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Red cell distribution width/platelet ratio estimates the 3-year risk of decompensation in Metabolic Dysfunction-Associated Steatotic Liver Disease-induced cirrhosis 被引量:1
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作者 Marcello Dallio Mario Romeo +8 位作者 Paolo Vaia Salvatore Auletta Simone Mammone Marina Cipullo Luigi Sapio Angela Ragone Marco Niosi Silvio Naviglio Alessandro Federico 《World Journal of Gastroenterology》 SCIE CAS 2024年第7期685-704,共20页
BACKGROUND For compensated advanced chronic liver disease(cACLD)patients,the first decompensation represents a dramatically worsening prognostic event.Based on the first decompensation event(DE),the transition to deco... BACKGROUND For compensated advanced chronic liver disease(cACLD)patients,the first decompensation represents a dramatically worsening prognostic event.Based on the first decompensation event(DE),the transition to decompensated advanced chronic liver disease(dACLD)can occur through two modalities referred to as acute decompensation(AD)and non-AD(NAD),respectively.Clinically Significant Portal Hypertension(CSPH)is considered the strongest predictor of decompensation in these patients.However,due to its invasiveness and costs,CSPH is almost never evaluated in clinical practice.Therefore,recognizing noninvasively predicting tools still have more appeal across healthcare systems.The red cell distribution width to platelet ratio(RPR)has been reported to be an indicator of hepatic fibrosis in Metabolic Dysfunction-Associated Steatotic Liver Disease(MASLD).However,its predictive role for the decompensation has never been explored.AIM In this observational study,we investigated the clinical usage of RPR in predicting DEs in MASLD-related cACLD patients.METHODS Fourty controls and 150 MASLD-cACLD patients were consecutively enrolled and followed up(FUP)semiannually for 3 years.At baseline,biochemical,clinical,and Liver Stiffness Measurement(LSM),Child-Pugh(CP),Model for End-Stage Liver Disease(MELD),aspartate aminotransferase/platelet count ratio index(APRI),Fibrosis-4(FIB-4),Albumin-Bilirubin(ALBI),ALBI-FIB-4,and RPR were collected.During FUP,DEs(timing and modaities)were recorded.CSPH was assessed at the baseline and on DE occurrence according to the available Clinical Practice Guidelines.RESULTS Of 150 MASLD-related cACLD patients,43(28.6%)progressed to dACLD at a median time of 28.9 months(29 NAD and 14 AD).Baseline RPR values were significantly higher in cACLD in comparison to controls,as well as MELD,CP,APRI,FIB-4,ALBI,ALBI-FIB-4,and LSM in dACLD-progressing compared to cACLD individuals[all P<0.0001,except for FIB-4(P:0.007)and ALBI(P:0.011)].Receiving operator curve analysis revealed RPR>0.472 and>0.894 as the best cut-offs in the prediction respectively of 3-year first DE,as well as its superiority compared to the other non-invasive tools examined.RPR(P:0.02)and the presence of baseline-CSPH(P:0.04)were significantly and independently associated with the DE.Patients presenting baseline-CSPH and RPR>0.472 showed higher risk of decompensation(P:0.0023).CONCLUSION Altogether these findings suggest the RPR as a valid and potentially applicable non-invasive tool in the prediction of timing and modalities of decompensation in MASLD-related cACLD patients. 展开更多
关键词 Liver cirrhosis Red blood cell distribution width Red blood cell distribution width to platelet ratio Translational Medicine Prognostic biomarker
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Application of neutrophil-lymphocyte ratio and red blood cell distribution width in diabetes mellitus complicated with heart failure
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作者 Jie Pang Lin-Yan Qian +1 位作者 Ping Lv Xiao-Ru Che 《World Journal of Diabetes》 SCIE 2024年第6期1226-1233,共8页
