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Laparoscopy-assisted gastrectomy for advanced gastric cancer patients with situs inversus totalis: Two case reports and review of literature 被引量:1
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作者 hong-bo liu Xiao-Peng Cai +2 位作者 Zhao Lu Bin Xiong Chun-Wei Peng 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第9期2063-2073,共11页
BACKGROUND Situs inversus totalis(SIT)is a rare condition in which the positions of abdominal and thoracic organs present a“mirror image”of the normal ones in the median sagittal plane.Although minimally invasive su... BACKGROUND Situs inversus totalis(SIT)is a rare condition in which the positions of abdominal and thoracic organs present a“mirror image”of the normal ones in the median sagittal plane.Although minimally invasive surgery has evolved to achieve laparoscopic gastrectomy for gastric cancer(GC)patients with SIT,it is difficult to perform lymphadenectomy(LND)in such a transposed anatomical condition.Herein,we report the cases of two patients with SIT who successfully underwent laparoscopy-assisted gastrectomy(LAG)with D2 LND.CASE SUMMARY Case 1:A 65-year-old man was admitted for intermittent abdominal pain and distension,occasional belching,and acid reflux for 4 mo.He was diagnosed with GC(cT3N1-2M0)with SIT.Before surgery,he had undergone four cycles of neoadjuvant chemotherapy and immunotherapy.Then,the patient was evaluated as having a partial response,and laparoscopy-assisted distal gastrectomy with D2 LND and Billroth II reconstruction were performed.The operation was performed successfully within 240 min with an estimated blood loss of 50 mL and no severe complications.The patient was discharged on postoperative day(POD)9.Case 2:A 55-year-old man was admitted for upper abdominal distension with pain and discomfort after eating for 3 mo.He was diagnosed with GC(cT3N1M0)with SIT.He had a history of hypertension for more than 10 years;however,his blood pressure was well-controlled via regular medication.We performed laparoscopy-assisted total gastrectomy with D2 LND and Roux-en-Y reconstruction.The operation was performed successfully within 168 min with an estimated blood loss of 50 mL and no severe complications.The patient was discharged on POD 10.CONCLUSION LAG with D2 LND could be considered an accessible,safe,and curative procedure for advanced GC patients with SIT. 展开更多
关键词 Situs inversus totalis Laparoscopy-assisted gastrectomy Advanced gastric cancer Surgery modality LYMPHADENECTOMY Case report
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Left epigastric isolated tumor fed by the inferior phrenic artery diagnosed as ectopic hepatocellular carcinoma:A case report
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作者 hong-bo liu Li-Hua Zhao +3 位作者 Yong-Jian Zhang Zhi-Feng Li Lei Li Qian-Peng Huang 《World Journal of Clinical Cases》 SCIE 2023年第26期6231-6239,共9页
BACKGROUND Hepatocellular carcinoma(HCC)is one of the most frequent cancers and the main cause of cancer-related death worldwide.Ectopic HCC,an extremely rare type of HCC,exhibits a wide range of clinical signs and ra... BACKGROUND Hepatocellular carcinoma(HCC)is one of the most frequent cancers and the main cause of cancer-related death worldwide.Ectopic HCC,an extremely rare type of HCC,exhibits a wide range of clinical signs and radiographic features,making preoperative identification challenging.CASE SUMMARY A 47-year-old man underwent routine abdominal color ultrasonography,which identified an asymptomatic tumor in the left upper abdomen.The patient had no history of hepatitis,did not drink alcohol,and had no family history of cancer.Abdominal contrast-enhanced computed tomography(CT)revealed a heterogeneously enhanced lesion between the spleen and stomach that had invaded the diaphragm,with blood supplied by the left inferior phrenic artery.The patient underwent laparoscopic surgery,and HCC was identified by postoperative pathology.Additionally,specific immunohistochemical staining was performed to assess the molecular biological characteristics of the HCC.The patient underwent two rounds of hepatic arterial interventional chemotherapy after surgery.Abdominal plain and enhanced magnetic resonance imaging and lung CT 3 mo postoperatively revealed no signs of local recurrence or distant metastasis.CONCLUSION This asymptomatic ectopic HCC case described achieved an excellent result due to early detection,radical resection,and systematic surveillance. 展开更多
