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MicrobIdentifier: A Microbial Identification Software Based on Mass-Spectrometry
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作者 Feng LIU Lu LI +2 位作者 Chi ZHANG Lingbing WANG Pei LI 《Journal of Software Engineering and Applications》 2009年第3期206-208,共3页
As the technology of microbial identification by mass cataloging has been widely used, we have developed the micro-bial identification software, MicrobIdentifier, which integrates and automates different steps in the ... As the technology of microbial identification by mass cataloging has been widely used, we have developed the micro-bial identification software, MicrobIdentifier, which integrates and automates different steps in the procedure of rapid species identification based on mass-spectrometry. This software is written in Java for cross-platform intention. 展开更多
关键词 MICROBIAL IDENTIFICATION mass-spectrometry
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Molecular Fingerprints of Soil Organic Matter in a Typical Freshwater Wetland in Northeast China 被引量:4
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作者 LI Zhe ZHANG Zhongsheng +5 位作者 XUE Zhenshan SONG Xiaolin ZHANG Hongri WU Haitao JIANG Ming LYU Xianguo 《Chinese Geographical Science》 SCIE CSCD 2019年第4期700-711,共12页
Natural wetlands are known to store huge amounts of organic carbon in their soils. Despite the importance of this storage,uncertainties remain about the molecular characteristics of soil organic matter(SOM), a key fac... Natural wetlands are known to store huge amounts of organic carbon in their soils. Despite the importance of this storage,uncertainties remain about the molecular characteristics of soil organic matter(SOM), a key factor governing the stability of soil organic carbon(SOC). In this study, the molecular fingerprints of SOM in a typical freshwater wetland in Northeast China were investigated using pyrolysis gas-chromatography/mass-spectrometry technology(Py-GC/MS). Results indicated that the SOC, total nitrogen(TN),and total sulfur contents of the cores varied between 16.88% and 45.83%, 0.93% and 2.82%, and 1.09% and 3.79%, respectively. The bulk δ^13C and δ^15N varied over a range of 9.85‰, between –26.85‰ and –17.00‰, and between –0.126‰ and 1.002‰, respectively. A total of 134 different pyrolytic products were identified, and they were grouped into alkyl(including n-alkanes(C:0) and n-alkenes(C:1),aliphatics(Al), aromatics(Ar), lignin(Lg), nitrogen-containing compounds(Nc), polycyclic aromatic hydrocarbons(PAHs), phenols(Phs), polysaccharides(Ps), and sulfur-containing compounds(Sc). On average, Phs moieties accounted for roughly 24.11% peak areas of the total pyrolysis products, followed by Lg(19.27%), alkyl(18.96%), other aliphatics(12.39%), Nc compounds(8.08%), Ps(6.49%), aromatics(6.32%), Sc(3.26%), and PAHs(1.12%). Soil organic matter from wetlands had more Phs and Lg and less Nc moieties in pyrolytic products than soil organic matters from forests, lake sediments, pastures, and farmland.δ^13 C distribution patterns implied more C3 plant-derived soil organic matter, but the vegetation was in succession to C4 plant from C3 plant. Significant negative correlations between Lg or Ps proportions and C3 plant proportions were observed. Multiple linear analyses implied that the Ar and Al components had negative effects on SOC. Alkyl and Ar could facilitate ratios between SOC and total nitrogen(C/N), while Al plays the opposite role. Al was positively related to the ratio of dissolved organic carbon(DOC) to SOC. In summary, SOM of wetlands might characterize by more Phs and lignin and less Nc moieties in pyrolytic products. The use of Pyrolysis gas-chromatography/mass-spectrometry(Py-GC/MS) technology provided detailed information on the molecular characteristics of SOM from a typical freshwater wetland. 展开更多
关键词 molecular fingerprint soil organic matter pyrolysis gas-chromatography/mass-spectrometry FRESHWATER MARSH NORTHEAST China
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In situ Lu–Hf phosphate geochronology:Progress towards a new tool for space exploration 被引量:1
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作者 Stijn Glorie Thomas Burke +3 位作者 Martin Hand Alexander Simpson Sarah Gilbert Benjamin Wade 《Geoscience Frontiers》 SCIE CAS CSCD 2022年第3期164-167,共4页
