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101.
Raphaël Jumeau Phuc Félix Nguyen-Tan Houda Bahig Xavier Liem Louise Lambert Matthieu Schmittbuhl Dany Simard Edith Filion 《Reports of Practical Oncology and Radiotherapy》2018,23(4):270-275
Aim
To develop a tool in order to guide pre-irradiation dental care (PIDC) for patients with oropharyngeal cancers.Background
Osteoradionecrosis of the jaws is a potential complication of radiotherapy (RT) for head and neck cancers. To prevent this complication, PIDC can involve multiple dental extractions as a preventative measure to avoid post-RT complications. However, there is no standardized tool to guide PIDC.Materials and methods
From January 2005 to October 2015, 120 head and neck cancer patients were prospectively included in a study investigating dysgeusia after RT. From this cohort, patients were enrolled according to the following inclusion criteria: histopathological confirmation of oropharyngeal squamous cell carcinoma; stage T1-4 N1-3 M0; ≤10 missing teeth. Individual teeth were retrospectively delineated on planning computed tomography and doses to dentition were assessed to generate templates.Results
Thirty-three patients were included. Molars received highest doses with a mean dose of 50?Gy (range; 19–75?Gy). Ipsi-lateral and contralateral wisdom teeth received RT dose superior to 50?Gy in 92% and 56% of cases, respectively. Patients with advanced disease (T4 or N2c-3) received higher mean doses on inferior and ipsi-lateral dental arches compared to other patients (T1-3 N0-2b): 42?Gy vs. 39?Gy and 44?Gy vs. 39?Gy (p?<?0.05), respectively.Conclusion
Pre-RT dose distribution templates are an objective way to prepare PIDC. Further studies with a larger cohort are needed to validate these templates. 相似文献102.
A reliable technique to quantify the individual variability of iridescent coloration in birds 下载免费PDF全文
Sonia Van Wijk Marc Bélisle Dany Garant Fanie Pelletier 《Journal of avian biology》2016,47(2):227-234
The study of iridescent coloration in birds emerged only recently, mainly due to the difficulty inherent in quantifying its directionality. Directionality restrains color perception to a limited angle and thereby causes drastic changes in brightness when an animal is in motion. Although a versatile goniometer for quantifying iridescent coloration has been developed recently, so far, it has only been applied to measuring the highly directional iridescent coloration in a hummingbird species. Thus, the reliability of the goniometer for species displaying more common and less directional iridescent coloration has yet to be evaluated. Additionally, two important methodological aspects remain to be assessed before this apparatus can be used confidently: 1) whether directionality, which could be subject to sexual selection, can be quantified in a repeatable way; and 2) whether the apparatus gives more precise and accurate measurements than a less complex traditional method. Using feathers collected from 271 male tree swallows Tachycineta bicolor over two years, we found that the goniometer provided repeatable measurements of directionality across individuals and across three body regions, namely the crown, mantle and rump. The apparatus was also more repeatable than a traditional method involving a bifurcated probe and reduced a brightness bias associated with individual differences in barbule tilt. We strongly encourage researchers to invest in this methodological change considering the multiple advantages demonstrated and to quantify the directionality of iridescent coloration as to unveil its role in signaling and sexual selection. 相似文献
103.
Michel Poulain Anne Herm Dany Chambre Gianni Pes 《Biodemography and social biology》2016,62(3):262-274
The question of whether mothers’ fertility history influences their post-reproductive survival has been addressed frequently in the scientific literature. Using data from Villagrande Strisaili, Sardinia, where longevity is higher than anywhere else in Europe, we analyzed the relationship between the fertility pattern of mothers who survived past age 50 (n = 539) and their post-reproductive lifespan. We find that, after adjustment for potential confounders (mothers’ birth cohort, survival of spouse), the mothers who on average delivered their children later displayed a reduced mortality risk (?2.9 percent for each additional year), supporting previously reported findings. We also find that a male-skewed offspring ratio was associated with decreased mortality risk of mothers, with longer survival of mothers who delivered their sons above age 35 (p = 0.005), a result not found for daughters. So far, no biological explanation has been suggested for the positive effect of delivering sons later in life. We conjecture that in our dataset stronger nonbiological factors such as gender-specific sociocultural and economic factors may have masked the negative effect reported in other populations, for which a biological explanation was proposed. 相似文献
104.
Guillaume Desroches Dany Gagnon Sylvie Nadeau Milos Popovic 《Journal of electromyography and kinesiology》2013,23(6):1325-1333
The purpose of this study was to investigate the effects of imposing different degrees of forward trunk flexion during sitting pivot transfers on electromyographic activity at the leading and trailing upper limb muscles and on dynamic stability requirements. Thirty-two individuals with a spinal cord injury performed three types of sitting pivot transfers: natural technique, exaggerated forward trunk flexion and upright trunk position. Ground reaction forces, trunk kinematics, and bilateral electromyographic activity of eight upper limb muscles were recorded. Electromyographic data were analyzed using the area under the curve of the muscular utilization ratio. Dynamic stability requirements of sitting pivot transfers were assess using a dynamic equilibrium model. Compared to the natural strategy, significantly greater muscle activities were found for the forward trunk flexion condition at the anterior deltoid and both heads of the pectorialis major, whereas the upright trunk strategy yielded greater muscle activity at the latissimus dorsii and the triceps. The forward flexed condition was found to be more dynamically stable, with a lower stabilizing force, increased area of base of support and greater distance traveled. Thus, transferring with a more forward trunk inclination, even though it increases work of few muscles, may be a beneficial trade-off because increased dynamic stability of this technique and versatility in terms of potential distance of the transfer. 相似文献
105.
