• Title/Summary/Keyword: Signal Sequence

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Evaluation of Metabolic Abnormality in Brain Tumors by In Viuo $^1$H MR Spectroscopy at 3 Tesla (3T 양성자 자기공명분광에 의한 뇌종양의 대사물질 이상소견)

  • Choe, Bo-Young;Jeun, Sin-Soo;Kim, Bum-Soo;Lee, Jae-Mun;Chung, Sung-Taek;Ahn, Chang-Beom;Oh, Chang-Hyun;Kim, Sun I.;Lee, Hyoung-Koo
    • Progress in Medical Physics
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    • v.13 no.3
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    • pp.120-128
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    • 2002
  • To investigate differences between the metabolic ratios of normal controls and brain tumors such as astrocytomas and glioblastoma multiforme (GM) by proton MR spectroscopy (MRS) at 37 high field system. Using 3T MRI/MRS system, localized water-suppressed single-voxel technique in patients with brain tumors was employed to evaluate spectra with peaks of N-acetyl aspartate (NAA), choline-containing compounds (Cho), creatine/phosphocreatine (Cr) and lactate. On the basis of Cr, these peak areas were quantificated as a relative ratio. The variation of metabolites measurements of the designated region in 10 normal volunteers was less than 10%. Normal ranges of NAA/Cr and Cho/Cr ratios were 1.67$\pm$018 and 1.16$\pm$0.15, respectively. NAA/Cr ratio of all tumor tissues was significantly lower than that of the normal tissues (P=0.005). Cho/Cr ratio of glioblastoma multiforme was significantly higher than that of astrocytomas (P=0.001). Lactate was observed in all tumor cases. The present study demonstrated that the neuronal degradation or loss was observed in all tumor tissues. Higher grade of brain tumors was correlated with higher Cho/Cr ratio, indicating a significant dependence of Cho levels on malignancy of gliomas. This results suggest that clinical proton MR spectroscopy could be useful to predict tumor malignancy.

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A problem of authenticity in the chapter 'Confucius became aged, and liked "The Book of Changes"' of yao 要, "essentials," seen throughout 『帛書周易』 the Mawangdui Boshu Zhouyi Manuscript. -in relation to Confucius and 『易』"The Changes"- (『백서주역(帛書周易)』 「요(要)」의 '부자노이호역(夫子老而好易)'장의 진위(眞僞) 문제 -공자와 『역』의 관계를 중심으로-)

  • Kim, Sang-sup
    • Journal of Korean Philosophical Society
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    • v.129
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    • pp.1-22
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    • 2014
  • Columns 12-18 record a conversation between an aged Confucius and his disciple Zi Gong concerning the Changes and especially the role of divination in its use. The last section, from the bottom of column 24, concerns the hexagrams Sun損, "Decrease," and Yi益, "Increase," which Confucius is here made to regard as the culmination of wisdom in the Zhouyi. The conversation between Confucius and Zi Gong, and especially Zi Gong's apparent misunderstanding of Confucius's interest in the text, has already attracted considerable scholarly interest. Zi Gong criticizes Confucius for changing his teaching about the importance of the Zhouyi and for performing divinations. Confucius responds that while he does indeed perform divinations. there is a major difference between his use of the text and that of others: he regards the I Ching as a repository of an ancient wisdom. This would seem to signal recognition of a dramatic change in the function and status of the text. Zi Gong said: "Does the Master also believe in milfoil divination?" The Master said: "I am right in only seventy out of one hundred prognostications. Even with the prognostications of Liangshan of Zhou one necessarily follows it most of the time and no more." The Master said: "As for the Changes, I do indeed put its prayers and divinations last, only observing its virtue and property. Intuiting the commendations to reach the number, and understanding the number to reach virtue, is to have humaneness and to put it into motion properly. If the commendation do not lead to the number, then merely acts as a magician; if the number does not lead to virtue, then one merely acts as a scribe. The divinations of scribes and magicians tend toward it but are not yet there; delight in it but are not correct. Perhaps it will be because of the Changes that sires of later generations will doubt me. I seek its virtue and nothing more. I am on the same road as the scribes and magicians but end up differently. The conduct of the gentleman's virtue is to seek blessings; that is why he sacrifices, but little; the righteousness of his humaneness is to seek auspiciousness; that is why he divines, but rarely. Do not the divinations of priest and magicians come last!" Although Confucius says two ways of the symbolic numbers and virtue-property, he emphasizes his way of virtue and property more important. In fact he who wrote in Yao 要, "essentials," Confucius's saying describes his own viewpoints of the Changes throughout the conversations between Confucius and his disciple Zi Gong, and is only to borrow the name of Confucius. Furthermore, quoting the original text in Yao 要, "essentials," in sequence, also comparing the materials of "the Analects of Confucius論語," with "the Shih chi史記," this thesis will be centered to a great extent on the relative similarity and differences between the Mawangdui Boshu Zhouyi Manuscript and the received text, and discussed the authencity of Yao 要, "essentials," of the contents shown in the chapter of 'Confucius became aged, and liked "The Book of Changes."' the relation of Confucius and the Changes will be clarified naturally through this progress.