BACKGROUND Accumulating clinical evidence has shown that diabetes mellitus(DM)is a serious risk factor for cardiovascular disorders and an important factor for adverse cardiovascular events.AIM To explore the value of... BACKGROUND Accumulating clinical evidence has shown that diabetes mellitus(DM)is a serious risk factor for cardiovascular disorders and an important factor for adverse cardiovascular events.AIM To explore the value of the combined determination of the neutrophil-lymphocyte ratio(NLR)and red blood cell distribution width(RDW)in the early diagnosis and prognosis evaluation of DM complicated with heart failure(HF).METHODS We retrospectively analyzed clinical data on 65 patients with type 2 DM(T2DM)complicated with HF(research group,Res)and 60 concurrent patients with uncomplicated T2DM(control group,Con)diagnosed at Zhejiang Provincial People’s Hospital between January 2019 and December 2021.The NLR and RDW values were determined and comparatively analyzed,and their levels in T2DM+HF patients with different cardiac function grades were recorded.The receiver operating characteristic(ROC)curves were plotted to determine the NLR and RDW values(alone and in combination)for the early diagnosis of HF.The correlation between NLR and RDW with the presence or absence of cardiac events was also investigated.RESULTS Higher NLR and RDW levels were identified in the Res vs the Con groups(P<0.05).The NLR and RDW increased gradually and synchronously with the deterioration of cardiac function in the Res group,with marked differences in their levels among patients with grade II,III,and IV HF(P<0.05).ROC curve analysis revealed that NLR combined with RDW detection had an area under the curve of 0.915,a sensitivity of 76.9%,and a specificity of 100%for the early diagnosis of HF.Furthermore,HF patients with cardiac events showed higher NLR and RDW values compared with HF patients without cardiac events.CONCLUSION NLR and RDW were useful laboratory indicators for the early diagnosis of DM complicated with HF,and their joint detection was beneficial for improving diagnostic efficiency.Additionally,NLR and RDW values were directly proportional to patient outcomes. 展开更多
关键词 Neutrophil-lymphocyte ratio Red blood cell distribution width Type 2 diabetes Heart failure Early diagnosis
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R/S ratio in lead Ⅱ, and the prognostic significance of red cell distribution width in acute coronary syndrome 被引量:1
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作者 Abuzer Coskun Sevki Hakan Eren 《World Journal of Clinical Cases》 SCIE 2019年第16期2217-2226,共10页
BACKGROUND In spite of developing medical technologies to discover the etiopathogenesis of diseases and developments in the treatment of coronary artery disease, acute coronary syndromes(ACS) continue to be the main c... BACKGROUND In spite of developing medical technologies to discover the etiopathogenesis of diseases and developments in the treatment of coronary artery disease, acute coronary syndromes(ACS) continue to be the main cause of mortality and morbidity worldwide. New cardiac biomarkers and techniques are needed to help provide rapid diagnosis in order to evaluate risk in coronary artery patients.AIM To evaluate the effects of R to S ratio(RSR) in the electrocardiograph of patients with ACS, from the point of the arising complication after myocardial infarction(MI), to three-vessel disease(TVD) and mortality.METHODS The data of 1,296 patients with ACS, who presented to the emergency department of our hospital with chest pain between January 2014 and December2018 and were admitted to the cardiology clinic, were retrospectively included in this cross-sectional cohort study. Patients with an RSR value less than I were assigned to group Ⅰ, while those with an RSR value greater than Ⅰ were assigned to group Ⅱ.RESULTS In our study, 466(35.9%) of the 1,296 patients, 357(38.3%) in group 1 and 109(29.9%) in group 2, were female, with a mean age of 61.56 ± 9.42. ST-elevation MI 573(44.2%), unstable angina(UA) 502(38.7%) and non ST-elevation MI 220(17%)were more prevalent in group Ⅰ. Acute anterior MI 263(20.3) in group Ⅰ, and acute inferior MI 184(14.2) in group Ⅱ was higher. Ischemic heart failure was the most common complication. In group Ⅱ, the red cell distribution width(RDW) was 15.42 ± 1.82, the gensini score was 48.39 ± 36.44, the left ventricular ejection fraction was 41.17 ± 10.41, the TVD was 111(8.5), and the mortality rate was 72(5.6), which was significantly higher than group Ⅰ RDW; in MI with ST and nonST-elevation, in TVD, mortality and complications were high and low in UA. In single and multivariate regression analyses, the variables were associated with ACS risk.CONCLUSION RSR levels may be an auxiliary predictive value in ACS in terms of complications developing after MI, TVD, and mortality. 展开更多
