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91.
Mineral trioxide aggregate enriched with iron disulfide nanostructures: an evaluation of their physical and biological properties 下载免费PDF全文
Liliana Argueta‐Figueroa José J. Delgado‐García René García‐Contreras Omar Martínez‐Alvarez José Santos‐Cruz Carlos Oliva‐Martínez Laura S. Acosta‐Torres Javier de la Fuente‐Hernández Ma C. Arenas‐Arrocena 《European journal of oral sciences》2018,126(3):234-243
The purpose of this study was to characterize mineral trioxide aggregates (MTA) enriched with iron disulfide (FeS2) nanostructures at different concentrations, and to investigate their storage modulus, radiopacity, setting time, pH, cytotoxicity, and antimicrobial activity. Iron disulfide nanostructures [with particle size of 0.357 ± 0.156 μm (mean ± SD)] at weight ratios of 0.2, 0.4, 0.6, 0.8, and 1.0 wt% were added to white MTA (wMTA). The radiopacity, rheological properties, setting time, and pH, as well as the cytotoxicity (assessed using the MTT assay) and antibacterial activity (assessed using the broth microdilution test) were determined for MTA/FeS2 nanostructures. The nanostructures did not modify the radiopacity values of wMTA (~6 mm of aluminium); however, they reduced the setting time from 18.2 ± 3.20 min to 13.7 ± 1.8 min, and the storage modulus was indicative of a good stiffness. Whereas the wMTA/FeS2 nanostructures did not induce cytotoxicity when in contact with human pulp cells (HPCs) and human gingival fibroblasts (HGFs), they showed bacteriostatic activity against Staphylococcus aureus, Escherichia coli, and Enterococcus faecalis. Adding FeS2 nanostructures to MTA might be an option for improving the root canal sealing and antibacterial effects of wMTA in endodontic treatments. 相似文献
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Assessment of cardiac volumes using an isotropic whole‐heart dual cardiac phase sequence in pediatric patients 下载免费PDF全文
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Assessment of global left ventricular excursion using three‐dimensional dobutamine stress echocardiography to identify significant coronary artery disease 下载免费PDF全文
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Marwa Mekki Andrew D. Delgado Adam Fry David Putrino Vincent Huang 《Neurotherapeutics》2018,15(3):604-617
Mobility after spinal cord injury (SCI) is among the top goals of recovery and improvement in quality of life. Those with tetraplegia rank hand function as the most important area of recovery in their lives, and those with paraplegia, walking. Without hand function, emphasis in rehabilitation is placed on accessing one’s environment through technology. However, there is still much reliance on caretakers for many activities of daily living. For those with paraplegia, if incomplete, orthoses exist to augment walking function, but they require a significant amount of baseline strength and significant energy expenditure to use. Options for those with motor complete paraplegia have traditionally been limited to the wheelchair. While wheelchairs provide a modified level of independence, wheelchair users continue to face difficulties in access and mobility. In the past decade, research in SCI rehabilitation has expanded to include external motorized or robotic devices that initiate or augment movement. These robotic devices are used with 2 goals: to enhance recovery through repetitive, functional movement and increased neural plasticity and to act as a mobility aid beyond orthoses and wheelchairs. In addition, lower extremity exoskeletons have been shown to provide benefits to the secondary medical conditions after SCI such as pain, spasticity, decreased bone density, and neurogenic bowel. In this review, we discuss advances in robot-guided rehabilitation after SCI for the upper and lower extremities, as well as potential adjuncts to robotics. 相似文献
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Rafael Arcesio Delgado‐Ruiz Jose Luis Calvo‐Guirado Georgios E. Romanos 《Periodontology 2000》2019,81(1):179-193
The occlusal forces and their influence on the initiation of peri‐implant bone loss or their relationship with peri‐implantitis have created discussion during the past 30 years given the discrepancies observed in clinical, animal, and finite element analysis studies. Beyond these contradictions, in the case of an osseointegrated implant, the occlusal forces can influence the implant‐bone interface and the cells responsible for the bone remodeling in different ways that may result in the maintenance or loss of the osseointegration. This comprehensive review focuses on the information available about the forces transmitted through the implant‐crown system to the implant‐bone interface and the mechano‐transduction phenomena responsible for the bone cells’ behavior and their interactions. Knowledge of the basic molecular biology of the peri‐implant bone would help clinicians to understand the complex phenomenon of occlusal forces and their effects on the implant‐bone interface, and would allow better control of the negative effects of mechanical stresses, leading to therapy with fewer risks and complications. 相似文献
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Marginal bone loss evaluation around immediate non‐occlusal microthreaded implants placed in fresh extraction sockets in the maxilla: a 3‐year study 下载免费PDF全文