소뇌에 발생한 과립구성 육종 : 증례보고

윤승환,변진수,홍순기,김헌주,한용표,양재승,조미연 대한신경외과학회 1995 Journal of Korean neurosurgical society Vol.24 No.8

Granulocytic sarcoma, a rare extramedullary solid tumor arising from early myeloid precursors, is capable of invading the meninges or the brain parenchyma. The tumor may occur during or after the onset of systemic myelogenous leukemia. On rare occasions, the tumor may evolve before the onset of systemic myelogenous leukemia. Children are affected more often than adults, but sex is not related. Although no definite target area of the brain can be demonstrated, there may be some predilection of the tumor for the posterior fossa. The authors report a case of 4-year-old-boy with granulocytic sarcoma occuring in the posterior fossa presenting with gait disturbance and torticollis. The patient was treated by surgical removal of the tumor, thereby avoiding the potentially lethal complication of a posterior fassa mass. This rare case is reported together a review of the literature.

Ethylene Glycol 식이하 백서 신장내 수산칼슘침착에 대한 성 호르몬의 영향

윤승환,문영태,김미경 大韓泌尿器科學會 2001 Korean Journal of Urology Vol.42 No.5

뇌실질내에 발생한 Sparganosis의 임상적 분석

윤승환,허철,변진수,홍순기,김헌주,한용표 대한신경외과학회 1994 Journal of Korean neurosurgical society Vol.23 No.3

The tape-worm spirometra mansonoides infests man world-widely, particularly in Asian countries with rare involvement of the central nervous system. Recently, the authors have experienced 7 cases of cerebral sparganosis, and reviewed their clinical manifestation, radiographic findings, and follow-up results. The cerebral sparganosis manifests headache, seizure or hemiparesis. Most of patient had episodes of eating frogs or snakes. The brain CT scan showed low density area with ipsilateral ventricular dilatation. Enzyme linked immunosorbent assay(ELISA) test showed positive response to serum and cerebrospinal fluid. The best treatment for cerebral sparganosis mansoni is surgical removal, fron which we confirmed 4(17%) cases of live worms in operative and patholgic findings, and most of the seizure disappeared or decreased after operation.

TFC을 이용한 하부 요추골에서 후방 추체간 융합술

윤승환,조준,문창택,장상근 건국대학교 의과학연구소 2000 건국의과학학술지 Vol.10 No.-

To determine which factors influence the successful results in the patients who underwent lumbar arthrodesis with TFC(threaded fusion cage) at L34 to L5S1 intervertebral space. 20 subjects were analysed in retrospective method. Between January 1997 and April 1998, interbody fusion with TFC was undergone on 20 patients, and among them, 19 patients(95% ) were confirmed to have bone fusion at 12 months after operation. All patients were classified into group A(satisfactory results) and group B(unsatisfactory results) according to comprehensive low back questionnaires from their answer. They were checked with reference to intervertebral disc height and scoliotic, and lordotic angle with Cobb's method in the anterioposterior and lateral lumbar spine films before/after operation, and TFC diameter and length were categorized. In group A, 11 cases(55%) of "excellent" results and 5 cases(25%) of "good" results were included. In group B, 2 cases(10%) of "fair" results and 2 cases (10%) of "poor" results were included. In the lateral projection of group A and B. the mean preoperative disc height were 9.88±2.69mm and 10.45±2.39mm. Twelve months after operation, the mean disc height of group A was significantly increased to 14.11±2.14mm, but that in group B was not significantly increased only to 11.50±2.52mm. Preoperatively, the measured scoliotic and lordotic angles between L1 and S1 by Cobb's method were similar in both groups, being 4.18±3.58 and 26.75±6.64 degree in the group A, 3.50±2.65 and 33.25± 13.10 degreee in the group B. Twelve months after operation, the angles for group A were significantly improved to 0 and 48.13±11.83 degree, but in group B, not changed into 4.50±4.79 and 33.75±10.31 degree. The mean diameter and length of TFC in group A were, in each, 15.62± 1.09mm and 24.44±2.39mm but, 12.50±1.00mm and 21.00±0.00mm in those of group B. For successful results after TFC interbody fusion in the lower lumbar spine, recovery of narrow disc space, scoliosis, lordosis accompanied by solid arthrodesis were necessary. The authors propose that relatively larger-sized TFC should be profitable for those cases.

