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排序方式: 共有294条查询结果,搜索用时 216 毫秒
1.
Fiona Da Riz Paul Higgs Guillaume Ruiz 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(6):611
Cobalamin concentration is often assessed in clinical practice but little is known about the significance of hypercobalaminemia. The objective of this retrospective study was to identify the conditions associated with hypercobalaminemia in dogs and to investigate association with clinicopathological variables. Medical records of dogs having serum cobalamin measured between 2016 and 2018 were reviewed. One hundred sixty dogs were included and 47 (29%) showed hypercobalaminemia. Dogs with hypercobalaminemia had gastrointestinal (57%), hepatic (11%), neurological (11%), endocrine (9%), renal (4%), pancreatic (2%), and miscellaneous (6%) diseases. Overall, 11% had neoplasia. This distribution was not significantly different from that for hypocobalaminemic and normocobalaminemic dogs. There were significantly more dogs with hyperfolatemia in the hypercobalaminemia group. These results suggest that in clinical practice hypercobalaminemia is commonly identified in gastrointestinal and hepatic disease in dogs, but can also be seen with endocrine and neurological conditions. The frequency of hyperfolatemia alongside hypercobalaminemia may reflect common metabolic pathways. 相似文献
2.
Papantoniou E Hammond EW Tsiami AA Scriven F Gordon MH Schofield JD 《Journal of agricultural and food chemistry》2003,51(4):1057-1063
Fractionation and reconstitution techniques were used to study the contribution of endogenous flour lipids to the quality of semisweet (Rich Tea-type) biscuits. Biscuit flour was defatted with chloroform and baked with bakery fat but without endogenous lipid addition. Semisweet biscuits baked from defatted flour were flatter, denser, and harder and showed collapse of gas cells during baking when compared with control biscuits. Defatted flour semisweet doughs exhibited a different rheological behavior from the control samples showing higher storage and loss moduli (G' and G' ' values), that is, high viscoelasticity. Functionality was restored when total nonstarch flour lipids were added back to defatted flour. Both the polar and nonpolar lipid fractions had positive effects in restoring flour quality, but the polar lipid fraction was of greatest benefit. Both fractions were needed for complete restoration of both biscuit quality and dough rheological characteristics. 相似文献
3.
A recent survey of insecticide resistance in two of the most problematic pests in UK glasshouses revealed some new developments. At least some individuals in all UK samples of Trialeurodes vaporariorum that were tested resisted the insect growth regulator (IGR) buprofezin. The most strongly resistant strains were unaffected by the field application rate of this compound, and even samples from populations that had never been exposed to buprofezin contained individuals that survived the highest concentration applied (10,000 mg litre-1). The field rate of buprofezin was shown to select for resistance through vapour action alone. The benzophenylurea teflubenzuron, an unrelated IGR, was cross-resisted by buprofezin-resistant individuals. There was no evidence of resistance to imidacloprid, but all T vaporariorum strains tested, regardless of origin, exhibited a high innate tolerance to nicotine, when compared with another whitefly species, Bemisia tabaci. Marked resistance to fenbutatin oxide and tebufenpyrad was found in single glasshouse populations of Tetranychus urticae, but these compounds and abamectin appeared to remain highly effective against all other strains collected. 相似文献
4.
John Gordon Bell Fiona Strachan Joanne E Good & Douglas R Tocher 《Aquaculture Research》2006,37(6):606-617
Echium oil (EO) is a vegetable oil in which percentages of stearidonic acid (STA, 18:4n‐3) often exceed those of its n‐6 series equivalent γ‐linolenic acid (GLA, 18:3n‐6). Stearidonic acid is elongated to 20:4n‐3 in fish cell cultures, suggesting that EO could be included in diets for marine fish to increase tissue 20:4n‐3 and 20:3n‐6 and, thereby, modulate eicosanoid metabolism. Thus, the present study aimed to test the hypotheses that dietary EO would increase tissue 20:4n‐3 and 20:3n‐6 and modulate immune function and eicosanoid production in juvenile Atlantic cod (Gadus morhua L.) fed a diet where fish oil (FO) was replaced by EO. Duplicate groups of juvenile cod (initial weight ca. 4 g) were fed for 18 weeks on fish meal‐based diets (55% protein and 16% lipid) that differed in oil source (FO or EO). There were no significant differences in growth and feed efficiency, hepato‐somatic index, percentages of liver and flesh lipids and lipid class compositions for cod fed FO and EO. Percentages of 18:4n‐3, 18:3n‐6 and 20:3n‐6 in the total lipids of flesh and liver were higher, and percentages of 20:5n‐3 and 20:4n‐6 were both lower in fish fed EO than in those given FO. In flesh, the increased 18:3n‐6 and 18:4n‐3 were primarily located in phosphatidylcholine and, to a lesser extent, phosphatidylethanolamine, whereas 20:3n‐6 concentration was highest in phosphatidylinositol. Desaturation of 18:3n‐3 (to tetraene products) and 20:5n‐3 to 22:6n‐3 in hepatocytes was very low but was increased by dietary EO. Echium oil significantly decreased the production of prostaglandin F from gill cells stimulated with calcium ionophore A23187, and reduced head kidney macrophage activity, but had no effect on serum lysozyme activity or basic haematology. In conclusion, dietary EO may have beneficial effects on some immune parameters including eicosanoid metabolism in marine fish although this may be primarily because of decreased 20:4n‐6 rather than increasing tissue levels of 20:3n‐6 or 20:4n‐3. 相似文献
5.
