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Vermiform Ni@CNT derived from one-pot calcination of Ni-MOF precursor for improving hydrogen storage of MgH_(2)
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作者 Zi-yin DAI Bing ZHANG +10 位作者 Hideo KIMURA Li-rong XIAO Rong-han LIU Cui NI Chuan-xin HOU Xue-qin SUN Yu-ping ZHANG Xiao-yang YANG Rong-hai YU Wei DU Xiu-bo XIE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2629-2644,共16页
The Ni-coated carbon nanotubes(Ni@CNT)composite was synthesized by the facile“filtration+calcination”of Ni-based metal−organic framework(MOF)precursor and the obtained composite was used as a catalyst for MgH_(2).Mg... The Ni-coated carbon nanotubes(Ni@CNT)composite was synthesized by the facile“filtration+calcination”of Ni-based metal−organic framework(MOF)precursor and the obtained composite was used as a catalyst for MgH_(2).MgH_(2)was mixed evenly with different amounts of Ni@CNT(2.5,5.0 and 7.5,wt.%)through ball milling.The MgH_(2)−5wt.%Ni@CNT can absorb 5.2 wt.%H_(2)at 423 K in 200 s and release about 3.75 wt.%H_(2)at 573 K in 1000 s.And its dehydrogenation and rehydrogenation activation energies are reduced to 87.63 and 45.28 kJ/mol(H_(2)).The in-situ generated Mg_(2)Ni/Mg_(2)NiH4 exhibits a good catalytic effect due to the provided more diffusion channels that can be used as“hydrogen pump”.And the presence of carbon nanotubes improves the properties of MgH_(2)to some extent. 展开更多
关键词 Mg-based hydrogen storage material activation energy Ni-loaded carbon nanotubes catalyst mechanism
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负载型磷钨杂多酸的制备及在醚化反应中的应用 被引量:1
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作者 马骏 王海彦 +1 位作者 杨澎 刘娜 《沈阳化工》 2000年第4期189-190,204,共3页
以活性炭为载体,制备了催化剂H3PW12O40(PW12)/C,并进行了混合烯烃与甲醇的醚化反应。研究了制备条件、PW12负载量对催化活性的影响,并对醚化反应条件进行了系统考察。
关键词 负载型 磷钨杂多酸 活性炭载体 叔碳烯烃 醚化反应 管化剂
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Photocatalytic Degradation of Phenol over MWCNTs-TiO2 Composite Catalysts with Different Diameters
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作者 李晨 汪文栋 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第4期423-428,448,共7页
Titania-based composite catalysts were prepared through a sol-gel route employing multi-walled carbon nanotubes with different diameters. The materials were characterized using thermogravimetric analysis, nitrogen ads... Titania-based composite catalysts were prepared through a sol-gel route employing multi-walled carbon nanotubes with different diameters. The materials were characterized using thermogravimetric analysis, nitrogen adsorption-desorption isotherm, powder X-ray diffraction, scanning electron microscopy, and diffuse reflectance UV-Vis absorption spectra. The application of the catalysts to photocatalytic degradation of phenol was tested under UV-Vis irradiation. A synergetic effect on phenol removal was observed in case of composite catalysts, which was evaluated in terms of apparent rate constant, total organic carbon removal and photonic efficiency. 展开更多
关键词 Photocatalytic degradation PHENOL Titanium dioxide Multi-walled carbon nanotube Composite catalyst
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Meta-analysis of the Use of ACEI for Inhibiting Albuminuria in Diabetic Patients
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作者 吴浩 翟所迪 卢荣枝 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第2期142-150,共9页
Aim To examine whether AER(albumin excretion rate) in normotensive diabeticpatients can be effectively inhibited by ACEI. Methods Literature on randomized controlled trials ofACEI for inhibiting AER in normotensive di... Aim To examine whether AER(albumin excretion rate) in normotensive diabeticpatients can be effectively inhibited by ACEI. Methods Literature on randomized controlled trials ofACEI for inhibiting AER in normotensive diabetic patients was searched. The electronic databasesretrieved were Medline (1980 ― 2003), Embase database (1980 ― 2000), Cochrane Library, CL( 1980 ―2004), CBMdisc( 1980 ― 2002), and IPA( 1980 ― 2002). Seven studies were chosen. Data werecombined by Revman 4.2. Results: The pooled effect of change in AER is - 56.31 μg·min^(-1)) [ -81.96, -30.66] (P<0.0001). According to the analysis of subgroups, the pooled effects of 1 - 5 yearsare - 11.97 μg·min^(-1)[-22.04, -1.89] (P = 0.02), -28.01 