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      • KCI등재

        대퇴동맥을 통한 경피적 관동맥 중재시술 환자의 천자부위 지혈을 위한 Angioseal^(�) 사용과 고식적 용수 압박법의 비교 : 전향적 연구

        김용훈,권현철,김필호,안석진,유철웅,최진호,이상철,김준수,김덕경,전은석,이상훈,홍경표,박정의,서정돈 대한내과학회 2004 대한내과학회지 Vol.66 No.5

        목적 : 경피적 관동맥 중재술은 최근 양적 및 질적으로 급격한 발전을 보였지만 시술 시 천자부위의 혈관 합병증은 아직 해결해야 할 문제점이다. 저자들은 대퇴동맥을 통한 경피적 관동맥 중재술을 환자에게 천자부위 지혈을 위한 혈관폐쇄기구인 안지오실의 안전성과 유용성을 고식적인 용수 압박법과 비교 연구하고자 하였다. 방법 : 2002년 4월부터 2003년 5월 사이에 삼성서울병원 심장혈관센터에서 대퇴동맥을 통한 경피적 관동맥 중재술을 성공적으로 시행한 200명의 환자(안지오실 사용군: A군, 100명, 고식적 용수압박법 사용군 B군, 100명)를 대상으로 시술 후 주요 합병증 및 경한 합병증, 지혈 후 환자가 자리에 앉기까지의 시간, 보행개시 가능시간, 총 재원 기간과 시술 1주 후의 합병증을 전향적으로 조사하여 비교 연구하였다. 결론 : 두 군에서 연령, 성별, 기저질환, 심혈관 질환의 위험요소, 시술의 종류, 시술 중 사용한 헤파린의 양, clopidogrel의 양, ticlopidine의 양, 지혈 시 수축기와 확장기혈압, ACT (activated clotting time)는 차이가 없었다. A군이 B군에 비해 시술 후 자리에 앉기까지의 시간 (A군: 4.3±0.3시간, B군: 13.7±0.8시간, p=0.004) 및 보행개시까지의 시간(A군: 6.8±0.5시간, B군: 18.8±2.1시간, p=0.013)이 유의하게 짧았다. 시술 후 주요 합병증은 두군 모두에서 관찰되지 않았으며, 경한 합병증의 전체발생은 A군에서 유의하게 적었다(A군: 28명, B군: 19명, p=0.003). 반상출혈의 경우는 A군에서 유의하게 낮았지만(A군: 3명, B군: 12명, p=0.01), 혈종, 출혈의 발생은 두군간에 차이가 없었다. 총 재원기간에는 두 군간에 차이가 없었다(p=0.239). 시술 1주 후 경과관찰에서 주요합병증은 역시 두 군 모두에서 관찰되지 않았으며, 경한 합병증의 전체발생은 두 군에서 차이가 없었다(A군: 15명, B군: 13명 p=0.418), 반상출혈의 빈도는 차이가 없었지만 혈종의 발생은 A군에서 더 낮았다(A군: 2명, B군:6명, p=0.004). 두 군 모두에서 출혈은 발생하지 않았다. 결론 : 대퇴동맥을 통한 경피적 관동맥 중재술을 시행한 환자에서 안지오실의 사용은 고식적 용수 압박법에 비해 환자의 침상 안정시간을 줄여 조기 활동개시가 가능하게 하였으며 국소합병증의 위험도를 일부 낮추어, 시술에 따른 환자의 불편을 현저하게 감소시킬 수 있다고 할 수 있을 것으로 기대된다. Background : Although the number and the quality of percutaneous coronary intervention have been recently increased dramatically, the vascular complication at puncture site is still the major cause of patients' morbidity. We evaluated the safety and efficacy of newly of newly-developed collagen-based arterial closure device, Angioseal after transfemoral percuatenous coronary intervention. Methods : This study was designed as a prospective single center non-randomized comparative study. A total 200 patients undergoing transfemoral percutaneous coronary intervention were enrolled between April 2002 and May 2003. They were divided into two groups; Angioseal group (group A, n=100) and manual compression group (group B, n=100). The baseline clinical and angiographic characteristics were reviewed. The time to sit up, the time to ambulation, the duration of hospital stay, major and minor vascular puncture site complications were monitored. The patients were followed-up for 1 week after procedure by telephone. Results : The baseline clinical characteriwtics, clinical diagnosis, cardiocascular risk factors, typesof procedure, doses and numbers of anticoagulants were similar between two groups. The blood pressure and activated clotting time were also similar. The time to sit up (group A: 4.3±0.3 hours, group B: 13.7±0.8 hours, p=0.004) and the time to ambulation (group A: 6.8±0.5 hours, group B: 18.8±2.1 hours, p=0.013) were shorter in group A. No major vascular complications were noted. The incidence of hematoma and bleeding were not significantly different between two groups. The incidence of ecchymosis, however, was significantly lower in group A (group A:12%, group B: 3%, p=0.001) The duration of gospital stay was similar between groups. During 7 days of follow-up period incidence of hematoma was significantly lower in group A (p=0.004). Although the incidence of ecchymosis was not significantly different between two groups. Conclusion : The angioseal may be associated with earlier ambulation and less patients' morbidity with low incidence of local complication rate compared to manual compression after transfemoral percutaneous coronary intervention.