关键词 Acute CORONARY SYNDROME EMERGENCY DEPARTMENT R/S ratio Red cell distribution width
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Effects of process parameters on the depth-to-width ratio of flux-cored wire underwater wet welding 被引量:3
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作者 韩焱飞 郭宁 +2 位作者 王芳 袁新 冯吉才 《China Welding》 EI CAS 2013年第1期35-40,共6页
The effects of process parameters on the depth-to-width ratio (D/W) of flux-cored wire underwater wet welding with a certain type of homemade .flux-cored wire are studied. It is found that the welding .speed, wire f... The effects of process parameters on the depth-to-width ratio (D/W) of flux-cored wire underwater wet welding with a certain type of homemade .flux-cored wire are studied. It is found that the welding .speed, wire feeding speed and torch oscillating amplitude hare significant effects on the dopth-to-width ratio (D/W) of welds. The D/W ratio of welds increases significantly with the increase of welding speed without the oscillating of welding torch. It increased (from 0. 14 to 0. 26 ) with the increase of wire feeding speed while the torch oscillating. And it decreased linearly with the increase of torch oscillating amplitude. However, the influelwe of oscillating speed, wire extension and welding voltage on the D/W ratio of welds was not obvious. 展开更多
关键词 flux-cored wire underwater wet welding depth-to-width ratio
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Change of the mode of failure by interface friction and width-to-height ratio of coal specimens 被引量:3
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作者 Gamal Rashed Syd S.Peng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第3期256-265,共10页
Bumps in coal mines have been recognized as a major hazard for many years. These sudden and violent failures around mine openings have compromised safety, ventilation and access to mine workings.Previous studies showe... Bumps in coal mines have been recognized as a major hazard for many years. These sudden and violent failures around mine openings have compromised safety, ventilation and access to mine workings.Previous studies showed that the violence of coal specimen failure depends on both the interface friction and width-to-height(W/H) ratio of coal specimen. The mode of failure for a uniaxially loaded coal specimen or a coal pillar is a combination of both shear failure along the interface and compressive failure in the coal. The shear failure along the interface triggered the compressive failure in coal. The compressive failure of a coal specimen or a coal pillar can be controlled by changing its W/H ratio. As the W/H ratio increases, the ultimate strength increases. Hence, with a proper combination of interface friction and the W/H ratio of pillar or coal specimen, the mode of failure will change from sudden violent failure which is brittle failure to non-violent failure which is ductile failure. The main objective of this paper is to determine at what W/H ratio and interface friction the mode of failure changes from violent to non-violent. In this research, coal specimens of W/H ratio ranging from 1 to 10 were uniaxially tested under two interface frictions of 0.1 and 0.25, and the results are presented and discussed. 展开更多
关键词 Bump Burst Coal strength Violent failure width-to-height(W/H) ratio Interface friction Stressestrain curve
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The Paradigm of Surgical Ellipse Dimensions: Are the Length-to-Width Ratio of 3 to 4 and a Vertex Angle of 30&ordm;Correct?
