• 제목/요약/키워드: secondary fluid

검색결과 449건 처리시간 0.027초

Risk Factors Associated with Subdural Hygroma after Decompressive Craniectomy in Patients with Traumatic Brain Injury : A Comparative Study

  • Jeon, Sei-Woong;Choi, Jong-Hun;Jang, Tae-Won;Moon, Seung-Myung;Hwang, Hyung-Sik;Jeong, Je-Hoon
    • Journal of Korean Neurosurgical Society
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    • 제49권6호
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    • pp.355-358
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    • 2011
  • Objective : Subdural hygroma (SDG) is a complication occurring after head trauma that may occur secondary to decompressive craniectomy (DC). However, the mechanism underlying SDG formation is not fully understood. Also, the relationship between the operative technique of DC or the decompressive effect and the occurrence and pathophysiology of SDG has not been clarified. Purpose of this study was to investigate the risk factors of SDG after DC in our series. Methods : From January 2004 to December 2008, DC was performed in 85 patients who suffered from traumatic brain injury. We retrospectively reviewed the clinical and radiological features. For comparative analysis, we divided the patients into 2 groups : one group with SDG after craniectomy (19 patients; 28.4% of the total sample), the other group without SDG (48 patients; 71.6%). The risk factors for developing SDG were then analyzed. Results : The mean Glasgow Outcome Scale (GOS) scores at discharge of the groups with and without SDG were 2.8 and 3.1, respectively (p<0.0001). Analysis of radiological factors showed that a midline shift in excess of 5 mm on CT scans was present in 19 patients (100%) in the group with SDG and in 32 patients (66.7%) in the group without SDG (p<0.05). An accompanying subarachnoid hemorrhage (SAH) was seen in 17 patients (89.5%) in the group with SDG and in 29 patients (60.4%) in the group without SDG (p<0.05). Delayed hydrocephalus accompanied these findings in 10 patients (52.6%) in the group with SDG, versus 5 patients (10.4%) in the group without SDG (p<0.05). On CT, compression of basal cisterns was observed in 14 members (73.7%) in the group with SDG and in 18 members of the group without SDG (37.5%) (p<0.007). Furthermore, tearing of the arachnoid membrane, as observed on CT, was more common in all patients in the group with SDG (100%) than in the group without SDG (31 patients; 64.6%) (p<0.05). Conclusion : GOS showed statistically significant difference in the clinical risk factors for SDG between the group with SDG and the group without SDG. Analysis of radiological factors indicated that a midline shifting exceeding 5 mm, SAH, delayed hydrocephalus, compression of basal cisterns, and tearing of the arachnoid membrane were significantly more common in patients with SDG.

급확대관내에서 류유선회유동의 열전달에 관한 연구 (An Experimental Study of the Turbulent Swirling Flow and Heat Transfer Downstream of an Abrupt Expansion in a Circulat Pipe with Uniform Heat Flux)

  • 권기린;허종철
    • 한국해양공학회지
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    • 제10권3호
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    • pp.138-152
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    • 1996
  • Many studies of heat transfer on the swirling flow or unswirled flow in a abrupt pipe expansion are widely carried out. The mechanism is not fully found evidently due to the instabilities of flow in a sudden change of the shape and appearance of turbulent shear layers in a recirculation region and secondary vortex near the corner. The purpose of this study is to obtain data through an experimental study of the swirling flow and heat transfer downstream of an abrupt expansion in a circular pipe with uniform heat flux. Experiments were carried out for the turbulent flow nd heat transfer downstream of an abrupt circular pipe expansion. The uniform heat flux condition was imposed to the downstream of the abrupt expansion by using an electrically heated pipe. Experimental data are presented for local heat transfer rates and local axial velocities in the tube downstream of an abrupt 3:1 & 2:1 expansion. Air was used as the working fluid in the upstream tube, the Reynolds number was varied from 60, 00 to 120, 000 and the swirl number range (based on the swirl chamber geometry, i.e. L/d ratio) in which the experiments were conducted were L/d=0, 8 and 16. Axial velocity increased rapidly at r/R=0.35 in the abrupt concentric expansion turbulent flow through the test tube in unswirled flow. It showed that with increasing axial distance the highest axial velocities move toward the tube wall in the case of the swirling flow abrupt expansion. A uniform wall heat flux boundary condition was employed, which resulted in wall-to-bulk temperatures ranging from 24.deg. C to 71.deg. C. In swirling flow, the wall temperature showed a greater increase at L/d=16 than any other L/d. The bulk temperature showed a minimum value at the pipe inlet, it also exhibited a linear increase with axial distance along the pipe. As swirl intensity increased, the location of peak Nu numbers was observed to shift from 4 to 1 step heights downstream of the expansion. This upstream movement of the maximum Nusselt number was accompanied by an increase in its magnitude from 2.2 to 8.8 times larger than fully developed tube flow values.

