• Journal of Yeungnam Medical Science
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• 제17권1호
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• pp.12-20
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• 2000

The memory of pain can be more damaging than its initial experience. Several factors arc related the directions of pain memory: current pain intensity, emotion, expectation of pain, and peak intensity of previous pain. The possible mechanisms behind the memory of pain are neuroplastic changes of nervous system via peripheral and central sensitization. Peripheral sensitization is induced by neurohumoral alterations at the site of injury and nearby. Biochemicals such as K+, prostaglandins, bradykinin, substance P, histamine and serotonin, increase transduction and produce continuous nociceptive input. Central sensitization takes place within the dorsal horn of spinal cord and amplifies the nociceptive input from the periphery. The mechanisms of central sensitization involve a variety of transmitters and postsynaptic mechanisms resulting from the activations of NMDA receptors by glutamate. and activation of NK-1 tachykinnin receptors by substance-P and neurokinnin. The clinical result of peripheral and central sensitization is hyperalgesia, allodynia, spontaneous pain, referred pain, or sympathetically maintained pain. These persistent sensory responses to noxious stimuli arc a form of memory. The hypothesis of preemptive analgesia is that analgesia administered before the painful stimulus will prevent or reduce subsequent pain and analgesic requirements in comparison to the identical analgesic intervention administered after the painful stimulus, by preventing or reducing the memory of pain in the nervous system. Conventionally, pain management was initiated following noxious stimuli such as surgery. More recently, however many have endorsed preemptive analgesia initiated before surgery. Treatments to control postsurgical pain are often best started before injury activates peripheral nociceptors and triggers central sensitization. Such preemption is not achieved solely by regional anesthesia and drug therapy but also requires behavioral interventions to decrease anxiety or stress. Although the benefit of preemptive analgesia may not be obvious in every circumstance, and in many cases may not sufficient to abolish central sensitization, it is an appropriate and human goal of clinical practice.

• 인문언어
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• 제1권2호
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• pp.67-90
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• 2001

In the past few years, a trend has emerged emphasizing the interdisciplinary relationship between cultural and literary studies, and "memory" has been suggested as the central theme in this trend. According to Aleida and Jan Assmann, "memory" as collective memory (not individual recollection) has various functions and forms, of which communicative memory and cultural memory occupy opposite poles of a central axis. Whereas communicative memory relates to the living past shared among contemporaries, cultural memory relates to "recollected history" rather than factual history. Cultural memory finds transmission through symbolic media such as myths, festivities, and literary works. Literary works preserve critical and living memories as opposed to forgotten memories. In other words, literature should be better read as "criticism and memory" than "imitation and preservation." Works of literature are characterized by a turning away from repetition toward representation-the process of "making present" of what is past.

• Earthquakes and Structures
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• 제23권2호
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• pp.207-219
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• 2022

Seismic response control has always been a grave concern with the damage and collapse of many buildings during the past earthquakes. While there are several existing techniques like base isolation, viscous damper, moment-resisting beam-column connections, tuned mass damper, etc., many of these are succumbing to either of large displacement, near-fault, and long-period earthquakes. Keeping this viewpoint, extensive research on the application of smart materials for seismic response control of buildings was attempted during the last decade. Shape Memory Alloy (SMA) with its unique properties of superelasticity and shape memory effect is one of the smart materials used for seismic control of buildings. In this paper, an exhaustive review has been compiled on the seismic control applications of SMA in buildings. Unique properties of SMA are discussed in detail and different phases of SMA along with crystal characteristics are illustrated. Consequently, various seismic control applications of SMA are discussed in terms of performance and compared with prevalent base isolators, bracings, beam-column connections, and tuned mass damper systems.

• Natural Product Sciences
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• 제11권4호
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• pp.189-192
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• 2005

Anti-amnestic activities of Korean red ginseng (Ginseng Radix Rubra) and Crude drug-combined preparations (RGCDP-1, RGCDP-2, and RGCDP-3) were evaluated by the animal experiment. RGCDP-1 and RGCDP-2 were prepared based on Korean folk prescriptions, 'Chongmyongtang' and 'Guibitang', respectively, while RGCDP-3, by a combination of both. Among the three preparations, RGCDP-3 was found to show the most potent anti-amnestic activity as evaluated by the passive avoidance test with mice, indicating synergistic action by combined effect of RGCDP-1 and RGCDP-2.

