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Correlation between Waist Circumference and Carotid Intima-Media Thickness in Women from Shanghai, China 被引量:4
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作者 SHEN Yun ZHANG Lei +7 位作者 ZONG Wen Hong WANG Zheng ZHANG Yin YANG Man Jing MA Xiao Jing ZHU Jia An BAO YuQian JIA Wei Ping 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第7期531-538,共8页
Objective To evaluate whether waist circumference (WC) 〉85 cm is related to asymptomatic preclinical atherosclerosis in women from Shanghai, China. Methods A total of 2365 females aged 〉20 years recruited from 4 c... Objective To evaluate whether waist circumference (WC) 〉85 cm is related to asymptomatic preclinical atherosclerosis in women from Shanghai, China. Methods A total of 2365 females aged 〉20 years recruited from 4 communities underwent physical examination and carotid artery scanning. Their carotid intima-media thickness (C-iMT) was measured. Results The C-IMT was significantly higher in overweight or obese women with their BMI 〉25.0 kg/m2 {P〈O.01) and in those with their WC _〉85 cm than in those with their WC 〈85 cm (P〈O.01). Spearman and partial correlation analysis showed that the C-IMT was significantly correlated with WC which was independent of menopausal status. The C-IMT significantly increased with the increasing WC and reached to a platform in about 85 cm. An increment tendency was found in the subgroup with its WC 〈 85 cm (P〈O.01) while no significant tendency was found in the subgroup with its WC_〉85 cm (P=0.07). Multiple stepwise regression analysis showed that the WC was an independent risk factor for C-IMT. In logistic regression model, the odd ratio of WC _〉80 cm, _〉80 cm and 〈85 cm and 〉85 cm for evaluating the risk of C-IMT elevation was 2.632, 2.501, and 1.878, respectively. Conclusion WC is significantly correlated with C-IMT in women from Shanghai, China, and WC_〉85 cm may be used in identifying the risk of subclinical carotid atherosclerosis. 展开更多
关键词 Visceral obesity Waist circumference Carotid intima-media thickness
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Ultrasound Assessraent of Intima-media Thickness and Diameter of Carotid Arteries in Patients Undergoing Hemodialysis or Renal Transplantation 被引量:1
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作者 Zhao-jun Li Lian-fang DU +2 位作者 Yan QIN Ji-bin LIU Xiang-hong LUO 《Current Medical Science》 SCIE CAS 2018年第4期727-733,共7页
Renal transplant (RT) recipients have a high risk of developing cardiovascular diseases. However, the effects of renal transplantation on the development of arteriosclerosis have been controversial. The carotid inti... Renal transplant (RT) recipients have a high risk of developing cardiovascular diseases. However, the effects of renal transplantation on the development of arteriosclerosis have been controversial. The carotid intima-media thickness (CIMT) and diameter (CD) are important indicators of vascular remodeling and arteriosclerosis. In this study, 31 patients with hemodialysis (HD), 31 RT recipients and 84 age- and gender-matched control subjects were enrolled. Their CIMT and CD were measured by ultrasonic radiofrequency tracking, and the linear regression models and Z test were used to identify the progression of arteriosclerosis and the risk factors. Compared with HD group, RT group had significantly lower CIMT and CD. CIMT was found to be associated with age, body weight, resistance index and diastolic velocity, while CD was associated significantly with age, body weight, pulsatility index, end diastolic velocity and diastolic blood pressure (DBP), respectively. The correlation curves between CIMT and age showed the slopes of curves were decreased successively in control, RT and HD groups, and the curves between CD and age showed the slopes were decreased in order of RT 〉 control 〉 HD groups. It was concluded that CIMT and CD were significantly correlated with age in RT and moderately with age in HD patients. RT could reduce the progress of arteriosclerosis in patients with end-stage renal disease. 展开更多
