• Title/Summary/Keyword: 핵자기 공명

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Spectroscopic Characterization of Soil Humic Acid Fractions by Molecular Weight (토양에서 추출한 흄산의 분자량별 분류에 따른 분광학적 성질 비교)

  • Shin, Hyun Sang;Moon, Hichung;Yang, Han Beom;Yun, Sock Sung
    • Journal of the Korean Chemical Society
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    • v.39 no.1
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    • pp.66-70
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    • 1995
  • The soil humic acid was subdivided into four subfractions by molecular weight (F1: >100.000 dalton; F2: >100.000 dalton; F3: >10.000 dalton; F4: >2.000 dalton) using MP-dual hollow fiber ultrafiltration system. The characterization using IR, 1H and 13C NMR spectroscopy, showed similar spectroscopic features of HA, demonstrating that the bulk properties of HA subfractions are very similar to one another. IR spectral data showed a decrease in polysaccharide contents and increase in carboxylate functionality as molecular weight become smaller.functions. The structure of (NO) can be described by two interactions (N${\cdot}{\cdot}{\cdot}$N, N${\cdot}{\cdot}{\cdot}$O). One is the ONNO structure with an (N${\cdot}{\cdot}{\cdot}$N) interaction. In this structure, acyclic cis-ONNO with $C_{2v}$-symmetry, acyclic trans-ONNO with $C_{2h}$, and cyclic ONNO with trapezoidal structure ($C_{2v}$) are optimized at the MP2 level. The other structure is the ONON structure with an (N${\cdot}{\cdot}{\cdot}$O) interaction. In the structure, acyclic cis-ONON with Cs$^{-symmetry}$ and cyclic ONON of the rectangular ($C_{2h}$), square $(D_{2h})$, rhombic $(D_{2h})$, and parallelogramic $(D_{2h})$ geometries are also optimized. It is found that acyclic cis-ONNO $(^1A_1$) is the most stable structure and cyclic ONNO ($^3A_1$) is the least stable. Acyclic trans-ONNO ($^3A_1$) with an (N${\cdot}{\cdot}{\cdot}$N) interaction, acyclic trans-ONON and bicyclic ONON $(C_{2v})$ with (N${\cdot}{\cdot}{\cdot}$O) interaction, and acyclic cis- and trans-NOON with an (O${\cdot}{\cdot}{\cdot}$O) interaction can not be optimized at the MP2 level. Particularly, acyclic trans-ONNO with $C_{2h}$-symmetry can not be optimized at the CCSD(T) level. Meanwhile, acyclic NNOO ($^1A_1$, $C_s)$ and trianglic NNOO ($^1A_1$,$C_{2v})$ formed by the (O${\cdot}{\cdot}{\cdot}$N) interaction between $O_2$and $N_2$are optimized at the MP2 level. The binding energies and the relative energy gaps among the isomers are found to be relatively small./sec. Spiral CT scans during the arterial phase were obtained 35 seconds after the injection of contrast medium. CT findings of 78 lesions less than 4cm in diameter were correlated with angiographic findings. Results : The attenuation of lesions was high(n = 69), iso(n = 5), and low(n = 4) compared with liver parenchyma during the arterial phase of spiral CT. In lesions with high-, iso-, and low-attenuation during the arterial phase of spiral CT, hypervascularity on angiograms was found in 63 of 69(91.3%), three of five(60%), and three of four lesions(75%), respectively. Six lesions with high-attenuation on the arterial phase of spiral CT were not seen on angiography. Two iso-attenuated and one low-attenuated lesion were hypovascular on angiograms. Conclusion : The results of this study suggest that with some exceptions there was good correlation between the arterial phase of spiral CT and angiography.

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The Effect of Ginkgo Biloba Extract on Hypoxic Fraction of C3H Mouse Fibrosarcoma (Ginkgo Biloba Extract가 C3H 마우스 섬유육종의 저산소세포 분획에 미치는 영향)

