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91.
Karine Portier DMV MSc CertVA PhD David Crouzier† PhD Michel Guichardant‡ PhD Michel Prost§ PhD Jean-Claude Debouzy† MD PhD Nathalie Kirschvink¶ DMV PhD Nicole Fellmann MD PhD Pierre Lekeux†† DMV PhD Diplomate ECVPT & Jean Coudert MD PhD 《Veterinary anaesthesia and analgesia》2009,36(4):287-298
ObjectivesTo evaluate whether a period of hyperoxia or after a period of hypoxia produced changes attributable to reactive oxygen species in anaesthetized horses.Study designProspective randomized experimental study.AnimalsSix healthy (ASA I) geldings, aged 4.5–9.5 years and weighing 510–640 kg?1.MethodsAfter 30 minutes breathing air as carrier gas for isoflurane, horses were assigned randomly to breathe air as carrier gas (CG0.21) or oxygen as carrier gas (CG1.00) for a further 90 minutes. After an interval of 1 month each horse was re-anaesthetized with the other carrier gas for the 90 minute test period. Ventilation was controlled throughout anaesthesia. Arterial blood was sampled to measure gas tensions, lactate, cholesterol, vitamin E, 4-hydroxy-alkenals, 8-epi-PGF2α, half haemolysis time, half erythrolysis time, and erythrocyte membrane fluidity. Muscle blood flow and oxygenation were evaluated by near infrared spectroscopy and coloured Doppler.ResultsAfter the first 30 minutes horses were hypoxemic. Subsequently the CG1.00 group became hyperoxaemic (PaO2~240 mmHg) whereas the CG0.21 group remained hypoxaemic (PaO2~60 mmHg) and had increased lactate concentration. No significant changes in vitamin E, 4-hydroxy-alkenals, or 8-epi-PGF2α concentrations were detected. During the 90 minute test period the CG0.21 group had increased resistance to free-radical-mediated lysis in erythrocytes, whereas the CG1.00 group had slightly decreased resistance of whole blood to haemolysis. CG0.21 induced a progressive muscle deoxygenation whereas CG1.00 induced an increase in muscle oxygen saturation followed by progressive deoxygenation towards baseline.Conclusions and clinical relevanceDuring isoflurane anaesthesia in horses, the hyperoxia induced by changing from air to oxygen induced minimal damage from reactive oxygen species. Using air as the carrier gas decreased skeletal muscle oxygenation compared with using oxygen. 相似文献
92.
Diversity of water use efficiency among Quercus robur genotypes: contribution of related leaf traits
Magali Roussel Didier Le Thiec Pierre Montpied Nathalie Ningre Jean-Marc Guehl Oliver Brendel 《Annals of Forest Science》2009,66(4):408-408
93.
Fathia Aouidi Nathalie DupuyJacques Artaud Sevastianos RoussosMonji Msallem Isabelle Perraud GaimeMoktar Hamdi 《Industrial Crops and Products》2012,37(1):292-297
Oleuropein, the major active compound in olive leaf, is well known for its benefits for human health. Oleuropein is classically quantified by HPLC, which is time and chemical consuming, laborious and expensive. The aim of this work was to examine the potential of mid-infrared spectroscopy, as a rapid tool, to predict oleuropein content in olive leaf from five Tunisian cultivars (Chemlali, Chetoui, Meski, Sayali and Zarrazi) and one French cultivar (Bouteillan). The reference data of oleuropein content were obtained by the HPLC method. Hundred five samples were analyzed by HPLC and mid-infrared spectroscopy. Samples were randomly divided in a calibration set (73 samples) and in a validation set (32 samples). The spectral data sets were correlated with reference data of oleuropein content by using partial least squares (PLS) regression algorithm. The results showed that the PLS model gave satisfactory model for quantitative prediction of oleuropein content in olive leaf (relative error of prediction = 8.5%). The correlation coefficient was 0.91 and 0.74 for calibration set and validation set, respectively. It can be concluded that mid-infrared spectroscopy constitutes a promising technique for rapid quantification of oleuropein in olive leaf. 相似文献
94.
Hélène Angellier-Coussy Emmanuelle Gastaldi Nathalie Gontard Valérie Guillard 《Industrial Crops and Products》2011,33(2):457-461
The influence of processing conditions (thermoforming temperature) on water vapour transport properties (permeability, sorption and diffusion) of wheat gluten-based films was studied in relation to structural properties (cross-linking degree of the wheat gluten matrix). Increasing temperature from 80 °C to 120 °C led to a significant decrease in material swelling in high moisture environment and a WVP reduction mainly due to a decrease in diffusivity but without important effect on the moisture sorption isotherms. This was attributed to a higher cross-linking degree of protein network for film thermoformed at 120 °C, with a limited mobility and less possibilities of rearrangement in high moisture conditions. 相似文献
95.
