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Tetramethylpyrazine and paeoniflorin combination(TMP-PF)alleviates atherosclerosis progress by reducing hyperlipemia and inhibiting plaque angiogenesis via the NR4A1/VEGFR2 pathway
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作者 Rong Yuan Qiqi Xin +8 位作者 Weili Shi Yu Miao Zhengchuan Zhu Yahui Yuan Ying Chen Xiaoning Chen Sean Xiao Leng Keji Chen Weihong Cong 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2642-2652,共11页
Atherosclerosis remains a great threat to human health worldwide.Previous studies found that tetramethylpyrazine(TMP)and paeonifl orin(PF)combination(TMP-PF)exerts anti-atherosclerotic effects in vitro.However,whether... Atherosclerosis remains a great threat to human health worldwide.Previous studies found that tetramethylpyrazine(TMP)and paeonifl orin(PF)combination(TMP-PF)exerts anti-atherosclerotic effects in vitro.However,whether TMP-PF improves atherosclerosis in vivo needs further exploration.The present study aims to assess the anti-atherosclerotic properties of TMP-PF in ApoE^(-/-)mice and explore the related molecule mechanisms.Results showed that TMP and high-dose TMP-PF decreased serum triglyceride and low-density lipoprotein cholesterol levels,suppressed vascular endothelial growth factor receptor 2(VEGFR2)and nuclear receptor subfamily 4 group A member 1(NR4A1)expression in aortic tissues,inhibited plaque angiogenesis,reduced plaque areas,and alleviated atherosclerosis in ApoE^(-/-)mice.Also,TMP-PF exhibited a better modulation effect than TMP or PF alone.However,NR4A1 agonist abolished the anti-atherosclerotic effects of TMP-PF.In conclusion,TMP-PF was first found to alleviate atherosclerosis progression by reducing hyperlipemia and inhibiting plaque angiogenesis via the NR4A1/VEGFR2 pathway,indicating that TMP-PF had a positive effect on reducing hyperlipemia and attenuating atherosclerosis development. 展开更多
关键词 ATHEROSCLEROSIS HYPERLIPEMIA ANGIOGENESIS plaque stability Chinese medicine TETRAMETHYLPYRAZINE PAEONIFLORIN
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Analysis of a New Toothbrushing Technique through Plaque Removal Success
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作者 Elhadi A. A. Shkorfu Serkan Kurt +2 位作者 Fatih Atalar Ali Olamat Aysel Ersoy 《Open Journal of Stomatology》 2024年第3期133-152,共20页
Background/Aims: Determining the levels of oral health and the quality of dental care are fundamental to building concepts of oral health. This study aims to assess toothbrushing techniques using a technical and physi... Background/Aims: Determining the levels of oral health and the quality of dental care are fundamental to building concepts of oral health. This study aims to assess toothbrushing techniques using a technical and physical model, clarifying how children and pre-adults learn to brush their teeth. Materials and Methods: Data were recorded from 23 participants, both male and female of various ages, using a proposed electronic toothbrush equipped with X-Y-Z axes pathways. The data, collected before and after training experiments, were processed with MATLAB to generate plots for the three axes. Results: The study revealed that most parameter values, such as Mean Difference Between Amplitudes (MAV, 6.00), Wilson Amplitude (WAMP, 179.419), and Average Amplitude Coupling (AAC, 1.270), decreased from before to after the experiments. Furthermore, the average overall epoch lengths (AVG) showed a 75% reduction in movement amplitude between the two experiments. Conclusion: Dentist observations indicated which brushing methods were acceptable or not. Analytical values suggest that individuals learn the toothbrushing technique effectively, and medical observations clearly demonstrate the success of the proposed method. 展开更多
关键词 Techno-Physical Toothbrushing Oral Hygiene Education Dental Technology plaque Analysis
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Outcomes of surgical correction of Peyronie’s disease with plaque excision and grafting: Comparison of testicular tunica vaginalis graft versus bovine pericardium graft
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作者 Ali Eslahi Faisal Ahmed +5 位作者 Mohammad Reza Askarpour Hossein-Ali Nikbakht Iman Shamohammadi Payam Ghasemi Hanieh Alimardani Bahareh Ebrahimi 《Asian Journal of Urology》 CSCD 2024年第3期497-503,共7页
Objective:Peyronie’s disease(PD)is an abnormal wound healing in the penile tunica albuginea.After fibrotic plaque excision,different graft materials have been used to repair the defects,but the optimal graft remains ... Objective:Peyronie’s disease(PD)is an abnormal wound healing in the penile tunica albuginea.After fibrotic plaque excision,different graft materials have been used to repair the defects,but the optimal graft remains unknown.This study aimed to compare the functional outcomes of testicular tunica vaginalis grafts and bovine pericardium grafts in patients with severe PD.Methods:A retrospective comparative study was conducted on 33 PD patients undergoing partial plaque excision and grafting from September 2015 to May 2021.The patients were divided into two groups depending on the type of graft