rats (p$lt;0.001). Conclusion - Gradual changes in pharmacokinetic parameters of propranolol were seen to be dependent on the hepatic fibrotic severity. We suggest that gradual dosage modification, according to their hepatic fibrotic severity, is necessary for many drugs administered to patients with chronic liver disease.(Korean J Hepatol 2001;7:181-188)

      • 액체로켓엔진의 성능 민감도 해석

        조원국(Won Kook Cho),남창호(Chang Ho Nam),박순영(Soon Young Park),김철웅(Chul Woong Kim) 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.11

        A sensitivity analysis of the liquid rocket engine has been made. A mode analysis program is used to predict the performance change due to the variation of rocket engine operating environment. The propellant supply pressure and density are the major variables of the operating condition. The material properties of the turbine driving gas is assumed as the function of mixture ratio. The discrepancies of performance change between constant turbine driving gas properties and variable properties are greater for the case of fuel pump inlet pressure change than the oxidizer pump inlet pressure change.

      • KCI등재후보

        광조사 강도가 복합레진의 중합반응속도에 미치는 영향에 관한 실시간 체적측정법을 이용한 연구

        라성호,이인복,김창근,조병훈,이광원,손호현 大韓齒科保存學會 2002 Restorative Dentistry & Endodontics Vol.27 No.2

        Objectives The aim of this study is to evaluate the effect of light intensity variation on the polymerization rate of composite resin using IB system (the experimental equipment designed by DR. IB Lee) by which real-time volumetric change of composite can be measured. Methods Three commercial composite resins [Z100(Z!), AeliteFil(AF), SureFil(SF)] were photopolymerized with Variable Intensity Polymerizer unit (Bisco, U.S.A.) under the variable light intensity (75/150/225/300/375/450mW^2) during 20 sec. Polymerization shrinkage of samples was detected continuously by IB system during 110 sec and the rate of polymerization shrinkage was obtained by its shrinkage data. Peak time(P.T.) showing the maximum rate of polymerization shrinkage was used to compare the polymerization rate. Results Peak time decreased with increasing light intensity(p<0.05). Maximum rate of polymerization shrinkage increased with increasing light intensity(p<0.05). Statistical analysis revealed a significant positive correlation between peak time and inverse square root of the light intensity (AF:R=0.965, Z1:R=0.974, SF:R=0.927). Statistical analysis revealed a significant negative correlation between the maximum rate of polymerization shrinkage and peak time(AF:R=-0.933, Z1:R=-0.892, SF:R=-0.883), and a significant positive correlation between the maximum rate of polymerization shrinkage and square root of the light intensity(AF:R=0.988, Z1:R=0.974, SF:R=0.946). Discussion and Conclusions The polymerization rate of composite resins used in this study was proportional to the square root of light intensity. Maximum rate of polymerization shrinkage as well as peak time can be used to compare the polymerization rate. Real-time volume method using IB system can be a simple, alternative method to obtain the polymerization rate of composite resins.

      • SCISCIESCOPUSKCI등재

        Carburization of Iron Using CO-H₂ Gas Mixture

        Hwang, Ho-Sun,Chung, Uoo-Chang,Chung, Won-Sub,Cho, Young-Rae,Jung, Byong-Ho,Martin G.P. 대한금속재료학회 2004 METALS AND MATERIALS International Vol.10 No.1

        Iron carbides formed on the surface of iron and iron oxide samples at 640℃ in a gas mixture of CO-H₂ were characterized by scanning electron microscopy (SEM), MGssbauer spectroscopy, X-ray diffraction patterns (XRD), and by measuring mass change. The Fe₃C amount of the samples has been quantitatively evaluated by the weight change during carburization. While Fe₂O₃ powder was mostly completed to Fe₃C in the early stage, within 5 min after reduction reactions, the conversion of Fe powder sample to Fe₃C (iron carbide) was almost finished after 10 min. The carburization rate of a Fe sheet was very slow and intermediate products (Fe₂C, Fe₃C₂) were observed. This phenomenon is largely due to the difficulty of carbon diffusion into its dense surface. It was found that the carburization rate was affected by change of surface conditions and surface area by reduction, degradation, and cracks at high temperature. This study should help provide a fundamental understanding of carburization in the field of iron-making and suggest a direction for its further development.

