• 제목/요약/키워드: nerve system

검색결과 863건 처리시간 0.026초

세포-신경계-혈류역학 시스템 통합모델에 의한 심장역학 분석 (Computational analysis of heart mechanics using a cell-autonomic nerve control-hemodynamic system coupled model)

  • 전형민;심은보
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회B
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    • pp.2941-2946
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    • 2007
  • A model of the cardiovascular system coupling cell, hemodynamics and autonomic nervecontrol function is proposed for analyzing heart mechanics. We developed a comprehensive cardiovascular model with multi-physics and multi-scale characteristics that simulates the physiological events from membrane excitation of a cardiac cell to contraction of the human heart and systemic blood circulation and ultimately to autonomic nerve control. Using this model, we delineatedthe cellular mechanism of heart contractility mediated by nerve control function. To verify the integrated method, we simulated a 10% hemorrhage, which involves cardiac cell mechanics, circulatory hemodynamics, and nerve control function. The computed and experimental results were compared. Using this methodology, the state of cardiac contractility, influenced by diverse properties such as the afterload and nerve control systems, is easily assessed in an integrated manner.

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랫드의 신경조직에 미치는 Tellurium의 독성에 관한 연구 (A Study on the Neurotoxic Effects of Tellurium on Murine Nervous System)

  • 김기석;정문호
    • 한국환경보건학회지
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    • 제24권3호
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    • pp.35-40
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    • 1998
  • This study was conducted to examine the pathological changes of rat peripheral nervous system during exposure to tellurium known to be a demyelinating agent by using teasing nerve fiber method and quantitative light microscopic analysis by image analyzer. The pellet containing 1.2% of tellurium were fed for 3, 5, 7, 9, 13 days to male wistar rats (21 days old) and then neurologic symptom and the feature of nerve fiber myelination were studied. From this study, following results were obtained. In 3 days treated group, it showed various neurologic symptom and teased nerve fiber showed slight irregularity of the myeline sheath. In 5 days and 7 days treated groups, it showed the segmental demyetination in larger size fiber and widening of nodes of ranvier. In 9 days and 13 days treated groups, the remyelinated fibers were observed and it was generally small in size. We consequently suggest that teasing nerve fiber method and quantitative analysis of nerve fiber were useful pathologic screening method of neurotoxicity of the peripheral nervous system.

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A potential role of Schwann cells in spinal nerve roots in autoimmune central nervous system diseases

  • Moon, Changjong;Lee, Yongduk;Shin, Taekyun
    • 대한수의학회지
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    • 제44권4호
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    • pp.483-486
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    • 2004
  • The expression of nestin and vimentin in the spinal nerve roots of rats with experimental autoimmune encephalomyelitis (EAE) was studied to ascertain whether Schwann cells in the peripheral nerves respond to acute central nervous system autoimmune injury. Immunohistochemistry demonstrated that nestin was constitutively expressed in the dorsal roots of spinal nerves in control rats; its expression was enhanced in the spinal nerve roots of rats with EAE. Vimentin expression was weak in control rat spinal nerve roots, and it was increased in the dorsal roots of rats with EAE. It is postulated that normal animals have multipotent progenitor cells that constitutively express nestin and vimentin in the spinal nerve roots. In response to an injury of the central nervous system, these multipotent Schwann cells are activated in the spinal nerve roots through the expression of the intermediate filament proteins vimentin and nestin.

비강의 삼차신경 화학수용 (Nasal Trigeminal Chemoreception)

  • 김병국;김지선
    • Korean Journal of Otorhinolaryngology-Head and Neck Surgery
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    • 제61권11호
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    • pp.567-572
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    • 2018
  • The sensory function of the trigeminal nerve is to provide tactile, proprioceptive, and nociceptive afference by chemical stimulation. Various physical responses of the trigeminal nerve to stimuli help to defend against harmful substances. Recently, many studies have been conducted on solitary chemoreceptor cells innervated by trigeminal nerve. Most volatile organic compounds stimulate both the olfactory and trigeminal nervous systems. In general, the trigeminal nervous system is less sensitive than the olfactory nervous system. Studies have shown that sensation of the trigeminal nerve by chemical stimulation results in inhibition of olfaction. This indicates that the olfactory and trigeminal nerves interact with each other in the central nervous system. It is important to study various noxious stimuli acting on the trigeminal nerve in modern society where environmental concerns are intensifying.

