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531.
Webb CB 《Clinical Techniques in Small Animal Practice》2002,17(2):79-85
Effective troubleshooting for a diabetic small animal patient starts with the initial diagnosis of diabetes. Preempting trouble with a thorough and complete history, physical examination, laboratory assessment, and extensive and thoughtful client education before discharge, are crucial first steps toward avoiding trouble altogether. As problems arise, careful consideration of the many variables that contribute to effective diabetic control is necessary. As monitoring strategies evolve and treatment options expand, the clinician's ability to accurately assess and adjust the glycemic control in his or her troubled diabetic patient improves. Common causes of trouble in diabetic patients are reviewed and various strategies for the diagnosis and management of these disorders are discussed in this article. Every effort was made to draw from recently published reports of clinical cases. Few diseases will tie together owner, patient, and therapy as intimately as diabetes mellitus, and few problems will be solved without fully considering all potential factors. 相似文献
532.
Steven A. Barben Bryan G. Hopkins Von D. Jolley Bruce L. Webb Brandt A. Nichols Emily A. Buxton 《Journal of plant nutrition》2013,36(8):1144-1163
Three hydroponic experiments were conducted with Russet Burbank potato to elucidate zinc (Zn) and manganese (Mn) relationships and associated interactions with other nutrients at different levels of phosphorus (P). Except when P was optimal, root Mn concentration was reduced at optimal solution Zn relative to deficient or excessive Zn levels. Shoot Mn generally increased with augmented solution Zn. As solution Zn increased, root P declined while shoot P and copper (Cu) and root iron (Fe) and Cu increased. Increasing solution Mn generally decreased Zn in all plant tissues—especially in roots. The Mn influence on plant P, Cu, and Fe concentrations was nearly opposite the Zn impact, indicating that Zn and Mn have counter effects. Partitioning between root and shoot micronutrient concentrations occurred when available P was either deficient or excessive, which may also help explain poor plant health and adverse micronutrient relationships in potato when available P is not optimally maintained. 相似文献
533.
R. S. Pitcher P. C. R. Webb 《The Journal of Horticultural Science and Biotechnology》2013,88(2):95-100
Seed of the Potentate variety of tomato was sown at weekly intervals for 56 weeks and weekly measurements of the diameters of every fruit were made to provide estimates of fruit volume production. Development of the plants could suitably be divided into the following periods : (a) from germination to the start of fruiting, (b) an initial lag in fruit volume production, (c) rapidly increasing production, (d) declining production and (e) arrested development, when fruit swelling virtually ceased.The duration of the period from germination to the start of fruiting was related to day-length.The condition of arrested fruit development occurred from approximately the shortest day to the vernal equinox in mature plants that had already attained a maximal rate of fruit volume production ; in juvenile plants it occurred, and was maintained, from approximately the autumnal equinox to the vernal equinox, i.e. when the duration of darkness exceeded that of the light. In both juvenile and mature plants the condition of arrested fruit development ceased when the duration of the light exceeded that of darkness, and a period of increasing fruit volume production ensued.The rate of fruit volume production during this period of rapid increase was related to day-length and the relation was curvilinear. It continued to increase as long as the days continued to lengthen. When the day-length began to decline so also did the rate of production and the relation with day- length was linear. 相似文献
534.
535.
Campbell AJ Croser EL Milne ME Hodge PJ Webb Ware JK 《Australian veterinary journal》2012,90(6):235-239
Background Several outbreaks of goitre, considered to be related to iodine deficiency, occurred in sheep flocks throughout Victoria in 2010. Objective We describe one outbreak in Merino–Border Leicester‐cross ewes and their lambs in north‐east Victoria that appeared to be associated with increased rainfall and pasture growth, particularly during the preceding summer and autumn. Results The outbreak was characterised by a four‐fold increase in neonatal lamb deaths and goitre, alopecia and poor skeletal development in the lambs. Most cases occurred in lambs born to 2‐year‐old crossbred ewes that had grazed long, lush perennial pastures throughout their entire pregnancy, whereas few cases occurred in mature crossbred or Merino ewes that had grazed shorter, annual pastures on hill country for 3 weeks in late pregnancy but were otherwise managed similarly. Conclusion Existing recommendations for south‐eastern Australia are that only spring‐lambing ewes in iodine‐deficient areas require iodine supplementation to prevent goitre in years with high autumn–winter rainfall. Aspects of this outbreak suggest that ewes lambing at other times of the year and grazing abundant pasture for prolonged periods may also require supplementation to prevent goitre, even if autumn–winter rainfall does not exceed previously established thresholds. 相似文献
536.