used.For 15 patients in Group B,testicular tunica vaginalis grafts were used to repair the defect,while for 18 patients in Group A,bovine pericardium grafts were used.Data of the patient’s age,comorbidities,sexual function,penile curvature,postoperative complications,need for further treatment,change in penile length,and satisfaction were gathered and compared between the groups.Sexual function was evaluated using the 5-item version of the International Index of Erectile Function(IIEF-5),and a functional less than 20-degree penile curvature after surgery was considered a successful intervention.Results:There was no difference in age,comorbidities,degree of curvature,perioperative IIEF-5,operative time,plaque size,or complication rates.After surgery,a statistically significant improvement in curvature degree(p<0.05)and satisfactory penile appearance(p<0.05)were seen in both groups without any superiority between the two groups(p=0.423 and p=0.840,respectively).With a 30-month follow-up,the IIEF-5 was consistent in both groups,with no statistical significance between the groups(p=0.492).The main change in penile length during the operation was increased and still positive in the last follow-up in both groups without statistical significance(p=0.255 and p=0.101,respectively).Conclusion:Partial plaque excision and corporoplasty with both testicular tunica vaginalis or bovine pericardium grafts are equally effective in treating males with clinically significant PD. 展开更多
关键词 Peyronie's disease plaque excision Testicular tunica vaginalis graft Bovine pericardium graft
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Effect of arsenic on spatial pattern of radial oxygen loss and iron plaque formation in rice 被引量:1
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作者 吴川 黄柳 +4 位作者 薛生国 潘炜松 邹奇 William Hartley 莫竞瑜 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第2期413-419,共7页
The effects of different arsenic (As) treatments on spatial pattern of radial oxygen loss (ROL), iron (Fe) plaque formation and As accumulation in rice were investigated using three rice genotypes, planted under... The effects of different arsenic (As) treatments on spatial pattern of radial oxygen loss (ROL), iron (Fe) plaque formation and As accumulation in rice were investigated using three rice genotypes, planted under greenhouse conditions. Arsenic was applied to soil at 50 and 100 mg/kg, with untreated soil used as a control having an average As concentration of 8.5 mg/kg. It was demonstrated that the ratio of ROL in root tips to that at the root base slightly decreased with increasing As concentration, suggesting that the spatial ROL patterns in these groups may be shifted from the “tight” barrier towards the “partial” barrier form. Furthermore, increasing As concentration led to a increase in Fe plaque formation on root surfaces. In addition, root As concentrations of genotypes in 50 and 100 mg/kg As treatments were significantly higher than that of control treatment (P〈0.05). Grain As concentration of genotype Nanyangzhan (with lower ROL) was significantly higher (P〈0.05) than that of genotype CNT87059-3 with higher ROL. 展开更多
关键词 ARSENIC iron plaque RICE spatial pattern of ROL
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Angiographical and histopathologic study of atherosclerotic plaques in acute myocardial infarction
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作者 石怀银 王士雯 谭端军 《中国介入心脏病学杂志》 1998年第4期193-193,共1页
Objective Compare the morphology of atherosclerotic plaquesmgiographically and histopathologically in acute myocardialmfarction m order to accumulate experience in recognizing plaquerupture and thrombus by angiogrames... Objective Compare the morphology of atherosclerotic plaquesmgiographically and histopathologically in acute myocardialmfarction m order to accumulate experience in recognizing plaquerupture and thrombus by angiogrames.Material and methods 16postmortem cases of acute myocardial infarction were studied.The coronary arteries were romoved en block,filled with barium the lumen and ridiographed.Then the arteries wereontinuously insetted and routin HE sections were made.Results 16 cases had plaque ruptures and thrombi.Among the total98 blocks,21 had plaque ruptures on which 20 thrombiccur(95.23%).while the other 777 unrupured blocks had only 2hrombi(0.25%).The difference was significant(p【0.001).Therupture mostly occur on unstable plaques.The ruptured plaqueswith thrombi had different angiographical morphology withunruptured plaques.The former had irregular borders andunraluminal lucencies;while the Iatter had smooth borders and nointraluminal lucencies.Conclusions Plaque ruprure withthrumbus was the major cause of acute myocardial infarction andthe ruptured plaques with thrombus had different angiographicalapperances with unruptured plaques. 展开更多
关键词 plaqueS THROMBUS unstable RUPTURED ARTERIES accumulate LUMEN mostly irregular plaque
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Helicobacter pylori in dental plaque and stomach of patients from Northern Brazil 被引量:29
