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141.
142.
It is of nutritional significance to fortify processed dairy products (e.g., cheese, yogurt, and ice cream) with vitamin D3; however, the inherent complexity of these foods may influence the stability and bioavailability of this nutrient. In the present study, the interactions of vitamin D3 with beta-lactoglobulin A and beta-casein were investigated under various environmental conditions (i.e., pH and ionic strength) using fluorescence and circular dichroism spectroscopic techniques. The results indicated that vitamin D3 was bound to both beta-lactoglobulin A and beta-casein depending on the solution conditions. The apparent dissociation constants ranged from 0.02 to 0.29 microM for beta-lactoglobulin A, whereas the beta-casein apparent dissociation constants ranged from 0.06 to 0.26 microM. The apparent mole ratios were also comparable, i.e., 0.51-2.04 and 1.16-2.05 mol of vitamin D3 were bound per mole of beta-lactoglobulin A and beta-casein, respectively. It was concluded that these interactions may strongly influence vitamin D3 stability and, hence, bioavailability in processed dairy products. 相似文献
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144.
TH Morris SW Paine PW Zahra EC Li SA Colgan SL Karamatic 《Australian veterinary journal》2020,98(12):578-585
Animals used in sport should be treated as required to ensure animal welfare but any such use of medication should also be controlled to ensure integrity. Pharmacokinetic studies on groups of six greyhounds were performed to measure plasma and urine levels of carprofen and firocoxib to inform medication control advice. Using the standard methodology for medication control the Irrelevant Plasma Concentration was determined as 20 and 2 ng/mL for carprofen and firocoxib, respectively. The Irrelevant Urine Concentration was also determined as 0.3 and 2 ng/mL for carprofen and firocoxib, respectively. These Irrelevant Plasma and Urine Concentrations will allow laboratory Screening Limits, Detection Times and Withdrawal Time advice to be determined and publicised by regulators of greyhound racing. The Screening Limits will also inform Recommended Limits of Detection if meat-containing residues of these medications are fed to greyhounds. 相似文献
145.
目的 探究广州动物园一例死亡白狐Alopex lagopus肾脏中鉴定出的星状病毒的遗传变异情况。方法 对死亡白狐进行剖检,利用半巢式RT-PCR对内脏器官进行病原学检测,对扩增出的病毒株的RdRp基因序列进行相似性分析。结果 死亡白狐的肾脏苍白肿大,被膜难以剥离,肾脏中检测出的星状病毒RdRp基因呈阳性。RdRp基因与9株参考毒株的核苷酸相似性为67.5%~96.2%,其中与香港猫源星状病毒1637F的核苷酸相似性(96.2%)最高。结论 本研究为星状病毒在野生哺乳动物间的跨种传播及肠外器官中的感染提供了依据。 相似文献
146.
【目的】研究蓝刺头花絮水提物的降血糖作用。【方法】采用煎煮法制备蓝刺头花絮水提物。使用四氧嘧啶诱导糖尿病小鼠模型,并随机分为4组,每组10只,蓝刺头高、中、低剂量组小鼠每天分别灌胃1.00,0.50和0.25g/mL的蓝刺头花絮水提物,对照组灌等量蒸馏水,于试验0,7,14和21d测定糖尿病小鼠空腹血糖、体质量;21d测定小鼠口服糖耐量、肝糖原、血清胰岛素、胰高血糖素及肾上腺素的含量。【结果】蓝刺头花絮水提物能够显著降低糖尿病小鼠的空腹血糖,改善糖尿病小鼠的口服糖耐量,升高肝糖原及血清胰岛素水平,极显著降低血清肾上腺素含量,对体质量和血清胰高血糖素含量无显著影响。【结论】蓝刺头花絮水提物能够降低糖尿病小鼠的血糖水平,且呈剂量依赖关系。 相似文献
147.