J. Gordon Bell Douglas R. Tocher Fiona M. MacDonald John R. Sargent 《Fish physiology and biochemistry》1994,13(2):105-118
Three practical-type diets utilizing fishmeal and casein as the protein sources and containing fish oil (FO), safflower oil
(SO) or linseed oil (LO) were fed to duplicate groups of juvenile turbot (Scophthalmus maximus) of initial weight 1.2 g for a period of 12 weeks. No differences in final weight, mortality or development of pathological
lesions were evident either between duplicate tanks or between dietary treatments over this period. Fish fed diets containing
SO and LO contained significantly greater amounts of liver triacylglycerol compared to fish fed FO. The major C18 polyunsaturated fatty acids (PUFA) in SO and LO diets, 18:2(n-6) and 18:3(n-3) respectively, were readily incorporated into
both total lipid and individual phospholipids of turbot tissues. There was no accumulation of the Δ6-desaturation products
of these fatty acids, namely 18:3(n-6) and 18:4(n-3), in any of the tissues examined. The products of elongation of 18:2(n-6)
and and 18:3(n-3), 20:2(n-6) and 20:3(n-3) respectively, accumulated in both total lipid and phospholipids with the highest
levels of 20:2(n-6) in liver PC and 20:3(n-3) in liver PE. Eicosapentaenoic acid [EPA, 20:5(n-3)] levels exceeded those of
arachidonic acid [AA, 20:4(n-6)] in phosphatidylinositol (PI) from liver and gill of fish fed LO. EPA levels in liver PI from
fish fed LO were 3-fold and 2-fold greater than SO-fed and FO-fed fish, respectively. Fish fed diets containing SO and LO
had significantly reduced levels of AA in liver and muscle total lipid and lower AA in individual phospholipid classes of
liver and gill compared to FO-fed fish. The concentration of thromboxane B2 was significantly reduced in plasma and isolated gill cells stimulated with calcium ionophore A23187 of fish fed SO and LO
compared to those fed FO. Prostaglandin E produced by isolated gill cells stimulated with A23187 was significantly reduced
in fish fed both SO and LO compared to fish fed FO. 相似文献
6.
Thomas P. Howard Brendan Fahy Fiona Leigh Phil Howell Wayne Powell Andy Greenland Kay Trafford Alison M. Smith 《Journal of Cereal Science》2014
The effects on barley starch and grain properties of four starch synthesis mutations were studied during the introgression of the mutations from diverse backgrounds into an elite variety. The lys5f (ADPglucose transporter), wax (granule-bound starch synthase), isa1 (debranching enzyme isoamylase 1) and sex6 (starch synthase IIa) mutations were introgressed into NFC Tipple to give mutant and wild-type BC2F4 families with different genomic contributions of the donor parent. Comparison of starch and grain properties between the donor parents, the BC2F4 families and NFC Tipple allowed the effects of the mutations to be distinguished from genetic background effects. The wax and sex6 mutations had marked effects on starch properties regardless of genetic background. The sex6 mutation conditioned low grain weight and starch content, but the wax mutation did not. The lys5 mutation conditioned low grain weight and starch content, but exceptionally high β-glucan contents. The isa1 mutation promotes synthesis of soluble α-glucan (phytoglycogen). Its introgression into NFC Tipple increased grain weight and total α-glucan content relative to the donor parent, but reduced the ratio of phytoglycogen to starch. This study shows that introgression of mutations into a common, commercial background provides new insights that could not be gained from the donor parent. 相似文献
7.
Steve Peigneur Ale? ?ula Nace Zidar Fiona Chan-Porter Robert Kirby David Madge Janez Ila? Danijel Kikelj Jan Tytgat 《Marine drugs》2014,12(4):2132-2143
Clathrodin is a marine alkaloid and believed to be a modulator of voltage-gated sodium (NaV ) channels. Since there is an urgent need for small molecule NaV channel ligands as novel therapeutics, clathrodin could represent an interesting lead compound. Therefore, clathrodin was reinvestigated for its potency and NaV channel subtype selectivity. Clathrodin and its synthetic analogues were subjected to screening on a broad range of NaV channel isoforms, both in voltage clamp and patch clamp conditions. Even though clathrodin was not found to exert any activity, some analogues were capable of modulating the NaV channels, hereby validating the pyrrole-2-aminoimidazole alkaloid structure as a core structure for future small molecule-based NaV channel modulators. 相似文献
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10.
Assessment of EST- and genomic microsatellite markers for variety discrimination and genetic diversity studies in wheat 总被引:22,自引:0,他引:22
Fiona Leigh Vince Lea John Law Petra Wolters Wayne Powell Paolo Donini 《Euphytica》2003,133(3):359-366
It is likely that in the near future sequence information from sequencing programmes and EST libraries will generate an abundance
of genic microsatellite markers. This study is focused on the assessment of their likely impact and performance vis-à-vis
their genomic counterparts. Microsatellites from two sources were used to assess the genetic diversity in 56 old and new varieties
of bread wheat on the UK Recommended List. A set of 12 microsatellite markers generated from genomic libraries and 20 expressed
sequence tag (EST)-derived microsatellites were used in the study, and the performance of both marker sets assessed. The EST-derived
or genic microsatellites delivered fingerprints of superior quality, amplifying clear products with few stutter bands. Diversity
levels as revealed bygenic microsatellites are similar to the few published results. The PIC values for the genic markers
were generally lower than those calculated for the genomic microsatellites, though advantages of both marker classes for variety
identification applications are discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献