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81.
Ekaterina A Polyakova Evgeny N Mikhaylov Dmitry L Sonin Yuri V Cheburkin Mikhail M Galagudza 《老年心脏病学杂志》2021,18(1):47-66
Heart failure is common in adult population,accounting for substantial morbidity and mortality worldwide.The main risk factors for heart failure are coronary artery disease,hypertension,obesity,diabetes mellitus,chronic pulmonary diseases,family history of cardiovascular diseases,cardiotoxic therapy.The main factor associated with poor outcome of these patients is constant progression of heart failure.In the current review we present evidence on the role of established and candidate neurohumoral biomarkers for heart failure progression management and diagnostics.A growing number of biomarkers have been proposed as potentially useful in heart failure patients,but not one of them still resembles the characteristics of the"ideal biomarker."A single marker will hardly perform well for screening,diagnostic,prognostic,and therapeutic management purposes.Moreover,the pathophysiological and clinical significance of biomarkers may depend on the presentation,stage,and severity of the disease.The authors cover main classification of heart failure phenotypes,based on the measurement of left ventricular ejection fraction,including heart failure with preserved ejection fraction,heart failure with reduced ejection fraction,and the recently proposed category heart failure with mid-range ejection fraction.One could envisage specific sets of biomarker with different performances in heart failure progression with different left ventricular ejection fraction especially as concerns prediction of the future course of the disease and of left ventricular adverse/reverse remodeling.This article is intended to provide an overview of basic and additional mechanisms of heart failure progression will contribute to a more comprehensive knowledge of the disease pathogenesis. 相似文献
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83.
Dmitry Olegovich Bokov Mustafa Z. Mahmoud Gunawan Widjaja Wanich Suksatan Supat Chupradit Usama S. Altimari Hussein Ali Hussein Yasser Fakri Mustafa Milad kazemnejadi 《RSC advances》2022,12(18):10933
A reductive filter paper for selective nitro reduction has been prepared by modification of a pristine cellulose filter paper by Pd/C nanoparticles, as a portable catalyst. The reaction was performed in two different set-ups including (i) filtration and (ii) sealed systems, in the presence of ammonium formate and ex situ generated hydrogen gas reducing agents, respectively. In the sealed system in the presence of H2 gas, the halogenated nitroarenes were completely reduced, while in the filtration system, different derivatives of the nitroarenes were selectively reduced to aryl amines. In both systems, the reduction of nitroarenes to aryl amines was performed with high efficiency and selectivity, comparable to a heterogeneous system. Reaction parameters were comprehensively designed using Design Expert software and then studied. The properties of the catalytic filter paper were studied in detail from the points of view of swellability, shrinkage, reusability, and stability against acidic, alkaline, and oxidative reagents.A novel and efficient catalytic filtration has been developed for the selective reduction of nitro compounds on a Pd/C-doped cellulose filter paper. 相似文献
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85.
Vetrova Marina V. Cheng Debbie M. Bendiks Sally Gnatienko Natalia Lloyd-Travaglini Christine Jiang Wenqing Luoma Jason Blokhina Elena Krupitsky Evgeny Lioznov Dmitry Ekstrand Maria L. Raj Anita Samet Jeffrey H. Lunze Karsten 《AIDS and behavior》2021,25(9):2815-2826
AIDS and Behavior - Little is known about the intersection of HIV stigma and substance use stigma. Using data from 188 HIV-positive people who inject drugs (PWID) in Russia, we examined the... 相似文献
86.
Hydrogen‐Bonding Effects for the C–ON Bond Homolysis and Reformation Reactions of Alkoxyamines 下载免费PDF全文
Elena G. Bagryanskaya Paul Brémond Teddy Butscher Sylvain R. A. Marque Dmitry Parkhomenko Valérie Roubaud Didier Siri Stéphane Viel 《Macromolecular chemistry and physics.》2015,216(5):475-488
N‐(2‐methylpropyl)‐N‐(1‐diethylphosphono‐2,2‐dimethylpropyl)‐O‐(2‐carboxyprop‐2‐yl) hydroxylamine (BlocBuilder MA) is, among the commercially available alkoxyamines, one of the most efficient for nitroxide‐mediated polymerization (NMP). However, recent results have shown that it does not perform well for the NMP of isoprene. The occurrence of intramolecular hydrogen bonding (IHB) between the carboxylic function and the diethoxyphosphoryl group has been proposed as the reason for its low efficiency. In this article, the presence of this IHB is confirmed using IR, 31P NMR, 31P‐1H HOESY, and DFT calculation results. The solvent effect on this IHB and consequently on kd values is also investigated. However, combining kinetic analysis and rate measurements in various solvents, the influence of this IHB on the C? ON bond homolysis and reformation in alkoxyamine is shown to be very weak.
87.