Estimating illegal and unreported catches from marine ecosystems: a basis for change 总被引:4,自引:0,他引:4
Tony J Pitcher Reg Watson Robyn Forrest Hreiðar Þór Valtýsson & Sylvie Guénette 《Fish and Fisheries》2002,3(4):317-339
To evaluate the impacts of fishing on marine ecosystems, the total extraction of fish must be known. Putting a figure on total extraction entails the difficult task of estimating, in addition to reported landings, discards, illegal and unmandated catches. Unreported catches cast various types of shadow, which may be tracked and estimated quantitatively. Some shadows of unreported catches are reviewed, for example, an innovative, well‐funded NGO publicizes illegal catch in the Southern Ocean. For various reasons, official figures often have the implicit but unacceptable assumption that such categories are null. We present an estimation procedure based on adjustment factors taken from observer reports, correspondents and published information that track changes in a regulatory regime, and hence reflect incentives and disincentives to misreport. Monte Carlo simulations address uncertainty using multiple sources of information to provide upper and lower estimates. Once in place, this method provides preliminary estimates that may be refined without disruption. The method is demonstrated for fisheries in Iceland and Morocco. We use a ‘by‐species’ approach for Icelandic cod and haddock, while the Moroccan catch is divided into demersal and pelagic categories. Results suggest that Icelandic cod catches may have been underestimated by between 1 and 14% at different times, and haddock by between 1 and 28%. Underestimation of Moroccan catches appears to have been as much as by 50%. These case studies show that it is possible to obtain estimates of misreporting, even when direct data are lacking. Our method encourages transparency because sources of information are presented so that uncertain values are easily identified, offering a basis for comment, collaboration and refinement in estimating illegal and unreported fishing. 相似文献
148.
Philina A. English Eric J. Ward Christopher N. Rooper Robyn E. Forrest Luke A. Rogers Karen L. Hunter Andrew M. Edwards Brendan M. Connors Sean C. Anderson 《Fish and Fisheries》2022,23(1):239-255
Species responses to climate change are often measured at broad spatiotemporal scales, which can miss the fine-scale changes that are most relevant to conservation and fisheries management. We develop a scaleable geostatistical approach to assess how juvenile and adult fish distributions have been shaped by changes in bottom temperature and dissolved oxygen over a recent decade of warming in the northeast Pacific. Across 38 demersal fishes, biomass trends were associated negatively with warming and positively with dissolved oxygen, but when trends in both biomass and climate were converted to velocities—the speed and direction a population would have to move to maintain consistent conditions—the effect of temperature change differed depending on local conditions. In the warmest locations, warming velocities were associated with negative biotic velocities for 19 of 69 species-maturity combinations, and yet were almost always associated with stable or positive biotic velocities in the coolest locations (64 of 69). These spatially consistent biomass declines (negative biotic velocities) in the warmest locations and increases in cooler locations suggest a redistribution of species with the potential for new ecological and fisheries interactions. After controlling for temperature, the more spatially consistent effects of dissolved oxygen were often negative, suggesting a mechanism other than hypoxia avoidance—potentially changes in primary production. Our approach identifies the species and locations that are most sensitive to observed changes in the environment at any scale, thus facilitating future vulnerability assessments. 相似文献
149.
Murphy SM Lawrence JA Schmiedt CW Davis KW Lee FT Forrest LJ Bjorling DE 《The Journal of small animal practice》2011,52(6):329-333
An eight-year-old female spayed Airedale terrier with rapid recurrence of a nasal adenocarcinoma following image-guided intensity-modulated radiation therapy was treated with transnasal, image-guided cryotherapy. Ice ball size and location were monitored real-time with computed tomography-fluoroscopy to verify that the entire tumour was enveloped in ice. Serial computed tomography scans demonstrated reduction in and subsequent resolution of the primary tumour volume corresponding visually with the ice ball imaged during the ablation procedure. Re-imaging demonstrated focallysis of the cribriform plate following ablation that spontaneously resolved by 13 months. While mild chronic nasal discharge developed following cryoablation, no other clinical signs of local nasal neoplasia were present. Twenty-one months after nasal tumour cryoablation the dog was euthanased as a result of acute haemoabdomen. Image-guided cryotherapy may warrant further investigation for the management of focal residual or recurrent tumours in dogs, especially in regions where critical structures preclude surgical intervention. 相似文献
150.