μg·min^(-1)[-34.50, -21.52](P<0.00001), -43.24 μg·min^(-1) [ -57.15, -29.32] (P< 0.00001), -61.65 μg·min^(-1)[77.77,-45.54] (P< 0.00001), and -98.41 μg·min^(-1)[-162.02,-34.79] (P = 0.002). Regarding progression toclinincal proteinuria as end-point, the pooled Peto OR =0.27 [0.18,0.40] (95% CI), P < 0.00001.According to the analysis of subgroups, the pooled effects of 2 and 5 years are Peto OR = 0.30[0.18,0.51] (P<0.00001) and Peto OR=0.25 [0.13, 0.50](P<0.0001). Publication bias is small.Conclusion In normotensive diabetic patients, ACEI inhibits AER effectively and reduces theprobability of progression of microalbuminuria to clinical proteinuria. 展开更多
关键词 angiotensin-converting enzyme inhibitor diabetes mellitus MICROALBUMINURIA urine protein META-ANALYSIS
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JAK-STAT pathway in carcinogenesis:Is it relevant to cholangiocarcinoma progression? 被引量:15
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作者 Olga V Smirnova Tatiana Yu Ostroukhova Roman L Bogorad 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第48期6478-6491,共14页
The features of JAK-STAT signaling in liver cells are discussed in the current review. The role of this signaling cascade in carcinogenesis is accentuated. The possible involvement of this pathway and alteration of it... The features of JAK-STAT signaling in liver cells are discussed in the current review. The role of this signaling cascade in carcinogenesis is accentuated. The possible involvement of this pathway and alteration of its elements are compared for normal cholangiocytes, cholangiocarcinoma predisposition and development. Prolactin and interleukin-6 are described in detail as the best studied examples. In addition, the non-classical nuclear translocation of cytokine receptors is discussed in terms of its possible implication to cholangiocarcinoma development. 展开更多
关键词 CHOLANGIOCARCINOMA Janus tyrosine Kinases Signal Transducers and Activators of Transcription PROLACTIN INTERLEUKIN-6 Cytokine receptors Receptor tyrosine kinases
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Multidisciplinary management of gastric and gastroesophageal cancers 被引量:17
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作者 Markus Moehler Orestis Lyros +2 位作者 Ines Gockel Peter R Galle Hauke Lang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第24期3773-3780,共8页
Carcinomas of the stomach and gastroesophageal junction are among the five top leading cancer types worldwide. In spite of radical surgical R0 resections being the basis of cure of gastric cancer, surgery alone provid... Carcinomas of the stomach and gastroesophageal junction are among the five top leading cancer types worldwide. In spite of radical surgical R0 resections being the basis of cure of gastric cancer, surgery alone provides long-term survival in only 30% of patients with advanced International Union Against Cancer (UICC) stages in Western countries because of the high risk of recurrence and metachronous metastases. However, recent large phase-Ⅲ studies improved the diagnostic and therapeutic options in gastric cancers, indicating a more multidisciplinary management of the disease. Multimodal strategies combining different neoadjuvant and/or adjuvant protocols have clearly improved the gastric cancer prognosis when combined with surgery with curative intention. In particular, the perioperative (neoadjuvant, adjuvant) chemotherapy is now a well-established new standard of care for advanced tumors. Adjuvant therapy alone should be carefully discussed after surgical resection, mainly in individual patients with large lymph node positive tumors when neoadjuvant therapy could not be done. The palliative treatment options have also been remarkably improved with new chemotherapeutic agents and will further be enhanced with targeted therapies such as different monoclonal antibodies. This article reviews the most relevant literature on the multidisciplinary management of gastric and gastroesophageal cancer, and discusses future strategies toimprove Iocoregional failures. 展开更多
关键词 Gastric cancer CHEMOTHERAPY CHEMORADIATION ADJUVANT NEOADJUVANT
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Synthesis of Higher Alcohols from Syngas over Alkali Promoted K-Co-Mo Catalysts Supported on Multi-walled Carbon Nanotubes