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作者 Mnica Baraúna Assumpo Luisa Caricio Martins +4 位作者 Hivana Patricia Melo Barbosa Katarine Antonia dos Santos Barile Sintia Silva de Almeida Paulo Pimentel Assumpo Tereza Cristina de Oliveira Corvelo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第24期3033-3039,共7页
AIM: To establish whether virulence factor genes vacA and cagA are present in Helicobacter pylori (H. pylori) retrieved from gastric mucosa and dental plaque in pa-tients with dyspepsia. METHODS: Cumulative dental pla... AIM: To establish whether virulence factor genes vacA and cagA are present in Helicobacter pylori (H. pylori) retrieved from gastric mucosa and dental plaque in pa-tients with dyspepsia. METHODS: Cumulative dental plaque specimens and gastric biopsies were submitted to histological exami-nation, rapid urease test and polymerase chain reac-tion (PCR) assays to detect the presence of cagA and vacA polymorphisms.RESULTS: Detection of H. pylori from dental plaque and gastric biopsy samples was greater by PCR com-pared to histological examination and the rapid ure-ase test. DNA from H. pylori was detected in 96% of gastric mucosa samples and in 72% of dental plaque samples. Sixty-three (89%) of 71 dental plaque sam-ples that were H. pylori-positive also exhibited identical vacA and cagA genotypes in gastric mucosa. The most common genotype was vacAs1bm1 and cagA positive, either in dental plaque or gastric mucosa. These viru-lent H. pylori isolates were involved in the severity of clinical outcome.CONCLUSION: These pathogenic strains were found simultaneously in dental plaque and gastric mucosa, which suggests that gastric infection is correlated with the presence of H. pylori in the mouth. 展开更多
关键词 Helicobacter pylori Gastric mucosa Dental plaque CAGA VACA
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Role of dental plaque,saliva and periodontal disease in Helicobacter pylori infection 被引量:16
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作者 Pradeep S Anand Kavitha P Kamath Sukumaran Anil 《World Journal of Gastroenterology》 SCIE CAS 2014年第19期5639-5653,共15页
Helicobacter pylori (H. pylori) infection is one of the most common bacterial infections in humans. Although H. pylori may be detected in the stomach of approximately half of the world&#x02019;s population, the me... Helicobacter pylori (H. pylori) infection is one of the most common bacterial infections in humans. Although H. pylori may be detected in the stomach of approximately half of the world&#x02019;s population, the mechanisms of transmission of the microorganism from individual to individual are not yet clear. Transmission of H. pylori could occur through iatrogenic, fecal-oral, and oral-oral routes, and through food and water. The microorganism may be transmitted orally and has been detected in dental plaque and saliva. However, the role of the oral cavity in the transmission and recurrence of H. pylori infection has been the subject of debate. A large number of studies investigating the role of oral hygiene and periodontal disease in H. pylori infection have varied significantly in terms of their methodology and sample population, resulting in a wide variation in the reported results. Nevertheless, recent studies have not only shown that the microorganism can be detected fairly consistently from the oral cavity but also demonstrated that the chances of recurrence of H. pylori infection is more likely among patients who harbor the organism in the oral cavity. Furthermore, initial results from clinical trials have shown that H. pylori-positive dyspeptic patients may benefit from periodontal therapy. This paper attempts to review the current body of evidence regarding the role of dental plaque, saliva, and periodontal disease in H. pylori infection. 展开更多
关键词 Helicobacter pylori Dental plaque SALIVA Oral cavity PERIODONTITIS Periodontal therapy
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Assessment of neovascularization within carotid plaques in patients with ischemic stroke 被引量:29
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作者 Wilbert S Aronow Chandra K Nair David Cosgrove 《World Journal of Cardiology》 CAS 2010年第4期89-97,共9页
AIM:To assess neovascularization within human ca-rotid atherosclerotic soft plaques in patients with isch-emic stroke.METHODS:Eighty-one patients with ischemic stroke and 95 patients without stroke who had soft athero... AIM:To assess neovascularization within human ca-rotid atherosclerotic soft plaques in patients with isch-emic stroke.METHODS:Eighty-one patients with ischemic stroke and 95 patients without stroke who had soft athero-sclerotic plaques in the internal carotid artery were studied.The thickest soft plaque in each patient was examined using contrast-enhanced ultrasound.Time-intensity curves were collected from 5 s to 3 min after contrast injection.The neovascularization within the plaques in the internal carotid artery was evaluated using the ACQ software built into the scanner by 2 of the experienced investigators who were blinded to the clinical history of the patients.RESULTS:Ischemic stroke was present in 7 of 33 patients(21%) with grade Ⅰ plaque,in 14 of 51 pa-tients(28%) with grade Ⅱ plaque,in 26 of 43 patients(61%) with grade Ⅲ plaque,and in 34 of 