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排序方式: 共有759条查询结果,搜索用时 15 毫秒
721.
722.
Monica C Klempel Surabhi Bhutani Marian Fitzgibbon Sally Freels Krista A Varady 《Nutrition journal》2010,9(1):35
Background
Alternate day modified fasting (ADMF) is an effective strategy for weight loss in obese adults. 相似文献723.
Adrian Quesada Cecilia Granados‐Miralles Alberto Lpez‐Ortega Sergey Erokhin Elisabetta Lottini Javier Pedrosa Alberto Bollero Ana M. Aragn Fernando Rubio‐Marcos Marian Stingaciu Giovanni Bertoni Csar de Julin Fernndez Claudio Sangregorio Jose F. Fernndez Dmitry Berkov Mogens Christensen 《Advanced Electronic Materials》2016,2(4)
Interfacial exchange coupling is known to improve the permanent magnetic performance (i.e., maximal energy product) in composites of magnetically hard and soft particles. The prevailing strategy, employed in a plethora of compositions, consists in maximizing the coupling between the hard and soft phases and optimizing material parameters such as particle size or phase composition. In CoFe2O4–FeCo nanocomposites, it is experimentally shown that interparticle uncoupling in combination with the sizes of the soft phase grains below the single‐domain threshold leads to enhanced magnetic properties at room temperature, while maximizing exchange coupling implies a collapse in coercivity and hence in the maximal energy product. The results are corroborated by micromagnetic calculations and the origin of the exchange‐induced softening is discussed. It is emphasized that engineering interfaces in order to optimize, rather than maximize, the degree of exchange coupling are a necessary requirement to improve the energy product in nanocomposite magnets and to successfully develop advanced rare‐earth‐free permanent magnets. 相似文献
724.
Leszek Zaraska Grzegorz D. Sulka Marian Jasku?a 《Surface & coatings technology》2010,205(7):2432-2437
The through-hole porous anodic aluminum oxide (AAO) membranes were fabricated by a two-step anodization of the aluminum alloy (AA1050) in 0.3 M oxalic acid at 45 V and 20 °C followed by removal of Al and pore opening/widening procedures. The effect of duration of the second anodizing step on the porous oxide layer thickness and the influence of the pore opening time on structural features of as-prepared membranes were studied in detail. The prepared membranes with a thickness of about 60 μm were used as templates for fabrication of dense arrays of Ag, Au, and Sn nanowires with various aspect ratios by a DC electrochemical deposition process. The successful synthesis of metallic nanowires by simple DC electrodeposition of metals inside the pores of AAO templates fabricated from the AA1050 alloy was reported for the first time. The fabrication costs of nanowire arrays can be reduced by about 500 times when AAO templates, prepared from the AA1050 alloy, are used instead of those usually formed from expensive high purity Al. 相似文献
725.
Miller ML Andringa A Turner LT Dalton TP Derkenne S Nebert DW 《Microscopy research and technique》2003,60(5):528-536
Gingival overgrowth is a common health problem caused by genetic and environmental risk factors. Animal models for quantitative histological studies are needed to uncover genetic predisposition and dose-response data that might put individuals at increased risk for gingival disease. Gingival height, thickness, inflammation, and the degree of encroachment of gingiva over the tooth, are clinical measures of overgrowth; most of these parameters can be measured histologically, but in order to quantify gingival coverage of the tooth, the image of the crown must be present. Tooth and bone typically require decalcification for histology; thus, the tooth crown, a critical landmark, is lost. We describe a method for imaging the crown histologically, using impression materials applied to dissected mouse mandibles. Four dental alginates, three polyvinyl siloxanes, and one polyether and gelatin were used. The impression-material/mandibular tissue blocks were processed routinely. Polyvinyl siloxanes were incompatible with embedding resin; alginates, polyether and gelatin could be fixed, decalcified, embedded, and sectioned. Alginates and gelatin could be stained. Success in imaging the tooth crown varied with the preparation, but the alginates, polyether, and gelatin permitted a useful degree of measurement of exposed crown and enamel thickness, along with other morphometric parameters such as thickness of the dentin, lateral mandibular ramus, rete pegs, height of the gingiva, and volume density of vessels and inflammatory cells in the lamina propria. In conclusion, this new application for impression materials allows gingival coverage of tooth crown, as well as numerous other parameters to be measured for comparison with clinical data. 相似文献
726.
