• Title/Summary/Keyword: $T_2$ contrast

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A COMPARATIVE STUDY OF RADIOGRAPHIC LANDMARKS OF T.M.J. BY VARIOUS TECHNIQUES (악관절이 방사선상에 의한 비교 연구)

  • Lee Yoo Dong
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.4 no.1
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    • pp.31-37
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    • 1974
  • The author has studied roentgenographic images of temporomandibular articulation using various conventional roentgenographies. The roentgenographic images have obtained by application of the contrast media on the glenoid fossa and condylar head in a human dry skull. Comparing the various roentgenograms by Modified Transcranial projection, A-P T.M. articulation projection, Reverse Towne projection, Mayer projection and Bregma-Menton projection. The author has drawn following results. 1. The sharp radiogaphic details were obtained by all technics used except the Bregma-Menton projection, which seemed to be impractical to the study of T.M.J. because of to be shortened the image of condylar head. 2. The best image of the condyle-fossa relationship was appeared by Modified Transcranial projection and better image was acquired by Orbito-Ramus projection, but there were all inferior in Reverse Towne projection, Mayer projection and Bregma-Menton projection. 3. In all of the above techniques, the radiographic images of condylar head were clear and were appeared to be the convex type in Modified Transcranial projection, the angled type in Orbito-Ramus and Reverse Towne projection, the flat type in Mayer projection and the distorted angled type in Bregma-Menton projection. 4. The radiographic image of condylar head was shortened in Bregma-Menton projection only and was magnified somewhat in other projection.

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Superparamagnetic Gd- and Mn-substituted Magnetite Fluids Applied as MRI Contrast Agents

  • Kim, Jong-Hee;Lee, Chang-Hyun;Lee, Sang-Kuk
    • Bulletin of the Korean Chemical Society
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    • v.30 no.6
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    • pp.1305-1308
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    • 2009
  • The experimental particle samples included ($Mn_{0.1}Fe_{0.9}$)O-$Fe_2O_3$ and FeO-($Gd_{0.1}Fe_{0.9}$)$_2O_3$ with $Mn^{2+}\;and\;Gd^{3+}$ substitutions in inverse spinel $Fe_3O_4$. A lecithin surfactant was adsorbed onto the magnetic particles by ultrasonication. The samples prepared showed excellent dispersibility at the mean size of 13 nm; their saturation magnetization values were 63 emu/g for the bare and Mn-substituted magnetites, and 56 emu/g for the Gd-substituted magnetite. The crystal structure of the substituted magnetites was very similar to that of the bare magnetite, due to a small amount of 0.1 mole fraction substituted in synthesizing the magnetite. The magnetite fluids, according to T2-weighted MR images, effectively diminished the signal intensity in the liver and spleen of Sprague-Dawley rats.

Preparation and Characterization of Stretch Fabric : Shrinkage and Elasticity Properties (신축성사 개발 및 물성평가 : 수축률 및 신축성의 평가)

  • Kang, Ki-Hyuk;Kim, Young-Sung;Son, Young-A
    • Textile Coloration and Finishing
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    • v.22 no.2
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    • pp.173-179
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    • 2010
  • In this study, we determine the stretch and shrinkage properties of conjugated yarns. The shrinkage(%) and elasticity(%) were determined by applying twist conditions of 0, 350, 800, 1000, 1200, 1400, 1600, 2000 T/M (twisting per meter). It is found that the shrinkage(%) and elasticity(%) gradually decreased with increasing T/M. Especially the elasticity(%) dramatically decreased over 1400 T/M condition. In contrast, it is showed that the handle and drapery properties decreased below 1000 T/M, which indicates that the optimal T/M condition could be 1000~1400. The effect of shrinkage(%) and elasticity(%) with different steam setting temperatures (60, 70, 80 and $90^{\circ}C$) was also determined. The shrinkage(%) decreased with increasing setting temperature, while the elasticity not changed. In this context, the optimal steam setting temperature could be $80^{\circ}C$ because it is not easy to weave with the yarns which was set below $80^{\circ}C$. The elasticity(%) decreased with increasing the density of warp and weft. To produce soft handle, excellent drapery and good stretch fabrics, the warp density needs to be reached by 90% of the ideal warp density. In the case of NaOH treatments to the fabrics, the elasticity(%) increased with increasing weight reduction. Therefore, this study have demonstrated that the conjugated yarns with core yarn and the SDY CD(cation dyeable spindraw yarn) as an effect yarn would be appropriate to produce excellent mixture-yarn, which displays clean appearance, good handle and excellent elasticity, The optimized conditions are as follows; 1000~1200 twist per meter, $80^{\circ}C$ steam setting temperature, 90% of ideal warp density and relaxation condition treated with 5g/l NaOH concentration.

