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61.
李楠 《医疗保健器具》2014,(9):1163-1164
目的研究与分析阿司匹林、普罗布考和阿托伐他汀钙三药联用治疗颈动脉硬化患者的不稳定斑块的作用。方法对我院2010年3月至2012年5月间126例颈动脉硬化患者随机分为PAS组与AS组各63例,AS组患者给予阿司匹林100mg/日和阿托伐他汀钙20mg/日,PAS组在As组基础上加用普罗布考500mg/次,2次/日,在治疗后6个月进行颈动脉超声检测。比较与分析颈动脉斑块的面积和性质的变化。结果治疗后6个月,两组患者不稳定斑块面积均有减小,PAS组不稳定斑块的面积减小程度大于As组,差异具有统计学意义(P<0.05),PAS组不稳定斑块数目减少程度大于AS组。结论PAS疗法对消除颈动脉粥样硬化斑块具有显著作用,普罗布考在降血脂及抗血小板的基础上可进一步减轻和消退颈动脉不稳定斑块.延缓动脉粥样硬化的形成和发展.此疗法具有显著优势.在临床更具应用价值.  相似文献   
62.
动脉粥样硬化易损斑块破裂是导致缺血性卒中的主要原因。与组织病理学对照研究证实,
高分辨率磁共振成像可以无创性评价动脉粥样硬化斑块的负荷、成分及其易损性。大量研究显示,
脑血管粥样硬化斑块的磁共振表现特征与缺血性卒中具有明显的相关性。本文将从磁共振斑块成
分特征与缺血性脑血管事件的相关性方面进行综述,为缺血性卒中的病因学诊断和疾病的预防提供
重要依据。  相似文献   
63.

Background

Some plaques lead to ST-segment elevation myocardial infarction (STEMI), whereas others cause non-ST-segment elevation acute coronary syndrome (NSTEACS). We used angiography and intravascular ultrasound (IVUS) to investigate the difference of culprit lesion morphologies in ACS.

Methods

Consecutive 158 ACS patients whose culprit lesions were imaged by preintervention IVUS were enrolled (STEMI = 81; NSTEACS = 77). IVUS and angiographic findings of the culprit lesions, and clinical characteristics were compared between the groups.

Results

There were no significant differences in patients' characteristics except for lower rate of statin use in patients with STEMI (20% vs 44%, p = 0.001). Although angiographic complex culprit morphology (Ambrose classification) and thrombus were more common in STEMI than in NSTEACS (84% vs 62%, p = 0.002; 51% vs 5%, p < 0.0001, respectively), SYNTAX score was lower in STEMI (8.6 ± 5.4 vs 11.5 ± 7.1, p = 0.01). In patients with STEMI, culprit echogenicity was more hypoechoic (64% vs 40%, p = 0.01), and the incidence of plaque rupture, attenuation and “microcalcification” were significantly higher (56% vs 17%, p < 0.0001; 85% vs 69%, p = 0.01; 77% vs 61%, p = 0.04, respectively). Furthermore, the maximum area of ruptured cavity, echolucent zone and arc of microcalcification were significantly greater in STEMI compared with NSTEACS (1.80 ± 0.99 mm2 vs 1.13 ± 0.86 mm2, p = 0.006; 1.52 ± 0.74 mm2 vs 1.21 ± 0.81 mm2, p = 0.004; 99.9 ± 54.6° vs 77.4 ± 51.2°, p = 0.01, respectively). Quantitative IVUS analysis showed that vessel and plaque area were significantly larger at minimum lumen area site (16.6 ± 5.4 mm2 vs 14.2 ± 5.5 mm2, p = 0.003; 13.9 ± 5.1 mm2 vs 11.6 ± 5.2 mm2, p = 0.003, respectively).

