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采用Mimics对心脏进行三维重构,用3-matic进行模型优化以及模型误差分析,对左心室室壁运动做速度分布假设,基于UDF宏文件对左心室室壁运动编写程序,将血液视为非牛顿流体,采用动网格技术研究不同血压对左心室血液流动的影响。模拟发现当左心室收缩时,压力梯度明显,内部压力减小。当左心室舒张时,内部压力逐渐增高。二尖瓣口处的速率先增大后减小。血压升高,左心室内剪切应力持续增大,极易破坏红细胞结构,产生溶血现象,导致心脏功能紊乱。  相似文献   
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Background and aimsReducing dietary cholesterol is generally acceptable for the prevention of cardiovascular disease (CVD). Eggs are nutrient-dense and common food items across the world, while rich in cholesterol. The potential effects of egg intake on cardiovascular health remain uncertainty and have been under debate in past decades.Methods and resultsA nationwide cohort of 20,688 participants aged 16–110 years without CVD at baseline were derived from the China Family Panel Studies. Egg consumption was assessed by a semi-quantitative food frequency questionnaire. We adopted stratified Cox proportional hazards model with random intercepts for provinces to evaluate associations of egg intake with CVD incidence. During a median follow-up of 6.0 years, we identified 2395 total CVD incidence and mean egg consumption was 3 times/week. Egg intakes were associated lower risks of CVD incidence in the multivariate-adjusted model. Compared with the non-consumers, the corresponding HRs (95% confidence interval) for total CVD events were 0.84 (0.74–0.94) for 1–2 times per week, 0.78 (0.69–0.88) for 3–6/week, and 0.83 (0.72–0.95) for ≥7/week. Similar relationships were found in hypertension. Approximately non-linear relationships were observed between egg consumption with total CVD and hypertension incidence, identifying the lowest risk in 3–6 times/week. Subgroup analyses estimated lower risks of total CVD and hypertension in females only, with significant effect modification by sex (P for interaction = 0.008 and 0.020).ConclusionEgg consumption may be associated with lower risks of CVD incidence among Chinese adults. Our findings could have implications in CVD prevention and might be considered in the development of dietary guidelines.  相似文献   
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The pulmonary alveolocapillary dysplasia (ACD) with pulmonary vein misalignment (PVM) is a rare condition characterized by a congenital anomaly of the development of the pulmonary parenchyma. We present a case of an 8-month-old infant who died quickly from acute respiratory failure complicating an unknown ACD. We also describe its epidemiological characteristics in infants and we discuss the diagnosis's difficulties. In this case, a pulmonary arterial hypertension was decompensated by an infection. A medico-legal autopsy was performed. As for the Histological examination, it showed the features of ACD/PVM.  相似文献   
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【摘要】目的:分析保乳术后放疗患者钛夹动度,并探讨其与乳腺大小、钛夹位置的相关性。方法:随机选取保乳术后放疗患者15例,每周两次锥形束CT。测量乳腺基底面直径(D)和乳高轴(H),以瘤床质心为原点将临床靶区分4个象限。记录各象限内钛夹在左右、腹背、头脚方向动度(MLR、MAP、MSI)以及其与临床靶区最内、最前、最上的距离(DSLR、DSAP、DSSI)。结果:MLR、MAP、MSI分别为(2.2±3.0)、(-1.1±3.6)、(0.8±4.7) mm;系统误差Σ在左、右、腹、背、头、脚分别为1.7、2.2、2.0、2.4、2.9、3.0 mm,随机误差σ分别为2.4、4.0、3.2、4.0、4.7、4.7 mm;靶区对应外放5.9、8.3、7.2、8.8、10.5、10.9 mm。一象限内,当D×H<99.89 cm2,MAP和D×H强相关(r=0.805),MLR、MAP均和DSLR、DSAP、DSSI强正相关(r=0.94, 0.94, 0.91;0.87, 0.91, 0.92),MSI和DSLR、DSAP强正相关(r=0.91, 0.94);四象限内,当D×H<90.71 cm2,MAP和DSLR,MSI和DSAP均强负相关(r=-0.96;-0.95),MLR和DSLR强正相关(r=0.91)。结论:钛夹动度有各向异性,以SI方向外扩最大,并易受乳腺大小、钛夹位置影响。  相似文献   