The Comparative Imaging Study on Mn-phthalocyanine and Mangafodipir trisodium in Experimental VX2 Animal Model (실험적으로 유발시킨 VX2 동물모델에서의 Mn-phthalocyanine과 Mangafodipir trisodium의 비교영상)

  • Park Hyun-Jeong;Ko Sung-Min;Kim Yong-Sun;Chang Yongmin
    • Investigative Magnetic Resonance Imaging
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    • v.8 no.1
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    • pp.32-41
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    • 2004
  • Purpose : To measure the NMR relaxation properties of MnPC, to observe the characteristics of liver enhancement patterns on MR images in experimentally implanted rabbit VX2 tumor model, and to estimate the possibility of tissue specific contrast agent for MnPC in comparison with the hepatobiliary agent. Materials and Methods : Phthalocyanine (PC) was chelated with paramagnetic ions, manganese (Mn). 2.01 g (5.2 mmol) of phthalocyanine was mixed with 0.37 g (1.4 nlmol) of Mn chloride at $310^{\circ}C$ for 36 hours and then purified by chromatography ($CHCl_3:\;CH_3OH=98:2$, volume ratio) to obtain 1.04 g $(46\%)$ of MnPC (molecular weight = 2000 daltons). The T1/T2 relaxivity (R1/R2) for MnPC were determined at a 1.5 T (64 MHz) MR spectrometer. VX2 tumor model was experimentally implanted in the liver parenchyma of rabbits. All MR studies were performed on 1.5 T. The human extremity radio frequency coil of a bird cage type was employed. MR images were acquired at 17 to 24 days after VX2 carcinoma implantation.4 mmol/kg MnPC and 0.01 mmol/kg Mn-DPDP were injected via the ear vein of rabbits. T1-weighted images were obtained with spin-echo (TR/TE=516/14 msec) and fast multiplanar spoiled gradient recalled (TR/TE : 80/4 msec, $60^{\circ}$ flip angle) pulse sequence. Fast spin-echo (TR/TE=1200/85 msec) was used to obtain the T2-weighted images. Results : The value of T1/T2 relaxivity (R1/R2) of MnPC was $7.28\;mM^{-1}S^{-1}$ and $55.56\;mM^{-1}S^{-1}$ respectively at 1.5 T (64 MHz). Because the T2 relaxivity of MnPC that bonded strongly, covalently manganese with phthalocyanine was very high, the signal intensity of liver parenchyma was decreased on postcontrast T2-weighted images and we could easily distinguish the VX2 carcinoma within the liver parenchyma. When MnPC was administrated intravenously, the tumor margin delineation was more remarkable than Mn-DPDP-enhanced images. The enhancement of liver parenchyma with MnPC persisted at relatively high levels over at least one hour after injection of the contrast agents. Conclusion : The hepatic uptake and biliary excretion of MnPC, which are similar to Mn-DPDP, suggest that this agent is a new liver-specific agent. Also, MnPC seems to be used as a dual contrast agent (T1 and T2) with high T2 relaxivity. However, it is warranted that MnPC needs further investigation as a potential contrast agent for MR imaging of the liver. That is, further characterizations of MnPC are needed in vivo and in vitro before clinical trials. The diagnostic potential of MnPC will also have to be examined more in the animal models of additional types.

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