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Urinary nuclear magnetic resonance spectroscopy of a Bangladeshi cohort with hepatitis-B hepatocellular carcinoma: A biomarker corroboration study 被引量:6
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作者 I Jane Cox Abil E Aliev +7 位作者 Mary ME Crossey Mahvish Dawood Mamun Al-Mahtab Sheikh M Akbar Salimur Rahman Antonio Riva Roger Williams Simon D Taylor-Robinson 《World Journal of Gastroenterology》 SCIE CAS 2016年第16期4191-4200,共10页
AIM: To establish if a distinct urinary metabolic profile could be identified in Bangladeshi hepatitis-B hepatocellular carcinoma (HCC) patients compared to cirrhosis patients and controls.METHODS: Urine samples from ... AIM: To establish if a distinct urinary metabolic profile could be identified in Bangladeshi hepatitis-B hepatocellular carcinoma (HCC) patients compared to cirrhosis patients and controls.METHODS: Urine samples from 42 Bangladeshi patients with HCC (39 patients with hepatitis-B HCC), 47 with cirrhosis on a background of hepatitis B, 46 with chronic hepatitis B, and seven ethnically-matched healthy controls were analyzed using nuclear magnetic resonance (NMR) spectroscopy. A full dietary and medication history was recorded for each subject. The urinary NMR data were analyzed using principal component analysis (PCA) and orthogonal partial least squared discriminant analysis (OPLS-DA) techniques. Differences in relative signal levels of the most discriminatory metabolites identified by PCA and OPLS-DA were compared between subject groups using an independent samples Kruskal-Wallis one-way analysis of variance (ANOVA) test with all pairwise multiple comparisons. Within the patient subgroups, the Mann-Whitney U test was used to compare metabolite levels depending on hepatitis B e-antigen (HBeAg) status and treatment with anti-viral therapy. A Benjamini-Hochberg adjustment was applied to acquire the level of significance for multiple testing, with a declared level of statistical significance of P &#x0003c; 0.05.RESULTS: There were significant differences in age (P &#x0003c; 0.001), weight (P &#x0003c; 0.001), and body mass index (P &#x0003c; 0.001) across the four clinical subgroups. Serum alanine aminotransferase (ALT) was significantly higher in the HCC group compared to controls (P &#x0003c; 0.001); serum &#x003b1;-fetoprotein was generally markedly elevated in HCC compared to controls; and serum creatinine levels were significantly reduced in the HCC group compared to the cirrhosis group (P = 0.004). A three-factor PCA scores plot showed clustering of the urinary NMR spectra from the four subgroups. Metabolites that contributed to the discrimination between the subgroups included acetate, creatine, creatinine, dimethyamine (DMA), formate, glycine, hippurate, and trimethylamine-N-oxide (TMAO). A comparison of relative metabolite levels confirmed that carnitine was significantly increased in HCC; and creatinine, hippurate, and TMAO were significantly reduced in HCC compared to the other subgroups. HBeAg negative patients showed a significant increase in creatinine (P = 0.001) compared to HBeAg positive patients in the chronic hepatitis B subgroup, whilst HBeAg negative patients showed a significant decrease in DMA (P = 0.004) in the cirrhosis subgroup compared to HBeAg positive patients. There were no differences in metabolite levels in HCC patients who did or did not receive antiviral treatment.CONCLUSION: Urinary NMR changes in Bangladeshi HCC were identified, corroborating previous findings from Egypt and West Africa. These findings could form the basis for the development of a cost-effective HCC dipstick screening test. 展开更多
关键词 Urinary metabolic profiling Hepatocellular carcinoma nuclear magnetic resonance spectroscopy Hepatitis B Bangladesh
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Using Nuclear Magnetic Resonance and MS/MS Spectroscopy for the Identification of Brodimoprim Metabolites in Rat Urine 被引量:1
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作者 Chun YANG Wen Yi HE +4 位作者 Li Jun LI Rui Ming XU Shou Ren ZHANG Zeper ABLIZ Yi Kang SI 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第6期513-516,共4页
