• 제목/요약/키워드: Neck mechanism

검색결과 132건 처리시간 0.028초

ROS Scavenger, Ebselen, Has No Preventive Effect in New Hearing Loss Model Using a Cholesterol-Chelating Agent

  • Lee, Min Young;Kabara, Lisa L.;Swiderski, Donald L.;Raphael, Yehoash;Duncan, R. Keith;Kim, Young Ho
    • 대한청각학회지
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    • 제23권2호
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    • pp.69-75
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    • 2019
  • Background and Objectives: The antioxidant ebselen will be able to limit or prevent the ototoxicity arising from 2-hydroxypropyl-β-cyclodextrin (HPβCD). Niemann-Pick Type C (NPC) disease is a disorder of lysosomal storage manifested in sphingolipidosis. Recently, it was noted that experimental use of HPβCD could partially resolve the symptoms in both animals and human patients. Despite its desirable effect, HPβCD can induce hearing loss, which is the only major side effect noted to date. Understanding of the pathophysiology of hearing impairment after administration of HPβCD and further development of preventive methods are essential to reduce the ototoxic side effect. The mechanisms of HPβCD-induced ototoxicity remain unknown, but the resulting pathology bears some resemblance to other ototoxic agents, which involves oxidative stress pathways. To indirectly determine the involvement of oxidative stress in HPβCD-induced ototoxicity, we tested the efficacy of an antioxidant reagent, ebselen, on the extent of inner ear side effects caused by HPβCD. Materials and Methods: Ebselen was applied prior to administration of HPβCD in mice. Auditory brainstem response thresholds and otopathology were assessed one week later. Bilateral effects of the drug treatments also were examined. Results: HPβCD-alone resulted in bilateral, severe, and selective loss of outer hair cells from base to apex with an abrupt transition between lesions and intact areas. Ebselen co-treatment did not ameliorate HPβCD-induced hearing loss or alter the resulting histopathology. Conclusions: The results indirectly suggest that cochlear damage by HPβCD is unrelated to reactive oxygen species formation. However, further research into the mechanism(s) of HPβCD otopathology is necessary.

Extraneural Metastasis of Glioblastoma Multiforme Presenting as an Unusual Neck Mass

  • Seo, Young-Jun;Cho, Won-Ho;Kang, Dong-Wan;Cha, Seung-Heon
    • Journal of Korean Neurosurgical Society
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    • 제51권3호
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    • pp.147-150
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    • 2012
  • Glioblastoma multiforme(GBM) is the most aggressive intracranial tumor and it commonly spreads by direct extension and infiltration into the adjacent brain tissue and along the white matter tract. The metastatic spread of GBM outside of the central nervous system (CNS) is rare. The possible mechanisms of extraneural metastasis of the GBM have been suggested. They include the lymphatic spread, the venous invasion and the direct invasion through dura and bone. We experienced a 46-year-old man who had extraneural metastasis of the G8M on his left neck. The patient was treated with surgery for 5 times, radiotherapy and chemotherapy. He had survived 6 years since first diagnosed. Although the exact mechanism of the extraneural metastasis is not well understood, this present case shows the possibility of extraneural metastasis of the G8M, especially in patients with long survival.

Multiple Cervical Spinous Process Fractures in a Novice Golf Player

  • Kim, Sei-Yoon;Chung, Sang Ki;Kim, Dong-Yun
    • Journal of Korean Neurosurgical Society
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    • 제52권6호
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    • pp.570-573
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    • 2012
  • Avulsion of spinous process, also called Clay-shoveler's fracture, is most prevalent among those engaged in hard physical labor. To the best of the author's knowledge, only one case of multiple spinous process fractures of the upper thoracic spine in a novice golfer has been reported. A 45-year-old female presented with intractable posterior neck pain. The patient experienced a sharp, sudden pain on the neck while swinging a golf club, immediately after the club head struck the ground. Dynamic cervical radiographic findings were C6 and C7 spinous process fractures. Magnetic resonance imaging revealed C6 and C7 spinous process fractures without spinal cord pathology. The patient was treated with pain medications and cervical bracing. The patient's pain gradually improved. The injury mechanism was speculated to be similar to Clay-shoveler's fracture. Lower cervical spinous process fractures can be associated with a golf swing. If the patient complains of long lasting neck pain and has a history of golf activity, further study should be conducted to rule out lower cervical spinous fracture.