Conclusion

Morphological feature (outward vessel remodeling, plaque buildup and IVUS vulnerability of culprit lesions) might relate to clinical presentation in patients with ACS.  相似文献   
64.
65.
Cardiovascular imaging plays an important role in the identification and characterization of the vulnerable plaque. A major goal is the ability to identify individuals at risk of plaque rupture and developing an acute coronary syndrome. Early recognition of rupture‐prone atherosclerotic plaques may lead to the development of pharmacologic and interventional strategies to reduce acute coronary events.We review state‐of‐the‐art cardiovascular imaging for identification of the vulnerable plaque. There is ample evidence of a close relationship between plaque morphology and patient outcome, but molecular imaging can add significant information on tissue characterization, inflammation and subclinical thrombosis. Additionally, identifying arterial wall exposed to high shear stress may further identify rupture‐prone arterial segments. These new modalities may help reduce the individual, social and economic burden of cardiovascular disease.  相似文献   
66.
Atherosclerosis is considered a chronic inflammatory disease of arteries associated with the aging process. Many risk factors have been identified and they are mainly related to life-styles, gene-environment interactions and socioeconomic status. Carotid and coronary artery diseases are the two major atherosclerotic conditions, being the primary cause of stroke and heart attack, respectively. Nevertheless, carotid plaque assumes particular aspects not only for the specific molecular mechanisms, but also for the types of atheroma which may be associated with a better or a worst prognosis. The identification of circulating blood biomarkers able to distinguish carotid plaque types (stable or vulnerable) is a crucial step for the improvement of adequate therapeutic approaches avoiding or delaying endarterectomy in the oldest old individuals (> 80 years), a population predicted to growth in the next years. The review highlights the most recent knowledge on carotid plaque molecular mechanisms, focusing on microRNAs (miRs), as a site-specific accelerated aging within the conceptual framework of Geroscience for new affordable therapies.  相似文献   
67.
The aim of the present study was to determine the chemokine RANTES (regulated on activation, normal T-cell expressed, and secreted) levels in plasma and atherosclerotic plaques and to assess their diagnostic efficacy in the evaluation of vulnerable plaques. The rabbit models of vulnerable atherosclerotic plaque (VAP) were established by high fat diet and pharmaceutical triggering. The serum RANTES levels of VAP group (91.97 ± 8.51 ng/ml) were significantly higher than those of AS (atherosclerosis) group (50.03 ± 2.92 ng/ml). Consistently, the mRNA and protein of RANTES in vulnerable atherosclerotic plaques were also obviously up-regulated compared to AS group (P < 0.01). Moreover, corrected plaque area and vulnerability index of VAP group proved to be significantly higher than AS group. The correlation coefficient between RANTES and plaque vulnerability indicated that RANTES, especially plaque RANTES, was positively correlated with VAP. In addition, increased expression of nuclear factor kappa B p65 (NF-κB p65) was observed in VAP group compared to AS group (P < 0.05), which partly accounted for the increased RANTES levels. In conclusion, positive associations between RANTES and plaque vulnerability suggest that higher RANTES levels may be associated with atherosclerosis and high-risk plaques. Our study highlights the utility of both serum and plaque RANTES levels as indicators of plaque vulnerability in the field of preventive cardiology.  相似文献   
68.
《Archives of oral biology》2014,59(12):1384-1390
ObjectiveSince some probiotic bacteria are cariogenic themselves, their suitability for caries management is questionable. Inactivated bacteria or their supernatants have been found to exert probiotic effects, whilst having several advantages compared with living bacteria. We hypothesized that viable and heat-inactivated Bifidobacterium animalis BB12 reduces the cariogenicity of Streptococcus mutans (SM) in vitro.DesignWe assessed mono- and mixed species biofilms of SM and viable or heat-inactivated BB12. Biofilms were grown in a continuous-culture-system under cariogenic conditions on smooth proximal enamel or cavitated dentine. For each of eight experimental subsets (4 biofilms × 2 hard-tissue conditions), a total of 32 specimens was used. After 10 days, bacterial numbers of 12 biofilms per group were analysed, and all specimens submitted to transversal microradiography.ResultsMineral loss was higher in cavitated dentine than smooth enamel for all biofilms (p < 0.001, t-test). BB12-monospecies biofilms induced significantly less mineral loss than SM in both enamel (p < 0.05) and dentine (p < 0.001). Viable BB12 did not significantly reduce cariogenicity of SM (p > 0.05), whilst heat-inactivated BB12 decreased cariogenicity of SM in dentinal cavities (p < 0.01). Bacterial numbers were higher on dentine than enamel (p < 0.05), but not significantly influenced by biofilm species (p > 0.05).ConclusionsHeat-inactivated BB12 reduced the cariogenicity of SM in dentinal cavities in vitro. Inactivated probiotics might be suitable for caries control.  相似文献   
69.
目的通过对自锁托槽矫治错袷患者定期的牙菌斑染色情况进行比较,探讨系统口腔健康教育对自锁托槽周围牙菌斑的影响。方法将70例即将使用自锁托槽固定矫治器的中学生正畸患者随机分为两组,试验组35例进行系统口腔健康教育并使用牙间隙刷,对照组35例仅进行常规刷牙宣教。在崮定正畸前、治疗6个月、保持期第1个月复诊时对两组正畸患者进行牙菌斑染色,检测菌斑指数并比较结果。结果两组患者治疗前牙菌斑染色指数差异无统计学意义(P〉0.05),但在治疗6个月及保持期1个月全部指标牙位的牙菌斑染色指数差异均有统计学意义(P〈0.05)。结论系统口腔健康宣教并使用牙问隙刷,能提高患者的认知和配合意识,有利于改善自锁托槽矫治错耠患者的口腔卫生状况。  相似文献   
70.
Dental plaque is considered to be a major etiological factor in the development of periodontal disease. Accordingly, the elimination of supra- and sub-gingival plaque and calculus is the cornerstone of periodontal therapy. Dental calculus is mineralized plaque; because it is porous, it can absorb various toxic products that can damage the periodontal tissues. Hence, calculus should be accurately detected and thoroughly removed for adequate periodontal therapy. Many techniques have been used to identify and remove calculus deposits present on the root surface. The purpose of this review was to compile the various methods and their advantages for the detection and removal of calculus.  相似文献   
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