关键词 ultrasonic radiofrequency tracking renal transplantation ARTERIOSCLEROSIS carotid intima-media thickness age
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Relationship between Carotid Intima-Media Thickness and Diabetes Clinical Risk Factors among Normotensive Type 2 Diabetes Mellitus among Native Black African Population 被引量:1
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作者 Ekwutosi Anthony Okafor Ademola Joseph Adekanmi Omolola Mojisola Atalabi 《International Journal of Clinical Medicine》 2018年第3期203-219,共17页
Background: Type 2 diabetes mellitus is frequently associated with atherosclerosis with changes in the thickness of the intima-media of carotid arteries which causes increased risk of cardiovascular diseases. Cardiova... Background: Type 2 diabetes mellitus is frequently associated with atherosclerosis with changes in the thickness of the intima-media of carotid arteries which causes increased risk of cardiovascular diseases. Cardiovascular disease is a major cause of morbidity and mortality in this group of patients. The carotid artery reflects the degree of atherosclerosis in the various vessels especially coronary arteries. Measurement of the carotid artery thickness with real time, relatively cheap and non-invasive ultrasonography method is used in monitoring atherosclerotic disease progression and response to treatment. This study is aimed at ultrasonographic evaluation of the carotid intima-media thickness (CIMT) in adult Type 2 Diabetic patients compared to non-diabetic healthy controls matched for age, gender and body mass index (BMI). And to also determine its association if any with selected clinical factors among a native Black African population. Methodology: This was a prospective case control study involving 54 adult type 2 diabetics and 54 adult non-diabetic controls. CIMT was measured at 3 segments of the extracranial carotid arteries by a 7.5 - 10 MHz linear transducer of a portable Mindray M5 ultrasound machine. Results: Among the native black African population studied, there was significant difference in CIMT of adult type 2 diabetics compared to healthy non-diabetics adults (p value = 0.012 and 0.001 on the right and left respectively). The mean carotid intima-media thickness in diabetics was 0.81 mm and 0.85 mm, while in non-diabetics it was 0.74 mm and 0.75 mm on the right and left respectively. The presence of diabetes showed independent positive correlation with CIMT (beta: 0.24, p value = 0.004). Age (beta: 0.30, p value = 0.001) and plasma cholesterol level (beta: 0.30, p value = 0.013) also had positive correlation with CIMT. Conclusion: There was statistically significant difference in carotid intima-media thickness between adult type 2 diabetics and age, sex matched non-diabetics. DM showed independent correlation with CIMT. 展开更多
关键词 Type 2 DIABETES MELLITUS CAROTID intima-media thickness Atherosclerosis
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A REVIEW ON ARTERY WALL SEGMENTATION TECHNIQUES AND INTIMA-MEDIA THICKNESS MEASUREMENT FOR CAROTID ULTRASOUND IMAGES
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作者 XIN YANG WANJI HE +4 位作者 KAITONG LI JIAOYING JIN XUMING ZHANG MING YUCHI MINGYUE DING 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2012年第1期75-84,共10页