关键词 Ectopic hepatocellular carcinoma Left subphrenic tumor Isolated tumor Diaphragmatic involvement Inferior phrenic artery Case report
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MicroRNA-122-5p、microRNA-33a-3p在胃癌患者中的表达及与临床病理特征和预后的关系 被引量:4
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作者 张伟 蔡振花 +5 位作者 周瑞轻 刘小慧 江麒麟 刘红波 董永杰 冯运章 《中国现代医学杂志》 CAS 北大核心 2021年第13期17-22,共6页
目的探究胃癌患者血清microRNA-122-5p(miR-122-5p)、microRNA-133a-3p(miR-133a-3p)mRNA相对表达量与临床病理特征及预后的关系。方法采集胃癌患者血清标本94例,以相同例数的健康体检者的血清样本作为对照。采用实时荧光定量聚合酶链反... 目的探究胃癌患者血清microRNA-122-5p(miR-122-5p)、microRNA-133a-3p(miR-133a-3p)mRNA相对表达量与临床病理特征及预后的关系。方法采集胃癌患者血清标本94例,以相同例数的健康体检者的血清样本作为对照。采用实时荧光定量聚合酶链反应(qRT-qPCR)技术检测血清miR-122-5p、miR-133a-3p mRNA相对表达量,同时分析两者与胃癌患者临床病理特征的关系;绘制Kaplan-Meier生存曲线,分析miR-122-5p、miR-133a-3p的表达与胃癌患者预后的关系。结果胃癌患者血清miR-122-5p、miR-133a-3p mRNA相对表达量低于健康体检者(P<0.05);有淋巴结转移、分化程度低、浸润至浆膜层的患者血清miR-122-5p mRNA相对表达量低于无淋巴结转移,中、高分化程度、浸润至黏膜下各层的患者(P<0.05);有淋巴结转移、低分化程度、浸润至浆膜层、TNM分期为Ⅲ+Ⅳ期的患者血清miR-133a-3p mRNA相对表达量低于无淋巴结转移,中、高分化程度,浸润至黏膜下各层,TNM分期为Ⅰ+Ⅱ期的患者(P<0.05);Kaplan-Meier生存曲线结果显示,miR-122-5p低表达胃癌患者5年生存率低于miR-122-5p高表达胃癌患者(P<0.05);miR-133a-3p低表达胃癌患者的5年生存率低于miR-133a-3p高表达胃癌患者(P<0.05)。结论胃癌患者血清miR-122-5p、miR-133a-3p mRNA相对表达量呈低表达,并且两者与胃癌的恶性程度和患者不良预后密切相关,血清miR-122-5p、miR-133a-3p可能成为胃癌患者预后预测的潜在生物标志物。 展开更多
关键词 胃肿瘤 microRNA-122-5p microRNA-133a-3p 临床病理特征 预后
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Regulation of demethylation and re-expression of RASSF1A gene in gastric cancer cell lines by combined treatment of 5-Aza-CdR and NaB 被引量:21
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作者 Wen-Jing Shen Dong-Qiu Dai +1 位作者 Yue Teng hong-bo liu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第4期595-600,共6页
AIM: To investigate the changes of methylation state and expression of RASSF1A gene in human gastric cancer cell lines SGC7901 and BGC823 which were treated in vitro with demethlylating agent 5-Aza-CdR in combination... AIM: To investigate the changes of methylation state and expression of RASSF1A gene in human gastric cancer cell lines SGC7901 and BGC823 which were treated in vitro with demethlylating agent 5-Aza-CdR in combination with histone deacetylase inhibitor NaB. METHODS: After SGC7901 and BGC823 cells were treated with 5-Aza-CdR and/or NaB, the methylation state of RASSFIA gene was detected by methylationspecific PCR, and the changes in expression of mRNA and protein level of RASSFIA gene were observed by RT-PCR and Western-blotting before and after drug treatment. RESULTS: Hypermethylation was detected in the promoter region of RASSF1A gene in both SGC7901 and BGC823 cells, and there was no expression of this gene at both mRNA and protein level. After treatment with 5-Aza-CdR, demethylation occurred in the promoter region of RASSFIA gene, which subsequently induced re-expression of this gene. The treatment with NaB alone showed no effect on the methylation state and expression of RASSFIA gene. The combined treatment of 5-Aza-CdR and NaB induced complete demethylation of RASSFIA gene, leading to a significantly higher reexpression of the mRNA and protein of RASSFIA than those treated with 5-Aza-CdR alone (P 〈 0.05). CONCLUSION: Hypermethylation in the promoter region is related to inactivation of RASSFIA gene in human gastric cancer cell lines SGC7901 and BGC823, while demethlylating agent 5-Aza-CdR can reverse the methylation state of RASSF1A gene and induce itsre-expression. Histone deacetylase inhibitor NaB had a synergistic effect with 5-Aza-CdR in both demethylation and gene transcriptional regulation. 展开更多
关键词 5-AZA-CDR NAB RASSFIA gene Gastric cancer DNA methylation
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Performance of common imaging techniques vs serum biomarkers in assessing fibrosis in patients with chronic hepatitis B: A systematic review and meta-analysis 被引量:14