      • KCI등재

        갈륨합금과 고동 아말감 합금의 물리적 성질 비교

        김현철,이희주,허복 大韓齒科保存學會 1998 Restorative Dentistry & Endodontics Vol.23 No.1

        The purpose of this study was to compare the physical properties between high copper amalgam and gallium restorative material. In this study, the specimens for the 4 experimatal groups(Valiant, Valiant PhD, Gallium Alloy GF Ⅱ, Gallium Alloy GF Ⅱ triturated with some addition of alcohol) were prepared in the manner of which stated in ADA specification No. 1 for amalgam alloy. And then, measured and compared the value of compressive strength, creep, and dimensional change during hardening of each sample. The results were as follows: 1. In the compressive strength, the valiant-lathe cut type high copper amalgam-had the highest value of strength(p<0.05), and the Valiant PhD-admixed type high copper amalgam-showed the higher value of strength than the Gallium Alloy GF Ⅱ(p<0.05) but had no significant difference with Gallium Alloy GF Ⅱ triturated with some addition of alcohol(p>0.05). 2. In the creep, the Valiant PhD showed the highest value of creep(p<0.05), but there was no significant difference between Gallium Alloy GF Ⅱ and Valiant(p>0.05). 3. In the dimensional change during hardening, no two groups were significantly different at the 0.050 level. 4. There was no significant difference between Gallium Alloy GF Ⅱ and the same material which was triturated with some addition of alcohol(p>0.05).

      • KCI등재

        Enterococcus faecalis 추출물이 임파구의 IL-2, IL-4, TGF-β1분비에 미치는 영향에 관한 연구

        김현식,이우철,손원준,이상탁,김철호,임성삼 大韓齒科保存學會 2005 Restorative Dentistry & Endodontics Vol.30 No.1

