• 제목/요약/키워드: Magnetic attachment

검색결과 77건 처리시간 0.022초

Mobility of Intradural Extramedullary Schwannoma at Spine : Report of Three Cases with Literature Review

  • Kim, Soo-Beom;Kim, Hyung-Seok;Jang, Jee-Soo;Lee, Sang-Ho
    • Journal of Korean Neurosurgical Society
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    • 제47권1호
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    • pp.64-67
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    • 2010
  • Although very rare, a few cases of intradural extramedullary (IDEM) spinal tumor migration have been reported since Tomimatsu first reported a mobile schwannoma of the cervical cord in 1974. Schwan noma is a neurogenic tumor which originates from nerve sheath that it is relatively well-marginated tumor with little attachment or adhesion to surrounding tissue. Mobility of tumor in spinal canal sometimes can result in negative exploration at the expected area. We found three interesting cases in which different tumor locations observed in repeated magnetic resonance image (MRI) findings. All tumors were intradural and extramedullary schwannoma. We reviewed the literature about moving tumor in the spine through PUBMED search.

SNARE Assembly and Membrane Fusion: A Paramagnetic Electron Magnetic Resonance Study

  • Kweon, Dae-Hyuk
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 2003년도 정기총회 및 학술발표회
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    • pp.32-32
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    • 2003
  • In the neuron, SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptors) assembly plays a central role in driving membrane fusion, a required process for neurotransmitter release. In the cytoplasm, vesicular SNARE VAMP2 (vesicle-associated membrane protein 2) engages with two plasma membrane SNAREs syntaxin 1A and SNAP-25 (synaptosome-associated protein of 25 kDa) to form the core complex that bridges two membranes. While various factors regulate SNARE assembly, the membrane also plays the regulatory role by trapping VAMP2 in the membrane. The fluorescence and EPR analyses revealed that the insertion of seven C-terminal core-forming residues into the membrane controls complex formation of the entire core region, even though preceding 54 core-forming residues are fully exposed and freely moving. When two interfacial Trp residues in this region were replaced with hydrophilic serine residues, the mutation supported rapid complex formation.

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자력에 의한 산성 광산 배수의 처리 - 철(Fe) 성분의 제거- (The Treatment of Acid Mine Drainage - The removal of Iron(Fe) component-)

  • 송근호;이광래
    • 산업기술연구
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    • 제32권A호
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    • pp.21-27
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    • 2012
  • The characteristics of floc formation of the iron(Fe) ions contained in the acid mine drainage was studied for developing the process treating the acid mine drainage. The iron(Fe) ions were formed into flocs by the acid-base reaction with the added $Ca(OH)_2$. The molal ratio of iron(Fe) vs $Ca(OH)_2$ was one of major control variables in treatment; pH change, iron(Fe) ions concentration in treated drainage, DO (dissolved oxygen content). In addition, the air gave much effect on the color of the $iron(Fe)-Ca(OH)_2$ flocs and the attachment to magnet. The attaching to the magnet of the flocs formed in the air was much less than the case without air.

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Influence of marginal bone resorption on two mini implant-retained mandibular overdenture: An in vitro study

  • Guo, Ying;Kono, Kentaro;Suzuki, Yasunori;Ohkubo, Chikahiro;Zeng, Jian-Yu;Zhang, Jing
    • The Journal of Advanced Prosthodontics
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    • 제13권1호
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    • pp.55-64
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    • 2021
  • PURPOSE. To investigate the biomechanical effect of marginal bone resorption (MBR) on the mandibular mini implant (MI)-retained overdenture (MI-OD) on the edentulous model. MATERIALS AND METHODS. The experimental mandibular edentulous model was modified from a commercial model with 2 mm thick artificial soft tissue under denture base. Two MIs (Φ2.6 mm × 10 mm) were bilaterally placed between the lateral incisor and the canine area and attached with magnetic attachments. Three groups were set up as follows: 1) alveolar bone around the MI without MBR (normal group), 2) with MBR to 1/2 the length of the implant (resorption group), and 3) complete denture (CD) without MI (CD group). Strain around the MI, pressure near the first molar area, and displacement of denture were simultaneously measured, loading up to 50 N under bilateral/unilateral loading. Statistical analysis was performed using independent-samples t test and one-way ANOVA (α=.05). RESULTS. The strain around the MI with MBR was approximately 1.5 times higher than that without MBR. The pressure in CD was higher than in MI-ODs (P<.05), while there was no statistical difference between the normal and resorption group (P>.05). Similarly, the CD demonstrated a greater displacement of the denture base than did the MI-ODs during bilateral and unilateral loadings (P<.05). CONCLUSION. The strain around the MI with MBR was approximately 1.5 times higher than that without MBR. The pressure on posterior alveolar ridge and denture displacement of MI-ODs significantly decreased compared to CDs, even when MBR occurs. Bilateral balanced occlusion was recommended for MI-ODs, especially when MBR occurred.