• 대한한의학회지
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• 제23권2호
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• pp.125-138
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• 2002

Learning and memory are essential requirements for every living organism in order to cope with environmental demands, and cholinergic systems are known to be involved in learning and memory. Scutellaria baicalensis (SB) and Gastrodia elata (GE) as a traditional Oriental medicine have been clinically used to treat or prevent memory deficits, including Alzheimer's disease. In the present study, we investigated the effects of SB and GE on learning and memory in the Morris water maze task and the central cholinergic system of the rats with excitotoxic medial septum lesions. In the water maze test, the animals were trained to find a platform at a fixed position over 6 days and then received a 60-s probe trial in which the platform was removed from the pool on the 7th day. Ibotenic lesion of the medial septum (MS) impaired their performance in the maze test (latency of acquisition test on the 3rd day, $27.6{\pm}$4.4 sec vs. $61.7{\pm}17.7$ sec; retention test, $7.9{\pm}1.3%$ vs. $5.7{\pm}1.0%$: sharn vs. ibotenic lesioned groups, respectively) and reduced choline acetyltransferase (ChAT) - immunoreactivity in the MS and the hippocarnpus, which is a marker for degeneration of the central cholinergic system (number of cells, $21.1{\pm}1.1$ vs. $13.2{\pm}1.3$: sham vs. ibotenic lesioned group). Daily administrations of SB (100mg/kg, p.o.) and GE (100mg/kg, p.o.) for 21 consecutive days produced significant reversals of ibotenic acid-induced deficit in learning and memory. These treatments also reduced the loss of cholinergic immunoreactivity in the MS and the hippocarnpus induced by ibotenic acid. These results demonstrated that SB and GE ameliorated learning and memory deficits through effects on the central nervous system, partly through effect on the acetylcholine system. Our studies suggest an evidence of SB and GE as treatment for Alzheimer's disease.

• 대한한의학회지
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• 제29권5호
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• pp.67-76
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• 2008

Objectives : Amnesia is theloss or impairment of memory, caused by physical injury, disease, drugs, or emotional trauma. Recently, the average life span is increasing, while at the same time, the incidence of dementia-like diseases in conjunction with amnesia are also increasing. Therefore learning and memory are very important issues in modern society. Ancient Korean physicians used several herbs to treat dementia and these herbal effects were described in Korean herbal books. Among them are some reports on several cognitive-enhancing herbs which have since been shown to improve dementia in recent pharmacological studies, such as Panax ginseng; however, the facilitatory effects of many Korean cognitive-enhancing herbs on learning and memory are limited. Learning and memory are essential requirements for every living organism in order to cope with environmental demands; cholinergic systems are known to be involved in learning and memory. Methods : In this study, the effects of Acori graminei rhizoma (AGR, 石菖蒲) on learning and memory were investigated by Morris water maze, eight-arm radial maze, and the effects on the central cholinergic system of rats injected with scopolamine. Results : In the water maze, the experimental animals were trained to find a platform in a fixed position for 6 days and then received a 60 sec probe trial in which the platform was removed from the pool on the 7th day. In the eight-arm radial maze, the animals were tested four times per day for 6 days. Scopolamine impaired performance of the maze tests and reduced activity of acetylcholinesterase (AchE) in the hippocampus, which is a marker for the central cholinergic system. There were significant reversals from the scopolamine-induced deficits on learning and memory in these tests, through daily administrations of AGR (100 mg/kg, p.o.) over 14 consecutive days. These treatments also reduced the loss of cholinergic activity in the hippocampus induced by scopolamine. Conclusions : These results demonstrated that AGR ameliorated learning and memory deficits by affecting the central acetylcholine system.