Eight metabolites of brodimoprim (BDP) in rat urine were detected by NMR and ESIMS/MS. They were demethyl-BDP glucuronide, demethyl-BDP sulfurate, demethyl-BDP glucuronide sulfurate, alpha -hydroxyl-BDP, alpha -hydrox... Eight metabolites of brodimoprim (BDP) in rat urine were detected by NMR and ESIMS/MS. They were demethyl-BDP glucuronide, demethyl-BDP sulfurate, demethyl-BDP glucuronide sulfurate, alpha -hydroxyl-BDP, alpha -hydroxyl-BDP glucuronide, BDP sulfurate, N-oxide-BDP sulfurate, and alpha -hydroxyl-N-oxide-BDP sulfurate. All the sulfurates are reported for the first time. 展开更多
关键词 nuclear magnetic resonance spectroscopy MS/MS spectroscopy METABOLITES BRODIMOpRIM
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Nuclear magnetic resonance spectroscopy is highly sensitive for lipid-soluble metabolites 被引量:1
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作者 Haiyang Dai Bikai Hong +4 位作者 Zhifeng Xu Lian Ma Yaowen Chen Yeyu Xiao Renhua Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第22期2103-2110,共8页
Although the water-soluble metabolite profile of human mesenchymal stem cells is known, the lipid profile still needs further investigation. In this study, methanol-chloroform was used to extract lipid-soluble metabol... Although the water-soluble metabolite profile of human mesenchymal stem cells is known, the lipid profile still needs further investigation. In this study, methanol-chloroform was used to extract lipid-soluble metabolites and perchloric acid was used to extract water-soluble metabolites. Fur- thermore, a dual phase extraction method using methanol-chloroform and water was used to obtain both water and lipid fractions simultaneously. All metabolite extractions were analyzed on a 9.4T high-resolution nuclear magnetic resonance spectrometer. Metabolite resonance peaks were as- signed in the acquired spectra according to the chemical shift, and the extraction efficiency of dif- ferent methods was compared. Results showed that in the spectra of water-soluble extracts, major metabolites comprised low molecular weight metabolites, including lactate, acetic acid, fatty acids, threonine, glutamic acid, creatine, choline and its derivatives, while in the spectra of lipid-soluble extracts, most metabolites were assigned to fatty acids. Among the different extraction procedures, perchloric acid was more efficient in extracting water-soluble metabolites and methanol-chloroform was efficient in extracting organic components compared with the dual phase extraction method. Nuclear magnetic resonance spectroscopy showed that as low as 0.7 mg organic yield was enough to obtain clear resonance peaks, while about 6.0 mg water-soluble yield was needed to obtain rela- tively favorable spectral lines. These results show that the efficiency of extracting water and lipid fractions is higher using perchloric acid and methanol-chloroform compared with dual phase ex- traction and that nuclear magnetic resonance spectroscopy is highly sensitive for analyzing lipid-soluble extracts. 展开更多
关键词 neural regeneration nuclear magnetic resonance spectroscopy mesenchymal stem cells metabo-lite profiles extraction method optimization WATER-SOLUBLE lipid-soluble perchloric acid metha-nol-chloroform grants-supported paper NEUROREGENERATION
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Analyzing pH value, energy and phospholipid metabolism of various cerebral tumors and normal brain tissue with ^(31)P magnetic resonance spectroscopy
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作者 Wei Tan Guangyao Wu Junmo Sun 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第3期248-252,共5页
BACKGROUND: ^31p magnetic resonance spectroscopy (^31p MRS) can be used to non-injuredly and dynamicly detect vadous metabolites including phosphorus in organis and reflect changes of phospholipid metabolism and en... BACKGROUND: ^31p magnetic resonance spectroscopy (^31p MRS) can be used to non-injuredly and dynamicly detect vadous metabolites including phosphorus in organis and reflect changes of phospholipid metabolism and energy metabolism in tissue and pH value in cells. OBJECTIVE: To observe changes of pH value, phospholipid metabolism and energy metabolism of various cerebral tumors and normal brain tissue with sip MRS. DESIGN: Semi-quantitative contrast observation PARTICIPANTS : A total of 44 patients with cerebral tumor diagnosed with surgery operation were selected from the Department of Magnetic Resonance, Central South Hospital, Wuhan University from September 2004 to June 2006. All the subjects had complete sip MRS data before steroid and operation. Among them, 16 patients had glioma of grade Ⅱ-Ⅲ, 12 spongioblastoma and 16 meningioma. The mean age was (45±6) years. Another 36 subjects without focus on cerebral