Teodora-Irina Adam-Bonci Eduard-Alexandru Bonci Alina-Elena Prvu Andrei-Ioan Herdean Augustin Mo Marian Taulescu Andrei Ungur Raluca-Maria Pop Corina Bocan Alexandru Irimie 《International journal of molecular sciences》2021,22(13)
Asthma oxidative stress disturbances seem to enable supplementary proinflammatory pathways, thus contributing to disease development and severity. The current study analyzed the impact of two types of oral vitamin D (VD) supplementation regimens on the redox balance using a murine model of acute ovalbumin-induced (OVA-induced) asthmatic inflammation. The experimental prevention group received a long-term daily dose of 50 µg/kg (total dose of 1300 µg/kg), whereas the rescue group underwent a short-term daily dose of 100 µg/kg (total dose of 400 µg/kg). The following oxidative stress parameters were analyzed in serum, bronchoalveolar lavage fluid (BALF) and lung tissue homogenate (LTH): total oxidative status, total antioxidant response, oxidative stress index, malondialdehyde and total thiols. Results showed that VD significantly reduced oxidative forces and increased the antioxidant capacity in the serum and LTH of treated mice. There was no statistically significant difference between the two types of VD supplementation. VD also exhibited an anti-inflammatory effect in all treated mice, reducing nitric oxide formation in serum and the expression of nuclear factor kappa B p65 in the lung. In conclusion, VD supplementation seems to exhibit a protective role in oxidative stress processes related to OVA-induced acute airway inflammation. 相似文献
727.
Bibi S. van Thiel Janette van der Linden Yanto Ridwan Ingrid M. Garrelds Marcel Vermeij Marian C. Clahsen-van Groningen Fatimunnisa Qadri Natalia Alenina Michael Bader Anton J. M. Roks A. H. Jan Danser Jeroen Essers Ingrid van der Pluijm 《International journal of molecular sciences》2021,22(22)
Changes in the renin–angiotensin system, known for its critical role in the regulation of blood pressure and sodium homeostasis, may contribute to aging and age-related diseases. While the renin–angiotensin system is suppressed during aging, little is known about its regulation and activity within tissues. However, this knowledge is required to successively treat or prevent renal disease in the elderly. Ercc1 is involved in important DNA repair pathways, and when mutated causes accelerated aging phenotypes in humans and mice. In this study, we hypothesized that unrepaired DNA damage contributes to accelerated kidney failure. We tested the use of the renin-activatable near-infrared fluorescent probe ReninSense680™ in progeroid Ercc1d/− mice and compared renin activity levels in vivo to wild-type mice. First, we validated the specificity of the probe by detecting increased intrarenal activity after losartan treatment and the virtual absence of fluorescence in renin knock-out mice. Second, age-related kidney pathology, tubular anisokaryosis, glomerulosclerosis and increased apoptosis were confirmed in the kidneys of 24-week-old Ercc1d/− mice, while initial renal development was normal. Next, we examined the in vivo renin activity in these Ercc1d/− mice. Interestingly, increased intrarenal renin activity was detected by ReninSense in Ercc1d/− compared to WT mice, while their plasma renin concentrations were lower. Hence, this study demonstrates that intrarenal RAS activity does not necessarily run in parallel with circulating renin in the aging mouse. In addition, our study supports the use of this probe for longitudinal imaging of altered RAS signaling in aging. 相似文献
728.
Maria Kovalska Eva Baranovicova Dagmar Kalenska Anna Tomascova Marian Adamkov Libusa Kovalska Jan Lehotsky 《International journal of molecular sciences》2021,22(9)
L-methionine, an essential amino acid, plays a critical role in cell physiology. High intake and/or dysregulation in methionine (Met) metabolism results in accumulation of its intermediate(s) or breakdown products in plasma, including homocysteine (Hcy). High level of Hcy in plasma, hyperhomocysteinemia (hHcy), is considered to be an independent risk factor for cerebrovascular diseases, stroke and dementias. To evoke a mild hHcy in adult male Wistar rats we used an enriched Met diet at a dose of 2 g/kg of animal weight/day in duration of 4 weeks. The study contributes to the exploration of the impact of Met enriched diet inducing mild hHcy on nervous tissue by detecting the histo-morphological, metabolomic and behavioural alterations. We found an altered plasma metabolomic profile, modified spatial and learning memory acquisition as well as remarkable histo-morphological changes such as a decrease in neurons’ vitality, alterations in the morphology of neurons in the selective vulnerable hippocampal CA 1 area of animals treated with Met enriched diet. Results of these approaches suggest that the mild hHcy alters plasma metabolome and behavioural and histo-morphological patterns in rats, likely due to the potential Met induced changes in “methylation index” of hippocampal brain area, which eventually aggravates the noxious effect of high methionine intake. 相似文献
729.
730.