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Evident Effect (evident + effect)

Distribution by Scientific Domains

Medical Sciences	50%

Selected Abstracts

Influence of abutment substrate and ceramic thickness on the colour of heat-pressed ceramic crowns

JOURNAL OF ORAL REHABILITATION, Issue 9 2002
T. NAKAMURA
Summary All-ceramic crowns made of leucite-based heat-pressed ceramics are widely used to restore non-vital teeth in conjunction with various post and core materials. However, as some light passes through the ceramic, the colour of the abutment substrate can negatively affect the final aesthetic appearance of the all-ceramic crown. In this study, we made background specimens simulating gold-alloy cast posts and other simulating porcelain veneered cast posts, overlaid different thickness of heat-pressed ceramic on these background specimens, and measured the shifts in colour. We found that, when the background specimen was a gold alloy, the background colour had an effect on the apparent colour, unless the ceramic was more than 1·6 mm thick. When the background specimen was porcelain veneered, the background colour had no evident effect, even when the ceramic was not very thick. Therefore, when making a restoration using a leucite-based heat-pressed ceramic crown, it is advisable to use tooth-coloured materials such as a porcelain veneered cast post, if you will not be able to make the ceramic more than 1·6 mm thick. [source]

Wettability of Silica Substrates by Silver,Copper Based Brazing Alloys inVacuo

JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 12 2000
Jorge López-Cuevas
The sessile drop method has been used to determine the time dependence of the contact angle at 850°C in vacuo for Ag,28 wt% Cu, Ag,35 wt% Cu,1.5 wt% Ti, and Ag,27 wt% Cu,12 wt% In,2 wt% Ti on vitreous and devitrified fused quartz substrates. Nonwetting behavior (, > 90°) was observed for Ag,28 wt% Cu on both substrates with no evident effect of time at temperature. The silica substrate structure, whether crystalline or amorphous, as well as its surface condition, whether smooth or rough, made no significant difference. In contrast, with Ag,35 wt% Cu,1.5 wt% Ti and Ag,27 wt% Cu,12 wt% In,2 wt% Ti the contact angle continuously decreased with time for both silica substrates, and the structure and surface condition of the substrates had a negligible effect in the case of Ag,27 wt% Cu,12 wt% In,2 wt% Ti, which produced essentially the same contact angles on both silica substrates at a given time of hold at 850°C. The contact angles produced by Ag,35 wt% Cu,1.5 wt% Ti on devitrified fused quartz were consistently higher than those produced on the vitreous substrates, with increasing holding time at 850°C. This is attributable to the presence of extensive cracks in the ,-cristobalite layer at the surface of the devitrified substrates, which obstruct wetting and spreading. These results, when correlated with the wettability of preoxidized silicon carbide by the same alloys reported in previous work, could account for the adverse effect on wetting of the high-temperature silica films formed on the surface of the SiC in that work. [source]

Panax notoginseng (Burk.) effects on fibrinogen and lipid plasma level in rats fed on a high-fat diet

PHYTOTHERAPY RESEARCH, Issue 2 2003
A. F. G. Cicero
Abstract Several studies have shown that notoginsenoides improve diastolic function in hypertensive subjects, induce the fibrinolytic system in in vitro models and act as antiproliferative agents on vessel leiomyocytes. Our aim was to evaluate their effect on fibrinogen and lipid plasma levels compared with a well-known HMGCoA reductase inhibitor. Seventy Wistar male adult rats on a fat-enriched diet were treated orally with P. notoginseng pulverized root (43,mg/kg/day or 86,mg/kg/day; 20 animals per group), fluvastatin (3,mg/kg/day; 20 animals) or physiological saline (5,mL/kg/day; 10 animals). The ten rats on a normocaloric diet were also treated with 5,mL/kg/day of physiological saline. After a 28-day treatment, the rats were killed and their blood analysed with standard procedures. Treatment with 43,mg/kg/day of P. notoginseng or 3,mg/kg/day of fluvastatin showed similar activity in decreasing total cholesterol (,23.70%, ,19.29%, respectively) and triglycerides (,21.59%, ,18.55%). The most evident effect of P. notoginseng was the reduction of fibrinogenaemia in treated rats compared with the control values (,38.10%; p,<,0.001), no dose-relationship being shown in this effect. Moreover, no significant variation in HDL cholesterol and glucose levels was observed nor did relevant behavioural changes occur in association with the root intake. Besides a moderate, non dose-related decrease in the plasma lipid levels, P. notoginseng appeared to induce a significant reduction in the rat fibrinogenaemia. Copyright © 2003 John Wiley & Sons, Ltd. [source]

Comparative proteomic and transcriptional profiling of a bread wheat cultivar and its derived transgenic line overexpressing a low molecular weight glutenin subunit gene in the endosperm

PROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 14 2008
Federico Scossa
Abstract We carried out a parallel transcriptional and proteomic comparison of seeds from a transformed bread wheat line that overexpresses a transgenic low molecular weight glutenin subunit gene relative to the corresponding nontransformed genotype. Proteomic analyses showed that, during seed development, several classes of endosperm proteins were differentially accumulated in the transformed endosperm. As a result of the strong increase in the amount of the transgenic protein, the endogenous glutenin subunit, all subclasses of gliadins, and metabolic as well as chloroform/methanol soluble proteins were diminished in the transgenic genotype. The differential accumulation detected by proteomic analyses, both in mature and developing seeds, was paralleled by the corresponding changes in transcript levels detected by microarray experiments. Our results suggest that the most evident effect of the strong overexpression of the transgenic glutenin gene consists in a global compensatory response involving a significant decrease in the amounts of polypeptides belonging to the prolamin superfamily. It is likely that such compensation is a consequence of the diversion of amino acid reserves and translation machinery to the synthesis of the transgenic glutenin subunit. [source]