• Journal of Nutrition and Health
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• 제10권2호
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• pp.5-11
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• 1977

The mature human braun contains over 10 billion nerve cells (neurons), whose functions are directly related to the acquisition, transfer, processing, analysis, and utilization of all the information. There are also billions of glial cells, which serve primarily to support and to maintain the integrity of the neuron network and to synthesize an essential fatty strucfure, myelin. In the human brain DNA content therefore cell number rises rapidly until birth and then more slowly until $5{\sim}6$ months of age, when it reaches a maximum. While glial cells may be replaced, the more important nerve cell neurons can never be replaced once they are formed. Humans are born with their full complement of neurons and every neuron is as old as each individual. Thus prenatal malnutrition can seriously affect a person's entire life by severely inhibiting the production of neurons before birth.It has been demonstrated that in humans severe malnutrition during the fetal period and in infancy is associated with intellectual impairment. Severely malnourished children have brains smaller than average size and have been found to have $15{\sim}20%$ fewer brain cells than wellnourished childen. There is growing body of literature pointing to malnutrition as a cause of abnormal behavior as evidence that suggests these abnormalities may produce chromosomal damage that may persist forever. Although cognitive development in children is affected by multiple environmental factors, nutrition certainly deaerves more attention than it has received.

• The Journal of Korean Physical Therapy
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• 제33권2호
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• pp.106-113
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• 2021

Purpose: This study examined the effectiveness of action observation training (AOT) and mirror therapy in improving the electroencephalograms (EEG) of stroke patients. Methods: Patients were allocated randomly to three groups: an action observation training with activity (AOTA) group (n=12), a mirror therapy with activity (MTA) group (n=11), and an AOT-only group (n=12). All groups received conventional physiotherapy in five 60-minute sessions over six weeks. The AOTA, MTA, and AOT groups practiced AOTA, MTA, and AOT, respectively, in three 30-minute sessions over six weeks. The differences between the pre- and post-treatment EEGs were assessed using a paired t-test. Comparisons between the groups were performed using one-way ANOVA. Results: The participants in the AOTA and MTA groups showed significant improvement in the EEG. AOTA improved the alpha waves of the prefrontal, temporal, and parietal lobes significantly (p<0.05). MTA improved the alpha waves of the temporal lobe significantly (p<0.05). AOT did not result in significant improvement Conclusion: AOTA and MTA improve stroke patients' EEGs. Mirror neuron activation combined with conventional stroke physiotherapy promotes motor recovery and functioning. The effect is enhanced when the actions are executed after observation. Further research into mirror neuron activation will be needed to develop methods to improve the EEGs of stroke patients.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2020년도 추계학술발표대회
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• pp.793-795
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• 2020

본 논문에서는 스파이킹 뉴론(Spiking Neuron)들이 쿨롱에너지 포텐셜 (Coulomb Energy Potential)을 가지는 스파이킹 신경회로망에서의 학습알고리즘을 일반화하여 구간연산(Interval Arithmetic)의 학습이 가능한 학습알고리즘을 제안한다. 제안하는 학습알고리즘은 입력 데이터로서 구간(Interval) 데이터와 포인트(Point) 데이터를 모두 학습 할 수 있는 일반화된 학습알고리즘으로서 간단한 컴퓨터 시뮬레이션을 통하여 범위(Lower bound & Upper bound)를 가지는 구간데이터와 포인트데이터의 통합적인 학습이 가능하고 전문가시스템(expert system)에서의 "don't care attributes"의 학습 등에도 활용이 가능함을 보인다.

• 한국정보통신학회논문지
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• 제20권11호
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• pp.2193-2198
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• 2016

본 연구에서는 뉴런이 지니는 기능 및 결합구조를 모사하여 $3{\times}3$ 배열의 기능별로 분리시킨 후 디지털회로에서 동작 중 발생할 수 있는 일시적 또는 영구적인 오류 위치를 정확히 찾아내어 복구 시키는 알고리즘을 제안한다. 결합된 세포에서 어느 특정 일부분이 문제가 발생할 경우 그 기능을 다른 세포로 분화되어 동일 기능을 수행하며 오류가 발생한 세포는 주변 세포에 의해 사멸시키는 단계를 거친다. 이런 세포가 지니는 기능 및 구조를 디지털 회로내부에 기능 블록구조로 설계하여 알고리즘을 제안하였다. 본 연구에서 고려한 1번 블록의 4번 모듈이 오류가 발생했을 경우가로 방향에 대한 전체 모듈번호에 대한 합, 세로 방향에 대한 전체 모듈 번호 합, 대각선 방향에 대한 전체 모듈 번호의 합을 이용하여 쉽게 그 위치를 찾을 수 있었다.