MRI were regarded as normal group, including 19 males and 18 females, and the mean age was (41±4) years. Included subjects were consent. METHODS: Eclipse1.5T MRS (Philips Company) was used to collect wave spectrum; jMRUI(1.3) was used to analyze expenmental data and calculate pH value in voxel and ratios of phosphocreatine (PCr)/inorganic phosphate (Pi), PCr/phosphodiesterase (PDE) and phosphomonoesterase (PME)/β-adenosine triphosphate (β-ATP) of vadous metabolites. ^31p MRS results were compared with t test between tumor patients and normal subjects. MAIN OUTCOME MEASURES: Changes of phospholipid metabolism (PME./PDE), energy metabolism (PCr/ATP) and pH value of various cerebral tumors and normal brain tissues. RESULTS : A total of 44 cases with cerebral tumor and 36 normal subjects were involved in the final analysis. pH value and semi-quantitative measurements of normal brain tissues and various cerebral tumors: ① pH value at top occipital region and temple occipital region of normal brain tissue was 7.04 ±0.02; PCr/β-ATP was 1.51 ±0.03; PCr/Pi was 2.85±0.20; PDE/β-ATP was 2.70±0.40; PME/β-ATP was 1.01 ±0.03. Giioma of grade Ⅱ - Ⅲ : Tumor tissue was alkalized. The pH value was 7.09±0.01, which was higher than that in normal group (t=-1.823, P 〈 0.05); PCr/β-ATP, PME/β-ATP and PCr/ Pi were 1.50±0.04, 1.04±0.07 and 2.49±0.21, respectively, which was close to that in normal group (P 〉 0.05); PDE/β-ATP was 1.73±0.20, which was lower than that in normal group (t=-2.168, P 〈 0.05). ③ Spongioblastoma: Tumor tissue was alkalized. The pH value was 7.12±0.02, which was higher than that in normal group (t=-2.170, P 〈 0.05); PCr/β-ATP and PCr/Pi were 1.48±0.05 and 2.39±0.23, respectively, which was lower than that in normal group, but the difference was not significant (P 〉 0.05); PDE/β-ATP was 1.61±0.25, which was lower than that in normal group (t=-3.582, P 〈 0.01); PME/β-ATP was 1.64±0.05, which was higher than that in normal group (t=-3.930, P 〈 0.01). ④ Meningioma: Tumor tissue was alkalized. The pH value was 7.16±0.03, which was higher than that in normal group (t=-2.978, P 〈 0.01); PCr/β-ATP, PCr/Pi and PDE/β-ATP were 0.46±0.04, 1.08±0.16 and 0.82±0.10, respectively, which was lower than that in normal group (t=-3.132, 3.983, 3.985, P 〉 0.01); PME/β-ATP was 2.05±0.03, which was higher than that in normal group (t=-3.007, P〈 0.01). CONCLUSION: ^31p MRS can provide informations about pH value of cerebral tumor, phospholipid metabolism and energy metabolism. Changes of pH value, PCr, PME and PDE can reflect metabolic characteristics of various cerebral tumors. 展开更多
关键词 p magnetic resonance spectroscopy Analyzing pH value pDE pH
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31P Nuclear Magnetic Resonance of Charge-Density-Wave Transition in a Single Crystal of RuP
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作者 范国志 陈荣艳 +1 位作者 王楠林 雒建林 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期147-150,共4页
We perform 31p nuclear magnetic resonance (NMR) measurements on a single crystal of RuP. The anomalies in resistivity at about TA = 270 K and TB = 330 K indicate that two phase transitions occur. The line shape of a... We perform 31p nuclear magnetic resonance (NMR) measurements on a single crystal of RuP. The anomalies in resistivity at about TA = 270 K and TB = 330 K indicate that two phase transitions occur. The line shape of alp NMR spectra in different temperature ranges is attributed to the charge density distribution. The Knight shift and spin-lattice relaxation rate 1/T1T are measured from 1OK to 30OK. At about TA = 270K, they both decrease abruptly with the temperature reduction, which reveals the gap-opening behavior. Well below TA, they act like the case of normal metal. Charge-density-wave phase transition is proposed to interpret the transition occurring at about TA. 展开更多
关键词 Ru p nuclear magnetic resonance of Charge-Density-Wave Transition in a Single Crystal of Rup CDW DOS
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Conformational Analysis of γ-Butyrolactones by Nuclear Magnetic Resonance Spectroscopy
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作者 Fu An KANG and Cheng Lie YIN (Department of Chemistry Beijing Normal University , Beijing 100875) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第10期885-888,共4页
A series of trans-4, 5-disubstituted -γ-butyrolactones are found to assume two different envelope conformations by means of nuclear magnetic resonance spectroscopy.