49 patients(69%) with grade Ⅳ plaque(P < 0.001 comparing grade Ⅳ plaque with grade I plaque and with grade Ⅱ plaque and P = 0.001 comparing grade Ⅲ plaque with grade Ⅰ plaque and with grade Ⅱ plaque).Analysis of the time intensity curves revealed that patients with ischemic stroke had a significantly higher intensity of enhancement(IE) than those without ischemic stroke(P < 0.01).The wash-in time(WT) of plaque was signifi-cantly shorter in stroke patients(P < 0.05).The sensi-tivity and specificity for IE in the plaque were 82% and 80%,respectively,and for WT were 68% and 74%,respectively.There was no significant difference in the peak intensity or time to peak between the 2 groups.CONCLUSION:This study shows that the higher the grade of plaque enhancement,the higher the risk of ischemic stroke.The data suggest that the presence of neovascularization is a marker for unstable plaque. 展开更多
关键词 CAROTID artery plaqueS Cerebral INFARCTION CONTRAST-ENHANCED ultrasonography Ischemic stroke NEOVASCULARIZATION
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Contrast-enhanced ultrasound imaging of the vasa vasorum of carotid artery plaque 被引量:13
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作者 Ze-Zhou Song Yan-Ming Zhang 《World Journal of Radiology》 CAS 2015年第6期131-133,共3页
The vasa vasorum of carotid artery plaque is a novel marker of accurately evaluating the vulnerability of carotid artery plaque, which was associated with symptomatic cerebrovascular and cardiovascular disease. The pr... The vasa vasorum of carotid artery plaque is a novel marker of accurately evaluating the vulnerability of carotid artery plaque, which was associated with symptomatic cerebrovascular and cardiovascular disease. The presence of ultrasound contrast agents in carotid artery plaque represents the presence of the vasa vasorum in carotid artery plaque because the ultrasoundcontrast agents are strict intravascular tracers. Therefore, contrast-enhanced ultrasound(CEUS) is a novel and safe imaging modality for evaluating the vasa vasorum in carotid artery plaque. However, there are some issues that needs to be assessed to embody fully the clinical utility of the vasa vasorum in carotid artery plaque with CEUS. 展开更多
关键词 VASA vasorum CAROTID ARTERY plaque VULNERABILITY CONTRAST-ENHANCED ultrasound
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Value of superb micro-vascular imaging in predicting ischemic stroke in patients with carotid atherosclerotic plaques 被引量:18
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作者 De-Bin Yang Jie Zhou +2 位作者 Lan Feng Rong Xu Ying-Chun Wang 《World Journal of Clinical Cases》 SCIE 2019年第7期839-848,共10页
BACKGROUND Unstable carotid atherosclerotic plaques are prone to cause ischemic stroke.Contrast-enhanced ultrasound(CEUS) is the primary method of assessing plaque stability, but CEUS cannot be a method for screening ... BACKGROUND Unstable carotid atherosclerotic plaques are prone to cause ischemic stroke.Contrast-enhanced ultrasound(CEUS) is the primary method of assessing plaque stability, but CEUS cannot be a method for screening for unstable plaque. The emergence of superb micro-vascular imaging(SMI) offers the possibility of clinically screening for unstable plaque AIM To investigate the value of SMI in predicting ischemic stroke in patients with carotid atherosclerotic plaques.METHODS Patients with carotid atherosclerotic plaques(luminal stenosis of 50%-70%) were enrolled into the present study. All patients received conservative medication.The patient's clinical baseline data, serological data, CEUS and SMI data were analyzed. All patients underwent a 3-year follow-up. The follow-up endpoint was the occurrence of ischemic stroke and patients were divided into stroke group and non-stroke group according to whether the prognosis occurred or not.Subsequently, the difference in clinical data was compared, the correlation of SMI and CEUS was analyzed, and multiple Cox regression and receiver operating characteristic curve were applied to investigate the value of SMI and CEUS in predicting cerebral arterial thrombosis in three years.RESULTS In this study, 43 patients were enrolled in the stroke group and 82 patients were enrolled in the non-stroke group. Cox regression revealed that SMI level(P =0.013) and enhancement intensity(P = 0.032) were the independent factors influencing ischemic stroke. There was a positive correlation between SMI level and enhancement intensity(r = 0.737, P = 0.000). The area under curve of SMI level predicting ischemic stroke was 0.878. The best diagnostic point was ≥ level Ⅱ, and its sensitivity and specificity was 86.05% and 79.27%. The area under curve of enhancement intensity predicting ischemic stroke was 0.890. The best diagnostic point was 9.92 db, and its sensitivity and specificity was 88.37% and89.02%. As the SMI level gradually increased, the incidence of ischemic stroke increased gradually(X^2 = 108.931, P = 0.000).CONCLUSION SMI can be used as a non-invasive method of screening for unstable plaques and may help prevent ischemic stroke. 展开更多
关键词 SUPERB micro-vascular imaging CONTRAST-ENHANCED ultrasound CAROTID ATHEROSCLEROTIC plaqueS Ischemic stroke