평면광도파로용 저광굴절율 바이오폴리머 제조

윤승환,김종욱,김경천,이상매 한국통신학회 2009 한국통신학회 기타 간행물 Vol.2009 No.12

기술혁신형 중소기업의 혁신역량과 수출성과:유연성의 조절효과

윤승환,안세화 한독경상학회 2022 經商論叢 Vol.40 No.2

This study explores new factors affecting the causal relationship between innovation capabilities and the export performance of technological innovation-type SMEs. In a rapidly changing environment in the global market, even SMEs with innovative capabilities may differ from company to company in how they actually respond to changes in external conditions. Therefore, the purpose of this study is to investigate the gap that can not be explained only by a single and direct relationship between innovation capabilities and export performance. To this end, a research model was designed, composed of export performance as a dependent variable, technological innovation capabilities and marketing innovation capabilities as independent variables, and organizational flexibility as a moderating variable. In order to estimate this model, data were collected for INNOBIZ companies, and multiple regression analysis and moderating regression analysis were conducted. As a result, it was found that both technological innovation capabilities and marketing innovation capabilities have a positive effect on export performance even in the context of technological innovation-type SMEs. Flexibility, an organizational capability that can quickly respond to changes in external conditions, was found to moderate the causal relationship between technological innovation capabilities and export performance in a positive direction. On the other hand, there was no moderating effect of flexibility in the relationship between marketing innovation capability and export performance. These results are due to conceptual attributes in which flexibility can be more friendly in the area of technological innovation than that of marketing, and the organizational characteristics of technological innovation-type SMEs. In other words, the interaction between flexibility and technological innovation capabilities appears relatively larger when the companies pursue a competitive advantage in the global market through a differentiation strategy. The significance and implications of this study are as follows. In the theoretical realm, the moderating effect of flexibility was found to be a factor that affects the export performance of innovative SMEs. In the field of practice, when companies use flexibility as a priority means to achieve a competitive advantage in the global market, managers are requested to manage operations management and marketing activities consistently according to the business strategies designed by this priority. 본 연구는 기술혁신형 중소기업의 혁신역량과 수출성과 간의 인과관계에 영향을 미치는 새로운 요인을 탐색한다. 글로벌 시장의 급변하는 환경에서는 혁신역량을 갖춘 중소기업이라 하더라도 외부조건의 변화에 실제로 어떻게 반응하느냐는 기업마다 차이가 있을 수 있다. 따라서 본 연구의 목적은 혁신역량과 수출성과 간의 단선적인 인과관계만으로는 설명되지 않는 갭을 규명하는 것이다. 즉 글로벌 시장에서 고객이나 경쟁자와 같은 시장조건의 변화에 신속하게 대응할 수 있는 조직의 유연성이 양자 간의 관계를 어떻게 조절하는지를 분석한다. 이를 위해 수출성과를 종속변수로, 대표적 혁신유형인 기술혁신역량과 마케팅혁신역량을 독립변수로, 그리고 조직의 유연성을 조절변수로 설정한 연구모델을 설계하였다. 이 모델을 추정하기 위해 이노비즈 기업을 대상으로 데이터를 수집하여 다중회귀분석과 조절회귀분석을 실시하였다. 분석 결과, 기술혁신형 중소기업의 맥락에서도 기술혁신역량과 마케팅혁신역량은 모두 수출성과에 긍정적인 영향을 미치는 것으로 나타났다. 조절변수인 유연성은 기술혁신역량과 수출성과 간의 인과관계를 정(+)의 방향으로 조절하는 것으로 나타났다. 반면에 마케팅혁신역량과 수출성과 간의 관계에서는 유연성의 조절효과가 나타나지 않았다. 이 같은 결과는 유연성이 마케팅혁신 영역보다는 기술혁신 영역에 더 친화적일 수 있는 개념적 속성과 기술혁신형 중소기업의 조직 특성에 기인한다. 즉 유연성과 기술혁신역량 간의 상호작용은 기술혁신형 기업이 차별화전략을 통해 글로벌 시장에서 경쟁우위를 추구할 경우에 상대적으로 더 크게 나타날 수 있다. 본 연구의 의의와 시사점은 다음과 같다. 이론적으로 혁신형 중소기업의 수출성과 요인으로서 유연성의 조절효과를 발견한 것이다. 실무적으로는 혁신형 중소기업이 경쟁우위를 달성하는데 유연성을 우선적인 수단으로 사용할 경우 경영자는 이 우선순위에 따라 생산관리와 마케팅할동이 일관성 있게 계획되고 실행되도록 관리해야 된다.

