对国内外几种玻璃纤维根管桩的力学性能评价

目的比较国内外4种玻璃纤维根管桩材料的力学性能,为国产玻璃纤维桩的研究和临床运用提供理论依据。方法选取FIBIO GLASSFIBER POST 9支、MATCHPOST 10支、LuxaPost 10支及国产玻璃纤维桩9支,采用三点加载系统测定其弯曲强度及弹性模量,并进行比较和统计分析。结果弯曲强度除MATCHPOST组与LuxaPost组、LuxaPost组与国产桩组无统计学差异外,其他各组间均有统计学差异(P0.05)。弹性模量除MATCHPOST组与LuxaPost组无统计学差异外,其他各组间均有统计学差异(P0.05)。LuxaPost的弯曲强度最大,FIBIO GLASSFIBER POST的弹性模量最低,与牙本质的弹性模量最接近。结论试验采用的4种玻璃纤维桩材料均体现出良好的力学性能,达到临床使用标准。     

Income and race/ethnicity influence dietary fiber intake and vegetable consumption

Grains, fruits, and vegetables are the primary sources of dietary fiber (DF), with the white potato contributing nearly 7% of the DF to the US food supply. The DF composition of the white potato—with or without the skin and regardless of cooking method—compares well with the DF content of other vegetables. Many health benefits, including improved gastrointestinal health, are attributed to greater DF consumption; however, less than 3% of males and females have an adequate intake of DF. Because of this population-wide shortfall, DF is considered to be a nutrient of concern. In this study, using data from the National Health and Nutrition Examination Survey 2009 to 2010, we examined the mean intake of DF across sex, age, race/ethnicity, family income, and poverty threshold. This study shows that mean intake of DF is far below recommendations, with children and adolescents aged 2 to 19 years consuming an average of less than 14 g of DF per day. Adults 20+ years old consume, on average, about 17 g of DF per day, and men consume significantly more DF than women. Non-Hispanic black adults consume significantly less DF compared with other race/ethnic groups. Lower family income and living at less than 131% of poverty were associated with lower DF intakes among adults. Federal and local government policies should encourage consumption of all vegetables, including the white potato, as an important source of DF.     

玻璃纤维桩及Ipse.max全瓷冠联合修复前牙的护理干预

目的探讨玻璃纤维桩及Ipse.max全瓷冠联合修复前牙中的护理体会。方法对60例采用玻璃纤维桩及Ipse.max全瓷冠联合修复前牙的患者,对其修复治疗过程实施有效的干预及修复后的维护指导。结果患者满意度高,修复效果好。结论实施有效的护理干预是玻璃纤维桩及Ipse.max全瓷冠联合修复前牙治疗成功的关键。而且完成修复后的定期维护和对患者的口腔健康教育也是影响最终修复效果的重要因素。     

Optic neuritis: A mechanistic view

Acute demyelinating optic neuritis is a condition of the optic nerves characterized by inflammation, demyelination, and neurodegeneration. Optic neuritis is a relatively common demyelinating event, strongly associated with multiple sclerosis. A number of clinical, radiographic, retinal imaging, and electrophysiologic techniques have provided significant insight into the pathologic and pathophysiologic mechanisms of optic neuritis and its related disorder multiple sclerosis. The development of validated biomarkers within the anterior visual system has paved the way for novel investigations aimed at characterizing the processes of axonal loss and neurodegeneration, neuroprotection, and perhaps even neurorestoration strategies.     

Endovascular laser detachment of platinum alloy microcoils: Principle and initial experimental experience

Abstract

The aim of the investigation was the technical realization and approval of a new method for insertion and detachment of platinum alloy microcoils and other vascular implants via standard microcatheters. Flexible lightconducting fibers, 105 μm in diameter were connected to platinum alloy microcoils. It was examined whether an insertion wire, a lightconducting fiber and a platinum alloy microcoil could be advanced through a Tracker-18 (Target) microcatheter. The detachment of the attached coil from the lightconducting fiber was investigated. Platinum alloy microcoils can be attached to available lightconducting fibers in a reliable and reproduceable manner. Together with the fiber they can be advanced via a Tracker-18 microcatheter. Only extremely tortuous vessels may increase the friction to critical values. A Ho-YAG laser source was used. This allowed the instantaneous detachment of microcoils from laser fibers. In contrast to electrolytical detachment; no foreign substances are released to the blood stream. The detachment does not require waiting time and does not activate thrombus formation. Due to specific technical features, injuries of the vessel wall are avoided. After further miniaturization and adaption of the lightconducting fibers to the required characteristics; I aster detachment may have the potential to replace current methods such as electrolytical and mechanical coil detachment. [Neurol Res 1996; 18: 256–258]     