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Progress in atherosclerotic plaque imaging 被引量:10
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作者 Giulia Soloperto Sergio Casciaro 《World Journal of Radiology》 CAS 2012年第8期353-371,共19页
Cardiovascular diseases are the primary cause of mortality in the industrialized world,and arterial obstruction, triggered by rupture-prone atherosclerotic plaques,lead to myocardial infarction and cerebral stroke.Vul... Cardiovascular diseases are the primary cause of mortality in the industrialized world,and arterial obstruction, triggered by rupture-prone atherosclerotic plaques,lead to myocardial infarction and cerebral stroke.Vulnerable plaques do not necessarily occur with flow-limiting stenosis,thus conventional luminographic assessment of the pathology fails to identify unstable lesions.In this review we discuss the currently available imaging modalities used to investigate morphological features and biological characteristics of the atherosclerotic plaque. The different imaging modalities such as ultrasound, magnetic resonance imaging,computed tomography, nuclear imaging and their intravascular applications are illustrated,highlighting their specific diagnostic potential.Clinically available and upcoming methodologies are also reviewed along with the related challenges in their clinical translation,concerning the specific invasiveness, accuracy and cost-effectiveness of these methods. 展开更多
关键词 ATHEROSCLEROSIS DIAGNOSTIC IMAGING plaque characterization
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Relationship between arterial atheromatous plaque morphology and platelet-associated miR-126 and miR-223 expressions 被引量:8
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作者 Heng-Song Tian Qing-Guo Zhou Fang Shao 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2015年第4期309-314,共6页
Objective:To study the expression of miR-126 and miR-223 in platelet of rabbit arterial plaque models,and explore its correlation with plaque morphology.Methods:Rabbit arterial plaque models were established,periphera... Objective:To study the expression of miR-126 and miR-223 in platelet of rabbit arterial plaque models,and explore its correlation with plaque morphology.Methods:Rabbit arterial plaque models were established,peripheral blood of models and control animals was collected.Plaque morphologies were divided into typeⅠ.typeⅡand typeⅢbased on angiography plaque morphology and Ambrose method.Platelet isolation kit was applied to isolate and purify peripheral blood platelets,CD45 immunomagnetic beads were used to remove the residual white blood cells.The miRNAs of platelets was extracted by miRNA Isolation Kit,and expressions of miR-126 and miR-223 of the platelets samples were detected by Real-time PCR.The correlation between plaque morphology and platelet-associated miR-126 and miR-223 expressions were analyzed.Expressions of target gene VCAM-1 and P2Y12 receptors of miR-126 and miR-223 in the atherosclerosis plaque of rabbit model were detected by Western blot.Results:Relative expression levels of miR-126 and miR-223 in the model group were 0.27±0.10 and 0.71±0.14,respectively.Plaque morphology was divided into typesⅠ,ⅡandⅢ;and miR-126 and miR-223 expression levels were detected in each type.Expression levels of miR-126 in each type were 0.42±0.07,0.17±0.11 and 0.22±0.15,respectively;and expression levels of miR-223 in each type are 0.68±0.02,0.57±0.06 and 0.88±0.10.respectively.Relative to the control group,miR-126 and miR-223 known target genes in VCAM-1 and P2Y12receptors increased platelets in rabbit atherosclerotic plaque models(P<0.05).Conclusions:Relative to normal control animals,miR-126 and miR-223 platelets were reduced in the rabbit atherosclerotic plaque model group(P<0.05).In the typeⅡplaque morphology group,miR-126 was greatly reduced;and there is no significant correlation between miR-223 and plaque morphology. 展开更多
关键词 PLATELETS MIR-126 miR-223 Coronary heart disease ATHEROSCLEROTIC plaque
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Effect of microbial mediated iron plaque reduction on arsenic mobility in paddy soil 被引量:11
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作者 WANG Xinjun CHEN Xueping +2 位作者 YANG Jing WANG Zhaosu SUN Guoxin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第11期1562-1568,共7页
The potential of microbial mediated iron plaque reduction, and associated arsenic (As) mobility were examined by iron reducing bacteria enriched from As contaminated paddy soil. To our knowledge, this is the first t... The potential of microbial mediated iron plaque reduction, and associated arsenic (As) mobility were examined by iron reducing bacteria enriched from As contaminated paddy soil. To our knowledge, this is the first time to report the impact of microbial iron plaque reduction on As mobility. Iron reduction occurred during the inoculation of iron reducing enrichment culture in the treatments with iron plaque and ferrihydrite as the electron acceptors, respectively. The Fe(II) concentration with the treatment of anthraquinone-2, 6-disulfonic acid (AQDS) and iron reducing bacteria increased much faster