Tiffany C. Ho Boris Gutman Elena Pozzi Hans J. Grabe Norbert Hosten Katharina Wittfeld Henry Vlzke Bernhard Baune Udo Dannlowski Katharina Frster Dominik Grotegerd Ronny Redlich Andreas Jansen Tilo Kircher Axel Krug Susanne Meinert Igor Nenadic Nils Opel Richard Dinga Dick J. Veltman Knut Schnell Ilya Veer Henrik Walter Ian H. Gotlib Matthew D. Sacchet Andr Aleman Nynke A. Groenewold Dan J. Stein Meng Li Martin Walter Christopher R. K. Ching Neda Jahanshad Anjanibhargavi Ragothaman Dmitry Isaev Artemis Zavaliangos-Petropulu Paul M. Thompson Philipp G. Smann Lianne Schmaal 《Human brain mapping》2022,43(1):341-351
Alterations in regional subcortical brain volumes have been investigated as part of the efforts of an international consortium, ENIGMA, to identify reliable neural correlates of major depressive disorder (MDD). Given that subcortical structures are comprised of distinct subfields, we sought to build significantly from prior work by precisely mapping localized MDD-related differences in subcortical regions using shape analysis. In this meta-analysis of subcortical shape from the ENIGMA-MDD working group, we compared 1,781 patients with MDD and 2,953 healthy controls (CTL) on individual measures of shape metrics (thickness and surface area) on the surface of seven bilateral subcortical structures: nucleus accumbens, amygdala, caudate, hippocampus, pallidum, putamen, and thalamus. Harmonized data processing and statistical analyses were conducted locally at each site, and findings were aggregated by meta-analysis. Relative to CTL, patients with adolescent-onset MDD (≤ 21 years) had lower thickness and surface area of the subiculum, cornu ammonis (CA) 1 of the hippocampus and basolateral amygdala (Cohen's d = ?0.164 to ?0.180). Relative to first-episode MDD, recurrent MDD patients had lower thickness and surface area in the CA1 of the hippocampus and the basolateral amygdala (Cohen's d = ?0.173 to ?0.184). Our results suggest that previously reported MDD-associated volumetric differences may be localized to specific subfields of these structures that have been shown to be sensitive to the effects of stress, with important implications for mapping treatments to patients based on specific neural targets and key clinical features. 相似文献
88.
Martin E. Gosnell Dmitry M. Polikarpov Ewa M. Goldys Andrei V. Zvyagin David A. Gillatt 《Urologic oncology》2018,36(1):8.e9-8.e15
Objectives
One of the most reliable methods for diagnosing bladder cancer is cystoscopy. Depending on the findings, this may be followed by a referral to a more experienced urologist or a biopsy and histological analysis of suspicious lesion. In this work, we explore whether computer-assisted triage of cystoscopy findings can identify low-risk lesions and reduce the number of referrals or biopsies, associated complications, and costs, although reducing subjectivity of the procedure and indicating when the risk of a lesion being malignant is minimal.Materials and methods
Cystoscopy images taken during routine clinical patient evaluation and supported by biopsy were interpreted by an expert clinician. They were further subjected to an automated image analysis developed to best capture cancer characteristics. The images were transformed and divided into segments, using a specialised color segmentation system. After the selection of a set of highly informative features, the segments were separated into 4 classes: healthy, veins, inflammation, and cancerous. The images were then classified as healthy and diseased, using a linear discriminant, the naïve Bayes, and the quadratic linear classifiers. Performance of the classifiers was measured by using receiver operation characteristic curves.Results
The classification system developed here, with the quadratic classifier, yielded 50% false-positive rate and zero false-negative rate, which means, that no malignant lesions would be missed by this classifier.Conclusions
Based on criteria used for assessment of cystoscopy images by medical specialists and features that human visual system is less sensitive to, we developed a computer program that carries out automated analysis of cystoscopy images. Our program could be used as a triage to identify patients who do not require referral or further testing. 相似文献89.
Dura to spinal cord distance at different vertebral levels in children and its implications on epidural analgesia: A retrospective MRI‐based study 下载免费PDF全文
90.
Dmitry Popkov 《Strategies in trauma and limb reconstruction (Online)》2018,13(3):191-197
Telescopic rodding has been developed in order to obtain long-lasting osteosynthesis in the growing long bones of children with osteogenesis imperfecta (OI). The major and still unsolved drawback of any telescopic rod or nail design is a lack of rotational stability and, currently, no telescopic system allows immediate weight-bearing. When these problems are associated with insufficient longitudinal bone stability and diminished healing capacity, the result can be unfavourable causing secondary bone fragment displacement, delayed or non-union. This article presents a case report of operative treatment in a 9-year-old girl affected with OI type VIII complicated with postoperative defect and pseudarthrosis of the femur causing functional impairment with loss of walking ability. A combination of intramedullary flexible nailing and minimal external fixation was applied for treatment of femoral defect-pseudarthrosis in a girl of 9 years with OI type VIII. Intramedullary and extramedullary nails with wrapping of titanium nickel mesh subperiosteally provided osteosynthesis and deformity correction of the tibia of a small intramedullary canal diameter. Upright standing and walking with progressive weight-bearing was started 4 days after surgery. There were no septic or vascular complications nor complications related to Ilizarov fixator. Radiographs demonstrated bone union in the femur 46 days after surgery. At the follow-up visit 9 months after fixator removal, clinical alignment remained excellent without any relapse of deformity. Bone remodelling with restitution of medullary canal was noted on lower limb radiographs. The patient was able to stand and walk without pain with an aide or walker. At the follow-up visit 17 months after fixator removal, there was no decrease in achieved functional abilities and the treatment outcome remained satisfactory. Use of an external fixator with intramedullary nailing for treatment of postoperative pseudarthrosis in patient with severe OI (recessive form of OI, type VIII) provides longitudinal, rotational and angular stability. Furthermore, this approach ensured early functional activity and walking with full weight-bearing, both favourable conditions for bone tissue regeneration. The external fixator was applied for a short period and only for additional stability and not for progressive deformity correction or other manipulation. In addition, the combination of intramedullary and extramedullary nailing and subperiosteal titanium nickel mesh seems to be promising for osteosynthesis in the deformity correction of bones with small diameter in children with OI. 相似文献