Relationships involving several types of extractives of five native argentine wood species of genera Prosopis and Acacia 总被引:1,自引:0,他引:1
Benedetto Pizzo Carolina L. PomettiJean-Paul Charpentier Nathalie BoizotBeatriz O. Saidman 《Industrial Crops and Products》2011,34(1):851-859
The relationships existing among the values obtained when extracting the wood of four Argentinean species of Prosopis (P. alba, P. kuntzei, P. nigra, and P. ruscifolia) and one of the Acacia (A. aroma) by several procedures were evaluated and discussed. The used methods were: extraction in toluene/ethanol and hot water; determination of tannic and non-tannic content; measurement of phenolic compounds. Additionally, liquid chromatography (HPLC) was also used in order to quantitatively evaluate the content of (−)-mesquitol, a relatively unusual flavonoid (flavanol type). The total amount of Oxidation Products was also measured. They result from oxidation and polymerization processes of phenolic compounds occurring during heartwood formation, and were not separated during chromatographic analysis. Data evidenced a linear trend (R2 = 0.970) between organic and tannic extractives of all species, and a similar one (R2 = 0.927) between total phenols and tannic (or organic) extractives in the case of heartwood of Prosopis species. Interestingly, for sapwood very different values of organic extracts, tannic content or Oxidation Products type compounds were measured in spite of a similar amount of phenolic substances. Moreover, the various species presented the same peaks in chromatograms, thus evidencing the chemical similarity of compounds but a different quantity between heartwood and sapwood and also among the various species. The observed similarity implied that the various methods of extraction did not really extract only a single class of substances, and that great care must be adopted when using some specific procedures for extractions.Furthermore, the existing relationships between extractives and selected technological properties, namely specific volumetric shrinkage coefficient (BSvol) and natural durability (evaluated in terms of mass loss after fungal attacks in laboratory conditions), were given. It appeared that in heartwood BSvol was well correlated to organic extractives (R2 = 0.984), thus evidencing the microimpregnation of cell walls by extractives, but the fitting quality of the correlation was dependent on the type of extractives used. Analogously, a good relationship between mass loss and phenolic compounds existed (R2 = 0.764), and in this case the value of R2 was even more dependent on the considered extracts. Moreover, the availability of quantitative data on several Prosopis species allowed to consistently evaluate the bioactivity of (−)-mesquitol on the resistance against fungal attack, and the logarithmic form of the relationship between mass loss and (−)-mesquitol content suggested a direct fungicidal activity of this compound. On the other hand, data also evidenced that neither phenolic compounds nor (−)-mesquitol can be considered as the unique and definite factor able to determine the durability of the considered species. 相似文献
96.
Leland C. Dickey David B. JohnstonMichael J. Kurantz Andrew McAloonRobert A. Moreau 《Industrial Crops and Products》2011,34(1):845-850
In previous aqueous enzymatic oil extraction (AEOE) experiments we reported a best free oil yield of 49% of the hexane extracted yield of dry fractionated corn germ. In the current experiments, a dispersion of 10% cooked, dry-fractionated germ in water was treated with α-amylase, glucoamylase and a cellulase complex. Free oil was collected by centrifuging a foam fraction of the dispersion. Several dispersion treatments were tried to evaluate their release of free oil and effect on the production of foam. The foam contained up to 8% free oil (dispersed from germ containing 26% oil) and fines oil (not centrifugally separable), protein and germ particles. Treatment with α-amylase and glucoamylase prior to treatment with the commercial cellulase used in previous AEOE studies increased the free oil yields about 25-61% of the hexane-extractable yield. A preliminary cost analysis indicates that oil separation with the amylase enhanced AEOE appears to be preferable to AEOE alone and profitable if crude corn oil cost exceeds $1.1/kg ($0.50/lb). 相似文献
97.
Nathalie Chenais Alexandra Depince Pierre-Yves Le Bail Catherine Labbe 《Aquaculture International》2014,22(1):63-76
Domestication is a long-term process during which wild fish are acclimated to farming conditions and hopefully are reproduced over several generations, possibly using selective breeding. Preservation of the genetic diversity of the original population, together with that of the ongoing selection steps, is important for ecological and economical purposes. Cryobanking of reproductive cells is one answer to meet this need. In fish, however, only sperm can be cryopreserved as neither oocytes nor embryos are capable of handling the freeze-thawing stress. In this review, we explore to what extent diploid cells obtained from fin pieces can be used for the preservation of both parental genomes. The main parameters, which should be under control to ensure proper production of fin cells in culture and to enable cryopreservation of the material are described. After cryobanking of such non-reproductive cells, fish can be reconstructed using the nuclear transfer technology whose potentials and difficulties are discussed. The gametes produced by the fish reconstructed after somatic cells nuclear transfer are different to some extent from the gametes obtained after the direct transplantation of primordial germ cell or spermatogonial germ cells into host embryos or larvae. However, in some cases, only somatic cells can be obtained in quantities which would be compatible with strain restoration purposes. From the knowledge available today, it is reasonable to expect that nuclear transfer becomes available for fish reconstruction, even if restricted to high-tech biotechnology facilities. Therefore, cryobanking of fin somatic cells can be farsightedly considered for high-throughput diploid genome conservation. 相似文献
98.