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作者 Xue-Ying Xu Wu-Sheng Wang +4 位作者 Qi-Meng Zhang Jun-Ling Li Jin-Bin Sun Tian-Tian Qin hong-bo liu 《World Journal of Clinical Cases》 SCIE 2019年第15期2022-2037,共16页
BACKGROUND Noninvasive biomarkers have been developed to predict hepatitis B virus(HBV)related fibrosis owing to the significant limitations of liver biopsy.Both serum biomarkers and imaging techniques have shown prom... BACKGROUND Noninvasive biomarkers have been developed to predict hepatitis B virus(HBV)related fibrosis owing to the significant limitations of liver biopsy.Both serum biomarkers and imaging techniques have shown promising results and may improve the evaluation of liver fibrosis.However,most of the previous studies focused on the diagnostic effects of various imaging techniques on fibrosis in all chronic liver diseases.AIM To compare the performance of common imaging methods and serum biomarkers for prediction of significant fibrosis caused only by HBV infection.METHODS A systematic review was conducted on the records available in PubMed,EMBASE,and the Cochrane Library electronic databases until December 2018.We systematically assessed the effectiveness of two serum biomarkers and three imagine techniques in predicting significant fibrosis solely caused by HBV infection.The serum biomarkers included aspartate aminotransferase-to-platelet ratio index(APRI)and fibrosis index based on the 4 factors(FIB-4).The three imaging techniques included acoustic radiation force impulse(ARFI),FibroScan,and magnetic resonance elastography(MRE).Three parameters,the area under the summary receiver operating characteristic curve(AUSROC),the summary diagnostic odds ratio,and the summary sensitivity and specificity,were used to examine the accuracy of all tests for liver fibrosis.RESULTS Out of 2831 articles evaluated for eligibility,204 satisfied the predetermined inclusion criteria for this current meta-analysis.Eventually,our final data contained 81 studies.The AUSROCs of serum biomarkers of APRI and FIB-4 were both 0.75.For imaging techniques(ARFI,FibroScan,and MRE),the areas were 0.89,0.83,and 0.97,respectively.The heterogeneities of ARFI and FibroScan were statistically significant(I2>50%).The publication bias was not observed in any of the serum biomarkers or imaging methods.CONCLUSION These five methods have attained an acceptable level of diagnostic accuracy.Imaging techniques,MRE in particular,demonstrate significant advantages in accurately predicting HBV-related significant fibrosis,while serum biomarkers are admissible methods. 展开更多
关键词 HEPATITIS B VIRUS DIAGNOSTIC test Imaging technology Liver FIBROSIS Metaanalysis
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Geology and mineralization of the Sanshandao supergiant gold deposit(1200 t)in the Jiaodong Peninsula,China:A review 被引量:15
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作者 Ming-chun Song Zheng-jiang Ding +13 位作者 Jun-jin Zhang Ying-xin Song Jun-wei Bo Yu-qun Wang hong-bo liu Shi-yong Li Jie Li Rui-xiang Li in Wang Xiang-dong liu Liang-liang Zhang Lei-lei Dong Jian Li Chun-yan He 《China Geology》 2021年第4期686-719,共34页
The Jiaodong Peninsula in Shandong Province,China is the world’s third-largest gold metallogenic area,with cumulative proven gold resources exceeding 5000 t.Over the past few years,breakthroughs have been made in dee... The Jiaodong Peninsula in Shandong Province,China is the world’s third-largest gold metallogenic area,with cumulative proven gold resources exceeding 5000 t.Over the past few years,breakthroughs have been made in deep prospecting at a depth of 500‒2000 m,particularly in the Sanshandao area where a huge deep gold orebody was identified.Based on previous studies and the latest prospecting progress achieved by the project team of this study,the following results are summarized.(1)3D geological modeling results based on deep drilling core data reveal that the Sanshandao gold orefield,which was previously considered to consist of several independent deposits,is a supergiant deposit with gold resources of more than 1200 t(including 470 t under the sea area).The length of the major orebody is nearly 8 km,with a greatest depth of 2312 m below sea level and a maximum length of more than 3 km along their dip direction.