关键词 Conformational Analysis of Butyrolactones by nuclear magnetic resonance spectroscopy
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ANALYSIS OF HUMAN PLACENTA BY ^(31)P NUCLEAR MAGNETIC RESONANCE AND THIN-LAYER CHROMATOGRAPHY SCANNING COMBINED WITH THE CORRECTIVE METHOD OF ABSORBANCE PROPORTIONAL COEFFICIENT
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作者 Rong GUO Jian wei CHEN Yi Min XU AiHua ZHANG Nanjing College of Traditional Chinese Medicine,Nanjing 210029 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第12期1081-1084,共4页
Five phospholipids in human placenta were determined by phosphorus 31 nuclear magnetic resonance(^(31)P NMR)spectroscopy and thin-layer chromatography(TLC) scanning combined with the corrective method of absorbance pr... Five phospholipids in human placenta were determined by phosphorus 31 nuclear magnetic resonance(^(31)P NMR)spectroscopy and thin-layer chromatography(TLC) scanning combined with the corrective method of absorbance proportional coefficient. The NMR spectrometer used this investigation was a Bruker AM-500 spectrometer operating at 202.4 MHz for ^(31)P chemical shifts are relative to 85% phosphoric acid. TIC was carried out by silica gel H plate developed in chloroform-methanol-glacial acetic acid-ethanol-water(25:4:6:2:0.5),with Vaskovsky reagent as colour -developing agent of phospholipids. 展开更多
关键词 p nuclear magnetic resonance AND THIN-LAYER CHROMATOGRApHY SCANNING COMBINED WITH THE CORRECTIVE METHOD OF ABSORBANCE pROpORTIONAL COEFFICIENT ANALYSIS OF HUMAN pLACENTA BY LpC TLC
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Crystallochemical Characterizations, Raman Spectroscopy and Studies Nuclear Magnetic Resonance (NMR) of Cu<sub>2</sub>Zn(Sn, Si)S<sub>4 </sub>Compounds for Photovoltaic Applications
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作者 Mohamed Hamdi Messaoud Benamira 《Journal of Materials Science and Chemical Engineering》 2022年第1期24-40,共17页
In this study, Si-doped Cu<sub>2</sub>ZnSnS<sub>4</sub> compounds (Cu<sub>2</sub>ZnSn<sub>1-x</sub>Si<sub>x</sub>S<sub>4</sub>, 0 ≤ x ≤ 1) were... In this study, Si-doped Cu<sub>2</sub>ZnSnS<sub>4</sub> compounds (Cu<sub>2</sub>ZnSn<sub>1-x</sub>Si<sub>x</sub>S<sub>4</sub>, 0 ≤ x ≤ 1) were prepared by solid state reaction method for use of materials for photovoltaic cells. The structural and spectroscopic properties of the as-prepared compounds were studied by X-ray diffraction (XRD), <sup>119</sup>Sn, <sup>29</sup>Si and <sup>65</sup>Cu Magic Angle Spinning nuclear magnetic resonance (MAS NMR) and Raman spectroscopy. The Si-substitution in the Sn-site induces three different types of XRD patterns which depend largely on the Si content in the compound. For 0 ≤ x ≤ 0.5, XRD analysis reveals the presence of a pure tetragonal phase of solid solution with I-42m as a space group. Mixed tetragonal and orthorhombic phases were observed for 0.5 < x < 0.8, followed by a pure orthorhombic structure with a space group Pmn2<sub>1</sub> at high content of Si (x ≥ 0.8). <sup>119</sup>Sn MAS NMR spectra show the presence of Sn/Si disorder as a function of the Si content. The <sup>65</sup>Cu MAS NMR spectra of the quadratic solid solution confirm the presence of the two copper sites (Cu-2a and Cu-2c) at 780 ppm while in the case of the orthorhombic solid solution samples, a very broad band is observed. The optical properties were investigated of all compounds by UV-Vis diffuse reflectance and the obtained optical band gap values (1.31 to 2.43 eV) confirm a semiconductor character. 展开更多
关键词 photovoltaic Cells Cu2ZnSnS4 nuclear magnetic resonance Raman spectroscopy
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7.0T nuclear magnetic resonance evaluation of the amyloid beta(1–40) animal model of Alzheimer's disease: comparison of cytology verification 被引量:6
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作者 Lei Zhang Shuai Dong +1 位作者 Guixiang Zhao Yu Ma 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第4期430-435,共6页