        In order to examine the immunoresponse of host cells to Enterococcus faecalis, this in vitro study monitored the production of Interleukin-2 (IL-2), Interleukin-4 (IL-4) and Transforming growth factor-β1 (TGF-β1) in human lymphocytes. Lymphocytes were activated with PHA in the presence or abscence of sonicated extracts of E. Faecalis (SEF) and further incubated for 72 hours. The level of each cytokine was measured by ELISA. Data were analyzed with Kruskal-Wallis test and Mann-Whitney U test (P < 0.05). PHA-activated group did exhibit higher level of IL-2 and IL-4 than untreated control group. The levels of expression of both cytokines were significantly decreased following the treatment of high (25㎍/㎖) and medium concentration (12.5㎍/㎖) of SEF (P > 0.05) than those of PHA activated group. But low concentration (5㎍/㎖) of SEF showed th similar level of IL-2 and IL-4 production as those of PHA activated group. TGF-β1 was unaffected by SEF treatment. These results suggested that E. faecalis may suppress IL-2 and IL-4 production by lymphocytes and this could be one of possible factors why E. faecalis are found frequently in the teeth with failed endodontic treatment. 근관치료의 실패원인 중 중요한 세균으로 알려진 Enterococcus faecalis는 최근에 중요성이 더해지며 많은 연구들이 진행중이다. 여러가지 기전들이 보고되고 있으나 면역반응에 관한 연구는 거의 알려져 있지 않은 상태이다. 본 연구에서는 Enterococcus faecalis의 초음파 분쇄 추출물을 성인의 말초혈액으로부터 얻은 임파구에 적용시켜서 여기서 분비되는 interleukin-2, interleukin-4, transforming growth fater-β1의 농도를 Enzyme linked immunosorbent assay (ELISA)로 측정하여 비교, 평가하는 것을 목적으로 한다. E. faecalis를 적절한 조건에서 배양한 뒤 초음파 분쇄를 하여 추출물을 얻어냈다. 임파구는 건강한 성인의 말초혈액에서 추출하여 분리하였다. 임파구를 적절한 농도의 mitogen (Phytohemagglutinin: PHA)으로 자극시킨 뒤에 다양한 농도의 E. faecalis 초음파 추출물을 적용시키고 72시간 동안 배양하였다 ELISA를 이용하여 IL-2, IL-4,TGF-β1 의 농도를 측정하였다. 실험결과는 Kruskal-Wallis test, Man-Whitney rank sum test (p < 0.05)를 사용하여 통계처리 하였다. 실험결과 PHA로 처리한 군은 아무것도 처리하지 않은 군에 비해서 IL-2, IL-4의 수치가 유의성 있게 높았다 (p < 0.05). PHA로 처리한 군중에서 고농도와 중농도의 sonic extract of E. faecalis (SEF)로 처리한 군은 그렇지 않은 군에 비해서 IL-2 IL-4의 농도가 유의성 있게 낮았다 (p < 0.05). PHA로 처리한 군중에서 저농도의 SEF로 처리한 군은 그렇지 않은 군과 비교하여 유의할 만한 차이를 보이지 않았다.TGF-β1의 농도는 모든 군에서 유의할 만한 차이를 보이지 않았다 (p > 0.05). 따라서, E. faecalis의 추출물은 임파구의 IL-2, IL-4의 분비능력을 저하시킨다고 할 수 있다.

      • Mo¨nckeberg 중막 석회화로 인해 초기자궁내막암이 진행성 자궁내막암으로 판독되었던 1례

        김승만,배철성,김동훈,김정란,이현경,윤혜원 동국대학교 경주대학 1997 東國論集 Vol.16 No.1

        Mo¨nckeberg 중막 석회화는 크거나 중간크기의 근육성 동맥(large and medium-sized muscular arteries)의 중막(media)에 노화와 관련되어 퇴행성 과정인 윤상석회화가 특징적으로 나타나는 동맥경화증의 일종으로, 근본적으로 폐쇄성 죽상경화증(occlusive atherosclerosis)과는 다른 과정으로 동맥의 관강(lumen)을 막는 경우는 드물어 상대적으로 임상적 의의는 적거나 거의 없다. 저자들은 Mo¨nckeberg 중막 석회화때문에 초음파 및 컴퓨터 단층촬영에 의한 병기결정에 혼란을 초래하였던 초기 자궁내막암 1례를 경험하였기에 문헌고찰과 함께 보고하는 바이다. The Mo¨nckeberg medial calcification is aging change rather than disease entity. The Mo¨nckeberg medial calcification involve muscular arteries of limb, head, and genital track and cause fibrosis change associated with hyalinization and fine basophilic staining, suggesting early calcification with little or no clinical significance but is demonstrable on roentgenograms as regular and diffuse radiopaque shadow under intima. We experienced one case of mis-staging of early endometrial cancer due to the Mo¨nckeberg medial calcification therefore, we report this case with a brief review of the literature of the Mo¨nckeberg medial calcification.