Stroke and heart attack,which could be led by a kind of cerebrovascular and cardiovascular disease named as atherosclerosis,would seriously cause human morbidity and mortality.It is important for the early stage diagn... Stroke and heart attack,which could be led by a kind of cerebrovascular and cardiovascular disease named as atherosclerosis,would seriously cause human morbidity and mortality.It is important for the early stage diagnosis and monitoring medical intervention of the atherosclerosis.Carotid stenosis is a classical atherosclerotic lesion with vessel wall narrowing down and accumulating plaques burden.The carotid artery of intima-media thickness(IMT)is a key indicator to the disease.With the development of computer assisted diagnosis technology,the imaging techniques,segmentation algorithms,measurement methods,and evaluation tools have made considerable progress.Ultrasound imaging,being real-time,economic,reliable,and safe,now seems to become a standard in vascular assessment methodology especially for the measurement of IMT.This review firstly attempts to discuss the clinical relevance of measurements in clinical practice at first,and then followed by the challenges that one has to face when approaching the segmentation of ultrasound images.Secondly,the commonly used methods for the IMT segmentation and measurement are presented.Thirdly,discussion and evaluation of different segmentation techniques are performed.An overview of summary and future perspectives is given finally. 展开更多
关键词 Ultrasound(US)images carotid artery intima-media thickness(IMT) ATHEROSCLEROSIS image segmentation computer assisted diagnosis(CAD)
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Determining factors for carotid mean/max intima-media thickness and brachial flow-mediated dilation in healthy young women
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作者 Shiro Hoshida Takashi Miki +2 位作者 Takafumi Nakagawa Yukinori Shinoda Takayoshi Adachi 《World Journal of Cardiovascular Diseases》 2012年第2期43-49,共7页
Background: Many factors can contribute to atherosclerotic-type vascular changes in older individuals or men. Thus, confining the investigation to young women with no clinical evidence of the condition could enhance u... Background: Many factors can contribute to atherosclerotic-type vascular changes in older individuals or men. Thus, confining the investigation to young women with no clinical evidence of the condition could enhance understanding of the early stages of cardiovascular disease. The aim of this study was to determine whether carotid mean/max intima-media thickness (IMT) and brachial flow-mediated dilation (FMD) values, which are well-known event-related indices, are associated with laboratory data and the other vascular indices of atherosclerosis in healthy young women. Methods: Carotid mean/max IMT and brachial FMD were measured in young women with no clinical evidence of atherosclerosis (n = 110;mean age, 39 years) who were instructed not to eat, drink or smoke after 9 PM the evening before testing. All participants also underwent laboratory assessment, including simultaneous measurements of arterial stiffness such as augmentation index (AI), cardioankle vascular index (CAVI) and brachial-ankle pulse wave velocity (baPWV). Results: Mean IMT was signifi-cantly and positively associated with age (p = 0.002), CAVI (p = 0.044), low-density lipoprotein-cholesterol (LDL-C, p = 0.047) and high-sensitive C-reactive protein (hs-CRP, p = 0.002) values but was not related to FMD, AI, baPWV or triglycerides (TG) in the multivariate regression analysis. Similarly, max IMT was positively associated with age (p p = 0.003) and hs-CRP (p = 0.005) values but was not related to FMD, AI, CAVI, baPWV, TG or blood pressure level in the multivariate regression analysis. The association between LDL-C and max IMT was much stronger than that between LDL-C and mean IMT. Brachial FMD was positively associated only with heart rate in the multivariate regression analysis. Conclusions: These results suggest that mean IMT more closely represents the sclerotic aspect of vascular change, whereas max IMT represents the atherotic aspect in healthy young women. Although the relationship between the autonomic nervous system and heart rate is well-known, there may be a complex interaction between the autonomic nervous system and endothelial function. 展开更多