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作者 姬丽丽 李欢 +4 位作者 张伟 孙松 高琛 鲍骏 马运生 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第3期333-338,I0002,共7页
A series of carbon nanotubes-supported K-Co-Mo catalysts were prepared by a sol-gel method combined with incipient wetness impregnation. The catalyst structures were characterized by X-ray diffraction, N2 adsorption-d... A series of carbon nanotubes-supported K-Co-Mo catalysts were prepared by a sol-gel method combined with incipient wetness impregnation. The catalyst structures were characterized by X-ray diffraction, N2 adsorption-desorption, transmission electron microscopy and H2-TPD, and its catalytic performance toward the synthesis of higher alcohols from syngas was investigated. The as-prepared catalyst particles had a low crystallization degree and high dispersion on the outer and inner surface of CNTs. The uniform mesoporous structure of CNTs increased the diffusion rate of reactants and products, thus promoting the reaction conversion. Furthermore, the incorporation of CNTs support led to a high capability of hydrogen absorption and spillover and promoted the formation of alkyl group, which served as the key intermediate for the alcohol formation and carbon chain growth. Benefiting from these characteristics, the CNTs supported Mo-based catalyst showed the excellent catalytic performance for the higher alcohols synthesis as compared to the unsupported catalyst and activated carbon supported catalyst. 展开更多
关键词 CO hydrogenation Higher alcohol synthesis Mo-based catalyst CNTs support
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Synthesis of Polyketone by Copolymerization of Styrene and CO Using Carbon Nanotube-Complex Pd^(2+) Catalyst 被引量:1
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作者 郭锦棠 肖淼 +1 位作者 王海霞 胡光 《Transactions of Tianjin University》 EI CAS 2014年第2期86-90,共5页
The dipping method was devised to deposit Pd onto carbon nanotube as supported catalyst(Pd/CNT) for the copolymerization of carbon monoxide(CO) and styrene(ST) towards the formation of polyketone(PK).The Pd/CNT was ch... The dipping method was devised to deposit Pd onto carbon nanotube as supported catalyst(Pd/CNT) for the copolymerization of carbon monoxide(CO) and styrene(ST) towards the formation of polyketone(PK).The Pd/CNT was characterized by X-ray photoelectron spectroscopy(XPS),X-ray diffraction(XRD) and high-resolution transmission electron microscopy(HRTEM).The construction and crystallization property of PK were evaluated by Fourier transform infrared spectroscopy(FTIR),13C-nuclear magnetic resonance(NMR) and XRD,respectively.The catalyst showed excellent activity and reusability in promoting the fabrication of PK.It can be recycled 14 times with the highest total catalytic activity of 4 239.64 gPK/(gPd·h) at Pd content of 8.63wt%.The results indicate that the prepared catalyst is effective to catalyze the copolymerization of CO and styrene. 展开更多
关键词 carbon nanotube supported catalyst catalytic activity COPOLYMERIZATION POLYKETONE
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Identification of methylation profile of HOX genes in extrahepatic cholangiocarcinoma 被引量:7
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作者 Yi Shu Bing Wang Ji Wang Jian-Ming Wang Sheng-Quan Zou 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第29期3407-3419,共13页
AIM:To identify methylation profile and novel tumor marker of extrahepatic cholangiocarcinoma(CCA)with high throughout microarray.METHODS:Differential methylation profile was compared between normal bile duct epitheli... AIM:To identify methylation profile and novel tumor marker of extrahepatic cholangiocarcinoma(CCA)with high throughout microarray.METHODS:Differential methylation profile was compared between normal bile duct epithelial cell lines and CCA cell lines by methyl-DNA immunoprecipitation (MeDIP)microarray.Bisulfite-polymerase chain reaction (BSP)was performed to identify the methylated allels of target genes.Expression of target genes was investigated before and after the treatment with DNA demethylating agent.Expression of candidate genes was also evaluated by immunofluorescence in 30 specimens of CCA tissues and 9 normal bile duct tissues.RESULTS:Methylation profile of CCA was identified with MeDIP microarray in the respects of different gene functions and signaling pathways.Interestingly,97 genes with hypermethylated CpG islands in the promoter region were homeobox genes.The top 5 hypermethylated homeobox genes validated by BSP were HOXA2(94.29%),HOXA5(95.38%),HOXA11 (91.67%),HOXB4(90.56%)and HOXD13(94.38%).Expression of these genes was reactivated with 5’-aza2’-deoxycytidine.Significant expression differences were found between normal bile duct and extrahepatic CCA tissues(66.67%-100%vs 3.33%-10%).CONCLUSION:HOXA2,HOXA5,HOXA11,HOXB4 and HOXD13 may work as differential epigenetic biomarkers between malignant and benign biliary tissues. 展开更多