Weiner CM Smirnova NP Webb BT Van Campen H Hansen TR 《Research in veterinary science》2012,93(2):1081-1088
Non-cytopathic bovine viral diarrhea virus (ncpBVDV) induces immune responses mediated by chemokines and interferon (IFN) stimulated genes (ISGs). Cultured bovine peripheral blood mononuclear cells (PBMC) from ncpBVDV-naïve cattle were used herein to demonstrate that BVDV infection modulates chemokine receptor 4 (CXCR4), CXCL12, IFN-I, ISGs and selected immune cell marker (CD4, CD8, CD14) mRNAs, and that these acute responses to viral infection are reflected in PBMC cultured with serum from heifers carrying fetuses persistently infected (PI) with ncpBVDV. Infection of PBMC with ncpBVDV increased IFN-β, ISG15, RIG-I, CXCR4, CXCL12, and CD8 mRNA concentrations after 32 h. Culture of PBMC with uterine vein serum from acutely infected heifers, inoculated with ncpBVDV during early gestation to generate PI fetuses, also increased the concentration of CXCR4, RIG-I and ISG15 mRNAs. In vitro PBMC treatment with ncpBVDV or uterine vein serum from acutely infected pregnant heifers activates chemokine, ISG and immune cell responses. 相似文献
537.
Escrivão RJ Webb EC Garcês AP Grimbeek RJ 《Tropical animal health and production》2012,44(7):1779-1782
Sixty multiparous Brahman-type cows were randomly selected in the early postpartum period and equally allocated into a calf removal group (RG) and a non-removal group (NRG). Calves from cows in the RG were removed for 48 h prior to the breeding season and returned afterwards, whereas in the NRG, calves remained with their dams until weaning. Weaning weights were corrected to 205?days. Conception rates (CRs) were 76?% for RG and 55?% for NRG but did not differ (p?>?0.05). CR was correlated with calving to breeding interval and body condition score at the onset of the breeding season. Product-limit survival curves vs breeding to conception interval differed significantly (p?0.05) between treatment groups. It was estimated with 95?% certainty that 50?% of the cows in the RG will conceive within the first 12?days of the breeding season, while 39?days were required for cows in the NRG. Weaning weights were 135.2?±?22?kg for RG and 135.5?±?19?kg for NRG. It was concluded that 48-hour calf removal prior to breeding season increased the number of cows that conceive early in the breeding season and enhanced conception rates but did not affect calf weaning weights of Bos indicus cattle in extensive production systems. 相似文献
538.
Plasmopara halstedii, the causal agent of downy mildew of sunflower, is an oomycete listed as a quarantine pathogen. This obligate parasite resides in a quiescent state in seeds of sunflower and can be spread from seed production areas to areas of crop production by international seed trade. To prevent the spread or the introduction of potentially new genotypes or fungicide-tolerant strains, an efficient method to detect P. halstedii in sunflower seed is required. This work reports the optimization of a real-time detection tool that targets the pathogen within sunflower seeds, and provides statistically validated data for that tool. The tool proved to be specific and inclusive, based on computer simulation and in vitro assessments, and could detect as few as 45 copies of target DNA. A fully optimized DNA extraction protocol was also developed starting from a sample of 1,000 sunflower seeds, and enabled the detection of <1 infected seed/1,000 seeds. To ensure reliability of the results, a set of controls was used systematically during the assays, including a plant-specific probe used in a duplex quantitative polymerase chain reaction that enabled the assessment of the quality of each DNA extract. 相似文献
539.
B6.Cg-Tg(Thy1-YFP)16Jrs/J transgenic mice were created to express the yellow fluorescent protein gene driven by a mouse Thy1 promoter that labeled motor and sensory neurons such that individual nerves could be followed. These mice were used to identify nerves in the skin that innervate the erector pili and panniculus carnosus muscle. Whole mounts demonstrated yellow fluorescent protein expression in nerves of the skin, which was confirmed by labeling the neuromuscular junction with fluorescinated α-bungarotoxin. Frozen and paraffin-embedded skin sections revealed innervation of the panniculus carnosus muscle. Paraffin sections labeled with an anti-green fluorescent protein antibody revealed innervation of the panniculus carnosus as well as the erector pili muscle and around the hair follicle bulge. 相似文献
540.
W.M Allen K.S Cheah P Imlah D Lister D.E Steane A.J Webb 《Livestock Production Science》1980,7(4):305-315
Pale, soft, exudative (PSE) pigmeat is not common in the U.K. There is, therefore, no great pressure for the introduction of tests to identify potentially affected animals. Commercial and research organisations are, however, anxious to keep a watching brief and to evaluate the established and novel tests for predicting and monitoring porcine stress syndrome (PSS) and PSE in pig populations. Of these, serum enzyme measurements, halothane sensitivity, blood grouping and mitochondrial calcium efflux have received the greatest attention. Most of the tests examined readily predict the worst examples of the syndrome, but are not sufficiently precise to be able to identify tendencies towards it, which restricts their value in breeding programmes. There are no plans to incorporate any of the tests in the national (MLC) testing programme. 相似文献