  • Cho Chul Koo;Yi Chun Ja;Ha Sung Whan;Park Charn Il
    • Radiation Oncology Journal
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    • v.13 no.3
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    • pp.205-214
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    • 1995
  • Purpose : To investigate the effect of Ginkgo biloba extract (GBE) on hypoxic cell fraction and metabolic status in fibrosarcoma (FSa II) of C3H mouse. Materials and Methods : Fibrosarcoma (FSa II) 6 mm in diameter, growing in the right hindleg muscle of C3H mouse was used for estimation of hypoxic cell fraction using comparison of $TCD_{50}$. Radiation was given one hour after administration of GBE (100 mg/kg. i.p.) with or without priming dose of GBE (100 mg/kg, i.p.) given 24 hours earlier. Radiation was also given under air breathing condition or clamp hypoxia without GBE as controls. $^{31}p$ NMR spectroscopy was performed before and one hour after administration of GBE with or without priming dose of GBE. Results : $TCD_{50/120's}$ were 81.7 (77.7-86.0) Gy when irradiated under clamped hypoxia 69.6 (66.8-72.5) Gy under air breathing condition. 67.5 (64.1-71.1) Gy with a single dose of GBE (100 mg/kg) given one hour before irradiation, and 62.2 (59.1-65.5) Gy with two doses of GBE given at 25 hours and one hour before irradiation. The hypoxic cell fractions, estimated from $TCD_{50/120's}$, were $10.6{\%}$ under air breathing condition, $7.2{\%}$ after a single dose of GBE, and $2.7{\%}$ after two doses of GBE. The results of $^{31}P$ NMR spectroscopy were as follow. PCr/Pi ratio was $0.27{\pm}0.04$ and $0.40{\pm}0.04$ before and one hour after a single dose of GBE (p<0.05), respectively, without priming dose and $0.30{\pm}0.02$ and $0.71{\pm}0.04$, respectively, with priming dose (p<0.01). These findings indicate that the metabolic status is slightly improved after a single dose and markedly after repeated administrations. Conclusion : GBE decreases the hypoxic cell fraction and imprvoes the meta bolic status of tumor, probably by increasing the blood flow and delivery of oxygen and nutrients, resulting in increased radiosensitivity of tumor.

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Effect of Composition on Isotropic Chemical Shift of Na Silicate and Aluminosilicate Glasses Using Solid State NMR (고상 핵자기공명 분광분석을 이용한 비정질 Na 규산염 및 알루미노규산염 내 조성에 따른 등방성 화학적 차폐 변화 규명)

  • Park, Sun Young;Lee, Sung Keun
    • Journal of the Mineralogical Society of Korea
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    • v.32 no.1
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    • pp.41-49
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    • 2019
  • Probing the Na environments in Na silicate and aluminosilicate glasses is essential to the macroscopic properties of melts in the Earth. In particular, exploring the atomic structure of Na silicate and aluminosilicate glasses reveals Na-O distance, which plays an important role in transport properties of melts. Here we report the local environment around Na using $^{23}Na$ magic angle spinning (MAS) NMR. We also obtain $^{23}Na$ isotropic chemical shift (${\delta}_{iso}$) of Na silicate and aluminosilicate glasses with varying composition using Dmfit program. The Q mas 1/2 model simulates the experimental results with three simulated peaks while the CzSimple model simulates with one peak. The ${\delta}_{iso}$ decreases with increasing $SiO_2$ content in Na silicate and aluminosilicate glasses. The ${\delta}_{iso}$ increases with increasing $Na_2O$ content in Na-Ca silicate and Na aluminosilicate glasses when the $SiO_2$ content is fixed. Considering the ${\delta}_{iso}$ of Na aluminosilicate glasses available in the previous studies, together with the current simulation results, we confirm that the ${\delta}_{iso}$ has positive correlation with Al / (Al + Si). Those experimental results were reproduced better using Q mas 1/2 model. The disorder of Na in Na silicate and aluminosilicate glasses can be revealed through the simulation of 1D $^{23}Na$ MAS NMR spectra using Dmfit program in a short time.

Multiple Daily Fractionated RT for Malignant Glioma (악성 성상세포종과 다형성 교아종 치료에 있어서 다분할 방사선 치료와 단순분할 방사선치료에 대한 성적비교)