• 한국전기전자재료학회논문지
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• 제11권1호
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• pp.7-11
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• 1998

In this paper, a new synapse cell with nonvolatile SONOS semiconductor memory device is proposed and it's fundamental function electronically implemented SONOS NVSM has shown characteristics that the memory value, synaptic weights, can be increased or decreased incrementally. A novel SONOS synapse is used to read out the stored analog value. For the purpose of synapse implementation using SONOS NVSM, this work has investigated multiplying characteristics including weight updating characteristics and neuron output characteristics. It is concluded that SONOS synapse cell has good agreement for use as a synapse in artificial neural networks.

• Tuberculosis and Respiratory Diseases
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• 제39권6호
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• pp.502-510
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• 1992

연구배경 : Neuron specific enolase (NSE)는 뇌조직의 신경원에서 처음 발견된 당분해 효소이며, APUD 세포 및 신경내분비계에도 존재하는 것으로 알려졌다. 소폐포폐암은 신경내분비세포 및 APUD 세포와 많은 공통점을 가지고 있다. 따라서 NSE 항체를 사용하는 면역조직화학 염색과 혈청내 NSE 농도측정은 신경내분비 분화를 하는 폐종양의 표지자로서 사용될 수 있으며 소세포폐암의 진단에 유용할 수 있다. 방법 : 소세포폐암으로 진단받은 22명과 대조군으로는 비소세포폐암환자 21명을 대상으로 하였으며 생검조직에서 NSE 항체를 이용한 면역조직화학염색을 시행하고 환자의 혈청에서 방사면역측정법으로 NSE 농도를 측정하였다. 결과: 1) NSE 항체를 이용한 면역조직화학염색 NSE 항체를 이용한 면역조직화학영색에서 소세포폐암군 환자는 18명중 9명에서 양성 반응을 보였으며, 비소세포폐암 환자중 면역조직화학염색을 시행한 16명중 5명에서 양성 반응을 보였다. 2) 방사면역 측정법에 의한 혈청 NSE농도 측정 비소세포폐암군의 혈청 NSE평균치는 $11.79{\pm}4.47\;ng/ml$이었으며 소세포폐암군의 혈청 NSE치는 개인차가 심하기는 하였으나(6.01~361.4 ng/ml) 그 평균치는 $59.30{\pm}77.88\;ng/ml$으로 두 군 사이에는 유의한 차이가 있었다. 소세포폐암환자중 limited disease군의 혈청 NSE 평균치는 $20.19{\pm}12.91\;ng/ml$이었으며, extended disease군의 혈청 NSE치는 역시 개인차가 심하기는 하였으나(17.15~361.44 ng/ml) 그 평균치는 $91.9{\pm}94.2\;ng/ml$로 두 군 사이에 유의한 차이를 보였다. 정상인에서의 혈청 NES 농도는 측정하지 않았으나 대조군인 비소세포폐암군환자 평균+2x표준편차인 20 ng/ml을 기준으로 할 때 소세포폐암환자 22명중 16명(73%)에서 증가된 소견을 보였고 이중 limited disease는 50%(5/10), extended disease는 92% (11/12)에서 증가되었으며, 비소세포암 환자중에서는 1명(1/21)만이 증가된 소견을 보였다. NSE 혈청농도와 면역조직화학염색 정도를 비교시 소세포폐암군과 비소세포폐암군 모두에서 유의한 상관관계를 보이지 않았다. 결론 : 혈청 NSE농도측정은 소세포폐암환자에서 암표지자로서 유용한 방법이 될 수 있을 것으로 사료되며 항 NSE 항체를 이용한 생검조직의 면역조직화학염색은 분화가 나빠 고식적인 현미경적 소견만으로는 소세포암과 비소세포암과의 강벌이 어려운 경우 정확한 조직유형 결정과 신경내분비 기원을 뵈이는 폐암의 진단에 도움을 줄 수 있을 것으로 사료된다.