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A Clinical Analysis of Secondary Surgery in Trigeminal Neuralgia Patients Who Failed Prior Treatment

  • Kang, Il Ho;Park, Bong Jin;Park, Chang Kyu;Malla, Hridayesh Pratap.;Lee, Sung Ho;Rhee, Bong Arm
    • Journal of Korean Neurosurgical Society
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    • 제59권6호
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    • pp.637-642
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    • 2016
  • Objective : Although many treatment modalities have been introduced for trigeminal neuralgia (TN), the long-term clinical results remain unsatisfactory. It has been particularly challenging to determine an appropriate treatment strategy for patients who have responded poorly to initial therapies. We analyzed the surgical outcomes in TN patients who failed prior treatments. Methods : We performed a retrospective analysis of 37 patients with recurrent or persistent TN symptoms who underwent surgery at our hospital between January 2010 and December 2014. Patients with follow-up data of at least one year were included. The prior treatment modalities of the 37 patients included microvascular decompression (MVD), gamma knife radiosurgery (GKRS), and percutaneous procedures such as radiofrequency rhizotomy (RFR), balloon compression, and glycerol rhizotomy (GR). The mean follow-up period was 69.9 months (range : 16-173). The mean interval between the prior treatment and second surgery was 26 months (range : 7-123). We evaluated the surgical outcomes using the Barrow Neurological Institute (BNI) pain intensity scale. Results : Among the 37 recurrent or persistent TN patients, 22 underwent MVD with partial sensory rhizotomy (PSR), 8 received MVD alone, and 7 had PSR alone. Monitoring of the surgical treatment outcomes via the BNI pain intensity scale revealed 8 (21.6%) patients with a score of I, 13 (35.1%) scoring II, 13 (35.1%) scoring III, and 3 (8.2%) scoring IV at the end of the follow-up period. Overall, 91.8% of patients had good surgical outcomes. With regard to postoperative complications, 1 patient had transient cerebrospinal fluid rhinorrhea (2.7%), another had a subdural hematoma (2.7%), and facial sensory changes were noted in 8 (21.1%) patients after surgery. Conclusion : Surgical interventions, such as MVD and PSR, are safe and very effective treatment modalities in TN patients who failed initial or prior treatments. We presume that the combination of MVD with PSR enabled us to obtain good short- and long-term surgical outcomes. Therefore, aggressive surgical treatment should be considered in patients with recurrent TN despite failure of various treatment modalities.

2006-2010년 단일기관 소아에서의 엔테로바이러스 감염 역학 및 임상 양상에 관한 연구 (Epidemiology and Clinical Characteristics of Enterovirus Infections in Children: A Single Center Analysis from 2006 to 2010)

