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1.
Christelle Boileau Johanne Martel-Pelletier Judith Caron Philippe Msika Georges B Guillou Caroline Baudouin Jean-Pierre Pelletier 《Arthritis research & therapy》2009,11(2):R41-9
Introduction
The aims of this study were, first, to investigate the in vivo effects of treatment with avocado/soybean unsaponifiables on the development of osteoarthritic structural changes in the anterior cruciate ligament dog model and, second, to explore their mode of action. 相似文献2.
Daw-Yang Hwang Stefan Kohl Xueping Fan Asaf Vivante Stefanie Chan Gabriel C. Dworschak Julian Schulz Albertien M. van Eerde Alina C. Hilger Heon Yung Gee Tracie Pennimpede Bernhard G. Herrmann Glenn van de Hoek Kirsten Y. Renkema Christoph Schell Tobias B. Huber Heiko M. Reutter Neveen A. Soliman Natasa Stajic Radovan Bogdanovic Elijah O. Kehinde Richard P. Lifton Velibor Tasic Weining Lu Friedhelm Hildebrandt 《Human genetics》2015,134(8):905-916
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We consider adaptive robust methods for lung cancer that are also dose-reactive, wherein the treatment is modified after each treatment session to account for the dose delivered in prior treatment sessions. Such methods are of interest because they potentially allow for errors in the delivered dose to be corrected as the treatment progresses, thereby ensuring that the tumor receives a sufficient dose at the end of the treatment. We show through a computational study with real lung cancer patient data that while dose reaction is beneficial with respect to the final dose distribution, it may lead to exaggerated daily underdose and overdose relative to non-reactive methods that grows as the treatment progresses. However, by combining dose reaction with a mechanism for updating an estimate of the uncertainty, the magnitude of this growth can be mitigated substantially. The key finding of this paper is that reacting to dose errors – an adaptation strategy that is both simple and intuitively appealing – may backfire and lead to treatments that are clinically unacceptable. 相似文献
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Mickaël Castelain Marie-Pierre Duviau Virginie Oxaran Philippe Schmitz Muriel Cocaign-Bousquet Pascal Loubière 《Biofouling》2016,32(8):911-923
The present work focuses on the role of pili present at the cell surface of Lactococcus lactis in bacterial adhesion to abiotic (hydrophobic polystyrene) and biotic (mucin-coated polystyrene) surfaces. Native pili-displaying strains and isogenic derivatives in which pilins or sortase C structural genes had been modified were used. Surface physico-chemistry, morphology and shear-flow-induced detachment of lactococcal cells were evaluated. The involvement of pili in L. lactis adhesion was clearly demonstrated, irrespective of the surface characteristics (hydrophobic/hydrophilic, presence or not of specific binding sites). The accessory pilin, PilC, and the backbone pilin, PilB, were revealed to play a major role in adhesion, provided that the PilB was present in its polymerized form. Within the population fraction that remained attached to the surface under increasing shear flow, different association behaviors were observed, showing that pili could serve as anchoring sites thus hampering the effect of shear flow on cell orientation and detachment. 相似文献
7.
Gérard Sarazin Jean-Fran cois Gaillard Laurence Philippe Christophe Rabouille 《Hydrobiologia》1995,315(2):95-118
The chemical composition of the pore water from the sediment of a eutrophic lake is dominated by high concentrations of total dissolved CO2 (up to 12 mM), reduced soluble iron (up to 2 mM) and dissolved silica (up to 1 mM). The pH lies within the range of 6.70 ± 0.02; this reflects that the pore water is efficiently buffered by the CO2 acid/base system. This composition is directly related to the main diagenetic reactions which drive the organic matter mineralization i.e. methanogenesis and ferric oxides reduction. Other geochemical processes are of minor importance. A stoichiometric model based on these main reactions allow us: (i) to define a general formula for the organic matter which is close to Redfield's one for the C:N ratio, while the C:P ratio is much higher owing to a probable adsorption of phosphorus onto reactive surfaces of the solid and due to heterotrophic bacterial uptake; (ii) to calculate a global first order kinetic constant which drives the organo-polymers breakdown. Due to the strong influence on the trophic status of the lake caused by an excess of phosphate, special attention is devoted to this species. We show that the sediment-water interface is a source of dissolved phosphate when the hypolimnion is anoxic between May and November. This contribution represents about 17% of the river input and should be taken into account in any attempt toward lake restoration. 相似文献
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9.
Jean-Michel Panoff Bouachanh Thammavongs Jean-Marie Laplace Axel Hartke Philippe Boutibonnes Yanick Auffray 《Cryobiology》1995,32(6)
The physiology of the cold-shock response in Lactococcus lactis subsp. lactis IL1403 at a subzero temperature, and cold-induced adaptation to heat shock, were investigated. Preincubation of cells at 8°C led to the development of cryotolerance, i.e., an enhanced capacity to survive exposure to freezing temperature (-20°C). Pretreatment with chemicals considered to be chaotropic agents did not induce cryotolerance or, in contrast, led to a decrease in survival capacity at -20°C. Interestingly, preincubation at 8°C led also to thermololerance to a 52°C challenge, but preincubation of cells at 42°C for 30 min did not improve their capacity to survive freezing-thawing exposure. These results demonstrate that cold- and heat-shock responses are physiologically linked by a complex relation. Furthermore, food processing at low temperature before subzero or heat treatment may need to be reconsidered. 相似文献
10.
Stephan Francke Karine Clement Christian Dina Hiroshi Inoue Philip Behn Vincent Vatin Arnaud Basdevant Bernard Guy-Grand M. Alan Permutt Philippe Froguel J. Hager 《Human genetics》1997,100(5-6):491-496
Family studies have shown that in some populations up to 75% of the variation of body mass index can be explained by genetic
factors. However, in humans, no major obesity gene has been identified to date. In contrast, there are a number of genetically
well defined animal models for obesity. In two of those models (ob/ob and db/db), defects in the same pathway are responsible
for obesity. Recently, some evidence has been found for the OB gene also being involved in human obesity. In this study we
investigated the potential role of the OB receptor (OBR) in the etiology of massive obesity in humans using familial linkage
analyses and case-control association studies. The typing of two microsatellite markers (D1S198 and D1S209), flanking the
OBR gene, in 256 sib pairs showed no evidence for linkage with obesity. In order to be able to detect small gene effects,
association studies with a 3′-UTR insertion/deletion polymorphism were carried out. The results of these analyses remained
non-significant (χ2 = 3.442, P = 0.18). However, subjects heterozygous for the insertion/deletion polymorphism showed a slight trend towards lower insulin
values 30 min after an oral glucose load compared to homozygous individuals (P = 0.02). In summary, our results do not support a major role of the human OBR gene in the development of morbid obesity in
our population.
Received: 4 December 1996 / Accepted: 25 June 1997 相似文献