关键词 intima-media thickness Flow-Mediated DILATION YOUNG Women
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Relationship between peripheral arterial disease, carotid intima-media thickness and C-reactive protein in elderly diabetic patients
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作者 Moatassem Salah Amer Samia Ahmed Abdul-Rahman +3 位作者 Wafaa Mostafa Abd-El Gawad Ibrahim Ahmad Abdel Aal Ahmad Abdel Khalek Abdel Razek Mohamed Wessam El-Huseiny Moustafa Abdel Wahab 《Advances in Aging Research》 2013年第4期115-120,共6页
Purpose: To study the association between carotid intima media thickness (CIMT) and high sensitivity CRP (hs-CRP) level as markers for PAD in elderly patients with DM. Subjects: A case-control study on 90 participants... Purpose: To study the association between carotid intima media thickness (CIMT) and high sensitivity CRP (hs-CRP) level as markers for PAD in elderly patients with DM. Subjects: A case-control study on 90 participants aged 60 years and older divided into 60 cases (30 patients with DM alone and 30 patients with DM and comorbidities) and 30 healthy controls. All were assessed by measuring CIMT, ankle brachial index (AB), and markers for cardiovascular disease such as high-sensitivity CRP (hs-CRP), total cholesterol (TC), triglycerides (TG), high density lipoprotein (HDL), and low density lipoprotein (LDL). Results: hs-CRP levels showed statistically significant difference being highest among patients with DM and comorbidities and lowest among controls (P < 0.001). Also, symptoms of PAD were significantly higher among cases than controls. ABI was able to detect PAD in many asymptomatic patients. Color changes were present in only 43.30% (n = 26) of positive PAD cases while delayed wound healing, claudication pain, rest pain, cold extremities, and trophic changes were present in 23.30% (n = 14), 16.71% (n = 10), 16.71% (n = 10), 45.00% (n = 27), and 21.7% (n = 13). Using logistic regression analysis revealed that DM, CIMT, and hs-CRP were independent predictors for PAD (OR = 4.194, 7.236, 1.003;P value = 0.044, 0.25, 0.031) after adjustment of other coronary risk factors such as sex, smoking, hypertension, TC, and TG. Conclusion: Diabetic elderly have higher prevalence of asymptomatic PAD thannon-diabetics using solely ABI. DM, CIMT, and hs-CRP are independent predictors for the occurrence of PAD. Hs-CRP levels are highest among diabetics with comorbidities. 展开更多
关键词 PERIPHERAL ARTERIAL Disease CAROTID intima-media thickness ANKLE BRACHIAL Index C-Reactive Protein Elderly
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Relationship of plasma homocysteine, soluble intercellular adhesion molecule-1, high mobility group box 1 protein with carotid intima-media thickness in elderly patients with type 2 diabetes mellitus
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作者 Zhijie Cai Jun Xue +4 位作者 Xiaohui Ma Peifeng Chen Biao Ge Yuying Zhang Zhihui Dong 《Discussion of Clinical Cases》 2022年第1期9-12,共4页