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作者 Tamara R. Tilleman M. M. Tilleman M. H. A. Neumann 《Surgical Science》 2013年第4期236-240,共5页
Background: It has been postulated that elliptical cutaneous excisions must possess a length-to-width ratio of 3 to 4 and a vertex angle of 30o or less in order to be closed primarily without creating a “dog ear”. T... Background: It has been postulated that elliptical cutaneous excisions must possess a length-to-width ratio of 3 to 4 and a vertex angle of 30o or less in order to be closed primarily without creating a “dog ear”. These dimensions became axiomatic in cutaneous surgery and have been taught in the apprenticeship model for years. The present article examines the validity of that paradigm. Methods: We collected data from two sources: ellipses described in the literature (57 cases);and elliptical excisions performed at the authors’ outpatient clinic (83 cases). The surgical ellipse lengths, widths, and vertex angles were analyzed, and the data were compared to a mathematical formula used to generate a fusiform ellipse. Results: The length-to-width ratio of 3 - 4 was found to be inconsistent with the recommended vertex angle of 30o. In fact, a length-to-width ratio of 3 - 4 determines a vertex angle of 48o - 63o. A 30o vertex angle is only feasible with long length-to-width ration of about 7.5. Conclusions: The paradigm that surgical ellipses should have a vertex angle of 30o with length-to-width ratio of 3 - 4 is incorrect. Evidence from actual surgical practice and from mathematical formulation shows that either the length-to-width ratio must be larger than 3 - 4 or the vertex angle must be larger than 30 degrees. 展开更多
关键词 Elliptical EXCISION Length-to-width ratio of 3 - 4 30o Vertex Angle
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The Value of MLPR,NLR,and RDW in the Assessment of Combined Pulmonary Embolism in Elderly Patients with AECOPD
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作者 Ya Zhang Jianye Yang 《Journal of Clinical and Nursing Research》 2024年第7期255-260,共6页
Objective:To investigate the diagnostic value of the monocyte-to-large-platelet ratio(MLPR),neutrophil-to-lymphocyte ratio(NLR),and red blood cell distribution width(RDW)for pulmonary embolism(PE)in patients with acut... Objective:To investigate the diagnostic value of the monocyte-to-large-platelet ratio(MLPR),neutrophil-to-lymphocyte ratio(NLR),and red blood cell distribution width(RDW)for pulmonary embolism(PE)in patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD).Methods:A total of 60 elderly AECOPD patients were enrolled and divided into embolus group(12 cases)and thrombus group(48 cases)according to whether they were combined with pulmonary embolism and the MLPR,NLR,and RDW values of the two groups were determined respectively.Results:The patients in the two groups had different degrees of vascular structural and functional abnormalities,and the MLPR,NLR,and RDW in the embolus group were significantly higher than those in the thrombus group(P<0.05);while the differences in NLR and RDW between the two groups were not significant.Conclusion:MLPR,NLR,and RDW can provide an objective basis for assessing PE in elderly AECOPD patients. 展开更多
关键词 Monocyte-to-large-platelet ratio(MLPR) Neutrophil-to-lymphocyte ratio(NLR) Red blood cell distribution width(RDW) Acute exacerbation of chronic obstructive pulmonary disease(AECOPD) Pulmonary embolism
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Effects of Lobe Peak-to-Trough Width Ratio on Mixing and Combustion Performance in ATR Combustors
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作者 ZHAO Qingjun ZHANG Yuankun +3 位作者 HU Bin WANG Zhonghao SHI Qiang ZHAO Wei 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2022年第6期637-650,共14页
The air-turbo-rocket(ATR)engine is a promising propulsion plant for achieving numerous surface and air launched missile missions.The application of lobed mixer in the ATR combustor can promote the mixing of the fuelri... The air-turbo-rocket(ATR)engine is a promising propulsion plant for achieving numerous surface and air launched missile missions.The application of lobed mixer in the ATR combustor can promote the mixing of the fuelrich gas and the air,thus improving the engine performance significantly.The numerical simulation method was conducted to explore the effects of lobe peak-to-trough width ratio on mixing and combustion performance in ATR combustors.Results show that:For a given peak lobe width b1,the combustion efficiency and total pressure loss decrease with the increase of trough lobe width b2;For a given b2,the combustion efficiency and total pressure loss decrease with the increase of b1;The fan-type lobed mixer with smaller b2has a better effect on promoting the combustion efficiency in the region near the ATR combustor center line than that with a pair of parallel side walls.The total pressure recovery coefficient reaches more than 0.99 at the exit of combustor in nonreactive combustion while the total pressure loss reaches more than 4%in the reacting combustion.Compared with the mixing process,more than80%of the total pressure loss is caused during combustion. 展开更多