SIP 프레즌스 모델 기반 센서 태그의 상태이력 추적 (Tracking and Tracing the Status Changes of Sensor Tags based on the SIP Presence Model)

  • 김동욱;홍진표
    • 한국정보과학회논문지:정보통신
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    • 제36권3호
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    • pp.231-242
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    • 2009
  • RFID객체 이력추적기술은 EPCglobal에서 제안하는 Discovery Service를 중심으로 다수의 연구가 진행 중이다. 하지만 객체의 상태변화를 모니터링 하는 기능을 제공하지 않으며, 객체의 이력정보를 특정 서버에서 취합하여 관리해야 한다는 단점이 있다. 이 문제를 해결하기 위해서는 객체에 대한 상태정보를 제공하기 위한 모델이 필요하며 RFID 객체의 URL을 나타낼 수 있는 식별자 역시 필요하다. 이러한 문제점을 보완하고자 SIP 이벤트 통지 및 프레즌스 모델을 활용하여 RFID 객체의 상태정보를 Track & Trace하기 위한 새로운 방법을 제안한다. 본 논문에서는 객체의 URL을 얻기 위해서 기존 ONS를 그대로 활용하되 성능저하가 없도록 하여 backward-Compatibility를 충족하도록 하였다. 또한 이렇게 얻어진 URL을 이용하여 RFID 객체 혹은 객체의 상태정보를 관리하고 있는 요소에 접근하기 위해 SIP 프로토콜을 사용하도록 하여 객체관리를 위해 개방형 인터페이스를 사용하였다. SIP 메시지 조합을 통해 객체의 이력정보를 얻을 때 DS와 같은 추가적 요소 없이도 객체의 Track을 Trace가 가능하게 하였다. 이 방식을 활용하여 지금까지와는 달리 분산취합구조를 이용하여 객체에 대한 상세이력정보 및 모니터링을 제공할 수 있도록 하였다.

Atomistic Simulation of Sintering Mechanism for Copper Nano-Powders

  • Seong, Yujin;Hwang, Sungwon;Kim, See Jo;Kim, Sungho;Kim, Seong-Gon;Kim, Hak Jun;Park, Seong Jin
    • 한국분말재료학회지
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    • 제22권4호
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    • pp.247-253
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    • 2015
  • The sintering mechanisms of nanoscale copper powders have been investigated. A molecular dynamics (MD) simulation with the embedded-atom method (EAM) was employed for these simulations. The dimensional changes for initial-stage sintering such as characteristic lengths, neck growth, and neck angle were calculated to understand the densification behavior of copper nano-powders. Factors affecting sintering such as the temperature, powder size, and crystalline misalignment between adjacent powders have also been studied. These results could provide information of setting the processing cycles and material designs applicable to nano-powders. In addition, it is expected that MD simulation will be a foundation for the multi-scale modeling in sintering process.

An Analysis of Femoral Bone Remodeling Using Topology Optimization Method

  • Choi J. B.
    • 대한의용생체공학회:의공학회지
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    • 제26권6호
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    • pp.365-372
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    • 2005
  • Topology optimization method has a great advantage and capability over a conventional shape optimization technique because it optimizes a topology as well as a shape and size of structure. The purpose of the present study, using topology optimization method with an objective function of minimum compliance as a mechanism of bone remodeling, is to examine which shape factors of femur is strongly related with the curvature of femoral shaft. As is expected, the optimized curvature increased definitely with neck angle among the shape factors and showed a similar trend with the measured curvature to neck angle. Therefore, the topology optimization method can be successfully applied in the analysis of bone remodeling phenomenon in the subsequent studies.