      • S.D. Rats를 이용 1, 1-Dichloro-1-fluoroethane의 아민성 흡입독성 연구

        김현영,이성배,임철홍,김철우,점용현,한정희,전윤석,최수영,강대봉,이용묵 한국환경독성학회 2002 환경독성보건학회지 Vol.17 No.1

        There were no specific effects for test materials on Sprague-Dawley (S.D.) rats in clinical symptoms, amounts of food intakes, weight changes, laboratory findings, and pathology after whole body l, l-Dichloro-1 -fluoroethane (used as coolant, metal cleaner and solvents) exposure(0, 1,500, 3,000, and 6,000 ppm) for 13 weeks (6 hour/day, 5 days/week). However, the loss of capillary vessels in eyeball (pupil) was observed in a female rat among 6,000 ppm group. Though there was a tendency for MCHC (Mean Corpuscular Hemoglobin Concentration) in rat to be decreased (p<0.05), it was not regarded as abnormal because the values were within normal limits. In asthma-stimulation related evaluations, there was also a tendency for inflammatory cell counts in bronchoalveolar lavages to be increased. But it had no statistical significance, and also no dependency on sex and the exposed concentration. Based on this result, the non observed effect level (NOEL) induced by 1, 1-Dichloro-l -fluoroethene inhalation was evaluated in groups with 3,000 ppm below (S .D. Rats, 13 weeks). Finally, it was concluded that the short term exposal of 1, 1-Dichloro-l-fluoroethane is not considered as a asthma stimulant by inhalation despite of some study limitations such as test animals use and short-term exposure .

      • KCI등재

        ProTaper의 세가지 사용방식에 따른 성형능역 비교

        김소연,박정길,허복,김현철 大韓齒科保存學會 2005 Restorative Dentistry & Endodontics Vol.30 No.1

        이 연구의 목적은 만곡이 삼한 근관에서 ProTaper(R)를 수동으로 사용하는 방법, 엔진 구동으로 사용하는 방법, 그리고, 치관부는 엔진 구동으로 치근단부는 수동으로 사용하는 세 가지 방법의 근관 성형 능력을 비교하기 위한 것이다. 근관 길이가 170mm이고 근관 입구에서 10mm 떨어진 부위에서 만곡이 시작되며 평균 40도의 단일 만곡을 가지는 투명한 레진 블락 30개를 사용하였다. 각 군당 10개의 레진 블락을 사용하였으며, 수동형 ProTaper(R)로 전체근관을 성형한 군형 M군, 엔진 구동형 ProTaper(R)로 전체근관을 성형한 군을 R군, 근단부는 수동형 ProTaper(R)를, 치관부는 엔진 구동형 ProTaper(R)를 사용하여 성형한 군을 H군으로 하였다. 각각의 블락을 성형하고 각 군별 근관 성형시간을 기록하였다. 근관 성형전과 후의 이미지를 중첩하여 근단공으로부터의 수직 이동 거리 1, 2, 3, 4, 5 그리고 6 mm 위치에서 수평선을 긋고 총 근관폭경, 근관 만곡 내외측 삭제량, 근관의 변위, 중심 이동률을 평가하여 다음과 같은 결론을 얻었다. 1. 근관 성형시간은 R군, H군, M군 순으로 짧았고, 세 군 사이에는 유의한 차이가 있었다(p < 0.05). 2. R군이 전체적으로 삭제량이 많은 경향을 보였으나, 1, 3 mm를 제외하고는 차이가 없었다(p > 0.05). 3. 만곡내측 삭제량에 있어서는 1 mm 지점에서는 R군이, 6 mm 지점에서는 H군이 컸지만 (p < 0.05), 나머지 지점에서는 차이가 없었다. 만곡외측 삭제량은 1 mm 지점에서만 R군이 컸다 (p > 0.05). 4. H군, R군은 1, 2, 3 mm 지점, M군은 1, 2 mm 지점에서 만곡외측으로의 변위를 보였고, 그 외의 지점에서는 내측변위를 보였다. 각 군 간의 변위차이는 6 mm 지점에서 H군이 컸다(p < 0.05). 5. 근관의 중심 이동률은 6 mm 지점에서 H군이 R군에 비해 유의하게 컸지만 다른 모든 위치에서는 차이가 없었다(p < 0.05). 본 실험결과를 토대로 할 때, 각 평가 항목에서 측정 위치에 따라 약간씩 차이가 있었으나, 중심 이동률은 대부분의 위치에서 유의한 차이가 없었다. 따라서 만곡 근관을 성형시에는 세 가지 방법 중 어느 것이 더 유용하다고 보기 어렵다고 판단된다. The purpose of this study was to compare the shaping ability of the three ProTaper instrumentation techniques in simulated canals. Thirty resin blocks were divided into 3 groups with 10 canals each. Each group was instrumented with manual ProTaper (Group M), rotary ProTaper (Group R), and hybrid technique (Group H). Canal preparation time was recorded. The images of pre- and post-instrumented root canals were scanned and superimposed. The amounts of canal deviation, total canal width, inner canal width, outer canal width and centering ratio were measured at apical 1, 2, 3, 4, 5 and 6 mm levels. 1. Canal preparation time was the shortest in R group (p <0.05). 2. The amounts of total canal width in R group was generally larger than the other groups, but no significant differences were observed except at the 1, 3 mm levels (p ) 0.05). 3. The amounts of inner canal width in R group was larger than M group at the 1 mm level and H group was larger than R group at the 6 mm level (p < 0.05). The amounts of outer canal width in R group was larger than H group only at the 1 mm level (p <0.05). 4. The direction of canal deviation in H, R group at the 1, 2, 3 mm levels was outward and that in M group at the I, 2 mm levels was inward. The amounts of canal deviation in H group was larger than R group at the 6 mm level (p <0.05). 5. The amounts of centering ratio in H group was larger than R group at the 6 mm level (p <0.05).