(2)Thick gold orebodies in the Sanshandao gold deposit mainly occur in the specific sections of the ore-controlling fault where the fault plane changes from steeply to gently inclined,forming a stepped metallogenic model from shallow to deep level.The reason for this strong structural control on mineralization forms is that when ore-forming fluids migrated along faults,the pressure of fluids greatly fluctuated in fault sections where the fault dip angle changed.Since the solubility of gold in the ore-forming fluid is sensitive to fluid pressure,these sections along the fault plane serve as the target areas for deep prospecting.(3)Thermal uplifting-extensional structures provide thermodynamic conditions,migration pathways,and deposition spaces for gold mineralization.Meanwhile,the changes in mantle properties induced the transformation of the geochemical properties of the lower crust and magmatic rocks.This further led to the reactivation of ore-forming elements,which provided rich materials for gold mineralization.(4)It can be concluded from previous research results that the gold mineralization in the Jiaodong gold deposits occurred at about 120 Ma,which was superimposed by nonferrous metals mineralization at 118‒111 Ma.The fluids were dominated by primary mantle water or magmatic water.Metamorphic water occurred in the early stage of the gold mineralization,while the fluid composition was dominated by meteoric water in the late stage.The S,Pb,and Sr isotopic compositions of the ores are similar to those of ore-hosting rocks,indicating that the ore-forming materials mainly derive from crustal materials,with the minor addition of mantle-derived materials.The gold deposits in the Jiaodong Peninsula were formed in an extensional tectonic environment during the transformation of the physical and chemical properties of the lithospheric mantle,which is different from typical orogenic gold deposits.Thus,it is proposed that they are named“Jiaodong-type”gold deposits. 展开更多
关键词 Gold deposit Deep prospecting Thermal uplifting-extension mineralization Transformation of mantle properties Stepped metallogenic model Mineral exploration engineering Jiaodong-type gold deposits Sanshandao Jiaodong Peninsula China
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Geochemical records of the sediments and their significance in Dongping Lake Area,the lower reach of Yellow River,North China 被引量:4
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作者 Lin-song Yu hong-bo liu +3 位作者 Fang Wan Zun-fang Hu Huai-dong Luo Xiu-wen Zhang 《Journal of Groundwater Science and Engineering》 2021年第2期140-151,共12页
Dongping Lake area,located in the lower reaches of Yellow River,is an ideal place to study the changes of modern river and lake sedimentary environment.The sediment samples of Dawen River,Yellow River,and Dongping Lak... Dongping Lake area,located in the lower reaches of Yellow River,is an ideal place to study the changes of modern river and lake sedimentary environment.The sediment samples of Dawen River,Yellow River,and Dongping Lake were collected,and the major elements,trace elements and organic matter geochemical composition of the samples were analyzed.Cluster analysis,characteristic element ratio method and graphic method were used to explore the geochemical characteristics of sediments and their environmental implication.The results show that the contents of SiO_(2),Na_(2)O,TiO_(2) and Zr in sediments of Dawen River and Yellow River are relatively high,and the contents of iron and manganese oxides,organic matter,CaO,P2O5 and Sr in lake sediments are relatively high.That reveals the differences of sedimentary environments between the rivers and the lake.The contents of Sr and Zr in Dawen River are affected by the rapid migration of clastic materials in the upstream carbonate source area during the flood season;the δCe,ΣREE and REE’s ratios in the sediments of the Yellow River reflect the influence of the Loess source;and the distribution of elements changes along the flow direction during the flood season.The characteristics of pH,element composition and LREE&HREE fractionation of the lake sediments indicate that the sediment source is complex,and the lake environment is affected by the flood season.The study shows that the geochemical content and its variation characteristics of sediments effectively reveal the sedimentary environment,material composition and characteristics of flood season of rivers and the lake in the study area. 展开更多