关键词 DNA methylation EPIGENETIC Promoter microarray CHOLANGIOCARCINOMA
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Preparation of Surfactant-Free Pt and PtRu Nanoparticles with High Activity for Methanol Oxidation 被引量:1
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作者 Yao Yao Jun Cai +1 位作者 Yong-li Zheng Yan-xia Chen 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第3期332-336,共5页
A simple and green approach to synthesize highly active electro-catalysts for methanol oxi- dation reaction (MOR) without using any organic agents is described. Pt nanoparticles are directly deposited on the pre-cle... A simple and green approach to synthesize highly active electro-catalysts for methanol oxi- dation reaction (MOR) without using any organic agents is described. Pt nanoparticles are directly deposited on the pre-cleaned and pre-oxidized multiwall carbon nanotubes (MWC- NTs) from Pt salt by using CO as the reductant. MOR activity has been characterized by both cyclic voltammetry and chronoamperometry, the current density and mass specific current at the peak potential (ca. 0.9 V vs. RHE) reaches 11.6 mA/cm^2 and 860 mA/mgpt, respectively. After electro-deposition of Ru onto the Pt/MWCNTs surface, the catalysts show steady state mass specific current of 20 and 80 mA/mgpt at 0.5 and 0.6 V, respectively. 展开更多
关键词 Pt nano-electrocatalyst PtRu nano-electrocatalyst Green synthesis Methanol oxidation reaction Carbon monoxide
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Application of sodium titanate nanotubes doped with vanadium(VNaTNT) as a heterogeneous catalyst for oxidation of sulfides at room temperature 被引量:1
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作者 Mohammad Ali Dadvar Razieh Fazaeli 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第4期494-501,共8页
A heterogeneous titanate nanotube (TNT) catalyst containing TiO2, Na, and V has been synthesized and used in the chemoselective oxidation of sulfides to the corresponding sulfoxides in the presence of 30%H2O2 in wat... A heterogeneous titanate nanotube (TNT) catalyst containing TiO2, Na, and V has been synthesized and used in the chemoselective oxidation of sulfides to the corresponding sulfoxides in the presence of 30%H2O2 in water. Some of the advantages of our method include excellent yields, heterogene‐ous conditions, simplicity, compatibility with a variety of functionalities, and ease of isolation of the products. Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, and N2 adsorption were used for structural and textural charac‐terization of the catalyst (VNaTNT). 展开更多
关键词 SULFIDE SULFOXIDE SULFONE Supported vanadia catalyst NANOTUBE
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Phosphorylated vasodilator-stimulated phosphoprotein is localized on mitotic spindles of the gastric cancer cell line SGC-7901 被引量:2
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作者 Yan Tao Yong-Chang Chen +2 位作者 Ying Wang Zhi-Jian Zhang Wen-Rong Xu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第46期7478-7481,共4页
AIM: To elucidate the localization of vasodilator stimulated phosphoprotein (VASP), a cytoskeletal organizing protein and a substrate of protein kinases A and G in mitotic gastric cancer cells. METHODS: Immunofluo... AIM: To elucidate the localization of vasodilator stimulated phosphoprotein (VASP), a cytoskeletal organizing protein and a substrate of protein kinases A and G in mitotic gastric cancer cells. METHODS: Immunofluorescence microscopy was used to observe the localization of α-tubulin, VASP and Ser157 phosphorylated VASP (p-VASP) in interphase of mitotic gastric cancer of the cell line SGC-7901. RESULTS: Immunofluorescence staining showed that p-VASP but not VASP was co-localized with α-tubulin on spindle poles and fibers in prophase, metaphase and anaphase of the mitotic process of the gastric cancer cell line SGC-7901. H89, an inhibitor of protein kinases A and G, had no effect on the localization of p-VASP on the spindles. CONCLUSION: VASP may play a role in assembling and stabilizing the mitotic spindle of cells, and phosphorylation of the protein is the precondition for it to exert this function. 展开更多