关键词 ATR combustor lobed mixer lobe peak-to-trough width ratio MIXING combustion streamwise vortex
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Theoretic expression of flow rate for a single fracture with linearly varying width
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作者 Haonan Liang Weiqun Liu 《Theoretical & Applied Mechanics Letters》 2012年第5期43-45,共3页
By means of reasonable assumption and mathematical derivation, a theoretic expression of flow rate for a single fracture with linearly varying width was obtained. The mathematical derivation was based on the cubic law... By means of reasonable assumption and mathematical derivation, a theoretic expression of flow rate for a single fracture with linearly varying width was obtained. The mathematical derivation was based on the cubic law and the new theoretic expression was an extention of traditional parallel plate model. This study may help to analyze seepage in fractured rock mass. 展开更多
关键词 flow rate cubic law single fracture with linearly varying width
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The relationship of blood cell-associated inflammatory indices and diabetic retinopathy: a Meta-analysis and systematic review 被引量:10
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作者 Wen-Juan Luo Wen-Fang Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第2期312-323,共12页
AIM: To explore the correlation between several blood cell-associated inflammatory indices including mean platelet volume(MPV), platelet distribution width(PDW), neutrophil to lymphocyte ratio(NLR) and platelet-lympho... AIM: To explore the correlation between several blood cell-associated inflammatory indices including mean platelet volume(MPV), platelet distribution width(PDW), neutrophil to lymphocyte ratio(NLR) and platelet-lymphocyte ratio(PLR), and the presence and severity of diabetic retinopathy(DR). METHODS: We searched for eligible studies from PubMed, EMBASE, Web of Science and CNKI up to December 13, 2017. Standardized mean difference(SMD) calculated with confidence interval(CI) of 95% was used to estimate the values of those indices. RESULTS: A total of 31 studies were included in the present Meta-analysis. As compared with type 2 diabetes mellitus(T2 DM) patients without DR, the values of MPV, PDW, NLR, and PLR were higher in patients with DR(SMD=0.67; 95%CI: 0.36 to 0.98; SMD=0.51; 95%CI: 0.27 to 0.75; SMD=0.77; 95%CI: 0.49 to 1.05 and SMD=1.18; 95%CI: 0.07 to 2.28). Additionally, it was also observed that MPV was closely correlated with the severity of DR. CONCLUSION: MPV, PDW, NLR, and PLR could be recommended as diagnostic biomarkers for DR, and MPV could be applied to assess the severity of DR. 展开更多
关键词 mean PLATELET volume PLATELET distribution width NEUTROPHIL to LYMPHOCYTE ratio platelet-lymphocyte ratio diabetic RETINOPATHY
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Development of the active flux in superalloy laser welding and the effect on the weld formation 被引量:3
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作者 Chen Yuhua Liu Dongya +1 位作者 Xie Jilin Yue Zuzhen 《China Welding》 EI CAS 2017年第1期44-48,共5页
In this study,adopting uniform design method established a mathematical model to prepare multi-element active flux. GH4169 superalloy plates were welded by the Nd: YAG laser equipment with the prepared active flux. Th... In this study,adopting uniform design method established a mathematical model to prepare multi-element active flux. GH4169 superalloy plates were welded by the Nd: YAG laser equipment with the prepared active flux. The results show all kinds of fluxes increase the depth to width ratio and the multi-component systems are more significant. The largest increment of the weld depth to width ratio is 159%,obtained by using of the F12 series flux. It is proved that by using of the active flux to increase the depth to width ratio of micro laser welding is feasible. 展开更多
关键词 micro-laser welding DEVELOPMENT of active FLUXES uniform design method depth to width ratio
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Crack elongation and its width of large depth reinforced concrete beams 被引量:2
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作者 管俊峰 赵顺波 黄承逵 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第5期631-635,共5页