3.0T magnetic resonance spectroscopic imaging brain function in Alzheimer's disease. However, is a commonly used method in the research ot the role of 7.0T high-field magnetic resonance spectroscopic imaging in brain... 3.0T magnetic resonance spectroscopic imaging brain function in Alzheimer's disease. However, is a commonly used method in the research ot the role of 7.0T high-field magnetic resonance spectroscopic imaging in brain function of Alzheimer's disease remains unclear. In this study, 7.0T magnetic resonance spectroscopy showed that in the hippocampus of Alzheimer's disease rats, the N-acetylaspartate wave crest was reduced, and the creatine and choline wave crest was elevated. This finding was further supported by hematoxylin-eosin staining, which showed a loss of hippocampal neurons and more glial cells. Moreover, electron microscopy showed neuronal shrinkage and mitochondrial rupture, and scanning electron microscopy revealed small size hippocampal synaptic vesicles, incomplete synaptic structure, and reduced number. Overall, the results revealed that 7.0T high-field nuclear magnetic resonance spectroscopy detected the lesions and functional changes in hippocampal neurons of Alzheimer's disease rats in vivo, allowing the possibility for assessing the success rate and grading of the amyloid beta (1-40) animal model of Alzheimer's disease. 展开更多
关键词 nerve regeneration Alzheimer's disease AΒ1-40 high-field functional magnetic resonance nuclear magnetic resonance spectroscopy NEUROpATHOLOGY N-ACETYLASpARTATE CREATINE CHOLINE hippocampus NSFC grant neural regeneration
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Proton nuclear magnetic resonance-based metabonomic models for non-invasive diagnosis of liver fibrosis in chronic hepatitis C:Optimizing the classification of intermediate fibrosis 被引量:3
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作者 Andrea Dória Batista Carlos Jonnatan Pimentel Barros +7 位作者 Tássia Brena Barroso Carneiro Costa Michele Maria Goncalves de Godoy Ronaldo Dionísio Silva Joelma Carvalho Santos Mariana Montenegro de Melo Lira Norma ThoméJucá Edmundo Pessoa de Almeida Lopes Ricardo Oliveira Silva 《World Journal of Hepatology》 CAS 2018年第1期105-115,共11页
AIM To develop metabonomic models(MMs), using 1 H nuclear magnetic resonance(NMR) spectra of serum, to predict significant liver fibrosis(SF: Metavir ≥ F2), advanced liver fibrosis(AF: METAVIR ≥ F3) and cirrhosis(C:... AIM To develop metabonomic models(MMs), using 1 H nuclear magnetic resonance(NMR) spectra of serum, to predict significant liver fibrosis(SF: Metavir ≥ F2), advanced liver fibrosis(AF: METAVIR ≥ F3) and cirrhosis(C: METAVIR = F4 or clinical cirrhosis) in chronic hepatitis C(CHC) patients. Additionally, to compare the accuracy of the MMs with the aspartate aminotransferase to platelet ratio index(APRI) and fibrosis index based on four factors(FIB-4). METHODS Sixty-nine patients who had undergone biopsy in the previous 12 mo or had clinical cirrhosis were included. The presence of any other liver disease was a criterion for exclusion. The MMs, constructed using partial least squares discriminant analysis and linear discriminant analysis formalisms, were tested by cross-validation, considering SF, AF and C. RESULTS Results showed that forty-two patients(61%) presented SF, 28(40%) AF and 18(26%) C. The MMs showed sensitivity and specificity of 97.6% and 92.6% to predict SF; 96.4% and 95.1% to predict AF; and 100% and 98.0% to predict C. Besides that, the MMs correctly classified all 27(39.7%) and 25(38.8%) patients with intermediate values of APRI and FIB-4, respectively. CONCLUSION The metabonomic strategy performed excellently in predicting significant and advanced liver fibrosis in CHC patients, including those in the gray zone of APRI and FIB-4, which may contribute to reducing the need for these patients to undergo liver biopsy. 展开更多
关键词 Metabolomics nuclear magnetic resonance spectroscopy Chronic HEpATITIS C Liver FIBROSIS Surrogate MARKERS
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Nuclear magnetic resonance based metabolomics and liverdiseases:Recent advances and future clinical applications 被引量:7
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作者 Roland Amathieu Mohamed Nawfal Triba +4 位作者 Corentine Goossens Nadia Bouchemal Pierre Nahon Philippe Savarin Laurence Le Moyec 《World Journal of Gastroenterology》 SCIE CAS 2016年第1期417-426,共10页