      • KCI등재후보

        위용종의 내시경적 생검과 내시경적 절제술 후 병리학적 진단의 불일치

        윤원재 ( Won Jae Yoon ),이동호 ( Dong Ho Lee ),이국래 ( Kook Lae Lee ),장동경 ( Dong Kyung Chang ),김병관 ( Byeong Gwan Kim ),김지원 ( Ji Won Kim ),정지봉 ( Ji Bong Jeong ),김나영 ( Na Young Kim ),김진욱 ( Jin Wook Kim ),황진혁 ( 대한내과학회 2005 대한내과학회지 Vol.69 No.5

        목적 : 위용종이란 위의 내강으로 돌출한 종괴를 의미한다. 거의 90%에서 조직학적으로 과형성 용종이며 이러한 경우 암으로의 진행은 매우 적은 것으로 알려져 있다. 그러나 위선종은 일부에서 국소적으로 암성 병변을 동반하거나, 동반하고 있지 않더라도 시간이 지남에 따라 암으로 진행하는 것으로 알려져 있다. 그러나 내시경적 겸자 생검과 전체 병변의 절제 후 조직 소견에서는 차이가 있는 것으로 알려져 있다. 저자들은 내시경검사에서 위용종이 발견된 후 내시경적 절제술을 시행받은 74명의 환자, 85예의 위용종을 대상으로 임상적 및 병리학적 특성을 알아보고 겸자 생검과 내시경적 절제술 후 병리학적 진단의 불일치를 알아보고자 하였다. 방법 : 1996년 4월부터 2003년 2월까지 내시경검사에서 위용종이 발견된 후 내시경적 생검과 내시경적 절제술 후 조직학적 진단이 모두 이루어진 74명의 환자를 대상으로 내시경 사진, 의무 기록 및 병리 기록을 분석하였다. 결과 : 74명의 환자에서 총 85개의 용종을 관찰할 수 있었다. 위용종은 전정부에서 가장 호발하였으며(58.8%) 그 다음으로는 체하부(18.8%)에 호발하였다. 내시경적 겸자 생검에서 관상 선종은 48.2%, 과형성 용종은 30.6%, 염증성 용종은 15.3%, 위저선 용종은 2.4%, 이형성증은 2.4%, 관상융모 선종은 1.1%였다. 내시경적 절제술 후 조직학적 검사상 관상 선종은 45.9%, 과형성 용종은 31.8%, 염증성 용종은 9.4%, 과오종은 3.5%, 위저선 용종은 2.4%, 관상융모 선종은 2.4%, 선암은 2.4%, 이형성증은 1.1%, 점막 위지방종증은 1.1%였다. 내시경적 겸자 생검 결과와 내시경적 절제술 후 조직학적 진단의 불일치율은 27.1%였다. 용종의 크기에 따른 진단 일치율의 차이는 없었다(p>0.05). 결론 : 위용종의 겸자 생검과 내시경적 절제술 후 조직검사 소견은 차이가 있을 수 있다. 용종의 크기는 진단 일치율에 영향을 미치지 못했다. 따라서 특히 선종이 의심되는 경우에는 크기에 상관없이 내시경적 절제술을 통한 전체 병변의 조직검사가 필요할 것으로 생각된다. Background : Gastric polyp is a descriptive term referring to mucosal prominence that protrudes beyond the flat lining of the stomach. Almost 90% of gastric polyps are hyperplastic polyps. Adenomatous polyps may contain focal carcinomatous foci or undergo carcinomatous changes. It is known that there is some degree of discordance between the results of endoscopic forceps biopsy and pathology of resected specimens. The aim of this study was to investigate the discordance in pathologic findings between endoscopic forceps biopsy and endoscopic resection specimen of gastric polyps. Methods : We reviewed endoscopic photographs and medical records of the patients who underwent endoscopic resection from April, 1996 through February, 2003. Results : A total of 85 cases of gastric polyps from 74 patients were reviewed. Male-to-female ratio was 1:1.96. Mean age was 59.9±10.8 years. Multiple polyps were observed in 10.8%. Gastric polyps occurred in the antrum most frequently (58.8%). Pathology results on resected specimens were as follows: tubular adenoma 45.9%, hyperplastic polyp 31.8%, inflammatory polyp 9.4%, hamartoma 3.5%, fundic gland polyp 2.4%, tubulovillous adenoma 2.4%, adenocarcinoma 2.4%, dysplasia 1.1%, and mucosal pseudolipomatosis 1.1%. Discordance rate between endoscopic biopsy and pathology of resected specimens was 27.1%. There was no relationship between the size of the polyp and concordance rate. Conclusions : There was considerable discordance in pathologic findings between endoscopic forceps biopsy and resected specimens. Approaches to review the histology of an entire polyp should be performed, especially when an adenoma is suspected.(Korean J Med 69:481-486, 2005)

