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排序方式: 共有7318条查询结果,搜索用时 15 毫秒
81.
Laura Vandoni Ali G?khan Demir Barbara Previtali Nora Lecis Daniele Ugues 《Materials》2012,5(11):2360-2382
In heavy loaded mating components, such as sliders and sliding bearings, guaranteeing the efficiency of lubricant films for long times during severe service conditions is very complicated. In this work, the benefits deriving from the use of fiber laser sources for surface texturing of very thin TiN coatings in severe wear working conditions were demonstrated. Evaluations of the laser textured dimples shape, geometry and density are given. Wear performance of the fiber laser textured surfaces was evaluated in discontinuous oil lubricated conditions with a flat contact. High normal load and low sliding speed were applied. Comparison tests were also performed on commercial TiN and WC/C coatings. In terms of average wear volume and maximum wear depth, Laser Surface Texturing of TiN provided respectively a 70% and a 45% reduction if compared to plain TiN. If compared to WC/C the wear resistance gains were lower but LST TiN maintained such benefits for longer wear runs. SEM analysis also revealed that the laser interaction provided a localized thermal cracking to the TiN coating. However, the sliding action caused very limited and localized coating fragmentation or delamination. 相似文献
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83.
Use of short implants (6 mm) in a single‐tooth replacement: a 5‐year follow‐up prospective randomized controlled multicenter clinical study
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Tatiana L. Fonseca Joao Pedro Werneck-De-Castro Melany Castillo Barbara M.L.C. Bocco Gustavo W. Fernandes Elizabeth A. McAninch Daniele L. Ignacio Caio C.S. Moises Alexandre Ferreira Balázs Gereben Antonio C. Bianco 《Diabetes》2014,63(5):1594-1604
Type 2 deiodinase (D2) converts the prohormone thyroxine (T4) to the metabolically active molecule 3,5,3′-triiodothyronine (T3), but its global inactivation unexpectedly lowers the respiratory exchange rate (respiratory quotient [RQ]) and decreases food intake. Here we used FloxD2 mice to generate systemically euthyroid fat-specific (FAT), astrocyte-specific (ASTRO), or skeletal-muscle-specific (SKM) D2 knockout (D2KO) mice that were monitored continuously. The ASTRO-D2KO mice also exhibited lower diurnal RQ and greater contribution of fatty acid oxidation to energy expenditure, but no differences in food intake were observed. In contrast, the FAT-D2KO mouse exhibited sustained (24 h) increase in RQ values, increased food intake, tolerance to glucose, and sensitivity to insulin, all supporting greater contribution of carbohydrate oxidation to energy expenditure. Furthermore, FAT-D2KO animals that were kept on a high-fat diet for 8 weeks gained more body weight and fat, indicating impaired brown adipose tissue (BAT) thermogenesis and/or inability to oxidize the fat excess. Acclimatization of FAT-D2KO mice at thermoneutrality dissipated both features of this phenotype. Muscle D2 does not seem to play a significant metabolic role given that SKM-D2KO animals exhibited no phenotype. The present findings are unique in that they were obtained in systemically euthyroid animals, revealing that brain D2 plays a dominant albeit indirect role in fatty acid oxidation via its sympathetic control of BAT activity. D2-generated T3 in BAT accelerates fatty acid oxidation and protects against diet-induced obesity. 相似文献
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Emanuele Angelucci Valeria Santini Anna Angela Di Tucci Giulia Quaresmini Carlo Finelli Antonio Volpe Giovanni Quarta Flavia Rivellini Grazia Sanpaolo Daniela Cilloni Flavia Salvi Giovanni Caocci Alfredo Molteni Daniele Vallisa Maria Teresa Voso Susanna Fenu Lorenza Borin Giancarlo Latte Giuliana Alimena Sergio Storti Alfonso Piciocchi Paola Fazi Marco Vignetti Sante Tura 《European journal of haematology》2014,92(6):527-536
88.
Clara Benedetta Conti Mariangela Giunta Daniele Gridavilla Dario Conte Mirella Fraquelli 《Ultrasound in medicine & biology》2017,43(4):725-734
Crohn's disease (CD) is an inflammatory chronic bowel disorder; it can involve the whole gastrointestinal tract, but its localization in the ileum or colon is most common. The reference standard for the diagnosis of CD is ileocolonoscopy with histologic assessment. The reference standard for the detection of any complications is surgery. However, imaging techniques have an important role both in the detection/localization of CD and in the follow-up of CD patients. In the last few years, the technical development of ultrasound equipment, the advent of new technologies such as elastography and mostly the increased expertise of sonographers have boosted the role of bowel ultrasound in assessment of the gastrointestinal tract. In fact, bowel ultrasound is particularly attractive thanks to its widespread availability, non-invasiveness, low cost and good reproducibility, as it can be easily repeated during follow-up. The aim of this article is to provide an extensive overview of the actual role of bowel ultrasound in the detection and follow-up of patients with CD. 相似文献
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