Objective:To explore the relationship of plasma homocysteine(Hcy),soluble intercellular adhesion molecule-1(sICAM-1)and high mobility group box 1 protein(HMGB1)with carotid intima-media thickness(c-IMT)in elderly pati... Objective:To explore the relationship of plasma homocysteine(Hcy),soluble intercellular adhesion molecule-1(sICAM-1)and high mobility group box 1 protein(HMGB1)with carotid intima-media thickness(c-IMT)in elderly patients with type 2 diabetes mellitus.Methods:A total of 100 elderly patients who were diagnosed as type 2 diabetes mellitus in Baogang Hospital of Inner Mongolia from June 2017 to May 2020 were chosen as research objects.According to c-IMT,they were divided into the normal group(n=35),the mild to moderate group(n=41)and the severe group(n=24).The expression levels of plasma Hcy,sICAM-1 and HMGB1 were compared between groups respectively.Pearson’s correlation coefficient was used to analyze the relationship of plasma Hcy,sICAM-1,HMGB1 with c-IMT.Results:The comparison in plasma Hcy,sICAM-1,HMGB1 and c-IMT among the three groups of patients was of statistical significance(p<.05).The results of correlation analysis showed that the expression levels of plasma Hcy,sICAM-1 and HMGB1 were positively correlated with c-IMT in elderly patients with type 2 diabetes mellitus(r=.627,.598,.614;p<.05).Conclusions:The expression levels of plasma Hcy,sICAM-1 and HMGB1 are abnormally increased in elderly patients with type 2 diabetes mellitus,and related to c-IMT,which can provide a strong evidence for clinical diagnosis and treatment by detecting their levels in clinical practice. 展开更多
关键词 Type 2 diabetes mellitus Carotid intima-media thickness HOMOCYSTEINE Soluble intercellular adhesion molecule-1 High mobility group box 1 protein
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Measurement of Cortical Bone Thickness in Adults by Cone-beam Computerized Tomography for Orthodontic Miniscrews Placement 被引量:3
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作者 赵弘 顾晓明 +2 位作者 刘洪臣 王照五 寻春雷 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2013年第2期303-308,共6页
The purpose of this study was to investigate the cortical bone thickness of the inter-dental area of both jaws for orthodontic miniscrew placement. The cone-beam computerized tomography images of 32 non-orthodontic ad... The purpose of this study was to investigate the cortical bone thickness of the inter-dental area of both jaws for orthodontic miniscrew placement. The cone-beam computerized tomography images of 32 non-orthodontic adults with normal occlusion were taken to measure the cortical bone thick- ness in both.jaws. One-way analysis of variance (ANOVA) was used to analyze the differences in cortical bone thickness. Buccal cortical bone in the mandible was thicker than that in the maxilla. In the maxilla, cortical bone thickness was thicker in the buccal side than in the palatal side. Buccal cortical bone thickness in the mandible was thickest at the site distal to the first molar, and in the maxilla it was thickest at the site mesial to the first molar, while in the palatal side of maxilla it was thickest at the site mesial to the second premolar. The changing pattern of cortical bone thickness varies at different sites. In the buccal side of maxilla, the thinnest cortical bone thickness was lbund to be at 4 mm level from the alveolar crest, while the thickest was at 10 mm level (except for the site mesial to the first premolar). The buccal cortical bone thickness at the sites mesial or distal to the first molar in the mandible and palatal cortical bone thickness of maxilla tended to increase with increasing distance from the alveolar bone. 展开更多
关键词 MINISCREW cortical bone thickness bone quality
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QTL Mapping for Hull Thickness and Related Traits in Hybrid Rice Xieyou 9308
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作者 LUO Li-li ZHANG Ying-xin +4 位作者 CHEN Dai-bo ZHAN Xiao-deng SHEN Xi-hong CHENG Shi-hua CAO Li-yong 《Rice science》 SCIE 2014年第1期29-38,共10页