Geochronology is fundamental to understanding planetary evolution.However,as space exploration continues to expand,traditional dating methods,involving complex laboratory processes,are generally not realistic for unma... Geochronology is fundamental to understanding planetary evolution.However,as space exploration continues to expand,traditional dating methods,involving complex laboratory processes,are generally not realistic for unmanned space applications.Campaign-style planetary exploration missions require dating methods that can(1)rapidly resolve age information on small samples,(2)be applied to minerals common in mafic rocks,and(3)be based on technologies that could be installed on future rover systems.We demonstrate the application of rapid in situ microanalytical Lu–Hf phosphate geochronology using samples of pallasite meteorites,which are representative examples of the deep interiors of differentiated planetoids that are generally difficult to date.Individual pallasites were dated by laser ablation tandem mass-spectrometry(LA-ICP-MS/MS),demonstrating a rapid novel method for exploring planetary evolution.Derived formation ages for individual pallasites agree with traditional methods and have<2%uncertainty,opening an avenue of opportunity for remote micro-analytical space exploration. 展开更多
关键词 Pallasite meteorites Lu-Hf geochronology Laser ablation tandem mass-spectrometry Micro-analytical planetary exploration
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Determination and Quantification of Trace Elements, by ICP_MS, in the River Water of Sarzhal and Akzhar Villages 被引量:1
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作者 Zhanibek Yessimbekov Duyssembaev Sergazy +2 位作者 Dilraba Iminova Eleonora Okushanova Marilyne Stuart 《Journal of Environmental Protection》 2013年第10期1067-1070,共4页
In the present study, trace elements present in the river waters of Sarzhal and Akzhar region were measured using inductively coupled plasma mass spectrometry (ICP-MS). The reason for monitoring trace elements at thos... In the present study, trace elements present in the river waters of Sarzhal and Akzhar region were measured using inductively coupled plasma mass spectrometry (ICP-MS). The reason for monitoring trace elements at those two locations is to verify water quality. The village of Sarzhal is situated in an area that has been affected by weapon testing and continues to receive inputs of contaminants (including radionuclides). The concentrations of trace elements in the river water of Sarzhal and Akzhar villages were generally found to be within allowable levels. However, the concentrations of Na 251.56 mg/l, Cr 3.26 μg/l, P 64.56 μg/l and Se 18.162 μg/l in the river of Akzhar were found to be higher than the maximum allowable concentrations (MAC). In Sarzhal, the level of Al 6.66 mg/l, Cr 5.04 μg/l and P 13.44 μg/l exceeded the MAC values. 展开更多
关键词 RIVER Water TRACE ELEMENT mass-spectrometry Sarzhal Akzhar
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Exorphins in urine from schizoaffective psychotics
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作者 Dag Tveiten Karl L. Reichelt 《Open Journal of Psychiatry》 2012年第3期220-227,共8页
Hyperpeptiduria and opioid excess have been reported in schizophrenia. According to Prof. Dr. L. Lindstrom, Sweden opioids may explain the patho-physiology of this syndrome. Therefore it is critical to elucidate the p... Hyperpeptiduria and opioid excess have been reported in schizophrenia. According to Prof. Dr. L. Lindstrom, Sweden opioids may explain the patho-physiology of this syndrome. Therefore it is critical to elucidate the presence and nature of opioids in schizophrenia and diagnostic sub groups. First morning urine from untreated schizoaffective patients (ICD-10: F 25.1) was separated on HPLC and peaks that elute where different opioid standards appear, freeze dried, re-dissolved in methanol/water (50/50) and 10mM formic acid. Mass spectrometry and MS/MS or fragmentation mass spectrometry was performed. We found fragmentation pattern of beta-casomorphin 1-3 and 1-4 (bovine) identical to synthetic standards from Bachem. The aggregation tendency of peptides was much in evidence. The reported exorphins were found in the urine from 8 of 12 untreated schizoaffective patients. 展开更多
关键词 Exorphins SCHIZOAFFECTIVE PEPTIDE mass-spectrometry
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Peptides and Exorphins in the Autism Spectrum
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作者 Dag Tveiten Adrian Finvold +1 位作者 Marthe Andersson Karl LReichelt 《Open Journal of Psychiatry》 2014年第3期275-287,共13页
