• Title/Summary/Keyword: Anatomical substrate

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Taxonomic Study of Amphiroa misakiensis Yendo (Rhodophyta) in Korea (한국산 홍조 난쟁이게발에 관한 분류학적 연구)

  • Choi, Do Sung
    • Journal of Integrative Natural Science
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    • v.4 no.1
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    • pp.72-78
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    • 2011
  • Morphological and anatomical characters of Amphiroa misakiensis Yendo are investigated with field materials and taxonomic accounts are given to the species. The plants grow on rocks, mussels or non-articulated corallines from the subtidal zone of Cheju island, and is characterized by recumbent and spreading habit from the substrate. The species is well defined by about 4 cm height, loosely tufted thallus with irregularly dichotomous branches, flat and irregularly broad intergeniculum in upper part, geniculum developing by cracking and sloughing of calcified cortical tissue overlying uncalcified genicular tissue, five to thirteen-tiered geniculum with unequal length, and conceptacles buried in cortices of intergeniculum. Reproductive structures in tetrasporangial, male and female plants are typical of Amphiroa. The structure and developmental patterns of conceptacles are very similar to those shown in previous studies.

Distribution of Neurons in the Lateral Reticular Nucleus Projecting to Cervical, Thoracic, and Lumbar Segments , of the Spinal Cord in the Rat

  • Lee, Hyun Sook
    • Animal cells and systems
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    • v.4 no.4
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    • pp.353-359
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    • 2000
  • Location of the neurons in the lateral reticular nucleus projecting to dorsal horn of the cervical, thoracic, or lumbar spinal cord was investigated in the rat using the technique of retrograde transport of horseradish peroxidase. The projection was bilateral with ipsilateral predominance. Neurons projecting to the cervical spinal cord were located near the medial, dorsal, and lateral perimeter of the magnocellular division of the lateral reticular nucleus, whereas cells projecting to the thoracic and lumbar spinal cord were localized in the medial and dorsal boundaries of the magnocellular division. The labeled neurons were distinctly multipolar in shape and measured approximately 10-15 $\mu m$ in their greatest transverse diameter. A few neurons were also observed in the subtrigeminal nucleus, whereas few cells were in the parbocellular division. These observations provide an anatomical substrate for the functional implication of the lateral reticular nucleus in the regulation of spinal nociceptive transmission and vascular hemodynamics via the descending pathway into the spinal cord.

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Depression and Executive Dysfunction in Stroke (뇌졸중에서 우울증과 실행기능부전에 대한 고찰)

  • Na, Kyoung-Sae;Kim, Shin-Gyeom;Lee, Soyoung Irene;Jung, Han-Yong
    • Korean Journal of Biological Psychiatry
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    • v.19 no.4
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    • pp.179-186
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    • 2012
  • Depression and executive dysfunction are common neuropsychiatric sequelae of stroke. Patients with stroke are more predisposed to depression and executive dysfunction compared to patients with similar degree of physical disability. Both depression and executive dysfunction are also associated with poor prognosis such as high mortality and delayed recovery after stroke. Complex neurobiological and anatomical mechanisms are associated with the development of depression and executive dysfunction after stroke. Activation of pro-inflammatory cytokines is thought to be associated with onset of depression, whereas injuries in frontal-subcortical circuit are thought to be a link between depression and executive dysfunction. Early detection of depressive symptoms and both pharmacological and non-pharmacological treatment would be helpful. In this review paper, the authors investigated 1) biological and neuroanatomical substrate for poststroke depression and executive dysfunction, 2) the relationship and common etiopathology for poststroke depression and executive dysfunction, and 3) pharmacological and non-pharmacological treatment for poststroke depression. The contents of the paper are as follows : the prevalence, clinical manifestation, and biological etiology for poststroke depression, neuroanatomical abnormalities as a common etiological factor for depression and executive dysfunction, pharmacotherapy and non-pharmacological approach.

Neural Substrates of Fear Based on Animal and Human Studies (공포의 신경 기저 회로 : 동물과 인간 대상 연구를 중심으로)

  • Baek, Kwangyeol;Jeong, Jaeseung;Park, Min-Sun;Chae, Jeong-Ho
    • Korean Journal of Biological Psychiatry
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    • v.15 no.4
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    • pp.254-264
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    • 2008
  • Objectives : The neural substrate of fear is thought to be highly conserved among species including human. The purpose of this review was to address the neural substrates of fear based on recent findings obtained from animal and human studies. Methods : Recent studies on brain regions related to fear, particularly fear conditioning in rodents and humans, were extensively reviewed. Results : This paper suggests high consistency in anatomical structure and physiological mechanisms for fear perception, response, learning and modulation in animals and humans. Conclusions : Fear is manifested and modulated by well conserved neural circuits among species interconnected with the amygdala, such as the hippocampus and the ventromedial prefrontal cortex. Further research is required to incorporate findings from animal studies into a better understanding of neural circuitry of fear in human in a translational approach.