  • 박인수;이해성;최수한;김혜진;황서연;천두성;장진근
    • Pediatric Infection and Vaccine
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    • 제20권2호
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    • pp.81-88
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    • 2013
  • 목 적 : 본 연구는 최근 5년간 엔테로바이러스의 분자유전학적 역학 및 임상 양상을 조사하고자 하였다. 방 법 : 2006년부터 2010년까지 한전병원에서 엔테로바이러스 감염이 의심되는 소아 환자의 검체를 질병관리본부로 의뢰하였고, 감염이 확진된 환자를 후향적으로 분석하였다. 결 과 : 277명 환자에서 386개의 검체가 분석되었고 그 중 적어도 한 개 이상의 검체에서 양성을 소견을 보인 환자는 총 98명(35.4%) 이었다. 98명의 환자로부터 100개의 엔테로바이러스가 확인되었고, echovirus 30형 28건(28%), enterovirus 71형 12건(12%), echovirus 25형 10건(10%), echovirus 9형 9건(9%), coxsackievirus A6형 8건(8%) 순이었다. 연도별 분포는 2006년과 2008년에 각각 echovirus 25형 및 echovirus 30형에 의한 무균성 뇌수막염이 각각 61.5% 및 69.2%로 대부분을 차지하였다. Enterovirus 71형에 의한 합병증을 동반한 환자는 없었다. 결 론 : 단일기관에서 최근 5년간 분리된 엔테로바이러스 감염 양상을 확인하였고 우리나라 소아에서의 최근 역학을 파악하는 데 도움이 될 것으로 사료된다.

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기상 조건과 매립 조건이 비산 먼지 발생에 미치는 영향 (Effects of Meteorological and Reclaiming Conditions on the Reduction of Suspended Particles)

  • 최재원;이영수;김재진
    • 한국환경과학회지
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    • 제19권11호
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    • pp.1423-1436
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    • 2010
  • The effects of meteorological and reclaiming conditions on the reduction of suspended particles are investigated using a computational fluid dynamics (CFD) model with the k-$\varepsilon$ turbulence closure scheme based on the renormalization group (RNG) theory. Twelve numerical experiments with different meteorological and reclaiming conditions are performed. For identifying the meteorological characteristics of the target area and providing the inflow conditions of the CFD model, the observed data from the automatic weather station (AWS) near the target area is analyzed. Complicated flow patterns such as flow distortion, horse-shoe vortex, recirculation zone, and channeling flow appeared due to the topography and buildings in the domain. Specially, the flow characteristics around the reclamation area are affected by the reclaiming height, reclaiming size and windbreak height. Reclaiming height affected the wind speed above the reclaiming area. Windbreak induces more complicated flow patterns around the reclaiming area as well as within the reclaiming area. In front of the windbreak, flow is distorted as it impinges on the windbreak. As a result, upward flow is generated there. Behind the windbreak, a secondary circulation, so called, a recirculation zone is generated and flow is reattached at the end of the recirculation zone (reattachment point). At the lower part of the recirculation zone, there is a reverse flow toward the windbreak. Flow passing to the reattachment point starts to be recovered. Total amounts of suspended particles are calculated using the frictional and threshold frictional velocities, erosion potential function, and the number of surface disturbance. In the case of a 10 m-reclaiming and northerly wind, the amount of suspended particles is largest. In the presence of 5 m windbreak, the friction velocity above the reclaiming area is largely reduced. As a result, the total amount of the suspended particles largely decreases, compared to the case with the same reclaiming and meteorological conditions except for the windbreak The calculated suspended particle amounts are used as the emission rate of the dispersion model simulations and the dispersion characteristics of the suspended particles are analyzed.

악성 종양 표지자가 상승된 만성 흉수를 동반한 종격동 기형종 1예 (A Case of Mediastinal Teratoma Associated with Elevated Tumor Marker in Chronic Empyema)

  • 엄수정;양두경;이수걸;손춘희;노미숙;김기남;이기남;최필조;방정희
    • Tuberculosis and Respiratory Diseases
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    • 제66권2호
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    • pp.127-131
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    • 2009
  • 기형종은 주로 전 종격동에서 발생하는 양성 종양으로 대부분 무증상이며 검사에서 우연히 발견된다. 드물게 기형종이 파열하여 여러 합병증을 일으키는 것으로 알려져 있으며 합병증은 급성 증상을 동반한다. 저자들은 급성 증상없이 만성적인 경과를 보인 기형종 파열 1예를 경험 하였다. 환자는 왼쪽 폐에 다량의 흉수가 있었는데 배액관 삽입으로 증상이 호전되었으며 지속적으로 흉수의 carcinoembryonic antigen (CEA) 및 carbohydrate antigen 19-9 (CA19-9)이 증가되어서 악성 흉수를 동반하는 종양과 구별이 어려웠다. 본 증례는 이차 감염에 의한 농흉을 치료하기 위해 흉강경으로 확인하기 전까지는 확진이 어려웠고, 매우 높은 흉수 내 악성 종양 표지자 수치를 보인 증례가 국내에는 보고되지 않았으므로 유사 증례의 문헌 고찰과 함께 보고한다.