关键词 Phosphorylated vasodilator-stimulated phosphoprotein LOCALIZATION Mitotic spindle Gastric cancer cell
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Antioxidant therapy in the management of acute,chronic and post-ERCP pancreatitis:A systematic review 被引量:10
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作者 Seyed Sajad Mohseni Salehi Monfared Hamed Vahidi +2 位作者 Amir Hossein Abdolghaffari Shekoufeh Nikfar Mohammad Abdollahi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第36期4481-4490,共10页
We systematically reviewed the clinical trials which recruited antioxidants in the therapy of pancreatitis and evaluated whether antioxidants improve the outcome of patients with pancreatitis. Electronic bibliographic... We systematically reviewed the clinical trials which recruited antioxidants in the therapy of pancreatitis and evaluated whether antioxidants improve the outcome of patients with pancreatitis. Electronic bibliographic databases were searched for any studies which investigated the use of antioxidants in the management of acute pancreatitis (AP) or chronic pancreatitis (CP) and in the prevention of post-endoscopic retrograde cholangio-pancreatography (post-ERCP) pancreatitis (PEP) up to February 2009. Twenty-two randomized, placebo-controlled, clinical trials met our criteria and were included in the review. Except for a cocktail of antioxidants which showed improvement in outcomes in three different clinical trials, the results of the administration of other antioxidants in both AP and CP clinical trials were incongruent and heterogeneous.Furthermore, antioxidant therapy including allopurinol and N-acetylcysteine failed to prevent the onset of PEP in almost all trials. In conclusion, the present data do not support a benefit of antioxidant therapy alone or in combination with conventional therapy in the management of AP, CP or PER Further double blind, randomized, placebo-controlled clinical trials with large sample size need to be conducted. 展开更多
关键词 ANTIOXIDANT Post-endoscopic retrogradecholangio-pancreatography pancreatitis Oxidative stress Therapy Acute pancreatitis Chronic pancreatitis
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New Catalytic Proportions for Syntheses of SWNT Bundles (Ropes) and Its Characterization
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作者 DAI Tong DAI Jian-feng 《Semiconductor Photonics and Technology》 CAS 2006年第3期168-172,共5页
The single-walled carbon nanotube(SWNT) bundles and ropes have been prepared by using the anode are discharge plasma to evaporate the graphite rods which contain Fe, Co and Ni powders as catalyst in He atmosphere. M... The single-walled carbon nanotube(SWNT) bundles and ropes have been prepared by using the anode are discharge plasma to evaporate the graphite rods which contain Fe, Co and Ni powders as catalyst in He atmosphere. Many purifying methods are used for the products. It indicates that the synthesis of SWNTs has been greatly affected by the preparation parameters of catalyzer, the buffer gas and its pressure, the arc current intensity, etc. The optimal condition for preparing SWNTs in our case has been proposed. The forming mechanism of the SWNTs bundles and ropes is also studied qualitatively. The evaporated single graphite sheet tends to reduce its active energy. 展开更多
关键词 Single-walled carbon nanotubes Catalyzer Evaporation THERMOGRAVIMETRY
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XAF1 is frequently methylated in human esophageal cancer 被引量:10
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作者 Xiang-Yu Chen Qiao-Yu He Ming-Zhou Guo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第22期2844-2849,共6页