Sural nerve grafts in subacute facial nerve injuries: a report of two cases

  • Jiwon Jeong;Yongjoon Chang;Kuylhee Kim;Chul Hoon Chung;Soyeon Jung
    • 대한두개안면성형외과학회지
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    • 제25권2호
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    • pp.99-103
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    • 2024
  • Because facial nerve injuries affect the quality of life, leaving them untreated can have devastating effects. The number of patients with traumatic and iatrogenic facial nerve paralysis is considerably high. Early detection and prompt treatment during the acute injury phase are crucial, and immediate surgical treatment should be considered when complete facial nerve injury is suspected. Symptom underestimation by patients and clinical misdiagnosis may delay surgical intervention, which may negatively affect outcomes and in some cases, impair the recovery of the injured facial nerve. Here, we report two cases of facial nerve injury that were treated with nerve grafts during the subacute phase. In both cases, subacute facial nerve grafting achieved significant improvements. These cases highlight surgical intervention in the subacute phase using nerve grafts as an appropriate treatment for facial nerve injuries.

Intraoperative Neurophysiological Monitoring in Cerebello Pontine Angle Tumor

  • Park, Sang-Ku
    • 대한임상검사과학회지
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    • 제46권1호
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    • pp.38-45
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    • 2014
  • Intraoperative Neurophysiological Monitoring (INM) inspection has a very important role. While preserving the patient's neurological function be sure to safe surgery, neurological examination should thank. Cerebello pontine angle tumor surgery, especially in the nervous system is more important to the meaning of INM. In cochlear nerve, facial nerve, trigeminal nerve, which are intricate brain surgery, doctors are only human eye and brain to the brain that it is virtually impossible to distinguish the nervous system. They receives a lot of help from INM. In this paper, we examined six kinds broadly. First, the methods of spontaneous EMG and Free-running EMG, which can instantly detect a damage inflicted on a nerve during surgery. Second, methods of triggered EMG and direct nerve electrical stimulation, which directly stimulate a nerve using electricity to distinguish between nerves and brain tumors. Third, the method of knowing a more accurate neurologic status by informing neurological surgeons about Free-running EMG wave forms that are segmetalized into four. Fourth, three ways of knowing when a patient will be awaken from intraoperative anesthesia, which happens due to a weak anesthetic. Fifth, a method of understanding the structures of a brain tumor and a facial nerve as five dividend segments. Sixth, comparisons between cases normal facial nerve recovery and occurrence of a facial nerve paralysis during the postoperative course.

미주신경 자극을 위한 새로운 방법 : 비침습적 TENS 적용에 대한 미주신경 자극의 치료적 효과 (New Methods of Vagus Nerve Stimulation : Therapeutic Effects of Non-Invasive Vagus Nerve Stimulation by TENS Application)

  • 권해연;문현주
    • 대한통합의학회지
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    • 제4권4호
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    • pp.77-82
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    • 2016
  • Purpose: The purpose of this study was to investigate the therapeutic effect of non-invasive vagus nerve stimulation by transcutaneous electrical nerve stimulation application on the autonomic nervous system of human body. Methods: Participants were seventeen healthy adults. Standard deviation of all normal N-N intervals(SDNN), root mean square of successive differences(RMSSD), low frequency(LF), high frequency(HF) were compared in pre and post Mean values after intervention. Data were analyzed in Wilcoxon's signed-ranks test. Results: The results of this study is that sistolic blood pressure and pulse rate decreased mean value after non-invasive vagus nerve stimulation by transcutaneous electrical nerve stimulation. High frequency, low frequency, SDNN, RMSSD increased mean value in heart rate variability after intervention. But that is not significant except for SDNN. Conclusion: Non-invasive vagus stimulation by transcutaneous electrical nerve stimulation effect on parasympathetic nerve stimulation, and then it might be effective method for autonomic nerve balance control.