关键词 Dongping Lake Yellow River SEDIMENTS Organic matter Element geochemistry
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Effect of Xinjikang on left ventricular hypertrophy remodeling in hypertensive rats 被引量:1
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作者 hong-bo liu Chun-Hua Lin +2 位作者 Guang-Yu Zhou Guo-Zhen Chen Wei-Yan Cai 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2013年第12期986-989,共4页
Objective:To investigate the effects of Xinjikang on the left ventricular hypertrophy remodeling and myocardial activity in hypertension.Methods:Sixty Wistar rats were randomly divided into four groups.The pressure-lo... Objective:To investigate the effects of Xinjikang on the left ventricular hypertrophy remodeling and myocardial activity in hypertension.Methods:Sixty Wistar rats were randomly divided into four groups.The pressure-loaded left ventricular hypertrophy model was established with abdominal aorta ligation method.Rats in A and B groups were intragastrically administered with physiological saline,while C and D groups were administered with Xinjikang and metoprolol,respectively.The changes in blood pressure.E/A ratio,myocardial pathological morphology,myocardial lipoperoxides and superoxide dismustase activity in four groups were observed and compared before and after treatment.Results:There were statistically significant differences in E/A ratio between C group after treatment and model group(P<0.05).while no difference was observed between A and D groups(P>0.05);after treatment the myocardial lipoperoxides and superoxide dismustase contents in C and D groups were improved significantly compared with model group(P<0.05).Conclusions:Xinjikang can improve myocardial injury,restore myocardial parenchyma and myocardial interstitial remodeling functions in hypertensive rats with the left ventricular hypertrophy. 展开更多
关键词 HYPERTENSION RATS LEFT VENTRICULAR HYPERTROPHY Xinjikang
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Effect of Jiangu Shenjin decoction on the Wnt/β-catenin signalling pathway in knee osteoarthritis
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作者 hong-bo liu Zheng-Qing Li +4 位作者 Xi-Si Zhang Xin-Wei Pu Ri-Liang Lin Chun-Ying Jing Cai-Feng liu 《Traditional Medicine Research》 2022年第6期65-72,共8页
Background:Study the effect of Jiangu Shenjin decoction on the Wnt/β-catenin signalling pathway in knee osteoarthritis.Methods:Forty-eight female Sprague-Dawley rats were randomly divided into eight groups.After succ... Background:Study the effect of Jiangu Shenjin decoction on the Wnt/β-catenin signalling pathway in knee osteoarthritis.Methods:Forty-eight female Sprague-Dawley rats were randomly divided into eight groups.After successful modelling,the blank group and the model group were given a normal diet and drinking water,and the other rats were given meloxicam,an anti-bone hyperplasia agent and Jiangu Shenjin decoction by gavage for 4 weeks.The degree of movement and knee swelling were observed.Serum levels of interleukin-1β,interleukin-6,and tumour necrosis factor-αwere measured.The levels of inflammatory factors,pathological changes in articular cartilage and the mRNA expression levels ofβ-catenin and Wnt4 were examined.Results:Compared with the model group,the treatment group had lower levels than the model group.The medium-dose group had lower levels than the high-dose group.Compared with the meloxicam group and the anti-bone hyperplasia group,the medium-dose group had lower levels than the high-dose group.The medium-dose group had slightly lower levels than the other two groups,and the difference among the three groups was not significant.The mRNA expression level of Wnt4 andβ-catenin indicated thatβ-catenin was inhibited in the signalling pathway.The level ofβ-catenin was inhibited and then increased each treatment,and bone metabolism regulation by Jiangu Shenjin decoction was effective.Conclusion:Jiangu Shenjin decoction may act through Wnt to treat knee osteoarthritis.Theβ-catenin signalling pathway inhibits inflammatory factors and regulates proteins in the signalling pathway to affect bone metabolism. 展开更多