• The Korean Journal of Pain
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• 제11권1호
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• pp.23-29
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• 1998

Background: The present study was conducted to investigate effects of microinjection of bicuculline, GABA-A receptor antagonist, into the brain stem nuclei on the dorsal horn neuron responsiveness in rats with an experimental peripheral neuropathy. Methods: An experimental neuropathy was induced by a unilateral ligation of L5~L6 spinal nerves of rats. After 2~3 weeks after the surgery, single-unit recording was made from wide dynamic range (WDR) neurons in the spinal cord dorsal horn. Results: Responses of WDR neurons to both noxious and innocuous mechanical stimuli applied to the somatic receptive fields were enhanced on the nerve injured side. These enhanced responsiveness of WDR neurons were suppressed by microinjection of bicuculline into periaqueductal gray(PAG) or nucleus reticularis gigantocellularis(Gi). A similar suppression was also observed when morphine was microinjected into PAG or Gi. Suppressive action by Gi-bicuculline was reversed by naloxonazine, ${\mu}$-opioid receptor antagonist, microinjected into PAG whereas PAG-bicuculline induced suppression was not affected by naloxonazine injection into Gi. Gi-bicuculline induced suppression were reversed by a transection of dorsolateral funiculus(DLF) of the spinal cord. Conclusions: The results suggest that endogenous opioids, via acting on GABAergic interneurons in PAG and Gi, may be involved in the control of neuropathic pain by activating the descending inhibitory pathways that project to the spinal dorsal horn through DLF to inhibit the responsiveness of WDR neurons.

• 대한수의학회지
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• 제40권2호
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• pp.275-282
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• 2000

Substantia nigra is known to highly express glibenclamide binding site, a protein associated to ATP-sensitive $K^{+}$ ($K_{ATP}$) channel in the brain. However, the functional expression of $K_{ATP}$ channels in the area is not yet known. In this work, we attempted to estimate the functional expression of $K_{ATP}$ channels in neurons of the substantia nigra pars compacta (SNC) in young rats using slice patch clamp technique. Membrane properties and whole cell currents attributable to $K_{ATP}$ channel were examined by the current and voltage clamp method, respectively. In SNC, two sub-populations of neurons were identified. Type I (rhythmic) neurons had low frequency rebound action potentials ($4.5{\pm}0.25Hz$, n=75) with rhythmic pattern. Type II (phasic) neurons were characterized by faster firing ($22.7{\pm}3.16Hz$, n=12). Both time constants and membrane capacitance in rhythmic neurons ($34.0{\pm}1.27$ ms, $270.0{\pm}11.83$ pF) and phasic neurons ($23.7{\pm}4.16$ ms, $184{\pm}35.2$ pF) were also significantly different. The current density of $K_{ATP}$ channels was $6.1{\pm}1.47$ pA/pF (2.44~15.43 pA/pF, n=8) at rhythmic neurons of young rats. Our data show that in SNC there are two types of neurons with different electrical properties and the density of $K_{ATP}$, channel of rhythmic neuron is about 600 channels per neuron.

• Annals of Clinical Neurophysiology
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• 제5권1호
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• pp.21-26
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• 2003

Background & Objectives: Hyperexcitablity of motor system is a well-established characteristic pathophysiologic finding of amyotrophic lateral sclerosis (ALS). Whereas little is known about the source of excitability according to the progression of the disease. We evaluated the excitability and its source in advanced ALS patients using transcranial magnetic stimulation (TMS). Meterial & Methods: Motor evoked potentials (MEP) by TMS were recorded for abductor pollicis brevis muscles in 20 patients, 11 men and 9 women, with ALS. Mean age was $54.2{\pm}12.1years$, and mean disease duration was $13.9{\pm}13.4years$. Serial magnetic stimulations were applied to get the parameters; excitability threshold (ET), amplitude and latency of MEP. We also had a facilitated MEP (fMEP). Results: The parameters were analyzed according to the clinical settings. ET was higher in ALS(mean $63.5{\pm}18.1$) than normal control (mean $46.0{\pm}8.4$, p<0.01). Amplitudes of MEP were reduced in ALS ($2.6{\pm}3.6mV$; control $6.5{\pm}3.1mV$, p<0.01). Duration of the disease and ET showed significant inverse correlation (Spearson correlation coefficient = -0.57, p<0.01). Duration of the disease and fMEP/MEP ratio showed less but also significant inverse correlation (Spearson correlation coefficient, r = -0.52, p < 0.05). Conclusions: Lower ET in advanced ALS patients, in spite of decreased fMEP/MEP ratio, may indicate the hyperexcitability of lower motor neurons in these patients. This study suggests that lower motor neurons is hyperexcitable due to upper motor neuron dysfunction at advanced stage.

• 전자공학회논문지B
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• 제29B권11호
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• pp.85-92
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• 1992

In this paper we propose a diffusion neural network model. In this model, each excitatory and inhibitory neuron has the capability of diffusing external excitations. We show that this model can be used for the detection of intensity changes of an input image. The relations between the diffusion coefficient, the iteration number of diffusion, and the detected spatial frequency are analyzed. The calculation time is reduced than that of a LOG(a Laplacian of a Gaussian) method.