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51.
《Biomarkers》2013,18(1):23-29
Pulmonary arteriovenous malformations (PAVMs), which can lead to life-threatening bleeding and other complications, have been reported to occur in 30–50% of patients with hereditary hemorrhagic telangiectasia (HHT). Circulating microRNAs (miRNAs) have emerged as new biomarkers for human diseases. This study was conducted to explore circulating miRNAs as biomarkers for the screening of HHT patients with PAVMs. MicroRNA array analysis revealed eight altered circulating miRNAs in patients with PAVMs. Real time RT-PCR showed that the levels of circulating miR-210 were significantly elevated in HHT patients with PAVMs but not changed in patients without PAVMs as compared with healthy controls. Circulating miR-210 therefore may be used as a new and sensitive biomarker for the screening of patients with HHT for clinically significant PAVMs.  相似文献   
52.
《Biomarkers》2013,18(5):436-445
Background: Acute kidney injury (AKI) following cardiac surgery with cardiopulmonary bypass (CPB) causes increased morbidity and mortality.

Objective: To evaluate the plasma profile of biomarkers potentially involved in AKI development following CPB.

Methods: In a nested case–control study, plasma levels of 27 biomarkers in 11 AKI cases were compared with 25 controls.

Results: Pre-CPB, plasma levels of epidermal growth factor and macrophage inflammatory protein-1β, 2?h following CPB, soluble vascular cell adhesion molecule-1 (sVCAM-1), fractalkine and macrophage inflammatory protein-1α, and at later time points, sVCAM-1 and interleukin-6 were associated with AKI.

Conclusion: Biomarkers associated with AKI following CPB may merit further study.  相似文献   
53.
Cancer risk in parents may be related to congenital malformations (CMs) in their children if they share genetic susceptibility or environmental exposure that may be teratogenic and carcinogenic. We conducted a population‐based cohort study based on Danish register data. We identified 795,607 mothers and 781,424 fathers who had all their children between 1977 and 2007 in Denmark. Information on CM was obtained from the Danish Hospital Registry and information on cancer was obtained from the Danish Cancer Registry. Parents were followed from the birth of their first child until the diagnosis of cancer, death, emigration, or December 31, 2007. We used Cox regression models to estimate hazard ratios (HRs) for cancer including cancer in specific organs in mothers and fathers. Overall, 75,701 (9.5%) mothers and 72,724 (9.3%) fathers had at least one child diagnosed with CMs within the first year of life. Neither mothers (HR = 1.04; 95% CI: 0.99–1.04) nor fathers (HR = 1.03; 95% CI: 0.98–1.09) who had a child with a CM had a higher overall risk of cancer. Mothers (HR = 0.76, 95% CI: 0.58–1.00) or fathers (HR = 0.89, 95% CI: 0.66–1.19) who had a child with a chromosomal malformation had a lower overall cancer risk. The findings also showed a higher risk for some specific types of cancer in parents who had children with a CM in the specific system. Some, or perhaps all, of these findings may be due to chance caused by multiple comparisons. We present all results on paper or online to provide clues for further research and to avoid publication bias.  相似文献   
54.
Malformation is arguably the most crucial disease of mango (Mangifera indica L.) at present. It is receiving great attention not only because of its widespread and destructive nature but also because of its etiology and control is not absolutely understood. Recently, Fusarium mangiferae is found to be associated with mango malformation disease. There are indications that stress ethylene production could be involved in the disease. Here we have shown the first direct evidence of production of ethylene in pure culture of F. mangiferae obtained from mango. The study also revealed that all the isolates dissected from mango acquire morphological features of F. mangiferae showing most similarity to the features of species with accepted standard features. The isolates of F. mangiferae from mango were observed to produce ethylene in significant amounts, ranging from 9.28–13.66 n mol/g dry wt/day. The findings presented here suggest that F. mangiferae could contribute to the malformation of mango by producing ethylene and probably stimulating stress ethylene production in malformed tissue of mango. Ethylene might be produced through 2-oxoglutarate-dependent oxygenase-type ethylene-forming-enzyme (EFE) pathway in Fusarium sp, which needs to be investigated.  相似文献   
55.

Purpose

Although rare, children and young adults can suffer from significant cardiac arrhythmia, especially in the context of congenital malformations and after cardiac surgery.