In order to meet the requirement of structural inspection,the crack spacing and crack width at various heights in the tensile zone of six large depth reinforced concrete beams were measured under several loading level... In order to meet the requirement of structural inspection,the crack spacing and crack width at various heights in the tensile zone of six large depth reinforced concrete beams were measured under several loading levels of serviceability state.The effects of the depth of normal section beams on the crack spacing and crack width were analyzed,and the modified model is proposed for calculating the average crack spacing by thinking about the depth of normal section,the reinforcement arrangement and the effective reinforcement ratio.The relationships of crack widths at any position in the tensile zone and at the reinforcement level on the side surface of beam were studied.By theoretical and statistical analysis,a method is proposed to calculate the ratios of crack widths between any position and the reinforcement level on the side surface of large depth reinforced concrete beams. 展开更多
关键词 reinforced concrete beam large depth of normal section crack elongation average crack spacing ratio of crack width
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Prognostic value of a nomogram model for postoperative liver metastasis of colon cancer
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作者 De-Xin Cheng Kang-Di Xu +1 位作者 Han-Bo Liu Yi Liu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第4期1055-1065,共11页
BACKGROUND Colon cancer is one of the most common malignant tumors of the digestive system.Liver metastasis after colon cancer surgery is the primary cause of death in patients with colon cancer.AIM To construct a nov... BACKGROUND Colon cancer is one of the most common malignant tumors of the digestive system.Liver metastasis after colon cancer surgery is the primary cause of death in patients with colon cancer.AIM To construct a novel nomogram model including various factors to predict liver metastasis after colon cancer surgery.METHODS We retrospectively analyzed 242 patients with colon cancer who were admitted and underwent radical resection for colon cancer in Zhejiang Provincial People’s Hospital from December 2019 to December 2022.Patients were divided into liver metastasis and non-liver metastasis groups.Sex,age,and other general and clinicopathological data(preoperative blood routine and biochemical test indexes)were compared.The risk factors for liver metastasis were analyzed using singlefactor and multifactorial logistic regression.A predictive model was then constructed and evaluated for efficacy.RESULTS Systemic inflammatory index(SII),C-reactive protein/albumin ratio(CAR),red blood cell distribution width(RDW),alanine aminotransferase,preoperative carcinoembryonic antigen level,and lymphatic metastasis were different between groups(P<0.05).SII,CAR,and RDW were risk factors for liver metastasis after colon cancer surgery(P<0.05).The area under the curve was 0.93 for the column-line diagram prediction model constructed based on these risk factors to distinguish whether liver metastasis occurred postoperatively.The actual curve of the column-line diagram predicting the risk of postoperative liver metastasis was close to the ideal curve,with good agreement.The prediction model curves in the decision curve analysis showed higher net benefits for a larger threshold range than those in extreme cases,indicating that the model is safer.CONCLUSION Liver metastases after colorectal cancer surgery could be well predicted by a nomogram based on the SII,CAR,and RDW. 展开更多
关键词 Systemic immunoinflammatory index C-reactive protein/albumin ratio Erythrocyte distribution width Colon cancer Liver metastasis Novel nomogram model
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Experimental Study on Chloride Ion Penetration Resistance of Coal Gangue Concrete under Multi-Factor Comprehensive Action 被引量:1
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作者 Hongyu Chen Hongguang Zhu +1 位作者 Hongqiang Ma Mingyue Zhang 《World Journal of Engineering and Technology》 2019年第2期58-64,共7页
In order to investigate the chloride ion penetration resistance of coal gangue concrete under multi-factor comprehensive action, the non-steady-state accelerated chloride ion migration test was used to test the chlori... In order to investigate the chloride ion penetration resistance of coal gangue concrete under multi-factor comprehensive action, the non-steady-state accelerated chloride ion migration test was used to test the chloride diffusion law of coal gangue concrete specimens by crack width, curing temperature and water-cement ratio. Three groups of crack width (0 mm, 0.05 - 0.12 mm, 0.12 - 0.2 mm), three curing temperatures (high temperature 45, medium temperature 25, low temperature 10), three water cement ratios (0.3, 0.4, 0.5) were set in the experiment. The results show that when the curing temperature and water cement ratio are constant, the crack width less than 0.12 mm has little effect on the chloride content and chloride diffusion coefficient. When the crack width is larger than 0.12 mm, the chloride penetration depth increases with the crack width. The resistance to chloride ion penetration of gangue concrete is greatly influenced by the water cement ratio. The influ-ence degree of three factors on chloride ion migration coefficient of gangue concrete is as follows: water cement ratio > crack width > curing temperature. 展开更多