Metabolomics is defined as the quantitative measurement of the dynamic multiparametric metabolic response of living systems to pathophysiological stimuli or genetic modification.It is an"omics"technique that... Metabolomics is defined as the quantitative measurement of the dynamic multiparametric metabolic response of living systems to pathophysiological stimuli or genetic modification.It is an"omics"technique that is situated downstream of genomics,transcriptomics and proteomics.Metabolomics is recognized as a promising technique in the field of systems biology for the evaluation of global metabolic changes.During the last decade,metabolomics approaches have become widely used in the study of liver diseases for the detection of early biomarkers and altered metabolic pathways.It is a powerful technique to improve our pathophysiological knowledge of various liver diseases.It can be a useful tool to help clinicians in the diagnostic process especially to distinguish malignant and non-malignant liver disease as well as to determine the etiology or severity of the liver disease.It can also assess therapeutic response or predict drug induced liver injury.Nevertheless,the usefulness of metabolomics is often not understood by clinicians,especially the concept of metabolomics profiling or fingerprinting.In the present work,after a concise description of the different techniques and processes used in metabolomics,we will review the main research on this subject by focusing specifically on in vitro proton nuclear magnetic resonance spectroscopy based metabolomics approaches in human studies.We will first consider the clinical point of view enlighten physicians on this new approach and emphasis its future use in clinical"routine". 展开更多
关键词 Metabolomics In VITRO nuclear magneticresonance spectroscopy LIVER DISEASES CIRRHOSIS
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Substituent, Temperature and Solvent Effects on the Keto-Enol EQUILIBRIUM in <i>&beta;</i>-Ketoamides: A Nuclear Magnetic Resonance Study
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作者 Sergio L. Laurella Manuel González Sierra +1 位作者 Jorge J. P. Furlong Patricia E. Allegretti 《Open Journal of Physical Chemistry》 2013年第4期138-149,共12页
Substituent, temperature and solvent effects on tautomeric equilibria in several β-ketoamides have been investigated by means of nuclear magnetic resonance spectroscopy (NMR). Keto-enol equilibrium predominates over ... Substituent, temperature and solvent effects on tautomeric equilibria in several β-ketoamides have been investigated by means of nuclear magnetic resonance spectroscopy (NMR). Keto-enol equilibrium predominates over the amide-imidol one. The relative stability of the individual tautomers and the corresponding equilibrium shifts are explained considering electronic and steric effects and tautomer stabilization via internal hydrogen bonds. In solution, these compounds exist mainly as ketoamide and Z-enolamide tautomers, both presenting intramolecular hydrogen bonds. 展开更多
关键词 β-Ketoamides Keto-Enol EQUILIBRIUM nuclear magnetic resonance spectroscopy
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Overview and progress of X-nuclei magnetic resonance imaging in biomedical studies 被引量:2
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作者 Gengxin Wang Hongyi Yang +3 位作者 Juan Li Jie Wen Kai Zhong Changlin Tian 《Magnetic Resonance Letters》 2023年第4期327-343,共17页
Proton nuclear(^(1)H)is the observed nucleus on which most magnetic resonance imaging(MRI)applications depend.Most traditional^(1)H MRI can provide structural and functional information about organisms,while various n... Proton nuclear(^(1)H)is the observed nucleus on which most magnetic resonance imaging(MRI)applications depend.Most traditional^(1)H MRI can provide structural and functional information about organisms,while various non-proton nuclei(X-nuclei)MRI can provide more metabolic information.However,due to the relatively poor signal-to-noise ratio(SNR)of X-nuclei MRI,their applications are quite rare compared to^(1)H.Benefit from the rapid developments of MRI hardware and software technologies,X-nuclei MRI has recently attracted increasing interests in biomedical research.This review firstly introduces some current methods to improve the SNR of X-nuclei MRI.Secondly,this review describes biomedical applications of X-nuclei MRI,especially focusing on the current use of X-nuclei(^(13)C,^(17)O,^(19)F,^(23)Na and^(31)P)MRI to study related diseases in different organs,including the brain,liver,kidney,heart and bone.Finally,perspectives studies on X-nuclei imaging and its potential applications are described in biomedical research. 展开更多