X-ray irradiation as a quarantine treatment for the control of six insect pests in cut flower boxes

윤승환,구현나,김현경,양정오,김길하 한국응용곤충학회 2016 Journal of Asia-Pacific Entomology Vol.19 No.1

Roses and chrysanthemums are the most exported cut flowers in Korea.We investigated the effects of X-ray irradiation on the disinfestation of six floriculture insect pests (Tetranychus urticae, Myzus persicae, Bemisia tabaci, Liriomyza trifolii, Spodoptera litura, andFrankliniella intonsa) placed in the top, middle, and bottomsections of rose and chrysanthemum boxes. After irradiation with an X-ray dose of 150 Gy, the development of nymphs and adults of M. persicae and eggs, nymphs, and adults of B. tabaci was prevented at every position in the boxes. When T. urticae nymphs were irradiated at 200 Gy, newly emerged adults laid eggs in the bottom section of rose boxes only. However, hatching was completely inhibited. When L. trifolii adults were irradiated at 200 Gy, hatching of the F1 generation was completely inhibited in every section of both the rose and chrysanthemum boxes. The hatchability of S. litura was not completely inhibited in the bottom sections, even at 200 Gy. In F. intonsa, the hatchability of eggs and emergence of nymphs were prevented at 150 Gy. However, at 200 Gy, the hatching of the F1 generation was completely inhibited only in the chrysanthemumboxes. These results suggest that the required dose of X-ray irradiation may depend on the type of flower, the species of insect pest, and the insect location within the box.

임시 수복물 중합시 시간과 중합온도가 변연 적합도에 미치는 효과

윤승환,오남식,김일규,오성섭,최진호,김왕식,임영일,Youn Seung-Hwan,Oh Nam-Sik,Kim Il-Kyu,Oh Sung-Seop,Choi Jin-Ho,Kim Wang-Sik,Rim Young-Il 대한치과보철학회 2001 대한치과보철학회지 Vol.39 No.5

The purpose of this study was to compare the marginal fit of provisional restorations by differentiating the removal time and setting temperature during resin polymerization. After mixing autopolymerizing methyl methacrylate resin, the material was placed in a preformed resin shell crown. The crown was seated on a die with 1mm shoulder margin. Crowns were removed after 3, 4, 5, 6 minutes and polymerization was continued under the following conditions : $25^{\circ}C$ air, $30^{\circ}C,\;40^{\circ}C,\;50^{\circ}C,\;60^{\circ}C,\;70^{\circ}C$ water. After polymerization. the crown was sectioned. The marginal & occlusal discrepancies were measured. The mean marginal discrelpancies at 3 minutes, 4 minutes, 5 minutes and 6 minutes of removing time were $96.6{\mu}m.\;84.6{\mu}m,\;86.7{\mu}m$ and $105.6{\mu}m$. The mean occlusal discrepancies at 3 minutes, 4 minutes, 5 minutes and 6 minutes of removing time were $106.7{\mu}m,\;89.3{\mu}m,\;98.6{\mu}m$ and $127.7{\mu}m$. There was significant difference between 4 minutes group and 6 minutes group in occlusal discrepancies. The mean marginal & occlusal discrepancies for crowns polymerized in $25^{\circ}C$ air were $98.2{\mu}m$ and $124.1{\mu}m$. The crowns polymerized in $50^{\circ}C$ water demonstrated the smallest marginal & occlusal. discrepancies. The mean value of marginal & occlusal discrepancies in $50^{\circ}C$ water were $73.1{\mu}m$ and $77.5{\mu}m$. These values were smaller than that of $25^{\circ}C$ air. There were significant differences in the occlusal discrepancies between $25^{\circ}C$ air and water conditions of $50^{\circ}C$ water (${\alpha}=0.05$) but. no significant difference in marginal discrepancies. There was no significant difference in the interaction between time and temperature. 4 minutes waiting time & $50^{\circ}C$ water polymerizing condition produces the best fit at the margin of the provisional crown.