关键词 Coal GANGUE Concrete CHLORIDE Ion PENETratioN Water CEMENT ratio Crack width CURING Temperature
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Experimental study on the seismic behavior of high strength concrete fi lled double-tube columns 被引量:14
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作者 Qian Jiaru Li Ningbo +1 位作者 Ji Xiaodong Zhao Zuozhou 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2014年第1期47-57,共11页
To study the seismic behavior of high strength concrete fi lled double-tube(CFDT) columns,each consisting of an external square steel tube and an internal circular steel tube,quasi-static tests on eight CFDT column sp... To study the seismic behavior of high strength concrete fi lled double-tube(CFDT) columns,each consisting of an external square steel tube and an internal circular steel tube,quasi-static tests on eight CFDT column specimens were conducted.The test variables included the width-to-thickness ratio(β1) and the area ratio(β2) of the square steel tube,the wall thickness of the circular steel tube,and the axial force(or the axial force ratio) applied to the CFDT columns.The test results indicate that for CFDT columns with a square steel tube with β1 of 50.1 and 24.5,local buckling of the specimen was found at a drift ratio of 1/150 and 1/50,respectively.The lateral force-displacement hysteretic loops of all specimens were plump and stable.Reducing the width-to-thickness ratio of the square steel tube,increasing its area ratio,or increasing the wall thickness of the internal circular steel tube,led to an increased fl exural strength and deformation capacity of the specimens.Increasing the design value of the axial force ratio from 0.8 to 1.0 may increase the fl exural strength of the specimens,while it may also decrease the ultimate deformation capacity of the specimen with β1 of 50.1. 展开更多
关键词 high strength concrete fi lled double-tube(CFDT)column seismic behavior area ratio of the square steel tube width-to-thickness ratio of the square steel tube axial force ratio quasi-static test
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Effect of Peak Power and Pulse Width on Coherent Doppler Wind Lidar’s SNR 被引量:4
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作者 REN Yong WU Xuefei +1 位作者 TAO Fa CAO Haishuai 《Instrumentation》 2022年第2期26-32,共7页
The laser device is the core component of coherent Doppler wind lidar.The peak power and pulse width of laser transmitting pulse have important effects on SNR.Based on coherent Doppler wind pulse lidar,the peak power ... The laser device is the core component of coherent Doppler wind lidar.The peak power and pulse width of laser transmitting pulse have important effects on SNR.Based on coherent Doppler wind pulse lidar,the peak power and pulse width influence on SNR is studied on the theoretical derivation and analysis,and the results show that the higher the peak power can realize the greater the signal-to-noise ratio of coherent Doppler wind lidar.But when the peak power is too large,the laser pulse may appear nonlinear phenomenon,which cause the damage of the laser.So,the peak power must be less than the stimulated brillouin scattering power threshold.Increasing the pulse width can make the laser device to output more energy,but it will also make the spatial resolution lower,and the influence of turbulence on SNR will be greater.After a series of simulation analyses,it can be concluded that when the peak power is 650W and the pulse width is 340ns,the SNR of the system can be maximized.In addition,the coherent Doppler wind lidar system is set up to carry out corresponding experimental verification.The experimental results are consistent with the theoretical analysis and simulation,which verifies the correctness of the theoretical analysis and simulation results.It provides theoretical basis and practical ex-perience for the design of laser transmitting pulse in coherent Doppler wind lidar system. 展开更多
关键词 Coherent Lidar Fiber Laser Peak Power Pulse width Signal-to-Noise ratio(SNR)
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Theoretical analyses on bed topography responses in large depth-to-width ratio river bends with constant curvatures 被引量:2