关键词 magnetic resonance imaging X-nuclei BIOMEDICAL ^(13)C ^(17)O ^(19)F ^(23)Na ^(31)p
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3.0T 31P MR spectroscopy in assessment of response to antiviral therapy for chronic hepatitis C 被引量:2
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作者 Chun-Yu Zhang Qian Zhang +1 位作者 Hui-Mao Zhang Hai-Shan Yang 《World Journal of Gastroenterology》 SCIE CAS 2014年第8期2107-2112,共6页
AIM: To investigate the utility of phosphorus-31 (31P) magnetic resonance spectroscopy (MRS) as a noninvasive test for assessment of response to interferon and ribavirin treatment in patients with different severities... AIM: To investigate the utility of phosphorus-31 (31P) magnetic resonance spectroscopy (MRS) as a noninvasive test for assessment of response to interferon and ribavirin treatment in patients with different severities of hepatitis C virus infection. 展开更多
关键词 31p magnetic resonance spectroscopy Hepatitis C Antiviral therapy
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Molecular structure characterization of middle-high rank coal via^(13)C NMR,XPS,and FTIR spectroscopy
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作者 Xiao-ming Ni Jing-shuo Zhang +1 位作者 Xiao-kai Xu Bao-yu Wang 《China Geology》 CAS CSCD 2024年第4期702-713,共12页
Elemental analysis,nuclear magnetic resonance carbon spectroscopy(^(13)C-NMR),X-ray photoelectron spectroscopy(XPS)and Fourier transform infrared spectroscopy(FTIR)experiments were carried out to determine the existen... Elemental analysis,nuclear magnetic resonance carbon spectroscopy(^(13)C-NMR),X-ray photoelectron spectroscopy(XPS)and Fourier transform infrared spectroscopy(FTIR)experiments were carried out to determine the existence of aromatic structure,heteroatom structure and fat structure in coal.MS(materials studio)software was used to optimize and construct a 3D molecular structure model of coal.A method for establishing a coal molecular structure model was formed,which was“determination of key structures in coal,construction of planar molecular structure model,and optimization of three-dimensional molecular structure model”.The structural differences were compared and analyzed.The results show that with the increase of coal rank,the dehydrogenation of cycloalkanes in coal is continuously enhanced,and the content of heteroatoms in the aromatic ring decreases.The heteroatoms and branch chains in the coal are reduced,and the structure is more orderly and tight.The stability of the structure is determined by theπ-πinteraction between the aromatic rings in the nonbonding energy EN.Key Stretching Energy The size of EB determines how tight the structure is.The research results provide a method and reference for the study of the molecular structure of medium and high coal ranks. 展开更多
关键词 Molecular structure model Carbon-13 nuclear magnetic resonance(NMR) X-ray photoelectron spectroscopy(XpS) Fourier transform infrared spectroscopy(FTIR) COAL
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基于^(31)P核磁共振探究退化高寒湿地土壤磷素演变特征及影响因素
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作者 罗原骏 蒲玉琳 +2 位作者 袁大刚 李亚丽 钱虹宇 《草业学报》 CSCD 北大核心 2024年第2期1-12,共12页
探明高寒湿地不同退化程度土壤磷素组成特征及其形态演变的驱动机制对于湿地生态恢复过程中养分和碳汇的科学管理具有重要意义。以若尔盖自然保护区内相对原生沼泽(RPM)、轻度退化沼泽(LDM)、中度退化沼泽(MDM)、重度退化沼泽(HDM)为对... 探明高寒湿地不同退化程度土壤磷素组成特征及其形态演变的驱动机制对于湿地生态恢复过程中养分和碳汇的科学管理具有重要意义。以若尔盖自然保护区内相对原生沼泽(RPM)、轻度退化沼泽(LDM)、中度退化沼泽(MDM)、重度退化沼泽(HDM)为对象,采用液相31P核磁共振波谱技术、分段式结构方程模型研究了高寒湿地退化过程中土壤磷素演变特征及主要影响因素。结果表明,高寒湿地退化导致植物群落组成由湿生向中生演替,土壤有机质与氮含量降低。正磷酸盐和磷酸单酯含量随湿地退化呈先增加后降低的趋势,其中正磷酸盐在HDM中相较于RPM降低46.45%,磷酸单酯在LDM、MDM和HDM中相较于RPM分别增加27.02%、54.96%和41.74%;焦磷酸盐和磷酸二酯含量随湿地退化逐渐降低。分段式结构方程模型的拟合结果显示,植被生物量、土壤养分和微生物活性是影响湿地土壤磷素演变的主要因素,其中微生物活性是正磷酸盐、焦磷酸盐和磷酸二酯的正向影响因子,是磷酸单酯的负向影响因子,植物生物量是正磷酸盐和磷酸二酯的正向影响因子,土壤养分虽对各形态磷没有直接影响,但可通过调控微生物活性间接影响焦磷酸盐和磷酸二酯含量。综上所述,湿地退化通过改变植物群落组成、降低土壤养分含量和微生物活性,促进了土壤磷酸二酯分解;重度退化湿地土壤磷有效性因磷酸单酯矿化能力减弱、正磷酸盐含量降低而减小。 展开更多
关键词 若尔盖高原 高寒湿地退化 液相^(31)p核磁共振 磷形态
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^(31)P核磁共振光谱及薄层色谱分析针剂大豆卵磷脂 被引量:26
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作者 施邑屏 黎燕斌 +2 位作者 孙玲玲 冯青 李祖义 《分析化学》 SCIE EI CAS CSCD 北大核心 1991年第7期733-736,共4页