      • 化卉의 消費形態에 관한 硏究

        崔圭晧,裵相源,金昶佑 全北大學校 1995 論文集 Vol.39 No.-

        The purpose of this survey is to investigate and analize the status of flower consumption by city households so that it can provide basic materials for the development of horticulture industry. For this purpose, one thousand housewives were questioned living in six large cities : Seoul, Pusan, Taegu, Inchon, Kwangju and Taejon. The results of the analysis are as follows; 1. The most favorite cut flowers by season were rose, carnation and freesias in spring: roses and gypsophila paniculate in summer : chrysanthermum in autumn : gypsophila paniculate, roses chrysanthemums and lilies in winter. 2. The uses of cut flowers was mostly for gifts(58.4%), and that of pot flowers was mostly for home decoration. 3. flower shops were the most popular place for buying cut flowers(59.5%), followed by wholesale markets(22.5%) and street stalls(16.2%). In the case of pot flower, wholesale markets were the most favorite place(32.4%), street stalls(27.9%), flower shops(24.8%), and farm houses(11.9%). The survey showed that consumers frequent a shopping place because of 'easy accessibility', and 'various varieties in stock' in the case of cut flowers and, in that of pot flowers, 'easy accessibility' and 'low price' were the main resons in the case of pot flowers. 4. The purchase frequency rate by seson for cut flowers was that 'regardless of season' was 58.1% and 'spring', 28.9%. For pot flowers, 'spring' 58.9% and 'regardless of season' 33.6%. For the day of the week cut flowers were bought most open, Saturday came first with 34.2%, Monday and Sunday followed with 27.0% and 15.5% respectively. On the other hand, Sunday came first with 42.3%, Saturday(32.5%) and Monday(8.3%) took the second and third place respectively for pot flowers When it came to the purchase time of the day for cut flowers, 31.8% of the respondents bought then between ten and noon and 21.8% between four and six in the afternoon. 5. concerning the average amount of money spent at one time for cut flowers, 33.3% of the respondents said 3,000won to 5,000won and 23.2% replied 5,000won to 10,000won. While 36.8% answered that they paid 5,000won to 10,000won and 23.5% said 3,000won to 5,000won for a pot flowers. 6. Relating to the demand of flower stores, 28.8% wanted 'low price' : 27.9%. requested 'clear markings of the prices' : and 26.4%, wanted 'abundant commodities'

      • SCOPUSKCI등재

        출산에 따른 그레이브스병의 재발 및 관련이자

        임창훈,최현아,한승석,김해성,이창욱,정호연,한기옥,장학철,박원근,윤현구,한인권 대한내분비학회 2002 Endocrinology and metabolism Vol.17 No.2

        Background: Pregnancy affects the course of Graves' Disease (GD), and patients who initially maintain euthyroid function into their middle trimester with minimum doses of antithyroid drugs become exacerbated after delivery. Even patients who are completely cured, requiring no treatment during pregnancy, can relapse after delivery. In this study, we examined the postpartum changes in the thyroid functions of patients with GD, and attempted to determine the factors contributing to these changes. Methods: The study subjects were recruited from pregnant women visiting our outpatient clinic for routine prenatal evaluations. 45 women previously diagnosed with GD, who had been treated and cured with hyperthyroidism, and were no longer taking any thyroid medications, were evaluated for 1 year post delivery. Results: Among 45 patients, 20 (44.4%) developed thyroid disorders following delivery. Postpartum thyroiditis (PPT) developed in 8 patients (17.8%), and GD developed in 12 (26.0%). The onset of the PPT disease 3.1 ± 1.4 months following delivery, which was significantly earlier than the 6.7 ± 2.7 months required for the post delivery onset of GD (p=0.003). The TBII values, measured during the thyrotoxic state in each womaen, were negative in women with PPT and positive in 71.4% of women with GD (p=0.030). The duration of treatment for hyperthyroidism prior or pregnancy, the number of recurrences, and the time interval without treatment, were not associated with the development of postpartum thyroid disorders. Whereas, the mean number of past pregnancies for women who developed PPT was 3.9 ± 2.1, and was significantly higher than the 2.2 ± 1.7 for women developing no thyroid dysfunctions (p=0.044). In 13 women their initial onset of GD occurred within one year postpartum, 7 (53.8%) having had a recurrence, which was significantly higher than in women whose disease onset occurred unrelated to delivery (5 of 32 women: 15.6%). Conclusion: Women with GD developed postpartum thyroid dysfunctions in 44.4% of cases. Women whose initial disease onset occurred within one year postpartum had higher recurrences of GD, and women who developed PPT had a history of higher gravidity compared to the euthyroid women postpartum. Therefore, if women with GD develop postpartum thyroid dysfunctions, the diagnosis should be made, and a treatment modality planned, following careful considerations of the patients' past obstetric history, changes in clinical manifestations and the TBII values