than the control. Arsenic released from iron plaque with the iron reduction, and a significant correlation between Fe(II) and total As in culture was observed. However, compared with control, the increasing rate of As was inhibited by iron reducing bacteria especially in the presence of AQDS. In addition, the concentrations of As(III) and As(V) in abiotic treatments were higher than those in the biotic treatments at day 30. These results indicated that both microbial and chemical reductions of iron plaque caused As release from iron plaque to aqueous phase, however, microbial iron reduction induced the formation of more crystalline iron minerals, leading to As sequestration. In addition, the presence of AQDS in solution can accelerate the iron reduction, the As release from iron plaque and subsequently the As retention in the crystalline iron mineral. Thus, our results suggested that it is possible to remediate As contaminated soils by utilizing iron reducing bacteria and AQDS. 展开更多
关键词 iron reducing bacteria iron plaque ARSENIC anthraquinone-2 6-disulfonic acid (AQDS) paddy soil FERRIHYDRITE
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Effect of manganese on the catalytic performance of an iron-manganese bimetallic catalyst for light olefin synthesis 被引量:16
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作者 Tingzhen Li Hulin Wang +2 位作者 Yong Yang Hongwei Xiang Yongwang Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第4期624-632,共9页
A systematic study was carried out to investigate the promotion effect of manganese on the performance of a coprecipitated iron-manganese bimetallic catalyst for the light olefins synthesis from syngas. The catalyst s... A systematic study was carried out to investigate the promotion effect of manganese on the performance of a coprecipitated iron-manganese bimetallic catalyst for the light olefins synthesis from syngas. The catalyst samples were characterized by N2 physisorption, transmis- sion electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (XRD), Mossbauer spectroscopy, H2- differential thermogravimetric analysis (H2-DTG), CO temperature-programmed reduction (CO-TPR) and CO2 temperature-programmed des- orption (CO2-TPD). The Fischer-Tropsch synthesis (FTS) performance of the catalyst was measured at 1.5 MPa, 250 ℃ and syngas with H2/CO ratio of 2.0. The characterization results indicated that the addition of manganese decreases the catalyst crystallite size, and improves the catalyst BET surface area and pore volume. The presence of manganese suppresses the catalyst reduction and carburization in H2, CO and syngas, respectively. The addition of manganese improves the catalytic activity of water-gas shift reaction and suppresses the oxidation of iron carbides in the FTS reaction. The incorporation of manganese improves the catalyst surface basicity and results in a significant improvement in the selectivities to light olefins and heavy hydrocarbons (C5+), and furthermore an inhibition of methane formation in FTS. The pure iron catalyst (Mn-00) has the highest initial FTS catalytic activity (65%) and the lowest selectivity (17.35 wt%) to light olefins (C2=-C4=). The addition of an appropriate amount of manganese can improve the catalyst FTS activity. 展开更多
关键词 light olefin Fischer-Tropsch synthesis iron-manganese bimetallic catalyst CARBURIZATION
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Elemental Composition and Geochemical Characteristics of Iron-Manganese Nodules in Main Soils of China 被引量:11
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作者 TAN Wen-Feng LIU Fan +2 位作者 LI Yong-Hua HU Hong-Qing HUANG Qiao-Yun 《Pedosphere》 SCIE CAS CSCD 2006年第1期72-81,共10页
Elemental composition and geochemical characteristics of iron-manganese nodules from nine main soils in China were studied by chemical and multivariate statistical analyses to better understand the reactions and funct... Elemental composition and geochemical characteristics of iron-manganese nodules from nine main soils in China were studied by chemical and multivariate statistical analyses to better understand the reactions and functions of iron-manganese nodules in soils and sediment. Compared to the corresponding soils, Mn, Ba, Cd, Co and Pb had strong accumulation, Ni had moderate accumulation, while Ca, Cu, Fe, Na, P, Sr and Zn accumulated to a minor degree in the iron-manganese nodules. In contrast, Si, Al, K, Mg and Ti were reduced in the iron-manganese nodules. The contents of Ba, Cd, Co, Cu, Ni, Pb and Zn were positively and significantly correlated with that of MnO2 in the iron-manganese nodules, while the contents of Cr, Cu, Ni, Pb and Zn were positively and significantly correlated with that of Fe2O3 in soils. Based on a principle component analysis, the elements of iron-manganese nodules were divided into four groups: 1) Mn, Ba, Cd, Co, Cu, Li, Ni, Pb and Zn that were associated with Mn oxides, 2) Fe, Cr and P that were associated with Fe oxides, 3) Si, K, and Mg that were included in the elemental composition of phyllosilicate, and 4) Ca, Na, Al and Ti that existed in todorokite, birnessite, lithiophorite and phyllosilicate. It was suggested that accumulation, mineralization and specific adsorption were involved in the formation processes of soil iron-manganese nodules. 展开更多