AIM: To explore epigenetic changes in the gene encod- ing X chromosome-linked inhibitor of apoptosis-associ- ated factor 1 (XAF1) during esophageal carcinogenesis. METHODS: Methylation status of XAF1 was detected ... AIM: To explore epigenetic changes in the gene encod- ing X chromosome-linked inhibitor of apoptosis-associ- ated factor 1 (XAF1) during esophageal carcinogenesis. METHODS: Methylation status of XAF1 was detected by methylation-specific polymerase chain reaction (MSP) in four esophageal cancer cell lines (KYSE30, KYSE70, BICl and partially methylated in TE3 cell lines), nine cases of normal mucosa, 72 cases of pri- mary esophageal cancer and matched adjacent tissue. XAF1 expression was examined by semi-quantitative reverse transcriptional polymerase chain reaction and Western blotting before and after treatment with 5-aza- deoxycytidine (5-aza-dc), a demethylating agent. To investigate the correlation of XAF1 expression and methylation status in primary esophageal cancer, immu- nohistochemistry for XAF1 expression was performed in 32 cases of esophageal cancer and matched adjacent tissue. The association of methylation status and clini-copathological data was analyzed by logistic regression. RESULTS: MSP results were as follows: loss of XAF1 expression was found in three of four esophageal cell lines with promoter region hypermethylation (com- pletely methylated in KYSE30, KYSE70 and BIC1 cell lines and partially in TE3 cells); all nine cases of normal esophageal mucosa were unmethylated; and 54/72 (75.00%) samples from patients with esophageal can- cer were methylated, and 25/72 (34.70%) matched adjacent tissues were methylated (75.00% vs 34,70%, z2 = 23.5840, P = 0.000). mRNA level of XAF1 mea- sured with semi-quantitative reverse transcription poly- merase chain reaction was detectable only in TE3 cells, and no expression was detected in KYSE30, KYSE70 or BIC1 cells. Protein expression was not observed in KYSE30 cells by Western blotting before treatment with 5-aza-dc. After treatment, mRNA level of XAF1 was detectable in KYSE30, KYSE70 and BIC1 cells. Protein expression was detected in KYSE30 after treatment with 5-aza-dc. Immunohistochemistry was performed on 32 cases of esophageal cancer and adjacent tissue, and demonstrated XAF1 in the nucleus and cytoplasm. XAF1 staining was found in 20/32 samples of adjacent normal tissue but was present in only 8/32 samples of esophageal cancer tissue (Z2= 9.143, P = 0.002). XAF1 expression was decreased in cancer samples compared with adjacent tissues. In 32 cases of esophageal can- cer, 24/32 samples were methylated, and 8/32 esopha- geal cancer tissues were unmethylated. XAF1 staining was found in 6/8 samples of unmethylated esophageal cancer and 2/24 samples of methylated esophageal cancer tissue. XAF1 staining was inversely correlated with XAF1 promoter region methylation (Fisher's exact test, P = 0.004). Regarding methylation status and clinicopathological data, no significant differences were found in sex, age, tumor size, tumor stage, or metas- tasis with respect to methylation of XAF1 for the 72 tis- sue samples from patients with esophageal cancer. CONCLUSION: XAF1 is frequently methylated in eso- phageal cancer, and XAF1 expression is regulated by promoter region hypermethylation. 展开更多
关键词 X chromosome-linked inhibitor of apoptosis-associated factor 1 Esophageal cancer METHYLATION Methylation-specific polymerase chain reaction Semi-quantitative reverse transcriptional polymerase chainreaction
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Phosphonate-derived nitrogen-doped cobalt phosphate/carbon nanotube hybrids as highly active oxygen reduction reaction electrocatalysts 被引量:6
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作者 Hui Zhao Chen-Chen Weng +3 位作者 Jin-Tao Ren Li Ge Yu-Ping Liu Zhong-Yong Yuan 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第2期259-267,共9页