Intraparenchymal Atypical Meningioma in Basal Ganglia Region in a Child : Case Report and Literature Review

  • Liu, Xiaowei;Zhang, Yuekang;Zhang, Si;Tao, Chuanyuan;Ju, Yan
    • Journal of Korean Neurosurgical Society
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    • 제61권1호
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    • pp.120-126
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    • 2018
  • Intraparenchymal meningiomas without dural attachment are extremely rare, especially when they occur in basal ganglia region in child. An 8-year-old boy was admitted at our hospital, complaining of recurrent headache and vomiting for 3 months. Neurological examination showed impaired vision and mild paresis of the left extremities. Magnetic resonance imaging demonstrated a lesion located in the right basal ganglia region extending to superasellar cistern with solid, multiple cystic and necrotic components. Computed tomography revealed calcification within the mass. Due to the anterior cerebral artery involvement, a subtotal resection was achieved and postoperative radiotherapy was recommended. Histopathological examination indicated that the lesion was an atypical meningioma. The postoperative rehabilitation was uneventful. Mildly impaired vision and motor weakness of left extremities improved significantly and the patient returned to normal life after surgery. To our knowledge, intraparenchymal atypical meningioma in basal ganglia extending to superasellar cistern was never reported. The significance in differential diagnosis of lesions in basal ganglia should be emphasized.

Destructive Radiologic Development of Intravascular Papillary Endothelial Hyperplasia on Skull Bone

  • Lee, Seul-Kee;Jung, Tae-Young;Baek, Hee-Jo;Kim, Seul-Kee
    • Journal of Korean Neurosurgical Society
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    • 제52권1호
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    • pp.48-51
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    • 2012
  • Intravascular papillary endothelial hyperplasia (IPEH) is a rare vascular benign lesion that rarely involves the central nervous system with or without skull invasion. We report a rare case of IPEH on the skull bone, which displayed destructive radiologic development associated with hemorrhage. A 14-year-old male presented with an incidentally detected a small enhancing, left frontal osteolytic lesion. Previously, he underwent operation and received adjuvant chemoradiation therapy for cerebellar medulloblastoma. Follow-up magnetic resonance imaging revealed a left frontal bone lesion, which expanded to an approximately 2 cm-sized well-circumscribed osteolytic lesion associated with hemorrhage for 20 months. Frontal craniectomy and cranioplasty were performed. Destructive change was detected on the inner table and diploic space of the skull. The mass had a cystic feature with hemorrhagic content without dural attachment. Pathologic examination showed the capsule consisted of parallel collagen lamellae representing a vascular wall, vascular lumen, which was pathognomonic for IPEH. Immunohistochemical staining revealed that the capsule was positive for CD34 and factor VIII, which favor the final diagnosis of IPEH. This was the first case of intracalvarial IPEH.

Non-Dural-Based Spinal Meningioma : The First Case Report of a Fibrous Subtype and a Review of the Literature

  • Lee, Ji Hye;Moon, Hong Joo;Kim, Joo Han;Park, Youn-Kwan
    • Journal of Korean Neurosurgical Society
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    • 제56권1호
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    • pp.58-60
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    • 2014
  • Spinal meningiomas typically adhere to the dura matter. Non-dural based spinal meningiomas are rare and most are clear cell meningiomas. We report here the first case of a fibrous meningioma with non-dural attachment. The patient was a 49-year-old female, who complained of numbness in the legs and a gait disturbance. Magnetic resonance imaging revealed a $1.7{\times}1.4-cm$ mass in the C7-T1 intra-dural extramedullary space, showing peripheral gadolinium enhancement without a "dural tail sign". A complete microsurgical resection was performed. The mass was covered with a white membrane but was not adhered to the dura, and its appearance was consistent with a neurilemmoma. The histopathological diagnosis was fibrous-type meningioma. The recovery of the patient was uneventful. No surgical complications and no recurrence of the tumor had occurred at the 6-month follow-up.

