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11.
Vasiliki Tsigkou Gerasimos Siasos Evangelos Oikonomou Evanthia Bletsa Manolis Vavuranakis Dimitris Tousoulis 《World Journal of Virology》2022,11(4):216
Coronavirus disease 2019 (COVID-19) is associated with poor cardiovascular outcomes in patients with heart failure (HF) of all categories of ejection fraction (EF), but mainly in patients with HF with reduced EF. Moreover, cardiac transplant patients exhibit worse cardiovascular prognosis, high mortality, and more admissions to the intensive care unit. In general, COVID-19 seems to de-teriorate the clinical status of HF and favors the development of acute respiratory distress syndrome and multiorgan failure, especially in the presence of cardiovascular comorbidities such as diabetes mellitus, kidney dysfunction, and older age. COVID-19 may induce new-onset HF with complex mechanisms that involve myocardial injury. Indeed, myocardial injury comprises a large category of detrimental effects for the myocardium, such as myocardial infarction type 1 or type 2, Takotsubo cardiomyopathy, microvascular dysfunction and myocarditis, which are not easily distinguished by HF. The pathophysiologic mechanisms mainly involve direct myocardial damage by severe acute respiratory syndrome coronavirus 2, cytokine storm, hypercoagulation, inflammation, and endothelial dysfunction. The proper management of patients with COVID-19 involves careful patient evaluation and ongoing monitoring for complications such as HF. 相似文献
12.
Enzymatic mild acidolysis lignins (EMAL) isolated from different species of softwood and Eucalyptus globulus were submitted to comparative analysis that included thioacidolysis, derivatization followed by reductive cleavage (DFRC), and DFRC followed by quantitative (31)P NMR (DFRC/(31)P NMR). While gas chromatography (GC) was used to determine the monomer yields from both thioacidolysis and DFRC, (31)P NMR studies quantified the various phenolic hydroxy groups released by DFRC. The monomer yields from thioacidolysis and DFRC were substantially different, with thioacidolysis resulting in higher yields. In contrast, an excellent agreement was obtained in the total number of beta-aryl ether structures determined by thioacidolysis and DFRC/(31)P NMR, indicating that the combination of DFRC with quantitative (31)P NMR overcomes, at least in part, the limitations presented by the DFRC method. Both thioacidolysis and DFRC/(31)P NMR were further used to better understand the lignin isolation process from wood. The results show that mild rotary ball milling minimizes, but does not prevent, the degradation of beta-O-4 structures during the early stages of wood pulverization. The extent of such degradation was found to be higher for E. globulus than for a variety of softwoods examined. Furthermore, the structures of the EMALs isolated at yields ranging from 20% to 62% were very similar, indicating structural homogeneity in the lignin biopolymer within the secondary wall. 相似文献
13.
Eystratios G. Keramidas Dimitris Maroulis Dimitris K. Iakovidis 《Journal of medical systems》2012,36(3):1271-1281
In this paper, we present a computer-aided-diagnosis (CAD) system prototype, named TND (Thyroid Nodule Detector), for the detection of nodular tissue in ultrasound (US) thyroid images and videos acquired during thyroid US examinations. The proposed system incorporates an original methodology that involves a novel algorithm for automatic definition of the boundaries of the thyroid gland, and a novel approach for the extraction of noise resilient image features effectively representing the textural and the echogenic properties of the thyroid tissue. Through extensive experimental evaluation on real thyroid US data, its accuracy in thyroid nodule detection has been estimated to exceed 95%. These results attest to the feasibility of the clinical application of TND, for the provision of a second more objective opinion to the radiologists by exploiting image evidences. 相似文献
14.
Dimitris Voudouris Saritha Radhakrishnan Vassilia Hatzitaki Eli Brenner 《Gait & posture》2013,37(3):477-482
We examined whether challenging upright stance influences the execution of a grasping task. Participants reached to grasp a small sphere while standing either on a stable surface or on foam. Before reaching for the sphere, participants exhibited more body sway and greater fluctuations in the centre of pressure when standing on foam. While reaching for the sphere, the overall body posture changed less when standing on foam than when standing on the stable surface. The digits’ and wrist's movements towards the sphere were no different when standing on foam than when standing on the stable surface. Presumably, the redundancy in the way movements can be performed is exploited to choose the most suitable changes in joint angles to achieve the desired movements of the digits under the prevailing conditions. 相似文献
15.
A 60-year-old man with polyarteritis nodosa under treatment presented with syncope. Echocardiography demonstrated hypertrophic obstructive cardiomyopathy; coronary arteriography revealed normal findings, and Holter monitor showed episodes of non-sustained ventricular tachycardia. This is the first report of hypertrophic obstructive cardiomyopathy developing in a patient with polyarteritis nodosa. Further studies should examine whether a true association exists.Abbreviations ESR
Erythrocyte sedimentation rate
- PAN
Polyarteritis nodosa 相似文献
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18.
Dimitris Tousoulis Charalambos Antoniades Christodoulos Stefanadis 《Journal of the American College of Cardiology》2006,47(6):1237; author reply 1237-1237; author reply 1238
19.
Petros Thomakos Olga Kepaptsoglou Asteris Korantzis Anastasia Trouva Ioannis Sklavounos Dimitris Trouvas Nadia Taraoune Carol Barreto Christos Sp. Zoupas 《Journal of diabetes and its complications》2021,35(6):107914
BackgroundIn Vitro Fertilization (IVF) is increasingly becoming a necessary mode of reproduction. This high risk group is prone to Gestational Diabetes Mellitus (GDM) which further exposes these pregnancies to an increased risk of adverse outcomes. In light of the limited data in the current literature, further investigation is needed regarding the time of GDM diagnosis in IVF pregnancies as well as the outcome of IVF pregnancies complicated by GDM.MethodsIn this three center pilot cross sectional study, the data of 101 singleton IVF pregnancies complicated by GDM were analyzed. Prompt GDM diagnosis in IVF pregnancies was accomplished by self-blood glucose monitoring (SMBG) from the first antenatal visit and confirmed by an OGTT. To evaluate pregnancy outcome, maternal and fetal complications in the 101 GDM IVF group was compared to 101 IVF as well as 101 spontaneous conceptions (SC). The three groups were matched by age. The effect of demographic and glycemic parameters on the outcome of GDM IVF pregnancies was investigated.ResultsGDM diagnosis was made before the 24th week in 37.6% of the GDM IVF group. The week of delivery was earlier for the GDM IVF group (37 ± 1.7) relative to the IVF (37.9 ± 0.9, p < 0.001) and the SC group (38.1 ± 0.8, p < 0.001). GDM IVF pregnancies exhibited greater preeclampsia rates and 84.8% underwent caesarian section. No significant difference regarding LGA and SGA birth weights was found. Complications of GDM IVF pregnancies were associated with the 1-h postprandial BG (r = 0.267, p = 0.007).ConclusionGDM screening in IVF pregnancies may be considered earlier than the 24th week. IVF pregnancies affected by GDM are prone to increased maternal and fetal complications which are associated with 1-h postprandial BG. 相似文献
20.
Euthyroid Sick Syndrome and the Role of Cytokines 总被引:5,自引:0,他引:5
Papanicolaou DA 《Reviews in endocrine & metabolic disorders》2000,1(1-2):43-48