      • KCI등재

        무속적 상상력과 초논리성 연구 : 오태석의 <백마강 달밤에>를 중심으로

        김현철 고려대학교 한국학연구소 2001 한국학연구 Vol.14 No.-

        In this study, I tried examining how Shaman imagination was dramatized in Oh Tae-Suk's work, 〈In a Moonlight Night of Baekma River〉. Modernizing traditional plays has become a contemporary dramatists' topic of importance, Most dramatists devote themselves to the work of modernizing a Shaman ritual of Gut to seek out a Korean archetype. Since Gut can always make past and present, reality and illusion, and this world and the other world harmonized spontaneously in the same space and time, it has been thought of very attractive. Especially, in that its mechanism is a course that leads conflict and opposition to reconciliation, Gut has a greater correlation to a play. This element characteristics is introduced very actively in 〈In a Moonlight Night of Beakma River〉. first, on the aspect of the plot, "Eunsan Byulsin - Gut"and "Bari Princess"offer the frame for its composition. Especially, 'Sunan',a dramatic character, has a similarity to Bari Princess. Next, on the aspect of content, I looked into "Coexistence of ordinary feature and ritual one"and "Madness and Super-logicality"In "Coexistence of ordinary feature and ritual one", Oh describes that the dramatic principle of 〈In a Moonlight Night of Baekma River〉is based on a Shaman imagination, that is, a harmony of space and time. Particulary, in "Scene on going on the stone bridge"in the latter half, it is shown that a real figure and a mythic figure are joined together without any difference. This ritual is also connected to consciousness that the dead are closely related to the living. "Madness and Super-logicality"gives and account of 〈In a Moonlight Night of Beakma River〉's ending part, where the mechanism of Gut is made use of. Gut has a structure that conflict and opposition end in an amicable settlement. The Motif of King Eu-je who was reincarnated as a school captain at the in the conclusion, is a part which presents a little logical jump. Farther prudential link should have been made so that the work could have been formed as one preserved super-logicality, escaping illogicality. In this way, Gut is a treasury from which you can extract rich imagnation and new devices on a stage. It, however, can result in another problem, an excess of subjectivity, if the source itself depends on just imgaination. That is, you ought to bear logical linkage based on free imagination in mind.

      • 사회정의의 개념과 의의

        김현철 이화여자대학교 2004 法學論集 Vol.9 No.1

        The reason why the concept of social justice is ambiguous that Because the concept of 'social' is ambiguous. Moreover the concept of 'justice' is ambiguous, too. The concept of 'social' is relevant to 'social problems'. Social problems such as unemployment, aging, disease, hunger, poverty and so forth were occurred since 19th century, because of classical capitalism. The concept of 'justic' is developed in historical context. Through ancient greece, roman empire, medieval period and modern period, the concept of justice entails the property of supremacy over the other values. This supremacy of justice is the strong reason that the give-up of the concept of justice is unpermissible. Thus social justice has the property of supremacy. And contemporary social justice is relevant to contemporary social problems. Furthermore, social justice considers particular issues in Korea, such as discrimination, gap of economic position, human rights, poverty and so forth. In this meaning, equality in law and human rights are the important elements to understand social justice.