The aim of this study is to determine the affinity of six active compounds of Aegle Marmelos Correa, they are (E, R)-Marmin,
skimmianine, (S)-aegeline, aurapten, zeorin, and dustanin as antihistamines in histamine H1 receptor in comparison to cetirizin,
diphenhydramine and chlorpheniramine as ligands comparison. Previously, in the in vitro study marmin obviously antagonized
the histamine H1 receptor in a competitive manner. Methods: molecular docking to determine the interaction of ligand binding to its
receptor. Lower docking score indicates more stable binding to that protein. Results: Marmin, skimmianine, aegeline, aurapten,
zeorin, and dustanin were potential to develop as antihistamine agents, especially as histamine H1 receptor antagonists by
interacting with amino acid residues, Asp107, Lys179, Lys191, Asn198, and Trp428 of histamine H1 receptor. Conclusions: Based on
molecular docking, Amino acid residues involved in ligand protein interactions were Asp107, Lys179, Lys191, Asn198, and Trp428. 相似文献
106.
Susanne Denzau Dany Kuriakose Rafael Freire Ursula Munro Wolfgang Wiltschko 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2011,197(12):1137-1141
Young domestic chicks of two strains, ISA brown layers and White Leghorn X Australorps, were trained to associate a magnetic
anomaly with food. This was done by feeding them in their housing boxes from a dish placed above a small coil that produced
a magnetic anomaly roughly six times as strong as the local geomagnetic field. Unrewarded tests began on day 9 after hatching.
In a square arena, two corresponding coils were placed underneath two opposite corners. One coil, the control coil, was double-wrapped
producing no net magnetic field, while the other in the opposite corner produced a local magnetic anomaly similar to that
experienced during feeding. The chicks favoured the corner with the anomaly from day 10 after hatching onward. Both strains
of chickens showed this preference, indicating that they could sense the local changes in the magnetic field. 相似文献
107.
Dany Azar ré Nel Michel Solignac Jean-Claude Paicheler & Françoise Bouchet 《Palaeontology》1999,42(6):1101-1136
Until now, only two Psychodoidea were known from Lebanese amber. We describe two new genera and species of Phlebotomidae ( Mesophlebotomites hennigi gen. et sp. nov., Libanophlebotomus lutfallahi gen. et sp. nov.) and four new genera with six new species of Psychodidae ( Paleopsychoda solignaci gen. et sp. nov., Paleopsychoda jacquelinae sp. nov., Protopsychoda nadiae gen. et sp. nov., Protopsychoda hammanaensis sp. nov., Libanopsychoda abillamai gen. et sp. nov., Cretapsychoda inexpectata gen. et sp. nov.) from the Lower Cretaceous amber of Hammana/Mdeirij, Lebanon. These fossils are included in a phylogenetic analysis of the subfamilies of Psychodoidea. This superfamily was probably as diverse in the Early Cretaceous as now. 相似文献
108.
Gene expression and metabolite profiling of Populus euphratica growing in the Negev desert 总被引:4,自引:0,他引:4 下载免费PDF全文
Brosché M Vinocur B Alatalo ER Lamminmäki A Teichmann T Ottow EA Djilianov D Afif D Bogeat-Triboulot MB Altman A Polle A Dreyer E Rudd S Paulin L Auvinen P Kangasjärvi J 《Genome biology》2005,6(12):R101-17
Background
Plants growing in their natural habitat represent a valuable resource for elucidating mechanisms of acclimation to environmental constraints. Populus euphratica is a salt-tolerant tree species growing in saline semi-arid areas. To identify genes involved in abiotic stress responses under natural conditions we constructed several normalized and subtracted cDNA libraries from control, stress-exposed and desert-grown P. euphratica trees. In addition, we identified several metabolites in desert-grown P. euphratica trees.Results
About 14,000 expressed sequence tag (EST) sequences were obtained with a good representation of genes putatively involved in resistance and tolerance to salt and other abiotic stresses. A P. euphratica DNA microarray with a uni-gene set of ESTs representing approximately 6,340 different genes was constructed. The microarray was used to study gene expression in adult P. euphratica trees growing in the desert canyon of Ein Avdat in Israel. In parallel, 22 selected metabolites were profiled in the same trees.Conclusion
Of the obtained ESTs, 98% were found in the sequenced P. trichocarpa genome and 74% in other Populus EST collections. This implies that the P. euphratica genome does not contain different genes per se, but that regulation of gene expression might be different and that P. euphratica expresses a different set of genes that contribute to adaptation to saline growth conditions. Also, all of the five measured amino acids show increased levels in trees growing in the more saline soil. 相似文献109.
110.
The effects of increasing plant diversity on the population of the coffee leaf-miner Leucoptera coffeella (Guérin-Mèneville) were investigated in two organic coffee production systems. One system consisted of coffee intercropped with banana trees (shaded system) and the other one of coffee intercropped with pigeon pea (unshaded system). The increase in plant diversity on both systems was achieved via introduction of green manures such a perennial pea nut, sunn hemp and Brazilian lucerne. The population of L. coffeella, predation and parasitism of L. coffeella mines were biweekly evaluated during eight months. The increase in plant diversity on both systems did not affect the attack of L. coffeella on coffee leaves and the mine parasitism rate. However, there was a positive and significant relationship between increasing plant diversity and coffee leaf mine predation by wasps on unshaded coffee system and a negative relationship on shaded coffee system. 相似文献