CFD를 이용한 유리온실 내부 환경 예측 모델 개발 및 검증 (Development and Validation of Inner Environment Prediction Model for Glass Greenhouse using CFD)

  • 정인선;이충건;조라훈;박선용;김민준;김석준;김대현
    • 생물환경조절학회지
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    • 제29권3호
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    • pp.285-292
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    • 2020
  • 본 연구에서는 CFD 시뮬레이션 기법을 이용하여 유리온실의 내부 환경 변화를 예측하는 모델을 개발하였으며, 실험을 통해 확보한 데이터를 이용하여 이를 검증하였다. 주·야간 실험 데이터를 경계조건으로 하는 Case 1, 2, 3의 시뮬레이션 예측값은 실험값 대비 평균 2.62℃ 높게 나타났으며, 최대편차와 균일도는 각각 평균 1.12℃, 2.92%p 높게 나타났다. Case 1에서 Case 3으로 외기온도가 변화함에 따라 조성되는 온실 내부 온도는 평균 0.84℃의 차이를 보였으며, R2는 0.9628로 실험값과 시뮬레이션 예측값 간 유사한 경향을 보임을 확인하였다. 시뮬레이션 예측 결과 해석대상 온실 내 불균일한 온도분포를 확인하였다. 해석대상 온실의 효율적인 열에너지 관리를 위해 온실 내 방열관과 FCU의 위치 변경, 온실 구조 변경 등이 필요하다고 판단되었다. 추후 현장에서의 적용을 위해 정밀한 분석이 필요하며 이를 위해 온실 내부 작물 및 구조물 미고려, 온실을 완전 밀폐로 가정하는 등 모델 정립을 위한 조건들에 의한 열전달 현상을 고려한 모델의 개선이 필요하다고 판단된다.

초임계이산화탄소 하에서 QCM을 이8한 I-TEDA의 제거특성 측정 (Measurement of I-TEDA Removal Rate Using QCM in Supercritical Carbon Dioxide)

  • 유재룡;고문성;성진현;이정근;박광헌
    • 청정기술
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    • 제14권2호
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    • pp.110-116
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    • 2008
  • 원자력산업이 발생하는 방사성폐기물은 고체, 액체 그리고 기체상으로 구분된다. 특히 기체상 방사성폐기물인 방사성 메틸요오드는 활성탄을 이용하여 흡착된다. 이때 활성탄에는 방사성 메틸요오드를 보다 효율적으로 포집하기 위해 5 wt%의 트리에틸렌다이아민 (Trietylenediamine; 1,4-diazania-bicycle[2.2.2]octane, TEDA)이 첨착되어 있다. 일반적으로 대기중에서 TEDA와 메틸요오드($CH_3I$)는 I-TEDA(TEDA와 메틸요오드 결합물)를 형성하게 된다. 방사성 요오드를 포집한 방사성 폐 활성탄을 재사용하기 위해서는, 이러한 형태의 I-TEDA를 제거해야 하는데, 현재는 아세토나이트릴을 이용한 습식재활용법이 개발되었다. 그러나 이러한 습식재활용법은 다량의 2차폐기물을 발생하는 문제점이 있기 때문에, 본 연구에서는 I-TEDA를 제거하기 위한 방법으로 초임계이산화탄소를 기본용매로써 사용하였으며, 수정미량저울(Quartz Crystal Microbalance, QCM)을 이용하여 I-TEDA의 제거율을 측정하였다. 실험결과 I-TEDA를 제거하기 위해 추출을 위한 첨가용액으로 메탄올이 가장 적합하였고, 최적화된 온도, 압력 및 추출용매의 유량조건을 찾아내었다. 이러한 결과를 바탕으로 하여 방사성 폐활성탄으로부터 I-TEDA를 제거할 수 있는 가능성에 대한 검토를 하였다.