• Archives of Pharmacal Research
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• 제28권6호
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• pp.691-698
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• 2005

Phlorotannins, the polyphonic compounds found in brown Eisenia and Ecklonia algae, have several pharmacologically beneficial effects such as anti-inflammation. In addition, our recent data show that these compounds may improve the cognitive functions of aged humans suggesting the potential ability to enhance memory in several neurodegenerative disorders. To examine the experimental hypothesis that two effective components of Ecklonia cava, dieckol and phlorofucofuroeckol (PFF), have memory-enhancing abilities, both were administered orally to mice before a passive avoidance test. The repeated administration of either dieckol or PFF dose-dependently reduced the inhibition of latency by the administration of ethanol. To investigate the mode of memory-enhancing actions, the levels of major central neurotransmitters in three different regions (striatum, hippocampus, and frontal cortex) of the mouse brain were measured. The levels of some of the neurotransmitters were significantly changed by ethanol. Both dieckol and PFF altered the levels of some neurotransmitters modified by the ethanol treatment. It is noteworthy that both dieckol and PFF increased the level of acetylcho-line, and they exerted anticholinesterase activities. Overall, the memory-enhancing abilities of dieckol and PFF may result from, at least in part, the increment of the brain level of acetylcho-line by inhibiting acetylcholinesterase.

• 감성과학
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• 제6권3호
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• pp.29-43
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• 2003

본 연구에서는 남성과 여성에 있어서 정서적 자극에 대한 기억이 다른지를 알아보고자 하였다. 또한 제시되는 자극의 기억을 측정할 것이라는 기억지시문을 주고, 또한 자극제시 후 곧바로 자유회상의 방법으로 기억을 측정함으로써 정서적 자극으로 유발된 정서의 표현을 조절할 필요성을 가능한 최소화시켰다. 그리고 남성과 여성의 정서적 자극과 중성적 자극에 대한 기억을 측정함으로써 선행사건초점 정서조절 과정에 의해 남성들의 정서적 자극에 대한 기억이 손상됨을 밝히고자 하였다. 전체적으로 여성들이 남성들보다 제시된 자극에 대하여 더 많이 기억하고 있었으며, 특히 중성적 자극보다 정서적 자극에 대해 남성들보다 더 많은 내용을 회상하였다. 회상내용을 중심적 요소에 대한 기억과 지엽적 요소에 대한 기억으로 나누어 남녀 차이를 분석해본 결과, 여성들은 정서적 자극의 중심적 요소에 대하여 중성적 자극보다 더 많이 기억하였으나 남성들은 정서적 자극과 중성적 자극에 대한 중심적 요소에 대한 기억차이가 나타나지 않았다.

• Molecules and Cells
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• 제23권3호
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• pp.259-271
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• 2007

Investigation of molecular and cellular mechanisms of synaptic plasticity is the major focus of many neuroscientists. There are two major reasons for searching new genes and molecules contributing to central plasticity: first, it provides basic neural mechanism for learning and memory, a key function of the brain; second, it provides new targets for treating brain-related disease. Long-term potentiation (LTP), mostly intensely studies in the hippocampus and amygdala, is proposed to be a cellular model for learning and memory. Although it remains difficult to understand the roles of LTP in hippocampus-related memory, a role of LTP in fear, a simplified form of memory, has been established. Here, I will review recent cellular studies of LTP in the anterior cingulate cortex (ACC) and then compare studies in vivo and in vitro LTP by genetic/pharmacological approaches. I propose that ACC LTP may serve as a cellular model for studying central sensitization that related to chronic pain, as well as pain-related cognitive emotional disorders. Understanding signaling pathways related to ACC LTP may help us to identify novel drug target for various mental disorders.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 심포지엄 논문집 정보 및 제어부문
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• pp.153-155
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• 2004

In this paper, we design the memory tester chip playing an important role in the memory tester as central parts. Memory tester has the sixteen inner instructions to control the test sequence and the address and data signals to DUT. These instructions are saved in memory with each block such as sequencer and pattern generator. Sequencer controls the test sequence according to instructions saved in the memory. And Pattern generator generates the address and data signals according to instructions saved in the memory, too. We can use these chips for various functional test of memory.