本文采用薄层色谱(TLC)扫描法和^(31)p核磁共振光谱(^(31)P NMR)定性及定量地分析了针剂大豆卵磷脂的组份,薄层色谱采用钼蓝显色后在700nm扫描定量结果与^(31)p核磁共振光谱结果基本一致。这二种方法可应用于其他各种生物材料的磷脂分... 本文采用薄层色谱(TLC)扫描法和^(31)p核磁共振光谱(^(31)P NMR)定性及定量地分析了针剂大豆卵磷脂的组份,薄层色谱采用钼蓝显色后在700nm扫描定量结果与^(31)p核磁共振光谱结果基本一致。这二种方法可应用于其他各种生物材料的磷脂分析。而^(31)P核磁共振光谱分析与其他分析磷脂化合物方法相比较,则更具有快速、灵敏、准确性。 展开更多
关键词 大豆卵磷脂 针剂 NMR TLC 测定
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Grade classification of neuroepithelial tumors using high-resolution magic-angle spinning proton nuclear magnetic resonance spectroscopy and pattern recognition 被引量:5
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作者 CHEN WenXue LOU HaiYan +9 位作者 ZHANG HongPing NIE Xiu LAN WenXian YANG YongXia XIANG Yun QI JianPin LEI Hao TANG HuiRu CHEN FenEr DENG Feng 《Science China(Life Sciences)》 SCIE CAS 2011年第7期606-616,共11页
Clinical data have shown that survival rates vary considerably among brain tumor patients,according to the type and grade of the tumor.Metabolite profiles of intact tumor tissues measured with high-resolution magic-an... Clinical data have shown that survival rates vary considerably among brain tumor patients,according to the type and grade of the tumor.Metabolite profiles of intact tumor tissues measured with high-resolution magic-angle spinning proton nuclear magnetic resonance spectroscopy (HRMAS 1H NMRS) can provide important information on tumor biology and metabolism.These metabolic fingerprints can then be used for tumor classification and grading,with great potential value for tumor diagnosis.We studied the metabolic characteristics of 30 neuroepithelial tumor biopsies,including two astrocytomas (grade I),12 astrocytomas (grade II),eight anaplastic astrocytomas (grade III),three glioblastomas (grade IV) and five medulloblastomas (grade IV) from 30 patients using HRMAS 1H NMRS.The results were correlated with pathological features using multivariate data analysis,including principal component analysis (PCA).There were significant differences in the levels of N-acetyl-aspartate (NAA),creatine,myo-inositol,glycine and lactate between tumors of different grades (P<0.05).There were also significant differences in the ratios of NAA/creatine,lactate/creatine,myo-inositol/creatine,glycine/creatine,scyllo-inositol/creatine and alanine/creatine (P<0.05).A soft independent modeling of class analogy model produced a predictive accuracy of 87% for high-grade (grade III-IV) brain tumors with a sensitivity of 87% and a specificity of 93%.HRMAS 1H NMR spectroscopy in conjunction with pattern recognition thus provides a potentially useful tool for the rapid and accurate classification of human brain tumor grades. 展开更多
关键词 neuroepithelial tumor grade classification high-resolution magic-angle spinning nuclear magnetic resonance (HRMASNMR) spectroscopy METABONOMICS pattern recognition
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人早幼粒白血病细胞HL-60胞内pH的^(31)P核磁共振研究 被引量:9
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作者 黄荣清 颜贤忠 +1 位作者 骆传环 杜泽涵 《分析化学》 SCIE EI CAS CSCD 北大核心 2003年第2期201-204,共4页
建立了无损伤性测定HL 60细胞胞内pH的31 P NMR方法。细胞内无机磷 (Pi)的化学位移对pH非常敏感 ,随pH变化而变化 ,通过测定其化学位移进而能间接确定细胞内的pH。HL 60细胞的31 P核磁共振谱由Pi、ATP等的共振峰组成。根据Pi 峰的化学... 建立了无损伤性测定HL 60细胞胞内pH的31 P NMR方法。细胞内无机磷 (Pi)的化学位移对pH非常敏感 ,随pH变化而变化 ,通过测定其化学位移进而能间接确定细胞内的pH。HL 60细胞的31 P核磁共振谱由Pi、ATP等的共振峰组成。根据Pi 峰的化学位移对HL 60细胞内pH进行了测定。HL 60细胞内Pi 峰的化学位移为 5 .78± 0 .0 1 ,计算得到细胞内pH值为 6.1 6±0 .0 1。31 P核磁共振能在测定细胞胞内pH的同时 ,观测到细胞内多种含磷小分子代谢物 。 展开更多
关键词 R73HL-60细胞 白血病 pH值 核磁共振 细胞代谢 分析
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土壤磷形态组分分级及^(31)P-NMR技术应用研究进展 被引量:20
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作者 汪洪 宋书会 +1 位作者 张金尧 刘云霞 《植物营养与肥料学报》 CAS CSCD 北大核心 2017年第2期512-523,共12页
农田生态系统中土壤磷形态转化,影响土壤磷对作物的有效供应。土壤磷分为无机磷和有机磷两大部分。化学连续提取法(chemical sequential fractionation,CSF)研究土壤磷形态分级,采用不同的化学提取剂,分级提取土壤中组成或分解能力接近... 农田生态系统中土壤磷形态转化,影响土壤磷对作物的有效供应。土壤磷分为无机磷和有机磷两大部分。化学连续提取法(chemical sequential fractionation,CSF)研究土壤磷形态分级,采用不同的化学提取剂,分级提取土壤中组成或分解能力接近的有机无机含磷化合物,是目前表征土壤磷素形态的重要方法。但该方法虽历经改进,仍难以确切反映土壤磷的实际组成,提取的不同磷形态间存在重叠,有机磷和无机磷组分分级存在一定的误差;不同分级磷组分对作物的有效性,需谨慎评估。核磁共振波谱技术(nuclear magnetic resonance,NMR)根据核磁共振波谱图上共振峰的位置、强度和精细结构来研究土壤中含磷化合物的分子结构。液相31PNMR可以同吋检测出土壤中多种磷组分,如正磷酸盐、磷酸单酯、磷酸二酯、膦酸脂、焦磷酸盐和多聚磷酸盐,识别土壤提取物磷形态,可将有机磷与无机磷分开。本文综述了应用31P-NMR技术研究土壤磷形态组分的一些进展,总结了样品制备过程、NMR测试参数及在土壤磷形态转化研究中的应用。二维31P-NMR技术发展为鉴定分析土壤中更多种类的含磷化合物提供了契机。 展开更多
关键词 土壤磷形态 化学连续提取法 土壤磷组分 ^31p-核磁共振波谱技术
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