Problem: Some researchers have not found the opioids in urine of autistic children. We have therefore looked at this problem again. Method: Mass spectrometry and fragmentation mass spectrometry (MS/MS) have been carri... Problem: Some researchers have not found the opioids in urine of autistic children. We have therefore looked at this problem again. Method: Mass spectrometry and fragmentation mass spectrometry (MS/MS) have been carried out on peaks from the HPLC that show co-chromatography with synthetic standards and peaks that are shared by different autistic children. Results: In quickly frozen urine we find the presence of exorphins, and can also demonstrate a rather fast break down at room temperature of these peptides in urine. Conclusion: Exorphins are present in urine in autistic children, but must be protected against break down and aggregation by fast freezing or acetic acid and adjusting declustering potential and collision potential during mass-spectroscopy. Specific antibody increases and the effect of removing precursor proteins from the diet reinforce this view. 展开更多
关键词 AUTISM BEHAVIOR DIET Exorphins mass-spectrometry PEPTIDES
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Etiology of invasive candidosis agents in Russia: a multicenter epidemiological survey 被引量:1
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作者 N.V. Vasilyeva E.R. Raush +5 位作者 M.V. Rudneva T.S. Bogomolova A.E. Taraskina Yong Fang Fengmin Zhang N.N. Klimko 《Frontiers of Medicine》 SCIE CAS CSCD 2018年第1期84-91,共8页
A multicenter prospective epidemiological survey on the etiologic agents of invasive candidosis was conducted in Russia in the period of 2012-2014. Samples were collected from 284 patients with invasive candidosis and... A multicenter prospective epidemiological survey on the etiologic agents of invasive candidosis was conducted in Russia in the period of 2012-2014. Samples were collected from 284 patients with invasive candidosis and Candida species isolated by culture. The species were identified by DNA sequencing and MALDI-TOF mass- spectrometry. A total of 322 isolates were recovered, in which 96% of Candida species belonged to six major species, namely, C. albicans (43.2%), C. parapsilosis (20.2%), C. glabrata (11.5%), C. tropicalis (9.6%), C. krusei (6.2%), and C. guilliermondii (5.3%). Most Candida species were isolated from blood samples (83.23%). Notably, the prevalence rate of C. albicans reduced from 52.38% to 32.79% (2012 vs. 2014) (P = 0.01) whereas that of non-C. albicans increased from 47.62% (2012) to 67.21% (2014) (P〈 0.01). Species distribution differed among geographical regions; specifically, the prevalence rate of C. albicans as an etiologic agent of invasive candidosis in Siberian Federal region was significantly higher than that in other Federal regions. Results indicated a shift from C. albicans to non-C, albicans. Therefore, a detailed investigation on the contributing factors and appropriate treatment of invasive candidosis is needed. 展开更多
关键词 prevalence Candida species invasive candidosis NOSOCOMIAL ETIOLOGY MALDI-TOF mass-spectrometry CANDIDEMIA
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A new photolabeling probe for efficient enrichment and deep profiling of cell surface membrane proteome by mass spectrometry
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作者 Yuanyuan Li Chaoshuang Xia +6 位作者 Hongxian Zhao Yuping Xie Yangjun Zhang Wanjun Zhang Yongliang Yu Jianhua Wang Weijie Qin 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第2期279-283,共5页
The cell surface membrane proteome is a class of proteins encoded by ~25% of all protein-coding genes in living organisms and plays a key role in mediating communication between the cells and their surrounding environ... The cell surface membrane proteome is a class of proteins encoded by ~25% of all protein-coding genes in living organisms and plays a key role in mediating communication between the cells and their surrounding environment. However, most cell surface membrane proteins(CSMPs) are naturally expressed at very low levels compared with intracellular proteins. The difficulties in their purification with high specificity further hinder the understanding of their structure and function. In this study, we developed a new photolabeling probe to achieve efficient tagging and facile enrichment of the CSMPs. The probe is composed of a lipid tail for cell surface localization, a polyethylene glycol(PEG) spacer for increased water solubility, two 4-(N-maleimido)benzophenone(MBP) groups for UV-active tagging of the CSMPs, and a biotin tag for subsequent isolation. Application of this photolabeling probe resulted in the successful enrichment and identification of 3098 annotated CSMPs in HT22 cells with close to 70% selectivity. The proposed photolabeling probe and enrichment strategy were demonstrated to be a powerful method for deep cell surface proteome profiling, representing one of the largest groups of current drug targets. 展开更多
关键词 Cell surface membrane proteins Photolabeling probe ENRICHMENT mass-spectrometry PROTEOMICS DERIVATIZATION
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