중증 근무력증치료를 위한 광범위흉선절제술의 효과

김인광 대한흉부심장혈관외과학회 1995 Journal of Chest Surgery (J Chest Surg) Vol.28 No.9

Thymectomy has played a central role in the management of myasthenia gravis. Although both the etiology of myasthenia gravis and the reason for improvement after thymectomy remain incompletely explained, complete removal of the thymus is the logical goal of surgical treatment for this disease.From April 1989 to June 1994, maximal thymectomy was performed for 19 cases of myasthenia gravis at Chonnam National University Hospital. The results were as follows:1.Among the 19 cases, male-to-female ratio was 1:1.4, the age ranged 13 years to 71 years, and a diphasic presentation appeared with a peak in young females and a second peak in elderly males;2.Five cases were classified by modified Osserman`s classification as Group I and Group IIa and 14 cases as Group IIb and Group IIc; 3.Histologic examination of the excised thymus glands revealed normality in 5 cases [26% , thymic hyperplasia in 4 [21% , benign thymoma in 8 [42% , and malignant thymoma in 2 [11% ;4.There was no operative mortalities but two deaths occurred during the follow-up periods due to myasthenic crisis and other causes;5.The clinical improvement and the complete remission rates were 85% and 32%, respectively;6.The clinical improvement and the complete remission rates were not so good in patients with thymomas, beeing 70% and 20%, respectively; and 7.Young women with hyperplasia of the thymic tissue tended to show the best response to thymectomy.

마이크로스트립 원형 편파 개구면-패치 $8\times8$ 배열 안테나의 특성

김인광,박위상 한국전자파학회 1999 한국전자파학회논문지 Vol.10 No.7

X 대역에서 동작하는 마이크로스트립 원형 편파 개구연-패치 $8\times8$ 배열 안테나의 방사 특성에 대한 연구가 수행되었다. 복사 소자는 접지변에 모서리가 잘린 정사각형 개구면과 그 안에 기울어진 패치로 구성했고, 접지변 의 반대편에서 마이크로스트립 라인으로 coupling 시켰다. 상호결합을 최소화 하고, gam을 최대화 하기 위하여 소자 간의 간격은 $0.8\lambda_0$로 선택하였다. 급전구조는 병렬 형태로 구성하여 각 소자에 4개의 Wilkinson 분배기와 2개의 T - junction 분배기를 거쳐 전력을 공급한다. $8\times8$ 배열 안테나를 lOGHz에서 측정한 결과directivity는 26.3 d dBi, gain은 22.2 dBi, axial ratio는 2.97 dB, side lobe level은 12.7 dB로 나타났다. 배열의 크기가 커짐에 따라 d directivity는 증가하는 반면 효율은 감소하는 것을 확인하였다. The radiation characteristics of a microstrip circularly-polarized aperture-patch $8\times8$ array antenna are investigated at X-band. The radiator consists of a truncated square aperture on the ground plane with an inclined rectangular patch inside, and it is coupled by a microstrip line on the opposite side of the ground. The element spacing of the array was chosen as $0.8\lambda_0$so as to minimize the mutual coupling and maximize the gain. A corporate feed network was employed to distribute the power to each element through four Wilkinson and two T-junction dividers. Measurement results for the $8\times8$ array at 10 GHz showed a directivity of 26.3 dBi, a gain of 22.2 dBi, an axial ratio of 2.97 dB, and a side lobe level of -12.7dB. It was observed that when the array size increases, the directivity increases while the efficiency decreases.

혈액투석을 위한 동정맥루의 장기관찰 성적

김인광 대한흉부심장혈관외과학회 1994 Journal of Chest Surgery (J Chest Surg) Vol.27 No.9

From november, 1985 to May, 1993, 222 arteriovenous fistulae were made in 201 patients with chronic renal failure. Among them, a total of 183 arteriovenous fistulae in 173 patients were reviewed to evaluate the factors influencing patency rate of the vascular access. The results were revealed as follows: There were 102 men and 71 women,aged 10 to 76 years [mean = 45.7 years]. Sixteen patients of them had previous shunts. The procedures included establishment of 214 radiocephalic or brachioocephalic fistulae, 203 side to end, 9 side to side, 2 end to end, 2 autologous saphenous vein grafts, 6 Gore-Tex grafts. There were 28 early shunt failures[12%] due to use of 23 inadequate veins and 5 thrombosis.There were 32 late complications[14%]; 19 thrombosis, 4 aneurysm, 4 venous hypertension, 3 steal syndrome, 2 infections. There were 32 diabetic patients [17 %]. No significant differences in graft patency were noted between diabetic and nondiabetic individuals. There were no significant difference in graft patency between male and female. Overall shunt patency in 183 cases with chronic renal failure was 96% at I month, 95% at 3 months, 93% at I year, 91% at 2 years, 84% at 3 years, 56% at 5years.This Study showed that early postoperative thrombosis and diabetic vasculopathy were most causes of the vascular access failure and suggested that prevention of thrombi and well control of diabetes mellitus were most important to enhance patency rates of the vascular access.