파킨슨병 환자의 자성 피개의치 수복 증례 (Overdenture with magnetic attachments for a patient with Parkinson's disease: a case report)

  • 마보영;민병귀;양홍서;박상원;임현필;윤귀덕;박찬;신진호
    • 구강회복응용과학지
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    • 제32권4호
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    • pp.301-306
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    • 2016
  • 총의치 환자에 있어 환자가 만족할 만한 의치의 유지와 안정을 얻는 것은 어려운 일이다. 특히 파킨슨병 등의 전신질환으로 하악에서 불수의적 운동이나 운동제한이 나타나는 환자에 있어서, 총의치의 기능적 한계는 임상가에게 더욱 더 힘든 문제이다. 이러한 어려움을 극복하기 위해 잔존치근의 보존을 통한 피개의치가 도움이 될 것이다. 본 증례는, 45세 남성환자로, 내원 당시 당뇨와 파킨슨 병의 약을 장기 복용 중이었고 우식으로 인해 대다수의 치아를 발치해야 했다. 상악은 총의치, 하악은 2개의 잔존 치근을 이용한 자성 어태치먼트로 유지와 안정을 증진시킨 피개의치 증례로서, 기능적으로 개선된 보철물을 제작했기에 보고하는 바이다.

Effect of negative oxygen ion bombardment on the gate bias stability of InGaZnO

  • 이동혁;김경덕;홍문표
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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    • pp.160-160
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    • 2015
  • InGaZnO (IGZO) thin-film transistors (TFTs) are very promising due to their potential use in high performance display backplane [1]. However, the stability of IGZO TFTs under the various stresses has been issued for the practical IGZO applications [2]. Up to now, many researchers have studied to understand the sub-gap density of states (DOS) as the root cause of instability [3]. Nomura et al. reported that these deep defects are located in the surface layer of the IGZO channel [4]. Also, Kim et al. reported that the interfacial traps can be affected by different RF-power during RF magnetron sputtering process [5]. It is well known that these trap states can influence on the performances and stabilities of IGZO TFTs. Nevertheless, it has not been reported how these defect states are created during conventional RF magnetron sputtering. In general, during conventional RF magnetron sputtering process, negative oxygen ions (NOI) can be generated by electron attachment in oxygen atom near target surface and accelerated up to few hundreds eV by self-bias of RF magnetron sputter; the high energy bombardment of NOIs generates bulk defects in oxide thin films [6-10] and can change the defect states of IGZO thin film. In this study, we have confirmed that the NOIs accelerated by the self-bias were one of the dominant causes of instability in IGZO TFTs when the channel layer was deposited by conventional RF magnetron sputtering system. Finally, we will introduce our novel technology named as Magnetic Field Shielded Sputtering (MFSS) process [9-10] to eliminate the NOI bombardment effects and present how much to be improved the instability of IGZO TFTs by this new deposition method.

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Effect of Negative Oxygen Ions Accelerated by Self-bias on Amorphous InGaZnO Thin Film Transistors

  • 김두현;윤수복;홍문표
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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    • pp.466-468
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    • 2012
  • Amorphous InGaZnO (${\alpha}$-IGZO) thin-film transistors (TFTs) are are very promising due to their potential use in thin film electronics and display drivers [1]. However, the stability of AOS-TFTs under the various stresses has been issued for the practical AOSs applications [2]. Up to now, many researchers have studied to understand the sub-gap density of states (DOS) as the root cause of instability [3]. Nomura et al. reported that these deep defects are located in the surface layer of the ${\alpha}$-IGZO channel [4]. Also, Kim et al. reported that the interfacial traps can be affected by different RF-power during RF magnetron sputtering process [5]. It is well known that these trap states can influence on the performances and stabilities of ${\alpha}$-IGZO TFTs. Nevertheless, it has not been reported how these defect states are created during conventional RF magnetron sputtering. In general, during conventional RF magnetron sputtering process, negative oxygen ions (NOI) can be generated by electron attachment in oxygen atom near target surface and accelerated up to few hundreds eV by self-bias of RF magnetron sputter; the high energy bombardment of NOIs generates bulk defects in oxide thin films [6-10] and can change the defect states of ${\alpha}$-IGZO thin film. In this paper, we have confirmed that the NOIs accelerated by the self-bias were one of the dominant causes of instability in ${\alpha}$-IGZO TFTs when the channel layer was deposited by conventional RF magnetron sputtering system. Finally, we will introduce our novel technology named as Magnetic Field Shielded Sputtering (MFSS) process [9-10] to eliminate the NOI bombardment effects and present how much to be improved the instability of ${\alpha}$-IGZO TFTs by this new deposition method.

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