关键词 Jiangu Shenjin decoction Wnt/β-catenin pathway Β-CATENIN knee osteoarthritis
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The effect of selective serotonin reuptake inhibitors on cognitive function in patients with Alzheimer’s disease and vascular dementia: focusing on fluoxetine with long follow-up periods 被引量:4
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作者 Yi Xie Pei-Pei liu +2 位作者 Ya-Jun Lian hong-bo liu Jian-Sheng Kang 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2019年第1期386-388,共3页
Dear Editors,Alzheimer’s disease(AD)and vascular dementia(VaD)are two of the most common forms of dementia,resulting in increased disability and mortality,impaired quality of life,and serious burdens on society and c... Dear Editors,Alzheimer’s disease(AD)and vascular dementia(VaD)are two of the most common forms of dementia,resulting in increased disability and mortality,impaired quality of life,and serious burdens on society and caregivers.However,the presently available drugs can only alleviate symptoms for a short time without delaying the progression of the cognitive disorders.Since 2003,no new drugs have been approved by the US Food and Drug Administration for the treatment of AD.In 2019,phase III clinical trials of crenezumab and aducanumab,two anti-amyloid beta monoclonal antibodies,were terminated.The scant progress in clinical trials urges efforts towards an alternative therapeutic strategy for dementia. 展开更多
关键词 drugs ALZHEIMER IMPAIRED
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Effects of Particle Size on Nitridation Kinetics of Manganese Powder 被引量:1
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作者 Ting LUO Jian-hua liu +1 位作者 hong-bo liu Jian liu 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2015年第6期543-550,共8页
Isothermal thermo-gravimetric analysis was applied to investigate the nitridation kinetics of manganese powder with different particle sizes at 800, 900 and 1000 ℃. The apparent activation energy and nitridation kine... Isothermal thermo-gravimetric analysis was applied to investigate the nitridation kinetics of manganese powder with different particle sizes at 800, 900 and 1000 ℃. The apparent activation energy and nitridation kinetics equations of manganese powder with different particle sizes were obtained from unreacted shrinking core model and Arrhenius formula. It was found that the nitridation mechanism was controlied by interracial chemical reaction. The apparent activation energy and the apparent rate constant of nitridation reaction were affected by particle sizes. With the decrease of particle size, the apparent activation energy decreased whilst the apparent rate constant increased. It was suggested that the refinement of the manganese powder contributed to the increase of molar surface energy, which accounted for the lower apparent activation energy. 展开更多
关键词 manganese powder NITRIDATION isothermal thermo-gravimetric analysis apparent activation energy KINETICS
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Influence of Ca treatment on particle-microstructure relationship in heat-affected zone of shipbuilding steel with Zr-Ti deoxidation after high-heat-input welding 被引量:1
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作者 hong-bo liu Ju Kang +7 位作者 Xiu-juan Zhao Cai-dong Zhang Zhang-guo Lin Hong-yong Yao Zhi-qiang Tian Zhan-li liu Jie Li Chao Li 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2022年第8期1291-1298,共8页