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성장에 따른 외모 걱정의 추이: 한국 청소년의 사례를 중심으로 (Trajectories of Appearance Concerns of South Korean Adolescents)

  • 윤영민;정성호
    • Journal of health informatics and statistics
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    • 제43권4호
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    • pp.245-254
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    • 2018
  • 목적: 이 논문은 한국 청소년들의 외모 걱정이 언제 어떻게 형성되고 변화하는지를 추적하여 그것의 심각성 정도를 밝히고자 하였다. 방법: 한국청소년정책연구원이 공개한 다년간의 추적 조사 자료에 대한 이차분석이 시행되었다. 통계기법으로는 반복측정 ANOVA, 대응표본 t-검정 및 카이자승 검정이 적용되었다. 결과: 청소년들에 있어 외모에 대한 걱정은 초등학교 고학년에 시작되어 성장과 더불어 강화되다 중 2나 중 3을 지나면서 점차 약화되는 것으로 판단된다. 일부 학생들은 청소년 시기 내내 외모에 대해 걱정하는 것으로 나타났지만, 고등학교나 대학에 진학한 후에는 청소년들의 외모 걱정이 눈에 띄게 감소되었으며, 어느 시점에서 외모 걱정을 벗어난 청소년은 다시 외모 걱정에 빠질 가능성이 아주 적다는 사실도 발견되었다. 한편 외모 걱정에 성별 차이가 뚜렷이 나타났다. 평균적으로 여학생이 남학생보다 외모에 대해 더 걱정하며, 외모 걱정이 남학생보다 1-2년 정도 더 일찍 정점에 도달하였다. 결론: 청소년의 외모 걱정은 성장과 더불어 역동적으로 변화한다. 외모에 대해 심각하게 걱정하는 청소년들이 적지 않지만, 일반적으로 추정되는 것보다는 청소년들의 외모 걱정은 상당히 유동적이며 다수의 청소년들이 외모 걱정에서 자유롭다고 판단된다.

Facial Paralysis and Myositis Following the H3N2 Influenza Vaccine in a Dog

  • Ju-Hyun An;Ye-In Oh;So-Hee Kim;Su-Min Park;Jeong-Hwa Lee;Ga-Hyun Lim;Kyung-Won Seo;Hwa-Young Youn
    • 한국임상수의학회지
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    • 제40권5호
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    • pp.336-340
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    • 2023
  • A dog (2-year old, female, Shih-Tzu) presented with hyperthermia and right-sided facial paralysis characterized by the inability to close the right eye and drooling from the right side of the mouth after H3N2 influenza vaccination [A/Canine/Korea/01/07(H3N2) strain; Caniflu-Max, Bionote, Hwaseong, Gyeonggi-do, ROK]. To determine the cause of the fever and neurological symptoms, physical examination, ophthalmic examination, thoracic and abdominal radiography, abdominal ultrasonography, complete blood counts, serum chemistry values, and electrolyte levels were determined. In addition, Cerebrospinal fluid analysis, antinuclear antibody test, fever of unknown origin polymerase chain reaction (PCR) panel, tick-borne pathogen PCR panel were performed. As a result, hyperthermia, leukocytosis, and elevated C-reactive protein were confirmed. In addition, neurological examination revealed decreased right eyelid reflexes, corneal reflexes, threat response, and facial sensation, it was possible to suspect problems with the trigeminal and facial nerves of the cranial nerve. Magnetic resonance imaging revealed a lesion suggestive of myositis in the right muscular lesion at atlanto-occipital junction level on site of vaccine injection. Therefore, right-sided facial paralysis was tentatively determined to be a secondary cause of nerve damage caused by myositis. The patient was treated with immunosuppressants such as prednisolone and mycophenolate mofetil. After 3 months of immunosuppressant therapy, the patient's symptoms improved.