The exploration of cost-effective non-noble-metal electrocatalysts is highly imperative to replace the state-of-the-art platinum-based catalysts for oxygen reduction reaction(ORR). Here, we prepared cobalt phosphonate... The exploration of cost-effective non-noble-metal electrocatalysts is highly imperative to replace the state-of-the-art platinum-based catalysts for oxygen reduction reaction(ORR). Here, we prepared cobalt phosphonate-derived N-doped cobalt phosphate/carbon nanotube hybrids(Co Pi C-N/CNTs) by hydrothermal treatment of N-containing cobalt phosphonate and oxidized carbon nanotubes(o-CNT) followed by high-temperature calcination under nitrogen atmosphere. The resultant Co Pi C-N/CNT exhibits a superior electrocatalytic performance for the ORR in alkaline media, which is equal to the commercial Pt/C catalyst in the aspect of half-wave potential, onset potential and diffuse limiting current density. Furthermore, the excellent tolerance to methanol and strong durability outperform those of commercial Pt/C. It is found that cobalt phosphonate-derived N-doped cobalt phosphate and the in-situ formed graphitic carbons play key roles on the activity enhancement. Besides, introducing a suitable amount of CNTs enhances the electronic conductivity and further contributes to the improved ORR performance. 展开更多
关键词 Metal phosphonate Metal phosphate Carbon nanotubes Oxygen reduction reaction ELECTROCATALYSIS
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Effects of Potassium and Manganese Promoters on Nitrogen-Doped Carbon Nanotube-Supported Iron Catalysts for CO_2 Hydrogenation 被引量:6
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作者 Praewpilin Kangvansura Ly May Chew +6 位作者 Chanapa Kongmark Phatchada Santawaja Holger Ruland Wei Xia Hans Schulz Attera Worayingyong Martin Muhler 《Engineering》 SCIE EI 2017年第3期385-392,共8页
Nitrogen-doped carbon nanotubes (NCNTs) were used as a support for iron (Fe) nanoparticles applied in car- bon dioxide (CO_2) hydrogenation at 633 K and 25 bar (1 bar = 10-5 Pa). The Fe/NCNT catalyst promoted ... Nitrogen-doped carbon nanotubes (NCNTs) were used as a support for iron (Fe) nanoparticles applied in car- bon dioxide (CO_2) hydrogenation at 633 K and 25 bar (1 bar = 10-5 Pa). The Fe/NCNT catalyst promoted with both potassium (K) and manganese (Mn) showed high performance in CO_2 hydrogenation, reaching 34.9% conversion with a gas hourly space velocity (GHSV) of 3.1 L-(g·h)-1. Product selectivities were high for olefin products and low for short-chain alkanes for the K-promoted catalysts. When Fe/NCNT catalyst was promot- ed with both K and Mn, the catalytic activity was stable for 60 h of reaction time. The structural effect of the Mn promoter was demonstrated by X-ray diffraction (XRD), temperature-programmed reduction (TPR) with molecular hydrogen (H2), and in situ X-ray absorption near-edge structure (XANES) analysis. The Mn pro- moter stabilized wtistite (FeO) as an intermediate and lowered the TPR onset temperature. Catalytic ammo- nia (NH_3) decomposition was used as an additional probe reaction for characterizing the promoter effects. The Fe/NCNT catalyst promoted with both K and Mn had the highest catalytic activity, and the Mn-promoted Fe/NCNT catalysts had the highest thermal stability under reducing conditions. 展开更多
关键词 CO_2 hydrogenation Iron catalyst Nitrogen-doped carbon nanotubes Manganese promoter Potassium promoter
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ACEI attenuates the progression of CCl_4-induced rat hepatic fibrogenesis by inhibiting TGF-β1, PDGF-BB, NF-κB and MMP-2,9 被引量:12
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作者 Xu Li Ying Meng +2 位作者 Xi-Shan Yang Ling-Fei Mi Shao-Xi Cai 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第31期4807-4811,共5页
AIM: Angiotensin II has pro-fibrotic function in the liver. Blockade of the renin-angiotensin-aldosterone-system (RAAS) attenuates hepatic fibrosis. The aim of the present study was to determine the mechanism of an... AIM: Angiotensin II has pro-fibrotic function in the liver. Blockade of the renin-angiotensin-aldosterone-system (RAAS) attenuates hepatic fibrosis. The aim of the present study was to determine the mechanism of angiotensin-converting enzyme inhibitor (ACEI) on the progression of rat hepatic fibrosis. METHODS: Forty male Wistar rats were divided into three groups. Model group (Mo): The rats were injected subcutaneously with 40% of CCl4 0.25 mL/100 g. Perindopril group (Pe): The rats were injected subcutaneously with 40% of CCl4. Perindopril, equivalent to 2 mg/(kg·d), was administrated. Control group (Nc): the rats were treated with olive oil only. After 4 and 6 wk, the rats were killed. The liver sections were stained with Masson. The protein expressions of ATIR, TGF-β1 and PDGF-BB were examined by Western blot. Nuclear factor κB (NF-κB) DNA binding activity was examined by EMSA (Electrophoretic gel