关键词 elemental composition geochemical characteristics iron-manganese nodule soil
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Correlation between Enhanced Intensity of Atherosclerotic Plaque at Contrast-enhanced Ultrasonography and Density of Histological Neovascularization 被引量:5
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作者 孙杰 刘琨 +2 位作者 汤乔颖 张伟 邓又斌 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2013年第3期443-446,共4页
Summary: The feasibility of contrast-enhanced ultrasonography in the assessment of atherosclerotic plaque neovascularization and its relation to histological findings were investigated. Abdominal aortic atherosclerot... Summary: The feasibility of contrast-enhanced ultrasonography in the assessment of atherosclerotic plaque neovascularization and its relation to histological findings were investigated. Abdominal aortic atherosclerotic plaque model was induced in 25 New Zealand white rabbits by a combination of high cholesterol-rich diet and balloon aortic denudation. Standard and contrast-enhanced ultrasonography was performed at the 16th week of the model induction period. The plaques were classified as echogenic plaques or echolucent plaques according to their echogenicity at standard ultrasonography. The maxi- mum thickness of plaque was measured in the longitudinal section. Time intensity curve was used to quantify the enhanced intensity of the plaque. Animals were euthanized and abdominal aortas were har- vested for histological staining of CD31 to evaluate the neovascularization density of atherosclerotic plaque. The results showed that the echolucent plaques had higher enhanced intensity during con- trast-enhanced ultrasonography and higher neovascularization density at CD31 staining than the echo- genic plaques. The enhanced intensity of atherosclerotic plaque and its ratio to lumen were well corre- lated with histological neovascularization density (r=0.75, P〈0.001; r=0.68, P〈0.001, respectively). However, the maximum thickness of plaque was not correlated with neovascularization density (r=0.235, P=0.081). These findings demonstrated that the enhanced intensity in the plaque and ratio of enhanced intensity to that in the lumen of abdominal aorta may be more accurate in the evaluation of plaque neovascularization than maximum thickness. Our study indicates that contrast-enhanced ultra- sonography provides us a reliable method for the evaluation of plaque neovascularization. 展开更多
关键词 contrast-enhanced ultrasonography plaque enhanced intensity histopathological correlation
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Evaluation of Carotid Plaque Neovascularization in Patients with Diabetes Mellitus by Contrast-enhanced Ultrasonography 被引量:5
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作者 熊莉 黎鹏 赵博文 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2014年第1期29-32,共4页
This study investigated the relationship between carotid plaque neovascularization and diabetes mellitus(DM) by using contrast-enhanced ultrasonography. Contrast-enhanced ultrasonography was performed in 104 patient... This study investigated the relationship between carotid plaque neovascularization and diabetes mellitus(DM) by using contrast-enhanced ultrasonography. Contrast-enhanced ultrasonography was performed in 104 patients with carotid plaque thicker than 2.0 mm. There were 36 patients with DM and 68 patients without DM. The enhanced intensity in the plaque and the ratio of enhanced intensity in the plaque to that in the lumen of the carotid artery in patients with DM were significantly greater than those in patients without DM. Our study demonstrated that the enhanced intensity in patients with DM is greater than that their counterparts without DM, suggesting that carotid plaque in DM patients may have more neovessels and may be more vulnerable. 展开更多
关键词 vulnerable plaque contrast-enhanced ultrasonography diabetes mellitus neovasculari-zation
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Relationship between Levels of Serum C-Reactive Protein,Leucocyte Count and Carotid Plaque in Patients with Ischemic Stroke 被引量:4
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作者 郭毅 姜昕 +3 位作者 周志斌 陈实 赵宏文 李富康 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2003年第3期263-265,共3页
In order to study the relationship between serum C-reactive protein (CRP) levels, leukocyte count and carotid plaque in patients with ischemic stroke, carotid duplex examination was performed by high-definition imagin... In order to study the relationship between serum C-reactive protein (CRP) levels, leukocyte count and carotid plaque in patients with ischemic stroke, carotid duplex examination was performed by high-definition imaging (HDI) 5000 triplex system. Serum CRP was measured by nephelometry within 72 h after index ischemic stroke. A lesion was considered a plaque in the presence of a maximum intimal-medial wall thickness (IMT) 1.2 mm. Results of carotid ultrasonography were divided into two groups: M1, normal (IMT <1.2 mm) and M2, abnormal (IMT ≥1.2 mm). The results