We conducted a quantitative trait locus (QTL) analysis of 165 rice recombinant inbred lines derived from a cross between Zhonghui 9308 (Z9308) and Xieqingzao B (XB) in Hainan and Hangzhou, China. Grain thickness... We conducted a quantitative trait locus (QTL) analysis of 165 rice recombinant inbred lines derived from a cross between Zhonghui 9308 (Z9308) and Xieqingzao B (XB) in Hainan and Hangzhou, China. Grain thickness (GT), brown rice thickness (BRT), hull thickness (HT) and milling quality were used for QTL mapping. HT was significantly and positively correlated with GT and BRT. Twenty-nine QTLs were detected with phenotypic effects ranging from 2.80% to 21.27%. Six QTLs, qGT3, qBRT3, qBRT4, qHT6.1, qHT8 and qHT11, were detected repeatedly across two environments. Inherited from XB qHT6.1, qHT8 and qHT11 showed stable expression, explaining 9.92%, 21.27% and 10.83% of the phenotypic variances in Hainan and 9.61%, 6.40% and 6.71% in Hangzhou, respectively. Additionally, the QTL cluster between RM5944 and RM5626 on chromosome 3 was probably responsible for GT and milling quality. The cluster between RM6992 and RM6473 on chromosome 4 played an important role in grain filling. Three near isogenic lines (NILs), X345, X338 and X389, were selected because they contained homozygous fragments from Zhonghui 9308, corresponding to qHT6.1, qHT8 and qHT11, respectively. The hull of XB was thicker than those of X345, X338 and X389. In all the lines, qHT6.1, qHT8 and qHT11 that regulated rice HT were stably inherited with obvious genetic effects. 展开更多
关键词 RICE hull thickness milling quality QTI_ mapping
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VARIATIONS IN CRUSTAL THICKNESS OF THE KANE TRANSFORM IN THE NORTH ATLANTIC OCEAN
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作者 Philip D.Rabinowitz 胡延昌 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2001年第4期350-360,共11页
A new approach was taken to investigate the crustal stucture of the Kane transform and its aseismic extension, using high quality bathymetry and gravity data. The gravity signatures associated with variations in crust... A new approach was taken to investigate the crustal stucture of the Kane transform and its aseismic extension, using high quality bathymetry and gravity data. The gravity signatures associated with variations in crustal thickness of the transform were isolated from the observed free air anomaly, was continued downward to the mean depth of the crust/mantle interface and converted onto the relief on that surface. The crustal thickness of the transform was then calculated by subtracting seawater depth from the depth of the gravity inferred crust/mantle interface.3 D gravity investigation results indicate that the Kane transform and adjacent areas are associated with a crust thinner than normal oceanic crust. The transform trough is largely underlain by a crust less than 4.5km thick and in the nodal basins the crust may be as thin as 3 km. The crust beneath the fracture zone valley is 4-5.5 km thick. The rift valleys on the spreading segments are also characterized by thin crust (4-5 km thick). Thin oceanic crust extends to 20-30 km from the transform axis,except for some localized places such as the inside corner highs adjoining the ridge transform intersections. These gravity inferred results match fairly well with limited published seismic results. Thinning of the crust is mainly attributable to a thin layer 3, which in turn may be explained by the combined effects of reduced magma supply at the ends of the spreading segments and tectonic activities in the region. 展开更多
关键词 测深学 地心引力 地壳厚度 北大西洋