본태성 수장부 다한증 환자에서 선택적인 T3 교감신경 차단술

윤승환,조준,문창택,장상근,배기만,Youn, Seung-Hwan,Cho, Joon,Moon, Chang-Taek,Chang, Sang-Keun,Bae, Ki-Man 대한신경외과학회 2000 Journal of Korean neurosurgical society Vol.29 No.11

Objectives : In general, conventional T2, T3 thoracoscopic sympathicotomy must be one of the most effective treatments for the essential palmar hyperhidrosis. However, this is offset by the occurrence of a high rate of side effects, such as embarrassing compensatory sweating and Hornor's syndrome. The authors have performed a selective T3 thoracoscopic sympathicotomy to our patients to see whether it provides successful results with less side effects. Its preliminary results were compared with those of conventional T2, T3 thoracoscopic sympathicotomy. Methods : The thoracoscopic sympathicotomy was performed in 54 patients suffering from essential palmar hyperhidrosis. Twenty-four patients underwent a conventional sympathicotmy(group A) from Jan 1997 to Dec 1997 and 30 patients a selective T3 sympathicotmy(group B) from Jan 1998 to Dec 1999. For assessment of postoperative success and of complications all patients charts were reviewed. Patients further received a postal questionnaire regarding long-term effect, satisfaction, and side-effects. Results : No recurrence was observed in both groups. The global rate of compensatory sweating was significantly(p =0.020) different in both groups : 11 patients(45.8%) in group A and 5 patients(16.73%) in group B. The Hornor's syndrome was observed only in 4 patients in group A. The preliminary results of the procedure in group A were considered fully-satisfying by 16 patients(66.6%), 6 patients(25%) were satisfied partially, and only 2 patients(8.3%) were dissatisfied, and those of the procedure in group B satisfying by 26 patients(86.6%), 4 patients(13.3.% ) were satisfied partially, and none dissatisfied. Conclusion : The selective T3 sympathicotomy results in a significant decrease in the rate of disturbing side effects comparing to conventional T2, T3 sympathicotomy and it dose not lead to recurrence. Our results contribute to recommendations of a selective T3 thoracoscopic sympathicotomy as treatment of choice in essential palmar hyperhidrosis.

척추 압박골절의 체위를 이용한 정복술

윤승환,김근수,장호열,김영수 대한신경외과학회 1996 Journal of Korean neurosurgical society Vol.25 No.7

12l patients with cervical(45 patients). thoracolumbar(76 patients) compression or mild burst fractures from January 1984 to December 1994 were studied : 98 patients were treated postural reduction with hyperextension posture and 23 patients were with postural reduction and surgical methods We compared the initial and post-reduction compression height ratio. wedge angls and kyphosis angle of compression fractures The results were not only expansion of a compressed vertebral body but also successful fusion. The neurological recovery status according to Frankei classification was also improved after postural reduction. Most of the compression fractures or stable burst fractures of the cervical. thoracolumbar spines can be restored by the postural reduction