  • Yang Kang Mo;Chang Hye Sook;Ahn Seoung Do;Choi Eun Kyung
    • Radiation Oncology Journal
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    • v.12 no.2
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    • pp.151-158
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    • 1994
  • Since Jan. 1992, authors have conducted a pilot study to treat malignant glioma with multiple daily fractionated(MDF) radiation therapy and this paper presents the outcome compared MDF to conventional factionated(CF) radiation therapy Between Sep. 1989 and Jan. 1993, forty three patients with high grade glioma of brain except brain stem glioma were treated: nineteen patients were treated with CF radiation therapy and 24 patients were treated with MDF radiation therapy. In CF radiation therapy, total dose was 6300cGy/35fx in 7 weeks, which 5040cGy was delivered to the initial target volume and 1260cGy to reduced target volume. And in MDF radiation therapy, total dose was 6400cGy/40fx in 4 weeks, which 3200cGy was delivered to the initial target volume as 160cGy 2 times daily 6hr apart. All patients had histologically confirmed anaplastic astrocytoma(AA) of glioblastoma multiforme (GBM) with stereotactic biopsy or craniotomy for subtotal or gross tumor resection. The range of follow-up was 7 months to 4 years with a median follow-up of 9 months. The Median survival from surgery was 9 months for all patients. The median survival was 9 months and 10 months for MDF group and CF group and 10 months and 9.5 months for glioblastoma multiforme and anaplastic astrocytoma, respectively. In 36 patients with follow-up CT scan or MRI scan, disease status was evaluated according to treatment groups, Four patients(GBM:3, AA:1) of 21 patients in MDF group, were alive with no evidence of disease, while none of patient was alive with no evidence of disease in CF group. The progression of disease had occurred in 20 patients, 11 patients and 9 patients in MDF group and CF group, respectively All of these patients showed in-field progression of disease, Four of 11 patients($27\%$) in MDF group showed the new leasion outside of the treatment field, while 5 of 9 patients($56\%$) in CF group. In our study the prognosis was not influenced by age, KPS, grade, extent of surgery and different fractional scheduled radiation therapy. Authors concluded that MDF regimen was well tolerated and shortened the treatment period from 7 weeks to 4 weeks without compromising results. We believe that further follow-up is needed to assess the role of MDF.

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CLINICAL STUDY OF THE ABUSE IN PSYCHIATRICALLY HOSPITALIZED CHILDREN AND ADOLESCENTS (소아청소년 정신과병동 입원아동의 학대에 대한 임상 연구)

  • Lee, Soo-Kyung;Hong, Kang-E
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.10 no.2
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    • pp.145-157
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    • 1999
  • This study was performed by the children and adolescents who were abused or neglected physically, emotionally that were selected in child & adolescents psychiatric ward. We investigated the number of these case in admitted children & adolescents, and also observed characteristics of symptoms, developmental history, characteristics of abuse style, characteristics of abusers, family dynamics and psychopathology. We hypothesized that all kinds of abuse will influnced to emotional, behavioral problems, developmental courses on victims, interactive effects on family dynamics and psychopathology. That subjects were 22 persons of victims who be determined by clinical observation and clinical note. The results of the study were as follows:1) Demographic characteristics of victims:ratio of sex was 1:6.3(male:female), mean age was $11.1{\pm}2.5$. According to birth order, lst was 12(54.5%), 2nd was 5(23%), 3rd was 2(9%) and only child was 3(13.5%). 2) Characteristics of family:According to socioeconomic status, middle to high class was 3(13.5%), middle one was 9(41.% ), middle to low one was 9(41%), low one was 1(0.5%). according to number of family, under the 3 person was 3(13.5%), 4-5 was 17(77.5%), 6-7 was 2(9%). according to marital status of parents, divorce or seperation were 5(23%), remarriage 2(9%), severe marital discord was 19(86.5%). In father, antisocial behavior was 7(32%), alcohol dependence was 10(45.5%). In mother, alcohol abuse was 5(23%), depression was 17(77.3%), history of psychiatric management was 6(27%). 3) Characteristics of abuse:Physical abuse was 18(81.8%), physical and emotional abuse and neglect were 4(18.2%). according to onset of abuse, before 3 years was 15(54.5%), 3-6 years was 5(27.5%), schooler was 1(15%). Only father offender was 2(19%), only mother offender was 8(35.4%), both offender was 8(35.4%), accompaning with spouse abuse was 7(27%), and accompaning with other sibling abuse was 4(18.2%). 4) General characteristics and developmental history of victims:Unwanted baby was 12(54.5%), developmental delay before abuse was9(41%), comorbid developmental disorder was 15(68%). there were 6(27.5%) who didn‘t show definite sign of developmental delay before abuse. 5) Main diagnosis and comorbid diagnosis:According to main diagnosis, conduct disorder 6(27.3%), borderline child 5(23%), depression4(18%), attention deficit hyperactivity disorder(ADHD) 4(18%), pervasive developmental disorder not otherwise specified 2(9%), selective mutism 1(5%). According to comorbid diagnosis, ADHD, borderline intelligence, mental retardation, learning disorder, developmental language disorder, oppositional defiant disorder, chronic tic disorder, functional enuresis and encoporesis, anxiety disorder, dissociative disorder, personality disorder due to medical condition. 5) Course of treatment:A mean duration of admission was $2.4{\pm}1.5$ months. 11(15%) showed improvement of symtoms, however 11(50%) was not changed of symtoms.

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