저속 후방 추돌에 따른 승객 거동 현상 해석용 모델 개발 (Development of a Model for the Analysis of Occupant Response subjects in Low-Speed Rear-End Collision)

  • 김희석;김영은
    • 한국자동차공학회논문집
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    • 제8권3호
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    • pp.139-150
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    • 2000
  • Although a number of neck injuries are generated, the data which quantify the kinematic response of the human head and cervical spine in low-speed rear-end automobile collisions is very limited. On this problem, just few in vitro experimental research or some experimental research using dummy on neck injury by rear-end collision was conducted, thus systematic research is requested on full scale injury mechanism. An occupant model for the response of the occupant subject to rear-end collision using commercial dynamics package DADS was developed. Developed model shows more close agreement with the experimental data compared with the MADYMO simulation results for the cases of ${\delta}V=16$ kph in sled test. For the case of ${\delta}V=8$ kph and 33.5 kph with production seat, model also shows its reliable response compared with experimental results using Hybrid III and Hybird III with RID.

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눈동자 운동이 가능한 컬러 스테레오 머리-눈 시스템의 개발 (Development of a Color Stereo Head-Eye System with Vergence)

  • 황보명;유범재;오상록;이종원
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 G
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    • pp.2370-2372
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    • 1998
  • Recently we have developed an active stereo head-eye system with vergence, name it KIST HECter(Head-Eye System with Colored Stero Vision), based on the analysis of human's neck and eye motion at visual behavior. Our HECter is a five degree-of-freedom system composed of pan and tilt motion in neck part and independent vergence motion of binocular cameras and commonly shared elevation axis in eye part. And stereo vision Provides two color image, which are processed by powerful each TMS32080 vision board. The shape and size are designed to be almost same as human face. The ability to vergence has significant importance and gives many beneficial merits. On its mechanical implementation we adapt a non-parallelogram 4-bar linkage mechanism since it provides high accuracy in transfering motion and enables compact and flexible design.

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A case report of "minor" trauma leading to a major disability: whiplash-associated dysphagia, dysphonia, and dysgeusia

  • Schattner, Ami;Glick, Yair
    • Journal of Trauma and Injury
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    • 제35권2호
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    • pp.115-117
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    • 2022
  • "Whiplash"-type injuries are commonly encountered and often cause neck pain, neck stiffness, and headaches. However, these injuries can have rare and poorly recognized complications, such as the development of a prevertebral hematoma leading to acute respiratory failure in the emergency department, followed by severe, life-threatening dysphagia and recurrent aspirations. In the patient described herein, a whiplash injury was accompanied by vocal cord paralysis and dysphonia (vagus nerve), dysgeusia (glossopharyngeal nerve, vagus nerve), and upper esophageal spasm (cricopharyngeal muscle, vagus nerve). It is unlikely that this was a complication of cervical fusion surgery. Instead, a combined stretch-induced lower cranial nerve injury, possibly on the exit of these nerves through the jugular foramen, seems to be a likely, but underappreciated mechanism occurring in rare instances of whiplash injuries.

두경부 편평상피세포암의 p53단백과 PCNA 및 Ki-67의 발현양상 (CORRELATION BETWEEN P53, PCNA AND KI-67 EXPRESSION IN HEAD NECK SQUAMOUS CELL CARCINOMA)

  • 이은진;이상한;손윤경
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제27권2호
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    • pp.142-149
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    • 2001
  • To investigate the correlation between the clinical features and the expression of p53, PCNA, and Ki-67 of the head neck squamous cell carcinoma, immunohistochemicalstaining of p53, PCNA, and Ki-67 on the paraffin embedded tissue blocks of 116 surgically removed specimens were done. The staining intensity was divided as grade 1 to grade 3 and the results were statistically analysed. 1. The positive reation rates of cell proliferation markers (PCNA and Ki-67) were higher than that of p53. There was significant correlations of the PCNA and Ki-67 expression but there was no significant correlations between p53 and PCNA or p53 and Ki-67. 2. There were no significant correlation between the expression of p53, PCNA and Ki-67 and tumor site or tumor size. 3. There was no significant differences in the positive response according to the nodal status. The node metastasis groups revealed that higher proportion of grade 3 staining of PCNA and Ki-67 than node negative group. From the above results it is concluded that p53 and cell proliferation markers PCNA and Ki-67 might have their unique mechanism involving in the growing and progression of tumor. Overexpression of p53 does not appear to represent an independent prognostic marker in head neck squamous cell carcinoma.

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