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Correlation Study of Aortic Velocity Propagation, Abdominal Aortic Intima-Media Thickness, and Epicardial Adipose Tissue Thickness in Subclinical Hypothyroidism Patients
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作者 Juan Luo Jiaqi Chen +2 位作者 Yueyi Li Jingfeng Li Nengwen Lin 《Journal of Clinical and Nursing Research》 2024年第8期153-158,共6页
Objective:To explore the correlation between epicardial fat thickness(EFT),aortic velocity propagation(AVP),and abdominal aortic intima-media thickness(AA-IMT)in patients with subclinical hypothyroidism(SH).Additional... Objective:To explore the correlation between epicardial fat thickness(EFT),aortic velocity propagation(AVP),and abdominal aortic intima-media thickness(AA-IMT)in patients with subclinical hypothyroidism(SH).Additionally,to compare these indicators between SH patients and healthy individuals,providing a new theoretical basis for the clinical prevention and treatment of cardiovascular diseases.Method:Clinical data from 50 SH patients(23 males and 27 females)and 50 healthy outpatient examinees(22 males and 28 females)were analyzed.The participants were selected from January 2022 to December 2023 at Loudi Central Hospital.EFT,AVP,and AA-IMT were measured,and their correlations were analyzed.Results:SH patients had significantly higher EFT and AA-IMT levels than the control group,while their AVP was significantly lower,with these differences being statistically significant(P<0.05).Correlation analysis revealed a significant negative correlation between EFT and AVP(P<0.001),a significant positive correlation between EFT and AAO-IMT(P<0.001),and a significant negative correlation between AVP and AAO-IMT(P<0.001).Multivariate binary logistic regression analysis identified increased EFT,decreased AVP,and increased AAO-IMT as independent risk factors for SH patients.Conclusion:In SH patients,EFT and AAO-IMT are elevated,whereas AVP is reduced.EFT and AVP are significantly correlated with AAO-IMT.EFT and AAO-IMT can serve as reliable indicators for evaluating subclinical atherosclerosis in SH patients,providing a diagnostic basis for clinical practice. 展开更多
关键词 Epicardial fat thickness Aortic propagation velocity Abdominal aortic intima-media thickness Subclinical hypothyroidism
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压缩感知不同加速因子对心脏磁共振电影序列成像质量的影响
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作者 王林林 贺克武 +5 位作者 赵韧 俞宏林 孙若愚 钱银锋 李小虎 余永强 《中国医学影像学杂志》 CSCD 北大核心 2024年第6期581-586,共6页
目的 探讨不同加速因子的压缩感知(CS)技术对心脏磁共振电影序列图像质量的影响及临床应用的可行性。资料与方法 前瞻性招募合肥市第一人民医院2021年1—7月40名健康志愿者进行心脏磁共振成像,扫描方案共4组(采用SENSE 2及加速因子分别... 目的 探讨不同加速因子的压缩感知(CS)技术对心脏磁共振电影序列图像质量的影响及临床应用的可行性。资料与方法 前瞻性招募合肥市第一人民医院2021年1—7月40名健康志愿者进行心脏磁共振成像,扫描方案共4组(采用SENSE 2及加速因子分别为3、4、8的CS心脏电影序列),每组成像方案包括四腔心、左心室短轴、左心室两腔心及三腔心序列,对比4种方案的图像质量主观评分、左心室心功能及16节段心肌厚度。结果 以SENSE 2图像为标准评分(5分),CS3、CS4评分均在3分以上,CS8评分均在3分及以下,其中CS3与SENSE 2序列的四腔心及左心室短轴图像质量主观评分差异无统计学意义(P均>0.05);左心室两腔心及三腔心各序列组图像质量主观评分差异均有统计学意义(P均<0.05)。4种成像方案的左心室心功能(左心室射血分数、左心室收缩末期容积、左心室舒张末期容积、左心室每搏输出量、左心室舒张末期心肌质量)(F=0.027、0.182、0.057、0.140、0.545)与心肌厚度(F=0.052~7.366)各组间差异均无统计学意义(P均>0.05)。结论 基于CS技术的心脏电影序列具有良好的应用前景。随着加速因子的增加,扫描时间逐渐减少,相应的图像质量降低,而当加速因子为4(与常规电影序列相比扫描时间减少50%)时,仍能够准确进行左心室心功能及心肌厚度测量,且图像质量基本满足诊断需求。 展开更多
关键词 心脏磁共振 压缩感知技术 图像质量评估 心室功能 心肌厚度
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重载列车荷载作用下路基夹层现象的分析
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作者 丁瑜 贾羽 +2 位作者 王晅 宗钟凌 张家生 《中山大学学报(自然科学版)(中英文)》 CAS CSCD 北大核心 2024年第2期59-66,共8页
重载列车荷载作用下路基夹层、道砟囊、翻浆冒泥等路基病害频发,严重影响了列车的安全运行。为分析重载列车荷载作用下路基夹层现象,采用自制试样筒对路基土(粉质黏土)和道砟进行循环加载试验,分析重载列车荷载作用下试样变形特性及路... 重载列车荷载作用下路基夹层、道砟囊、翻浆冒泥等路基病害频发,严重影响了列车的安全运行。为分析重载列车荷载作用下路基夹层现象,采用自制试样筒对路基土(粉质黏土)和道砟进行循环加载试验,分析重载列车荷载作用下试样变形特性及路基夹层的产生与发展过程;进而提出路基夹层的两个主要表征指标,即路基夹层厚度和细颗粒迁移质量。结果表明:1)重载列车荷载作用下,试样的轴向变形呈非线性增大的趋势;路基夹层在加载初期较为明显,加载后期路基夹层的变化不明显。2)采用路基夹层厚度及细颗粒迁移质量这两个指标对路基夹层特性进行表征,路基夹层厚度、细颗粒迁移质量与路基土体初始干密度近似呈线性负相关关系,与循环荷载幅值近似呈线性正相关关系,而加载频率对路基夹层厚度和细颗粒迁移质量的影响相对较小。 展开更多