The effects of Ca treatment on the particle, microstructure, and toughness of heat-affected zone (HAZ) of shipbuilding steel with Zr-Ti deoxidation after high-heat-input welding were investigated. The simulated weldin... The effects of Ca treatment on the particle, microstructure, and toughness of heat-affected zone (HAZ) of shipbuilding steel with Zr-Ti deoxidation after high-heat-input welding were investigated. The simulated welding at a high-heat-input welding of 200 kJ/cm was carried out using Gleeble-3800 welding simulation. Then, particle characteristics were characterized using an Aztec-Feature automatic particle analysis system. Additionally, an in-situ observation experiment was performed to study the relationships between particle and microstructure by high-temperature confocal laser scanning microscopy (HT-CLSM). The results indicated that the average HAZ toughness at -40 ℃ was increased from 183 to 290 J by adding 0.0026 wt.% Ca. Meanwhile, the formation of acicular ferrite ratio was increased from 49.34% to 60.28% due to the addition of Ca. The scanning electron microscopy results clearly showed that CaO-Al_(2)O_(3)-TiOx-ZrO_(2)-MnS particles could act as effective nucleation sites for the formation of acicular ferrite, which has been verified by the observation of the particle-microstructure relationship under HT-CLSM. Furthermore, particle characterization results show that the cumulative frequency of particles with the size of 1-3 lm was 33.2% in HAZ of Zr-Ti shipbuilding steel but 66.2% in HAZ of Zr-Ti-Ca shipbuilding steel. 展开更多
关键词 Shipbuilding steel Heat-affected zone Impact toughness MICROSTRUCTURE Particle characterization
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Parameter estimation in exponential models by linear and nonlinear fitting methods 被引量:1
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作者 Ping YANG Chao-peng WU +8 位作者 Yi-lu GUO hong-bo liu Hui HUANG Hang-zhou WANG Shu-yue ZHAN Bang-yi TAO Quan-quan MU Qiang WANG Hong SONG 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2017年第3期434-444,共11页
Estimation of unknown parameters in exponential models by linear and nonlinear fitting methods is discussed. Based on the extreme value theorem and Taylor series expansion, it is proved theoretically that the paramete... Estimation of unknown parameters in exponential models by linear and nonlinear fitting methods is discussed. Based on the extreme value theorem and Taylor series expansion, it is proved theoretically that the parameters estimated by the linear fitting method alone cannot minimize the sum of the squared residual errors in the measurement data when measurement noise is involved in the data. Numerical simulation is performed to compare the performance of the linear and nonlinear fitting methods. Simulation results show that the linear method can obtain only a suboptimal estimate of the unknown parameters and that the nonlinear method gives more accurate results. Application of the fitting methods is demonstrated where the water spectral attenuation coefficient is estimated from underwater images and imaging distances, which supports the improvement in the accuracy of parameter estimation by the nonlinear fitting method. 展开更多
关键词 Exponential model Parameter estimation Linear least squares Nonlinear fitting
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Persistent SARS-CoV-2 infection in asymptomatic young adults
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作者 Mai-Juan Ma Shao-Fu Qiu +7 位作者 Xiao-Ming Cui Ming Ni Hong-Jie liu Run-Ze Ye Lin Yao hong-bo liu Wu-Chun Cao Hong-Bin Song 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2022年第4期961-963,共3页
Dear Editor,While most of the patients infected with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)cleared the virus within a few weeks of infection,some people have a persistent infection or persistent s... Dear Editor,While most of the patients infected with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)cleared the virus within a few weeks of infection,some people have a persistent infection or persistent shedding viral RNA in the long term.The persistent detection of viral RNA in clinical specimens is unlikely to reflect either relapse or reinfection in most cases because the replication-competent virus is generally not recoverable after ten days following symptom onset in mild to moderate cases of COVID-191 and after 20 days in severe or immunocompromised cases. 展开更多
关键词 INFECTION ACUTE RESPIRATORY
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