β-淀粉样蛋白与老年痴呆症发生发展关系研究进展

老年痴呆症足一种常见的进行性神经系统退行性疾病，主要发生于中老年人群，并且其发病率在逐年升高，对AD发病机制的探讨和研究变得尤为重要。在探讨的过程中，出现了很多发病假说，本文主要围绕β-淀粉样蛋白假说介绍其发病机理和最新的研究进展。     

Effects of TRPV1 activation on synaptic excitation in the dentate gyrus of a mouse model of temporal lobe epilepsy

Temporal lobe epilepsy (TLE) is a condition characterized by an imbalance between excitation and inhibition in the temporal lobe. Hallmarks of this change are axon sprouting and accompanying synaptic reorganization in the temporal lobe. Synthetic and endogenous cannabinoids have variable therapeutic potential in treating intractable temporal lobe epilepsy, in part because cannabinoid ligands can bind multiple receptor types. This study utilized in vitro electrophysiological methods to examine the effect of transient receptor potential vanilloid type 1 (TRPV1) activation in dentate gyrus granule cells in a murine model of TLE. Capsaicin, a selective TRPV1 agonist had no measurable effect on overall synaptic input to granule cells in control animals, but significantly enhanced spontaneous and miniature EPSC frequency in mice with TLE. Exogenous application of anandamide, an endogenous cannabinoid that acts at both TRPV1 and cannabinoid type 1 receptors (CB1R), also enhanced glutamate release in the presence of a CB1R antagonist. Anandamide reduced the EPSC frequency when TRPV1 were blocked with capsazepine. Western blot analysis of TRPV1 receptor indicated protein expression was significantly greater in the dentate gyrus of mice with TLE compared with control mice. This study indicates that a prominent cannabinoid agonist can increase excitatory circuit activity in the synaptically reorganized dentate gyrus of mice with TLE by activating TRPV1 receptors, and suggests caution in designing anticonvulsant therapy based on modulating the endocannabinoid system.     

A Fully Coupled Simulation of Planar Deposition Flow and Fiber Orientation in Polymer Composites Additive Manufacturing

Numerical studies for polymer composites deposition additive manufacturing have provided significant insight promoting the rapid development of the technology. However, little of existing literature addresses the complex yet important polymer composite melt flow–fiber orientation coupling during deposition. This paper explores the effect of flow–fiber interaction for polymer deposition of 13 wt.% Carbon Fiber filled Acrylonitrile Butadiene Styrene (CF/ABS) composites through a finite-element-based numerical approach. The molten composite flow in the extrusion die plus a strand of the deposited bead contacting the deposition substrate is modelled using a 2D isothermal and incompressible Newtonian planar flow model, where the material deposition rate is ~110 mm/s simulating a large scale additive manufacturing process. The Folgar–Tucker model associated with the Advani–Tucker orientation tensor approach is adopted for the evaluation of the fiber orientation state, where the orthotropic fitted closure is applied. By comparing the computed results between the uncoupled and fully coupled solutions, it is found that the flow-orientation effects are mostly seen in the nozzle convergence zone and the extrusion-deposition transition zone of the flow domain. Further, the fully coupled fiber orientation solution is highly sensitive to the choice of the fiber–fiber interaction coefficient CI, e.g., assigning CI as 0.01 and 0.001 results in a 23% partial relative difference in the predicted elastic modulus along deposition direction. In addition, Structural properties of deposited CF/ABS beads based on our predicted fiber orientation results show favorable agreements with related experimental studies.     

Associations of multiple unhealthy lifestyle behaviors with overweight/obesity and abdominal obesity among Brazilian adolescents: A country-wide survey

Background and Aims

Physical inactivity, unhealthy diet, smoking and heavy drinking are four key unhealthy lifestyle behaviors (ULB) that may influence body weight and obesity development. More recently, sedentary time has been recognized as another potentially emerging ULB related to obesity. We therefore investigated the association of multiple ULB with overweight/obesity and abdominal obesity among Brazilian adolescents.