Methods

A total of 62 patients (32 female, median age 20 years) underwent an invasive electrophysiology study between 2008–2011: half had normal cardiac anatomy, whereas the remaining patients had various types of congenital heart disease. All patients were treated using either conventional techniques (CVN) or remote magnetic navigation (RMN).

Results

Patients treated with the RMN system differed substantially from patients in the CVN group with respect to presence of congenital heart disease (67 % vs. 37 %), previous cardiac surgery (59 % vs. 20 %) or failed previous conventional ablation (22 % vs. 9 %), respectively. Although these more complex arrhythmias resulted in longer median procedure duration (180 vs. 130 min, p = 0.034), the median overall fluoroscopy exposure in the RMN group was significantly lower (4.1 vs. 5.2 min, p = 0.020). Clinical outcome was comparable in both groups without complications caused by the ablation.

Conclusions

Catheter ablation using remote magnetic navigation is safe and feasible in children and young adults and is especially valuable in patients with abnormal cardiac morphologies. RMN resulted in significantly lower radiation exposure compared with the conventional technique.  相似文献   
56.
Predicting fluid responsiveness, the response of stroke volume to fluid loading, is a relatively novel concept that aims to optimise circulation, and as such organ perfusion, while avoiding futile and potentially deleterious fluid administrations in critically ill patients. Dynamic parameters have shown to be superior in predicting the response to fluid loading compared with static cardiac filling pressures. However, in routine clinical practice the conditions necessary for dynamic parameters to predict fluid responsiveness are frequently not met. Passive leg raising as a means to alter biventricular preload in combination with subsequent measurement of the change in stroke volume can provide a fast and accurate way to guide fluid management in a broad population of critically ill patients.  相似文献   
57.
A wide range of evidence implicates the brain as playing a significant role in ventricular arrhythmias and sudden cardiac death. The mechanism is thought to involve the intermediary of the autonomic nervous system. Here we briefly consider possible mechanisms by which central neural processing may modulate the myocardial electrophysiology and hence the arrhythmia substrate.  相似文献   
58.
目的:低温在许多小鼠心跳骤停后复苏模型的研究中被证实是有效的。心跳骤停后释放的氧自由基是产生继发性损伤的一个重要机制。本研究旨在探索心跳骤停期间应用中度低温对复苏后抗氧化物酶活性的影响。方法:用氯化钾诱导8min心跳骤停。此实验分为常温心跳骤停组(NCA)、低温心跳骤停组(HCA)TL对照组。HCA组在心跳骤停5min后开始降温使核心温度维持在(30.0±1.0)℃。应用胸部按压和肾上腺素来复苏。在心跳骤停两组各选择三个时间点:复苏后1h、4h和24h。测量超氧化物歧化酶(SOD)和过氧化氢酶(CAT)在心脏和肝脏的活性。结果:实验动物在HCA组比常NCA组生存率高。HCA组比NCA组复苏时间明显延长。与NCA组相比,HCA组复苏后24h的SOD活性在肝脏表达明显降低。与NCA组相比,HCA组复苏后4h的CAT活性在肝脏表达显著增高。结论:在心跳骤停过程中,与正常体温相比,应用中度低温能够提高生存率。与正常体温相比较,在心跳骤停中期间应用中度低温不影响心脏的SOD与CAT活性,应用中度低温在肝脏可延迟性抑制SOD的活性并且短暂提高CAT活性。  相似文献   
59.
目的:探讨左室主动固定电极在心脏再同步化治疗(cardiac resynchronization therapy,CRT)中的作用并总结其临床经验。方法:收集2008年1月至2013年1月由梅州I市人民医院心内科植入CRT的患者,共56例(男34例,女22例)。根据植入冠状窦电极的不同,分为左室主动固定电极组(17例)和被动电极组(39例),观察和比较两组的手术时间、透视时间和造影剂用量。结果:左室主动固定电极组的手术时间[(61±36)minvs(143+61)min,P=0.035]和透视时间[(10±5)minvs(45+11)min,P=0.042]均较被动电极组显著缩短,而造影剂用量[(36±20)mlvs(87±46)ml,P=0.041]也较被动电极组明显减少。结论:左室主动固定电极用于心脏再同步化治疗可明显缩短手术时间,降低造影剂用量,使患者和术者均获益。  相似文献   
60.
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