Solitary Fibrous Tumor of the Ischiorectal Fossa : CT and MRI Findings (좌골직장와에서 기원하는 고립섬유종양: CT, MR 영상소견의 증례 보고)

  • Kim, Ki-Hwan;Cha, Sang-Hoon;Yeom, Suk-Keu;Lee, Seung-Hwa;Chung, Hwan-Hoon
    • Investigative Magnetic Resonance Imaging
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    • v.15 no.1
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    • pp.72-76
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    • 2011
  • Solitary fibrous tumor (SFT) is a rare neoplasm, which is usually presented as a pleural based mass, but can also occur in unusual locations based on its mesenchymal origin. However, the radiologic features of SFT occurred in the ischiorectal fossa have been rarely reported. In this case, we describe the MRI findings in a case of a SFT involving the ischiorectal fossa of a 36-year-old man. The tumor appeared as homogeneous iso-signal intensity relative to the adjacent muscle on T1 weighted images, a mixed high signal intensity on the T2 weighted images, and heterogeneous enhancement following the administration of the contrast material.

Metamorphic Evolution of the Ogcheon Metamorphic Belt: Review of Recent Studies and Remaining Problems (중부 옥천변성대의 변성진화: 최근의 연구결과 논평 및 문제점)

  • 조문섭;김현철
    • The Journal of the Petrological Society of Korea
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    • v.11 no.3_4
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    • pp.121-137
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    • 2002
  • Metamorphic evolution of the Ogcheon metamorphic belt has been studied by many investigators for the past few decades. P-T conditions of the Ogcheon metamorphic belt were estimated as 4.2-9.4 kbar and $490-630^{\circ}C$, corresponding to the medium-pressure type. In addition, the clockwise P-T-t path suggests a crustal-thickening event in association with the formation of thrust nappes. However, some details on deformation and orogeny of the Ogcheon metamorphic belt have been ambiguous yet. Although the metamorphic age has been also equivocal, recent isotopic studies strongly suggest that the peak metamorphism in the Ogcheon metamorphic belt has occurred at ca. 300-280 Ma between Late Carboniferous and Early Permian. It is thus inferred that the Ogcheon metamorphic belt and the Taebaegsan basin have evolved as separate terranes and that both were sutured at ca. 250-220 Ma. These results are partly in contrast with those of previous workers and require a revised framework for tectonic evolution of the Ogcheon belt. In addition, it is likely that the Ogcheon belt is correlative with the Hida marginal belt and the Hida metamorphic belt.

An Electrocardiographic Study on Tetrodotoxin Intoxicated Rabbits (Tetrodotoxin 중독가토(中毒家兎)의 심전도학적(心電圖學的) 연구(硏究))