Response and effect traits of arable weeds in agro‐ecosystems: a review of current knowledge
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S Gaba R Perronne G Fried A Gardarin F Bretagnolle L Biju‐Duval N Colbach S Cordeau M Fernández‐Aparicio C Gauvrit S Gibot‐Leclerc J‐P Guillemin D Moreau N Munier‐Jolain F Strbik X Reboud 《Weed Research》2017,57(3):123-147
Integrating principles of ecological intensification into weed management strategies requires an understanding of the many relationships among weeds, crops and other organisms of agro‐ecosystems in a changing context. Extensively used during the last two decades in weed science, trait‐based approaches have provided general insights into weed community response to agricultural practices, and recently to understanding the effect of weeds on agro‐ecosystem functioning. In this review, we provide a holistic synthesis of the current knowledge on weed response and effect functional traits. Based on the literature and recent advances in weed science, we review current knowledge on (i) weed functional groups and ecological strategies, (ii) weed functional response traits to cropping systems and (iii) weed functional effect traits affecting agro‐ecosystem functioning. For each functional trait, we explicitly present the assumptions and evidence on the linkage between trait values and ecological functions, in response to either management practices, for example tillage, sowing and herbicides, or biotic interactions, for example crop–weed competition and pollination. Finally, we address and discuss major research avenues that may significantly improve the use of traits and the knowledge of functional diversity in weed science for the future, especially to design and implement more environmentally sustainable weed management strategies. 相似文献
99.
Retrospective evaluation of 155 adult equids and 21 foals with tetanus in Western,Northern, and Central Europe (2000–2014). Part 1: Description of history and clinical evolution
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Gaby van Galen DVM PhD DECEIM DECVECC Claude Saegerman DVM PhD DECVPH Joke Rijckaert DVM Helene Amory DVM PhD DECEIM Lara Armengou DVM PhD DECEIM Barbora Bezdekova DVM PhD DECEIM Inge Durie DVM DECEIM Rikke Findshøj Delany DVM Nathalie Fouché DVM DVM Laura Haley MVB Michael Hewetson BVSc DECEIM Rene van den Hoven DVM PhD DECEIM Anna Kendall DVM DECEIM Fernando Malalana DVM DECEIM MRCVS Jessika Muller Cavalleri DVM DECEIM PhD Tresemiek Picavet DVM DECEIM PhD Katja Roscher DVM DECEIM Denis Verwilghen DVM PhD DECVS Meret Wehrli Eser DVM DECEIM Cornélie Westermann DVM PhD DECEIM Tim Mair BVSc PhD DECEIM 《Journal of Veterinary Emergency and Critical Care》2017,27(6):684-696
100.
Anne-Noëlle Petit Nathalie Vaillant-Gaveau Anne-Sophie Walker Pierre Leroux Fabienne Baillieul Marie-Laure Panon Christophe Clément Florence Fontaine 《Crop Protection》2010
Botrytis bunch rot of grapes is mainly controlled by applying fungicides at three crop growth stages: the end of flowering (BBCH 68), bunch closure (BBCH 77) and the beginning of veraison (BBCH 81). The hydroxyanilide derivative fenhexamid is among the most effective fungicides registered to control Botrytis cinerea. Its effectiveness was examined in relation to spray timing, fungicide resistance and defense responses of grapevine. Overall, the earlier fenhexamid was applied, the more effective it was at controlling B. cinerea. Frequencies of B. cinerea strains which were resistant to fungicides were evaluated at harvest. The frequencies of resistant phenotypes were similar among treatments and years with the exception of a class of multidrug resistant strain (MDR 2) whose frequency appeared to increase after fenhexamid applications. If current spray programs including fenhexamid appear to control bunch rot at the current MDR frequency, a propagation of MDR 2 strains might lead to a decline in disease control. Finally, defense responses were studied in grapevine flowers/berries following fenhexamid application. None of the defense processes tested was induced in flowers/berries at stages 68 and 77. Only an increase in chitinase activity was observed in treated-berries at stage 81, suggesting that fenhexamid effectiveness was not related to a stimulation of defense responses. 相似文献