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排序方式: 共有446条查询结果,搜索用时 500 毫秒
141.
Fradette ME Céleste C Richard H Beauchamp G Laverty S 《American journal of veterinary research》2007,68(2):128-133
OBJECTIVE: To evaluate the effects of continuous oral administration of phenylbutazone on serum and synovial fluid biomarkers of skeletal matrix metabolism in horses. ANIMALS: 11 adult female horses without clinical or radiographic evidence of joint disease. PROCEDURES: Horses were randomly assigned to control or treatment groups. Phenylbutazone was administered orally twice daily at a dose of 4.4 mg/kg for 3 days to the treatment group and subsequently at a dose of 2.2 mg/kg for 7 days. Serum and radiocarpal synovial fluid samples were obtained at baseline and thereafter at regular intervals for 4 weeks. Biomarkers of cartilage aggrecan synthesis (chondroitin sulfate 846) and type II collagen synthesis (procollagen type II C-propeptide) and degradation (collagen type II cleavage) were assayed. Biomarkers of bone synthesis (osteocalcin) and resorption (C-terminal telopeptide of type I collagen) were also measured. RESULTS: No significant differences were found between control and treatment groups or temporally for the biomarkers chondroitin sulfate 846, procollagen type II C-propeptide, collagen type II cleavage, and C-terminal telopeptide of type I collagen in serum or synovial fluid. A significant increase in osteocalcin concentration occurred in synovial fluid during treatment in the treated group. No treatment effect was detected for serum osteocalcin concentration. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that continuous phenylbutazone administration at recommended doses altered some biomarkers in healthy equine joints after short periods of administration. Increased osteocalcin concentration may indicate an undetermined anabolic effect of phenylbutazone administration on periarticular bone or transient induction of osteogenesis in articular chondrocytes or a mesenchymal subpopulation of synoviocytes. 相似文献
142.
Marie M Meyerholz Kirsten Mense Michael Lietzau Ana Kassens Matthias Linden Hendrike Knaack Elisa Wirthgen Andreas Hoeflich Mariam Raliou Christophe Richard Olivier Sandra Hans-Joachim Schuberth Martina Hoedemaker Marion Schmicke 《Journal of veterinary science (Suw?n-si, Korea)》2015,16(4):413-421
This study was conducted to determine if the main components of the somatotropic axis change during the early phase of pregnancy in the maternal blood system and whether differences exist on day 18 after pregnancy recognition by the maternal organism. Blood samples of pregnant heifers (Holstein Friesian; n = 10 after embryo transfer) were obtained on the day of ovulation (day 0), as well as on days 7, 14, 16 and 18 and during pregnant, non-pregnant and negative control cycles. The oncentrations of progesterone (P4), oestrogen, growth hormone (GH), insulin-like growth factor-1 and -2 (IGF1, -2) and IGF-binding protein-2, -3 and -4 (IGFBP2, -3, -4) were measured. The mRNA expressions of growth hormone receptor 1A, IGF1, IGF2, IGFBP2, IGFBP3 and IGFBP4 were detected using RT-qPCR in liver biopsy specimens (day 18). In all groups, total serum IGF1 decreased from day 0 to 16. Notably, IGFBP4 maternal blood concentrations were lower during pregnancy than during non-pregnant cycles and synchronized control cycles. It can be speculated that the lower IGFBP4 in maternal blood may result in an increase of free IGF1 for local action. Further studies regarding IGFBP4 concentration and healthy early pregnancy are warranted. 相似文献
143.
Bouzouidja Ryad Béchet Béatrice Hanzlikova Jitka Sněhota Michal Le Guern Cécile Capiaux Hervé Jean-Soro Liliane Claverie Rémy Joimel Sophie Schwartz Christophe Guénon René Szkordilisz Flora Körmöndi Barnabas Musy Marjorie Cannavo Patrice Lebeau Thierry 《Journal of Soils and Sediments》2021,21(5):1909-1927
Journal of Soils and Sediments - In urban areas, soil functions are deeply impacted by all human activities, e.g., water infiltration, carbon storage, and chemical substances degradation potential.... 相似文献
144.
Lucia Barra Raghu Chandrasekaran Federico Corato Christophe Brunet 《Marine drugs》2014,12(3):1641-1675
In this review, we aim to explore the potential of microalgal biodiversity and ecology for biotechnological use. A deeper exploration of the biodiversity richness and ecophysiological properties of microalgae is crucial for enhancing their use for applicative purposes. After describing the actual biotechnological use of microalgae, we consider the multiple faces of taxonomical, morphological, functional and ecophysiological biodiversity of these organisms, and investigate how these properties could better serve the biotechnological field. Lastly, we propose new approaches to enhancing microalgal growth, photosynthesis, and synthesis of valuable products used in biotechnological fields, mainly focusing on culture conditions, especially light manipulations and genetic modifications. 相似文献
145.
146.