showed that the mean age of M2 was significantly older than that of M1 (69.7±10.4 versus 62.5±9.6, P =0.001). The patients with hypertension and diabetes mellitus (78 %, 35 % respectively)in M2 were significantly more than those (52 %, 18 % respectively) in M1 ( P <0.01, P <0.05). There were 32 (65 % ) patients with elevated CRP levels in M2, but 33 (46 %) patients with elevated CRP levels in M1, with the difference being significant between the two groups ( P <0.05). The levels of serum glucose and leukocyte count (8.1±5.5, 10.3±4.0, respectively) in abnormal CRP group were significantly higher than that of normal CRP group (6.4±2.8, 8.7±3.4) ( P <0.05, P <0.05); elevated CRP levels was found in 42 (62 %) patients with territory infarction and 23 (43 %) patients with lacunar infarction respectively, with the difference being significant between these two groups ( P <0.05). It was concluded that the elevation of CRP levels was an significant clinical index for carotid plaque in patients with acute cerebral infarction. 展开更多
关键词 C-reactive protein ischemic stroke LEUKOCYTE carotid plaque
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Association between Coronary Atherosclerotic Plaque Composition and Cardiovascular Disease Risk 被引量:5
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作者 LI Lin WANG Long +14 位作者 LIU Shan Shan ZHAO Zhi Yun LI Mian WANG Tian Ge XU Min LU Jie Li CHEN Yu Hong WANG Shuang Yuan DAI Meng HOU Ya Nan WU Xue Yan MA Li Na WANG Wei Qing XU Yu BI Yu Fang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2019年第2期75-86,共12页
Objective The objective of this study is to determine whether coronary atherosclerotic plaque composition is associated with cardiovascular disease(CVD) risk in Chinese adults. Methods We performed a cross-sectional a... Objective The objective of this study is to determine whether coronary atherosclerotic plaque composition is associated with cardiovascular disease(CVD) risk in Chinese adults. Methods We performed a cross-sectional analysis in 549 subjects without previous diagnosis or clinical symptoms of CVD in a community cohort of middle-aged Chinese adults. The participants underwent coronary computed tomography(CT) angiography for the evaluation of the presence and composition of coronary plaques. CVD risk was evaluated by the Framingham risk score(FRS) and the 10-year atherosclerotic cardiovascular disease(ASCVD) risk score. Results Among the 549 participants, 267(48.6%) had no coronary plaques, 201(36.6%) had noncalcified coronary plaques, and 81(14.8%) had calcified or mixed coronary plaques. The measures of CVD risk including FRS and ASCVD risk score and the likelihood of having elevated FRS significantly increased across the groups of participants without coronary plaques, with noncalcified coronary plaques, and with calcified or mixed coronary plaques. However, only calcified or mixed coronary plaques were significantly associated with an elevated ASCVD risk score [odds ratio(OR) 2.41; 95% confidence interval(CI) 1.09-5.32] compared with no coronary plaques, whereas no significant association was found for noncalcified coronary plaques and elevated ASCVD risk score(OR 1.25; 95% CI 0.71-2.21) after multivariable adjustment. Conclusion Calcified or mixed coronary plaques might be more associated with an elevated likelihood of having CVD than noncalcified coronary plaques. 展开更多
关键词 Coronary plaque COMPOSITION FRAMINGHAM RISK SCORE 10-year ATHEROSCLEROTIC cardiovascular disease RISK SCORE
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Noninvasive diagnosis of vulnerable coronary plaque 被引量:4
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作者 Eduardo Pozo Pilar Agudo-Quilez +4 位作者 Antonio Rojas-González Teresa Alvarado María José Olivera Luis Jesús Jiménez-Borreguero Fernando Alfonso 《World Journal of Cardiology》 CAS 2016年第9期520-533,共14页
Myocardial infarction and sudden cardiac death are frequently the first manifestation of coronary artery disease.For this reason,screening of asymptomatic coronary atherosclerosis has become an attractive field of res... Myocardial infarction and sudden cardiac death are frequently the first manifestation of coronary artery disease.For this reason,screening of asymptomatic coronary atherosclerosis has become an attractive field of research in cardiovascular medicine.Necropsy studies have described histopathological changes associated with the development of acute coronary events.In this regard,thin-cap fibroatheroma has been identified as the main vulnerable coronary plaque feature.Hence,many imaging techniques,such as coronary computed tomography,cardiac magnetic resonance or positron emission tomography,have tried to detect noninvasively these histomorphological characteristics with different approaches.In this article,we review the role of these diagnostic tools in the detection of vulnerable coronary plaque with particular interest in their advantages and limitations as well as the clinical implications of the derived findings. 展开更多
关键词 ATHEROSCLEROSIS VULNERABLE CORONARY plaque Diagnosis CARDIAC COMPUTED tomography CARDIAC magnetic resonance
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