      • SD Rats를 이용 1-hexene의 흡입독성 연구

        김현영,임철홍,정용현,이권섭,이성배,이준연,한정희,전윤석,이용묵 한국환경독성학회 2001 환경독성보건학회지 Vol.16 No.4

        The purpose of this study was to investigate the acute (4 hours) and repeated-dose (6 hours a day, 5 days a week, 4 weeks) toxic effects of I -hexene on Sprague- Dawley (SD) rats which were treated by inhalation. The results were as follows; I. The median lethal concentration (LC_(50)) was estimated 52,694 ppm (confidence limit 95%; 49,494~55,447 ppm) in acute inhalation. Abnormal clinical signs related to the l-Hexene were not observed with the acute inhalation dose. Gross findings of necropsy revealed on evidence of specific toxicity related to the 1-hexene, II. By repeated inhalation exposure the body weight of male were more or less reduced by the dose of 2,500 ppm and 5,000 ppm compared with control group. However there were no significant variation hematology and blood biochemistry for the exposed rats compared with the control rats. Abnormal clinical signs and gross findings of necropsy related to the 1-hexene were not shown. In conclusion when we exposed I-hexene to SD rats for 4 weeks, 5 days per week, 6 hours per day, the Lowest observed effect level (LOEL) was over 2,500 ppm and Non observed effect level (NOEL) was below 500 ppm.

      • KCI등재

        세가지 니켈 티타늄 파일의 휨과 비틀림 조건에서의 응력 분포에 관한 3차원 유한요소 연구

        김태오,이찬주,김병민,박정길,허복,김현철 大韓齒科保存學會 2008 Restorative Dentistry & Endodontics Vol.33 No.4

        이 연구의 목적은 세가지 니켈-티타늄 파일의 휨과 회전 조건 하에서의 응력 분포를 유한요소 모형을 이용하여 비교하는 것이다. ProFile .06/#30, ProTaper와 ProTaper Universal의 F3파일을 마이크로컴퓨터 단층촬영을 하고 reverse engineering을 통하여 세 니켈 티타늄 파일의 구조를 얻고 삼차원 유한요소모형을 제작하였다. 니켈 티타늄 합금의 비선형적인 물리적 성질을 반영하고 ABAQUS 프로그램을 이용하여 휨과 회전 조건 하에서의 기계적인 움직임을 수학적으로 예측 분석하였다. U-형태의 단면 구조를 가진 ProFile이 모형 가운데 가장 좋은 휨 성질을 나타냈다. 동일한 휨량 조건에서는 볼록한 삼각형 단면의 ProTaper가 다른모형보다 많은 힘을 필요로 하였으며, 반면에 가장 높은 von Mises 응력은 ProTaper Universal의 단면에서 움푹 파인 부위에 집중되었다. ProFile 모형은 동일한 크기의 회전력에 대해 가장 큰 응력 집중을 U-형 구 부위에 나타냈다. ProTaper 모형은 다른 모형에 비해 동일량을 비틀기 위해 더 많은 힘을 필요로 하였으며, 반면에 동량의 비틀림에서는 가장 높은 von Mises 응력이 ProTaper Universal의 단면에서 움푹 파인 부위에 집중되었다. Flexibility and fracture properties determine the performance of NiTi rotary instruments. The purpose of this study was to evaluate how geometrical differences between three NiTi instruments affect the deformation and stress distributions under bending and torsional conditions using finite element analysis. Three NiTi files (ProFile .06 / #30, F3 of ProTaper and ProTaper Universal) were scanned using a Micro-CT. The obtained structural geometries were meshed with linear, eight-noded hexahedral elements. The mechanical behavior (deformation and von Mises equivalent stress) of the three endodontic instruments were analyzed under four bending and rotational conditions using ABAQUS finite element analysis software. The nonlinear mechanical behavior of the NiTi was taken into account. The U-shaped cross sectional geometry of ProFile showed the highest flexibility of the three file models. The ProTaper, which has a convex triangular cross-section, was the most stiff file model. For the same deflection, the ProTaper required more force to reach the same deflection as the other models, and needed more torque than other models for the same amount of rotation. The highest von Mises stress value was found at the groove area in the cross-section of the ProTaper Universal. Under torsion, all files showed highest stresses at their groove area. The ProFile showed highest von Mises stress value under the same torsional moment while the ProTaper Universal showed the highest value under same rotational angle.

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