mobility shift assay). Matrix metalloproteinase-2,9 (MMP-2,9) activity was assessed by zymography. Serum laminin (LN) and hyaluronic acid (HA) were measured using radioimmunoassays. RESULTS: Using Western blot, we clearly provided direct evidence for the expression of ATIR in liver. The expression was up-regulated when fibrogenesis occurred. Perindopril treatment significantly reduced mean fibrosis score, protein levels of ATIR, TGF-β1 and PDGF-BB, serum levels of HA and LN, and the activity of MMP-2,9. NF-κB DNA bindingactivity markedly increased in model group, perindopril treatment considerably reduced NF-κB DNA binding activity.CONCLUSION: Perindopril attenuates CCl4-induced hepatic fibrogenesis of rat by inhibiting TGF-β1, PDGF-BB, NF-BB and MMP-2,9. 展开更多
关键词 Renin-angiotensin-aldosterone system Angiotensin-converting enzyme inhibitor Hepatic fibrosis
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Food Additives-Ascorbic Acid Quality Assay Test Intelligent Management 被引量:1
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作者 Hairui Zhang Li Zhang +1 位作者 Helin Ye Guofu Zhang 《Journal of Chemistry and Chemical Engineering》 2018年第1期20-25,共6页
In this paper, based on the analysis and test methods of national standards (GB 14754-2010) and chemical analysis and test items carried out by chemical enterprises, a set of automatic processing of quality analysis... In this paper, based on the analysis and test methods of national standards (GB 14754-2010) and chemical analysis and test items carried out by chemical enterprises, a set of automatic processing of quality analysis test data of ascorbic acid products was developed by using access database technology and Visual Basic programming language system, and its stability was investigated. The results show that the software can manage intelligently all aspects of the quality analysis and test of ascorbic acid products, uploading timely the data and results of the analysis and inspection to the network and saving it for users, enterprises and quality management, which set up a network of information sharing platform to ensure the authenticity and reliability of measurement results, improving greatly the speed of data processing, saving valuable time, reducing production costs with good economic efficiency and social benefit. It has practical value for ascorbic acid quality analysis test data processing automatically the results of the implementation of intelligent management. 展开更多
关键词 Food additive ascorbic acid quality analysis test intelligent management software development.
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Preparation and photocatalytic activity of Gd-doped TiO_2 nanofibre 被引量:2
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作者 周艺 张世英 +1 位作者 朱志平 李永坤 《Journal of Central South University of Technology》 EI 2005年第6期657-661,共5页
In order to realize the photocatalysis of TiO2 in the sunlight and directly apply it to waste water treatment, the Gd-doped TiO2 nanofibre was synthesized using two-step synthesis method as follows: Firstly, potassium... In order to realize the photocatalysis of TiO2 in the sunlight and directly apply it to waste water treatment, the Gd-doped TiO2 nanofibre was synthesized using two-step synthesis method as follows: Firstly, potassium carbonate, titanium dioxide and proper gadolinium oxide (dopant) were calcined in the muffle at high temperature and the doped gadolinium K2Ti4O9 fibres were obtained; secondly, the fibre was heated using glycerol as solvent until Gd-doped TiO2 nanofibres were obtained. The synthesized samples were characterized using scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The results show that Gd-doped TiO2 nanofibre heat-treated by glycerol solvent can inhibit the agglomeration, so the grain diameter of the fibre is smaller than that without heat-treated with glycerol. Meanwhile, the diameter of the fibre decreases with the increase of the heating temperature and time. 97% 98% of Gd-doped TiO2 nanofibre is anatase. The photocatalysis results showed that the photocatalysis activity of Gd-doped TiO2 nanofibre is just a little lower than that of TiO2 powder. 展开更多
关键词 photocatalytic activity two-step synthesis method Gd-doped TiO2 nanofibre K2Ti4O9 photocatalytic degradation
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