고혈압에서 혈관 산화질소 합성 동위 효소 발현 변화

김인광,강대길,이종은,오봉석 大韓胸部外科學會 1999 Journal of Chest Surgery (J Chest Surg) Vol.32 No.2

FDTD 방법을 이용한 휴대폰 전파에 의한 인체 두부의 SAR 값 계산 ( SAR CAlculation in The Human Head for Cellular Phone Using The FDTD Method )

윤용섭,김인광,박위상 대한전자공학회 1998 대한전자공학회 학술대회 Vol.1998 No.5

휴대폰 전자파와 인체의 상호 영향 및 뼈 유사 물질 합성 연구

윤용섭,김인광,전중창,박위상 한국전자파학회 1999 한국전자파학회논문지 Vol.10 No.2

A simulation using the finite-difference time-domain method to analyze the electromagnetic interactions between a cellular phone and the human body was conducted, and a synthesis of a bone-equivalent material to make a human head phantom was performed. A test model of the cellular phone was fabricated to measure its reflection coefficient and radiation pattern in the free space. Various effects of the human body on the characteristics of the phone, such as input impedance, reflection coefficient, radiation pattern, and radiation efficiency are analyzed as the distance between the head and the phone antenna varies. When the phone was operated close to the head, the resonant frequency of the antenna decreased by up to 12%. With the output power of 0.6W, as long as the distance was larger than 30mm, the 1-g averaged peak SAR was below the ANSI/IEEE safety guideline, 1.6 W/kg. To synthesize the bone-equivalent material, an epoxy with hardener and a graphite powder were used as basis ingredients, and a small amount of a conducting epoxy was added to control the conductivity of the material. A material having a relative permittivity of 18.04 and a conductivity of 0.347, which are close to those of the bone at 850 MHz, was synthesized. 유한차분 시간영역 수치해석 기법을 사용하여 휴대폰과 인체 간의 전자파 결합 현상을 시율레이션하였고, 인체 두부의 모형을 제작하기 위한 생체 뼈 유사 물질의 합성에 관한 연구를 수행했다. 휴대폰 모형을 제작 하여 자유 공간에서 안테나 반사계수 및 복사 패턴을 측정하였다. 인체와 안테나 사이의 거리를 매개 변수로 하여 안테나의 입력 임피던스, 반사계수, 복사 패턴, 효율, 그리고 인체 두부의 전력 홉수량을 계산하였다. 인 체 근접 효과에 의하여 안테나 공진 주파수가 약 12 %까지 감소되었으며, 출력이 0.6W일 때, 두부와 안테나 사이의 거리가 30mm이상 떨어져 있을 경우, l-g 평균 최대 SAR가 ANSVIEEE 안전 기준인 1.6 W /kg 이 하로 계산되었다. 뼈 유사 물질의 합성에는 에폭시, 응고제, 그리고 흑연 분말을 기본 물질로 하고, 전도도를 제어하기 위해 소량의 전도성 에폭시를 첨가하였다. 850 MHz에서 비유전율이 18.04, 전도도가 0.347로서 생체 뼈의 특성에 매우 근접하는 시료가 합성되었음을 보였다.

신혈관성 및 DOCA - salt 고혈압 혈관에서 nitric oxise synthase 및 guanylate cyclase isozyme의 변화

최기철,김인광,강대길,안미라,김수완,김남호,이종원,강영준 대한신장학회 1997 춘계학술대회 초록집 Vol.1997 No.-

Behcet's 병을 동반한 Budd-Chiari 증후군 -1례 보고-

오봉석,김보영,김인광,O, Bong-Seok,Kim, Bo-Yeong,Kim, In-Gwang 대한흉부심장혈관외과학회 1996 Journal of Chest Surgery (J Chest Surg) Vol.29 No.2

A 34-year-old man was admitted to the hospital because of ascites, abdominal fullness. computed tomography and cavography revealed inferior vena cavil occlusion just above the hepatic vein and diagnosed as Budd-Chiari syndrome. conservative medical therapy failed to control the symptoms produced from both portal hypertension and versa caval stasis. Therefore, under extracorporeal circulation with moderate hypothermia and normal cardiac contraction, membranoto y and inferior vena casa venoplasty with Gore-tex (10mm) was performed. Postoperatively, physical examination revealed oral ulceration, subcutaneous thrombophlebitis, folliculitic lesions. uveitis And increased reactivity of the skin to needle punctures. 10 month later, superior vena ciiva obstruction symptom was found. Hehcet's disease was diagnosed. 34세 남자가 복수 및 복부 팽 만감을 주소로 입원하였다. 단층촬영 및 하대정맥 조영술상 간정맥 직상부의 하대 정맥폐색이 의심되는 Budd-Chiari 증후군으로 진단되었다. 대증요법으로 간문맥고혈압과 하대정맥폐색증상이 호전이 안되어, 체외순환, 중등도저체온 및 정 상심박동하에 폐색부위절제술 및 하대정맥성형술을 10mm인조혈관을 사용하여 시행하였다. 술후 환자는 구강및 피부와 이학적 검사상 구강궤양, 피하 혈전성 정맥염, 모낭염성 병변, 피부의 자극성 항진 및 포도막염이 관찰되었고 상대정맥 폐색증상이 병발하였으며 Behcet씨 병으로 진단되었다.