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Perfusion Impairment in Infantile Autism on Brain SPECT Using Tc-99m ECD : Comparison with MR Findings (유아 자폐증 환아에서의 Tc-99m ECD를 이용한 뇌 단일 광전자 방출 전산화 단층 촬영술상의 관류 저하: 자기 공명 영상과의 비교 분석)

  • Ryu, Young-Hoon;Lee, Jong-Doo;Yoon, Pyeong-Ho;Kim, Dong-Ik;Oh, Young-Taik;Lee, Sun-Ah;Lee, Ho-Bun;Shin, Yee-Jin;Lee, Byung-Hee
    • The Korean Journal of Nuclear Medicine
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    • v.31 no.3
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    • pp.320-329
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    • 1997
  • Neuroanatomic substrate of autism has been the subjects of continuing investigation. Because previous studies had not demonstrated consistent and specific neuroimaging findings in autism and most studies comprised adults and school-aged children, we performed a retrospective review in search of common functional and anatomical abnormalities with brain SPECT using Tc-99m ECD and correlative MRI The patient population was composed of 18 children aged 28 to 89 months(mean age : 55 months) who met the diagnostic criteria of autism as defined in the DSM-IV and CARS. Brain SPECT was performed after intravenous injection of 185-370MBq of Tc-99m ECD using brain dedicated annular crystal gamma camera. MRI was performed in all patients including T1, T2 axial and T1 sagittal sequences. SPECT data were visually assessed. Thirteen patients had abnormal SPECT scan revealing focal areas of decreased perfusion. Decreased perfusion of cerebellar vermis(12/18), cerebellar hemisphere(11/18), thalami(13/18), basal ganglia(4/18), posterior parietal(7/18), and temporal(4/18) area were noted on brain SPECT. Whereas, only 3 patients had abnormal MR findings which were subtle volume loss of parieto-occipital white matter in 3 and mild thinning of posterior body of corpus callosum in 2 and slightly decreased volume of cerebellar vermis in 1. Comparison of the numbers of abnormal findings revealed that regional cerebral blood flow (rCBF) abnormalities seen on SPECT were more numerous than anatomical abnormalities seen on MRI. In conclusion, extensive perfusion impairment involving cerebellum, thalami and parietal lobe were found in this study. SPECT may be more sensitive in reflecting pathophysiology of autism than MRI. However, further studies are mandatory to determine the significance of thalamic and parietal perfusion impairment in autism.

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Relationships of Physiologieal Activity and Anatomical Structure to the Wilting Phenomena in Rice Plant 1. Reappearance of the Wilting Phenomena concerning to Physiological Aspects and Environment (수도품종의 위고현상과 생리 및 형태해부학적 구조와의 관련성에 관한 연구)

  • ;Jong-Hoon Lee
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.25 no.1
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    • pp.1-7
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    • 1980
  • In 1976, a newly released rice variety, Yushin, was planted in 300,000 ha of the 533,000 ha of cultivated total hecterage with new rice varieties. High productivity and quality were achieved by farmers around country. However, the wilting phenomena of Yushin occured in some regions where were employed poor cultural management, and flowed sewage into the paddy field from industrial factories. This study was identified some factors for the wilting phenomena of Yushin rice variety in morphological and physiological aspects. The Yushin variety showed greater internode elongation on low part of the stems that close related to lodge at heavier nitrogen levels, excessive number of spikelets per unit leaf blade weight i.e. higher sink/source ratio, and greater consumption of respiratory substrate by increased respiration rate of rice plant as compared with those of Tongil rice variety. In physilogical aspects, the Yushin variety was significantly declined root development and root activities under heavy nitrogen conditions. Yushin rice variety was decreased $K_2$O/N ratio, carbohydrate content in stem of rice plant, and physiological root activities specially in low light intensity, 50% light interception plots. Therefore, above factors were mainly promoted the wilting phenomena of Yushin rice variety.

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