동측(ipsilateral) 및 대측(contralateral) 말초신경자극이 굴근반사에 미치는 영향의 비교연구 (Effects of Ipsilateral and Contalateral Stimulation of Peripheral Nerve on Flexion Reflex in Cats)

  • 남택상;백광세;강두희
    • The Korean Journal of Physiology
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    • 제17권2호
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    • pp.169-176
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    • 1983
  • It is well known that the acupuncture has been used effectively for the relief of certain types of pain. Although the precise mechanism of action of acupuncture analgesia is unknown, it is generally accepted that their analgesic properties are related to the activation of endogenous opiate system in central nervous system. And it is suggested that pain-relieving properties of acupunture may be related to a stimulation of peripheral nerve underlying the acupuncture point on the skin. However, the efficacy of acupuncture has no relationship between the site of pain and the acupuncture point. Consequently, the present study was undertaken to investigate electroacupuncture analgesia in relation to the site of peripheral nerve stimulation. Cats were decerebrated ischemically and the flexion reflex as an index of pain was elicited by stimulating the sural nerve (20V, 0.5 msec duration) and recored as a compound action potential from the nerve innervated to the posterior biceps femoris muscle in the ipsilateral hindlimb. Bilateral common peroneal nerve and contralateral superficial radial nerve were selected as the site of peripheral nerve stimulation. For the stimulation of peripheral nerve, a stimulus of 20 V intensity, 2 msec-duration and 2 Hz-frequency was applied for 60 min respectively. The results obtained are summarized as follows: 1) Both stimulation of contralateral common peronal nerve and contralateral superficial radial nerve did not change the flexion reflex and there were no significant differences between them. 2) Stimulation of ipsilateral common peroneal nerve markedly depress the flexion reflex, the effect being reversed by naloxone application. These results suggest that stimulation of ipsilateral common peroneal nerve has the analgesic effect but both stimulation of contralteral common peroneal nerve and contralateral superficial radial nerve to the pain site where flexion reflex was elicited have no analgesic effect.

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안면신경평가기준에 따른 구안와사(口眼喎斜)의 임상관찰 (The clinical observation on Bell's palsy according to facial nerve grading system)

  • 김종인;서정철;이상훈;최도영;강성길;고형균
    • Journal of Acupuncture Research
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    • 제19권5호
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    • pp.112-123
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    • 2002
  • Background and Objective : The evaluation of facial nerve function is a complex procedure. The House-Brackmann facial nerve grading system(H-B grade)and the Yanagihara grading system(Y-system) have been recommended as universal standards for assessing the degree of facial nerve palsy. The purpose of this study is to compare the effectiveness of Y-system and H-B system and to know the advantages of each system for each stage of incomplete recovery or sequelae of facial paralysis. Materials and Methods : A comparison between H-B grade and Y-system was studied with 137 evaluations of 61 cases of incomplete recovery or sequelae of peripheral facial paralysis. Each case was graded by using H-B system as a gross system and Y-system as a regional system before treatment, after 12 weeks and 6 months Results and Conclusions : The range of score in the Y-system 0-6, 8-16, 14-22, 24-34, 32-38, 38-40 were matched with grade VI, V, IV, III, II and I in the H-B system. The percentage of H-B grade III was the greatest among 137 evaluations and y-system showed the greatest score range. H-B system is easy to use but Y-system is more objective, quantitative and convenient to use in the incomplete recovery or sequelae state.

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마이크로 컴퓨터를 이용한 운동신경전도속도 측정기의 설계와 제작에 관한 연구 (Design and Development of Motor Nerve Conduction Velocity Measuring Device Based on Microprocessor)

  • 김태욱
    • 대한의용생체공학회:의공학회지
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    • 제10권3호
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    • pp.361-364
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    • 1989
  • A PC-based motor nerve conduction velocity measuring system was designed and constructed. The system was composed with an EMG preamplifier, a stimulator, an Apple II plus microcomputer and an 8 bit AD converter. The system was primariliy intended to screen motor nerve difficulties of industrial workers. This system can acquire, store and display the waveforms of evoked potentials. The PC-based system is expected to increase the versatility and applicability as well as to reduce the system cost.

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