Rederstorff E Fatimi A Sinquin C Ratiskol J Merceron C Vinatier C Weiss P Colliec-Jouault S 《Marine drugs》2011,9(2):224-241
Polysaccharides are highly heat-sensitive macromolecules, so high temperature treatments are greatly destructive and cause considerable damage, such as a great decrease in both viscosity and molecular weight of the polymer. The technical feasibility of the production of exopolysaccharides by deep-sea bacteria Vibrio diabolicus and Alteromonas infernus was previously demonstrated using a bioproduct manufacturing process. The objective of this study was to determine which sterilization method, other than heat sterilization, was the most appropriate for these marine exopolysaccharides and was in accordance with bioprocess engineering requirements. Chemical sterilization using low-temperature ethylene oxide and a mixture of ionized gases (plasmas) was compared to the sterilization methods using gamma and beta radiations. The changes to both the physical and chemical properties of the sterilized exopolysaccharides were analyzed. The use of ethylene oxide can be recommended for the sterilization of polysaccharides as a weak effect on both rheological and structural properties was observed. This low-temperature gas sterilizing process is very efficient, giving a good Sterility Assurance Level (SAL), and is also well suited to large-scale compound manufacturing in the pharmaceutical industry. 相似文献
147.
A 3-year-old, female black-tailed prairie dog (Cynomys ludovicianus) was presented for complications related to an earlier rhinostomy procedure and placement of a breathing tube for treatment of a pseudo-odontoma. The complaint by the owner was that the prairie dog would constantly remove the breathing tube. The breathing tube was replaced with a human earlobe retractor positioned (partially) under the nasal bones. The patient tolerated the procedure and location of the human earlobe retractor. This is the first reported case using a human earlobe retractor to function as a permanent rhinostomy device in a prairie dog. 相似文献
148.
Verspreet J Pollet A Cuyvers S Vergauwen R Van den Ende W Delcour JA Courtin CM 《Journal of agricultural and food chemistry》2012,60(9):2102-2107
An improved method for the measurement of fructans in wheat grains is presented. A mild acid treatment is used for fructan hydrolysis, followed by analysis of the released glucose and fructose with high performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD). Not only the amount of fructose set free from fructans but also the released glucose can be quantified accurately, allowing determination of the average degree of polymerization of fructans (DP(av)). Application of the mild acid treatment to different grain samples demonstrated that a correction should be made for the presence of sucrose and raffinose, but not for stachyose or higher raffinose oligosaccharides. The fructan content and DP(av) of spelt flour, wheat flour, and whole wheat flour were 0.6%, 1.2%, and 1.8% of the total weight and 4, 5, and 6, respectively. Validation experiments demonstrate that the proposed quantification method is accurate and repeatable and that also the DP(av) determination is precise. 相似文献
149.
Mélanie Villeret Sabrina Jolly Laure Wiest Emmanuelle Vulliet Anne Bado-Nilles Jean-Marc Porcher Stéphane Betoulle Christophe Minier Wilfried Sanchez 《Fish physiology and biochemistry》2013,39(3):573-580
The aim of this study was to identify a signal that could be used as an androgen exposure indicator in the European bullhead (Cottus sp.). For this purpose, the ultra-structure of the kidney was characterized to identify normal structure of this organ, and histological changes previously described in the kidney of breeding male bullheads were quantified using the kidney epithelium height (KEH) assay previously developed and validated for the stickleback. In the next step, the effect of trenbolone acetate (TbA), a model androgen, was assessed to identify potential androgenic regulation of bullhead kidney hypertrophy. Measurement of KEH performed on adult non-breeding male and female bullheads exposed for 14 and 21 days to 0, 1.26 and 6.50 μg/L showed that kidney hypertrophy is induced in a dose-dependent manner, confirming the hypothesis that the European bullhead possesses a potential biomarker of androgen exposure. Combined with the wide distribution of the European bullhead in European countries and the potential of this fish species for environmental toxicology studies in field and laboratory conditions, the hypothesis of a potential biomarker of androgen exposure offers interesting perspectives for the use of the bullhead as a relevant sentinel fish species in monitoring studies. Inducibility was observed with high exposure concentrations of TbA. Further studies are needed to identify molecular signals that could be more sensitive than KEH. 相似文献
150.
Quantification of Wheat TAXI and XIP Type Xylanase Inhibitors: A Comparison of Analytical Techniques
Kurt Gebruers Johnny Beaugrand Evi Croes Emmie Dornez Christophe M. Courtin Jan A. Delcour 《Cereal Chemistry》2008,85(5):586-590
To date, three different techniques are available for the quantification of TAXI and XIP type proteinaceous xylanase inhibitors in cereals. A first approach is based on the determination of the residual activities of xylanases (also referred to as endo‐1,4‐β‐d ‐xylanases, EC 3.2.1.8), which are specifically inhibited by these inhibitors, after incubation with sample containing the inhibitors. The other two techniques are immunoblotting and ELISA which are based on recognition of TAXI and XIP proteins by specific antibodies. TAXI, as well as XIP, are easily extracted by aqueous buffers. Hence, the large difference in their concentrations (2–10 fold higher for XIP than for TAXI in whole meal) is not caused by differences in extractability. The repeatabilities of the three techniques are comparable. The intra‐assay and inter‐assay coefficients of variation were 6–7 and 10–14%, respectively, which is in the range of values described for methods to quantify other compounds in plant and animal tissues. The three methods give comparable results, suggesting they have similar accuracies. The choice of the technique to be used will depend not only on the sensitivity and dynamic range needed, but also on its technical simplicity and the need for high‐throughput analysis. 相似文献