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PurposeThe purpose of this study was to investigate right atrial and ventricular strain parameters on cardiac magnetic resonance (CMR) in patients with precapillary pulmonary hypertension (PPH) and whether they can aid in the assessment of PPH prognosis.Materials and methodsAdult patients with groups 1 and 4 PPH were invited to participate in the study. Age- and sex-matched healthy volunteers were also recruited as controls. At baseline, patients underwent clinical examination, N-terminal pro-B-type natriuretic peptide measurement and CMR with feature tracking post-processing (CMR-FT). Healthy controls underwent only CMR-FT. The study's primary endpoint was clinical failure, defined as death, hospitalization or demonstrable clinical deterioration during follow-up. Patients who were unable to perform 6-minute walking test due to musculoskeletal disorders were excluded from the study.ResultsThirty-six patients (8 men, 28 women; mean age, 50.6 ± 13.8 [SD] years [range: 18.6–78.5 years]) and 12 healthy control subjects (5 mean, 7 women; mean age, 40.6 ± 13.5 [SD] years [range: 23.1–64.4 years]) were recruited. Right ventricular global longitudinal strain (GLS) was significantly impaired in PPH patients (?20.2 ± 5.3 [SD] % [range: ?28.8 to ?9.1%] vs. ?28.4 ± 3.1% [?33.7 to ?22.7%] respectively, P < 0.001). The right atrial GLS was significantly impaired in PPH compared to healthy controls (?19.9 ± 4.5% [range: ?28.6 to ?3.6%] vs. ?26.5 ± 4.2% [range: ?32.8 to ?15.8%] respectively) (P < 0.001). Clinical failure occurred in 19 (19/36, 53%) of patients. Right ventricular GLS predicted clinical failure most reliably among CMR parameters (?22.6 ± 3.8 [SD] % [range: ?27.6 to ?12.7%] for patients without clinical failure vs. ?18 ± 5.6 [SD] % [range: ?28.8 to ?9.1%] for patients with clinical failure; hazard ratio [HR] = 1.85; P = 0.007; area under the AUC curve = 0.75). Lower absolute right atrial GLS was significantly associated with clinical failure (?22.7 ± 3.0 [SD] % [range: ?28.6 to ?17.7%] for patients without clinical failure vs. ?16.9 ± 5.8 [SD] % [range: ?24.2 to ?3.6%] for patients with clinical failure) (HR = 1.53; P = 0.035).ConclusionCMR feature tracking-derived myocardial strain parameters of both the right atrium and ventricle can assist clinicians in the prognosis of PPH.  相似文献   
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针对现有基于心冲击描记图进行心率检测存在的抗干扰性不足问题,提出一种鲁棒的心率检测模型,首先对原始信号中受干扰的片段进行补偿重构,然后将J峰作为特征波形,通过基于J峰频段的滤波与差分增强处理放大特征,并设计改进的峰值提取算法定位心跳点,进而得到心率估计值。实验结果表明,所用模型对于不同情形下的心冲击描记图信号均表现出良好的适应性,逐拍检测平均覆盖率为98.3%,平均准确率为98.4%。心率输出结果与金标准一致性高,误差范围控制在[±]5%以内,且运算实时性好,可以为临床或家庭保健提供良好的心率检测方案。  相似文献   
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张凌芸 《妇幼护理》2021,1(2):243-245
妊娠期高血压疾病是女性妊娠期间极为常见的一种妊娠并发症,亦为妇产科临床中极为常见的一种病症,该病症可产生 极大的危害性。目前临床主要站在流行病学角度上研究妊娠期高血压疾病,针对该病症的发病诱因、机制等尚未有统一认识形 成。本文主要分析和总结妊娠期高血压疾病的相关危险因素和护理干预措施,以供今后临床作参考。  相似文献   
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