关键词 重载列车 路基夹层 轴向变形 路基夹层厚度 细颗粒迁移质量
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超厚料层烧结水碳结构优化研究
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作者 戴玉山 胡文祥 +3 位作者 王义惠 周文波 王耀祖 李思达 《冶金能源》 北大核心 2024年第2期3-6,14,共5页
为保证料层厚度由600 mm提高至1000 mm后,烧结生产稳定顺行,通过烧结杯实验,研究了料层厚度及水碳结构对料层透气性和烧结矿质量的影响。优化后烧结产能及质量得到改善,垂烧速度、转鼓指数和整体利用系数由15.2 mm/min、65.0%和1.23 t/(... 为保证料层厚度由600 mm提高至1000 mm后,烧结生产稳定顺行,通过烧结杯实验,研究了料层厚度及水碳结构对料层透气性和烧结矿质量的影响。优化后烧结产能及质量得到改善,垂烧速度、转鼓指数和整体利用系数由15.2 mm/min、65.0%和1.23 t/(m^(2)·h)提高至22.3 mm/min、68.9%和1.54 t/(m^(2)·h)。确认了现场烧结原料结构下的最佳配水量为7.5%,同时不降低固体燃料用量,为超厚料层烧结稳定生产提供了数据指导。 展开更多
关键词 铁矿石烧结 水碳结构 厚料层烧结 烧结矿质量
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宽厚板结晶器电磁搅拌的设计与运用
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作者 韦如军 《武汉工程职业技术学院学报》 2024年第2期6-10,27,共6页
由于宽厚板对结晶器稳定性的高要求,原有结晶器电磁搅拌技术已难以满足生产宽厚板的要求。为此在宽厚板上采用分段式铁芯磁路设计能增强结晶器水箱的强度和使用稳定性要求。通过数值模拟的方法,对宽厚板铁芯分段式结晶器电磁搅拌的磁路... 由于宽厚板对结晶器稳定性的高要求,原有结晶器电磁搅拌技术已难以满足生产宽厚板的要求。为此在宽厚板上采用分段式铁芯磁路设计能增强结晶器水箱的强度和使用稳定性要求。通过数值模拟的方法,对宽厚板铁芯分段式结晶器电磁搅拌的磁路结构进行计算和设计,考察了铁芯饱和尺寸和最大电流作用下的结晶器内磁场分布特征。通过一年的使用数据,使用宽厚板电磁搅拌、厚板探伤降级率、厚板夹渣降级率、厚板气泡降级率及热轧卷渣封锁率都有显著的下降,表面质量改善较好。 展开更多
关键词 宽厚板 分段 结晶器电磁搅拌 数值模拟 表面质量
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广西超大厚度ATB-25柔性基层全过程应用研究
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作者 周健 于国庆 +1 位作者 刘金哥 唐灿 《广东建材》 2024年第6期4-7,共4页
为研究广西超大厚度柔性路面结构,以田新高速公路项目设计参数与交通条件等,提出了20㎝厚ATB-25柔性上基层,共计38㎝厚沥青层的广西超大厚度柔性路面试验段结构。主要对ATB-25沥青混合料的目标配合比设计、生产配合比设计、实际施工配... 为研究广西超大厚度柔性路面结构,以田新高速公路项目设计参数与交通条件等,提出了20㎝厚ATB-25柔性上基层,共计38㎝厚沥青层的广西超大厚度柔性路面试验段结构。主要对ATB-25沥青混合料的目标配合比设计、生产配合比设计、实际施工配合比控制的结果进行全过程比对分析,全面开展了级配、沥青含量、马歇尔指标、水稳性能、低温性能、高温性能等技术性能试验,并对试验段工程完工后的结构层厚度、压实度、平整度、弯沉等路用性能指标进行了检测与评价,提出了超厚ATB-25柔性层分层施工质量控制关键内容。工程应用结果发现超厚ATB-25沥青层各技术指标和路用性能指标控制优良,符合规范和设计规定要求,值得推广应用。 展开更多
关键词 沥青路面 大厚度柔性基层 超厚ATB-25 全过程 质量控制
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宽厚板双边纵剪生产质量控制
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作者 张胜宏 《山西冶金》 CAS 2024年第6期215-216,219,共3页
随着科学技术不断进步,新产品、新技术不断涌现,市场对宽厚板需求日渐增多,对产品质量的要求也日益提高。双边纵剪系统作为宽厚板生产的重要组成部分,是保证产品质量的主要设备。基于滚切式双边剪的生产工艺流程,分析了宽厚板双边纵剪... 随着科学技术不断进步,新产品、新技术不断涌现,市场对宽厚板需求日渐增多,对产品质量的要求也日益提高。双边纵剪系统作为宽厚板生产的重要组成部分,是保证产品质量的主要设备。基于滚切式双边剪的生产工艺流程,分析了宽厚板双边纵剪生产中常见的生产质量问题,并提出了相应的控制改进措施。实际应用表明,采取改进措施后,有效降低了产品生产成本,提高了宽厚板的剪切质量和生产效率。 展开更多
关键词 宽厚板 双边纵剪 生产质量 控制
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叶片复烤机进料层厚度检测装置的研发
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作者 许然 沈美华 +2 位作者 韩剑 陈盼攀 李曾 《科技资讯》 2024年第8期102-104,共3页
烟叶复烤加工是烟叶加工过程中的重要环节,而叶片复烤机则是其中的主要设备。叶片复烤机通常由刮板喂料机、仓式喂料机、进料端口、干燥段、冷却段、回潮段、出料端及管路系统等组成。以对流传热方式干燥物料,在干燥过程中,物料的干燥... 烟叶复烤加工是烟叶加工过程中的重要环节,而叶片复烤机则是其中的主要设备。叶片复烤机通常由刮板喂料机、仓式喂料机、进料端口、干燥段、冷却段、回潮段、出料端及管路系统等组成。以对流传热方式干燥物料,在干燥过程中,物料的干燥速度与网面物料厚度呈负相关。在循环空气流速、温湿度一定的条件下,物料的铺层厚度较薄时,干燥效果较好。因此,进料层厚度的控制对加工质量具有一定的重要性。针对叶片复烤机进料层厚度检测装置开展研究,设计一种新型的厚度检测装置,以期进一步提高烟叶加工质量和效率。 展开更多
关键词 叶片复烤机 进料层厚度检测 装置研发 加工质量
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大厚度水泥稳定碎石半刚性基层一次性摊铺施工技术
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作者 刘卫东 《工程建设与设计》 2024年第4期220-222,共3页
以实际工程项目为例,探讨大厚度水泥稳定碎石半刚性基层一次性摊铺施工技术的应用和施工技术,并设计室内试验确定混合料最佳配合比,根据一次性摊铺施工技术的特点和工程项目的具体设计要求,严格控制材料施工质量,加强施工技术的应用质... 以实际工程项目为例,探讨大厚度水泥稳定碎石半刚性基层一次性摊铺施工技术的应用和施工技术,并设计室内试验确定混合料最佳配合比,根据一次性摊铺施工技术的特点和工程项目的具体设计要求,严格控制材料施工质量,加强施工技术的应用质量及机械配备,确保基层结构的安全稳定性。 展开更多
关键词 大厚度 水泥稳定碎石 施工工艺 质量控制
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大厚度C形梁R角质量影响因素研究
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作者 黄雪萌 房晓斌 +2 位作者 段蕾蕾 刘浩轩 王卓 《模具工业》 2024年第1期48-50,共3页
探讨了热压罐成型大厚度C形梁R角质量的影响因素,通过研究压力参数和压力传递方式,确定了影响R角质量稳定性的主要原因并提出了控制方法,为进一步提高实际工程中大厚度C形梁R角的结构质量和外形准确度奠定了基础。
关键词 复合材料 热压罐成型 大厚度C形梁 R角质量
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