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作者 Shuxian GAO Haijue XU Yuchuan BAI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2018年第5期747-766,共20页
Bed morphology is the result of a dynamic response to a complex meandering river system. It is an important factor for the further development of river. Based on the meandering river characterized by a large depth-to-... Bed morphology is the result of a dynamic response to a complex meandering river system. It is an important factor for the further development of river. Based on the meandering river characterized by a large depth-to-width ratio, a theoretical model is established with the coupling of Navier-Stokes (N-S)~ sediment transport, and bed deformation equations. The flow characteristics and bed response of river are obtained with the perturbation method. The research results show that, under the effect of two- dimensional flow disturbance, the bars and pools present the regular response. For a given sinuousness, the amplitude of the bed response can be used as a criterion to judge the bedform stability. The effects of the Reynolds number, disturbance wavenumber, sinuousness, and bed morphology gradient on the bed response development are described. 展开更多
关键词 meandering river large depth-to-width ratio channel disturbance wave bed response
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THE INFLUENCE OF LOW-FREQUENCY VARYING MAGNETIC FIELDON THE PULSATILE FLOW IN A RIGID ROUND TUBE
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作者 孙东宁 吴望一 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第2期121-127,共7页
In this paper, the analytic solution of the dynamical equation of the pulsatile flow in a rigid round tube under the low-frequency varying magnetic field is obtained. The velocity distribution and the flow impedance a... In this paper, the analytic solution of the dynamical equation of the pulsatile flow in a rigid round tube under the low-frequency varying magnetic field is obtained. The velocity distribution and the flow impedance are calculated. The results of e valuable for understanding the influence of low-frequency varying magnetic field on hemodynamics and its clinical application. 展开更多
关键词 low-frequency varying magnetic field pulsatile flow IMPEDANCE impedance ratio
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qSOFA评分联合红细胞分布宽度与血钙比值对重症急性胰腺炎的早期识别及Nomogram图的构建
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作者 郭旻晞 朱炳喜 《医学研究杂志》 2024年第6期146-150,共5页
目的探讨快速序贯器官衰竭评分(quick sequential organ failure assessment,qSOFA)联合红细胞分布宽度与血钙比值(red blood cell distribution width-to-serum calcium ratio,RDC)对重症急性胰腺炎(severe acute pancreatitis,SAP)的... 目的探讨快速序贯器官衰竭评分(quick sequential organ failure assessment,qSOFA)联合红细胞分布宽度与血钙比值(red blood cell distribution width-to-serum calcium ratio,RDC)对重症急性胰腺炎(severe acute pancreatitis,SAP)的预测价值。方法回顾性分析2018年6月~2022年10月徐州医科大学附属医院收治的319例急性胰腺炎患者的临床资料,根据病情严重程度分为非SAP组(n=260)和SAP组(n=59)。所有患者均于入院24h内进行血样采集并检测相应血液学指标,并于24h内进行qSOFA与急性胰腺严重床旁指数(bedside index for severity in acute pancreatitis,BISAP)评分。比较两组间的临床资料并进行Logistic回归分析危险因素。采用受试者工作特征(receiver operating characteristic,ROC)曲线评估qSOFA评分、RDC及两者联合评分对SAP的预测效能,并与BISAP评分进行比较。结果多因素Logistic回归分析发现,RDC(OR=4.111,95%CI:2.053~8.231,P<0.05)和qSOFA(OR=9.732,95%CI:3.974~23.832,P<0.05)高评分是SAP的独立危险因素。联合评分及BISAP评分预测SAP的曲线下面积(area under the curve,AUC)分别为0.915(95%CI:0.872~0.959,P<0.001)、0.839(95%CI:0.782~0.896,P<0.001),敏感度分别为93.2%、66.1%,特异性分别为85.0%、86.2%。结论qSOFA评分、RDC均可预测SAP的发生,两者联合评分对SAP发生的预测效能更高,可用于早期识别SAP的发生并指导早期干预。 展开更多
关键词 重症急性胰腺炎 快速序贯器官衰竭评分 红细胞分布宽度与血钙比值 列线图 早期识别
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Determination Multipole Mixing Ratios and Transition Strengths of Gamma Rays from Level Studies of 93Mo (p, nγ) Reaction
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作者 Mayyada M. Hamarashid 《Journal of Physical Science and Application》 2012年第7期253-257,共5页
The multipole mixing ratios have been calculated by a2-ratio method, from levels of 93Mo(p, nγ) reaction. The branching ratios of such γ-transitions are used to calculate the total gamma widths. Besides, the trans... The multipole mixing ratios have been calculated by a2-ratio method, from levels of 93Mo(p, nγ) reaction. The branching ratios of such γ-transitions are used to calculate the total gamma widths. Besides, the transition strengths and probabilities have been calculated for γ-transitions from excited states whose life times have been reported previously. The results are found to be in general in good agreement with the previous results populated from the previous work. 展开更多
关键词 Moltipole mixing ratio mean lifetime gamma widths transitions strength transitions probabilities.
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