  • Park, Yong-Kuk;Shin, Hong-Kee;Kim, Kee-Soon
    • The Korean Journal of Physiology
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    • v.10 no.1
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    • pp.41-48
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    • 1976
  • Tetrodotoxin (TTX) is the purified active principle responsible for tetrodon (Puffer-fish) poisoning which has long been known in the Orient. The pharmacological actions of TTX have been rather extensively investigated. Two of the most prominent effects of intravenousely administered TTX are severe hypotension and respiratory paralysis resulting from its depressant actions on tissues. This depressant actions of TTX in turn result from the selective inhibition of sodium-carrying mechanism which is essential to generation of the action potential. TTX differs from local anesthetics in that it does not affect potassium conductance. Although the mechanism of the hypotensive action of TTX remains a subject of controversy, most investigator agree that TTX-induced hypotension is caused by alteration in the blood vessels rather than the heart. Not only the study on the effects of TTX on cardiac function is meager but the results of reported works are often contradictory. The present study was undertaken to investigate the effect of TTX on the electrocardiogram of the rabbit and to compare them with well known electrocardiographical characteristics found in digitalis and quinidine intoxicated animals. The results obtained from the present study are summarized as follows. 1. No changes were found in P-R interval and QRS duration after i.v. administration of $1.0\;{\mu}g/kg\;to\;1.5\;{\mu}g/kg$ TTX to the animals. It is obvious that there were no conduction disturbance between atria and ventricles as well as in the ventricular tissue. 2. In $1.0\;{\mu}g/kg$ TTX group, S-T interval and T-P segment were not changed whereas marked changes were observed in $1.5\;{\mu}g/kg$ TTX group. 3. The first and second degree A-V blocks appeared in the $2.0\;{\mu}g/kg$ TTX group. 4. TTX differs from digitalis and quinidine in that it does not cause S-T interval depression and T-wave inversion. In contrast with digitalis, TTX caused Q-T interval prolongation.

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Association of FOXP3 Single Nucleotide Polymorphisms With Clinical Outcomes After Allogenic Hematopoietic Stem Cell Transplantation

  • Nam, Minjeong;Shin, Sue;Park, Kyoung Un;Kim, Inho;Yoon, Sung-Soo;Kwon, Tack-Kyun;Song, Eun Young
    • Annals of Laboratory Medicine
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    • v.38 no.6
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    • pp.591-598
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    • 2018
  • Background: Forkhead box P3 (FOXP3) is an important marker of regulatory T cells. FOXP3 polymorphisms are associated with autoimmune diseases, cancers, and allograft outcomes. We examined whether single nucleotide polymorphisms (SNPs) at the FOXP3 locus are associated with clinical outcomes after allogenic hematopoietic stem cell transplantation (HSCT). Methods: Five FOXP3 SNPs (rs5902434, rs3761549, rs3761548, rs2232365, and rs2280883) were analyzed by PCR-sequencing of 172 DNA samples from allogenic HSCT patients. We examined the relationship between each SNP and the occurrence of graft-versus-host disease (GVHD), post-HSCT infection, relapse, and patient survival. Results: Patients with acute GVHD (grades II-IV) showed higher frequencies of the rs3761549 T/T genotype, rs5902434 ATT/ATT genotype, and rs2232365 G/G genotype than did patients without acute GVHD (P =0.017, odds ratio [OR]=5.3; P =0.031, OR=2.4; and P =0.023, OR=2.6, respectively). Multivariate analysis showed that the TT genotype of rs3761549 was an independent risk factor for occurrence of acute GVHD (P =0.032, hazard ratio=5.6). In contrast, the genotype frequencies of rs3761549 T/T, rs5902434 ATT/ATT, and rs2232365 G/G were lower in patients with post-HSCT infection than in patients without infection (P =0.026, P =0.046, and P =0.031, respectively). Conclusions: rs3761549, rs5902434, and rs2232365 are associated with an increased risk of acute GVHD and decreased risk of post-HSCT infection.

MRI Findings of Renal Myxoma: A Case Report and Literature Review (신장 점액종의 MRI 소견: 증례 보고와 문헌고찰)

  • Sung Hyun Yu;Young Sup Shim;So Hyun Park;Seung Joon Choi;Dong Hae Chung;Sang Jin Yoon
    • Journal of the Korean Society of Radiology
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    • v.83 no.1
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    • pp.162-167
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    • 2022
  • Renal myxomas are very rare benign tumors. To date, a few cases have been reported in English literature, mostly in pathology and urology journals. Thus, there are few reports on the radiological findings associated with renal myxomas. We report on the imaging findings in a case of renal myxoma in a 62-year-old male. MRI demonstrated a well-defined mass in the left renal sinus, with intermediate high signal intensity on T2-weighted images and low signal intensity on T1-weighted images. The tumor showed gradual enhancement on contrast-enhanced T1-weighted images.