      • SCIESCOPUS

        Ischemia-Related Changes in Galanin Expression in the Dentate Hilar Region after Transient Forebrain Ischemia in Gerbils

        LEE, Hyeon Yong,HWANG, In Koo,KIM, Dae Ho,KIM, Jung Hwa,KIM, Chang Ho,LIM, Beong Ou,KANG, Tae-Cheon,BANG, Kyung Hwan,SEONG, Nak Sul,LEE, Hak Ju,KIM, Jong Dai,WON, Moo Ho Japanese Association for Laboratory Animal Science 2005 EXPERIMENTAL ANIMALS Vol.54 No.1

        <P>Although galanin (GAL) protects hippocampal neurons from ischemic damage, no study has examined ischemia-related changes in endogenous GAL in the hippocampal dentate gyrus. We investigated the chronological changes of GAL, well-known as the potassium channel opener, expression in the dentate gyrus at various times after 5 min of transient forebrain ischemia in gerbils. A few GAL-immunoreactive (IR) neurons were found in the polymorphic layer of the sham-operated group. Three hours after ischemia-reperfusion, the pattern of GAL immunoreactivity was similar to that of the sham-operated group and the number of GAL-IR neurons and immunoreactivity were highest 12 h after ischemic insult. At this time, GAL-IR neurons in the polymorphic layer showed strong GAL immunoreactivity. Thereafter, GAL-IR neurons and immunoreactivity significantly decreased in the dentate hilar region. Four days after ischemic insult, GAL-IR neurons were not detectable. In addition, the results of a Western blot study showed a pattern of GAL expression similar to the immunohistochemical changes. GAL protein content also was highest 12 h after ischemia. In conclusion, the increased expression of endogenous GAL in the dentate gyrus after ischemia is related to response to the ischemic damage.</P>

      • HPV에 감염된 자궁경부 상피세포의 Keratin 아형 변화에 관한 연구

        기근홍,이영미,장원재,임용,임성철,김창원,전호종 조선대학교 1994 The Medical Journal of Chosun University Vol.19 No.2

        The human papillomavirus (HPV) are wide spread in the world, causing proliferation of epidermal and mucosal surface. Certain papillomaviral types are oncogenic in vivo and in vitro. HPV DNA has been detected in most of cervical lesions such as condyloma acuminata, dysplasias, and invasive carcinomas. The materials for this study consisted of 5 dysplasias. 5 squamous cell carcinomas, and 5 exocervix for control, that resected for definite treatment of uterine disease at Chosen University Hospital from January, 1991 to December, 1993. All cases were performed of in situ hybridization for HPV DNA type 6/11, 16, and 18. And also immununohistochemical stain for panel of monoclonal cytokeratin (CK) antibodies were done. The result obtained is as fallows : 1. HPV DNA type 6/11 are detected in all dysplasias. HPV DNA type 16 and 18 are detected in squamous cell carcinomas. 2. Stratifed squamous epithelium of exocervix are positive staining for CK 1, CK 5/6, CK 8, CK 13, CK 14, and CK 19. HPV DNA type 6/11 infected cells are positive for CK 1, CK 13, CK 14, CK 17, CK 18, and CK 19. HPV DNA type 16/18 infected cells are positive for CK 1, CK 5/6, CK 10, CK 13, CK 14, CK 17, CK 18, and CK 19. In conclusion, HPV infection of uterine cervix is associated with change of normal cytokeratin expression pattern. Dysplastic cells are changed of CK 5/6, CK 8, CK 17 and CK18. Squamous cell carcinoma cells are changed of CK 8, CK 17, and CK 18.

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