Analysis of 16S-23S rRNA Intergenic Spacer Regions of Aeromonas veronii biogroup sobria and A. caviae (Aeromonas veronii biogroup sobria와 Aeromonas caviae의 16S-23S rRNA Intergenic Spacer Regions 분석)

  • 강동율;이훈구
    • Korean Journal of Microbiology
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    • v.36 no.3
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    • pp.173-180
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    • 2000
  • The intern1 spacer regions (ISR) between the 16s and 23s $1_RNA$ genes of Aeronzonus iwonii blogroupsobria and A. caviae were investigated by PCR fragment length typing and DNA sequencing. A. iwonii bv.sobria has a speciIic 16s-23s pattern of 2-4 fiagments ranging Goin 479-539 bp, with the exception of thespecies Aeron7onns cmiae, which has 3 fragments ranglog from 470-602 bp. In all of the.4 vei*onii bv. sobr,iaand A, caviae strains examined in this study, the 470-481bp Tragnent, designated TSR-1, invariably contained $tDNA^{uc(GAT)$ and $tDNA^{Ala(TGC)$ in contrast to ISR-2 (513-525 bp). ISR-3 (537-539 bp) and ISR-4 (568-602 bp)containing TEX>$tDNA^{Olu(ITC)$ A stretch of 20 nucleotides (178-197 bp) in the ISR-4 was conserved only wit11mA.caiiue, from which the A. caiiae specific primer, named prAC-F, was designed and used for PCR with aAcaviae coimnon reverse primer A PCR product of 450 bp was apparent alnong I , caiizne strains, but not ii1.4.ijeronii bv. sob~ia strains. The PCR product was oot detected t"-om strains belonging to A. hjili-o~~hila, Ebrio,aud the family Ef\ulcornertei,obncteriaceae. This study provides the first molecular tool for mdentifying the species 8.caviae.ing the species 8. caviae.

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MDM2 T309G has a Synergistic Effect with P21 ser31arg Single Nucleotide Polymorphisms on the Risk of Acute Myeloid Leukemia

  • Ebid, Gamal T.;Sedhom, Iman A.;El-Gammal, Mosaad M.;Moneer, Manar M.
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.9
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    • pp.4315-4320
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    • 2012
  • Background: The P53 tumor suppressor gene plays a pivotal role in maintaining cellular homeostasis by preventing the propagation of genome mutations. P53 in its transcriptionally active form is capable of activating distinct target genes that contribute to either apoptosis or growth arrest, like P21. However, the MDM2 gene is a major negative regulator of P53. Single nucleotide polymorphisms (SNP) in codon Arg72Pro of P53 results in impairment of the tumor suppressor activity of the gene. A similar effect is caused by a SNP in codon 31 of P21. In contrast, a SNP in position 309 of MDM2 results in increased expression due to substitution of thymine by guanine. All three polymorphisms have been associated with increased risk of tumorigenesis. Aim of the study: We aimed to study the prevalence of SNPs in the P53 pathway involving the three genes, P53, P21 and MDM2, among acute myeloid leukemia (AML) patients and to compare it to apparently normal healthy controls for assessment of impact on risk. Results: We found that the P21 ser31arg heterozygous polymorphism increases the risk of AML (P value=0.017, OR=2.946, 95% CI=1.216-7.134). Although the MDM2 309G allele was itself without affect, it showed a synergistic effect with P21 ser/arg polymorphism (P value=0.003, OR=6.807, 95% CI=1.909-24.629). However, the MDM2 309T allele abolish risk effect of the P21 polymorphic allele (P value=0.71). There is no significant association of P53 arg72pro polymorphism on the risk of AML. Conclusion: We suggest that SNPs in the P53 pathway, especially the P21 ser31arg polymorphism and combined polymorphisms especially the P21/MDM2 might be genetic susceptibility factors in the pathogenesis of AML.