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排序方式: 共有676条查询结果,搜索用时 437 毫秒
261.
262.
Stephen T. Sinatra Raj K. Chopra Stanley Jankowitz David W. Horohov Hemmi N. Bhagavan 《Journal of Equine Veterinary Science》2013
Although the importance of coenzyme Q10 (CoQ10) in health and disease and its critical role in cellular bioenergetics have been well established in various species, there is a total lack of information on the role of CoQ10 in horses. Therefore, the present study was undertaken first to ascertain the occurrence of CoQ10 and/or possibly other homologs of coenzyme Q (CoQ) in horse serum, and then to examine the response to CoQ10 supplementation on serum CoQ10 concentration. The study was carried out with 2-year-old Thoroughbred horses. Total CoQ (reduced and oxidized forms) in serum was assayed by high-performance liquid chromatography. The data show that horse serum contains CoQ as CoQ10, at a much lower concentration as compared with that of humans and several other species. There is no evidence for the presence of coenzyme Q9 or other homologs of CoQ. On supplementation with CoQ10 at 800 mg a day (1.47 mg/kg body weight), there was a significant increase in serum CoQ10 concentration, approximately 2.7-fold at 60 days. CoQ10 supplementation at this dosage was found to be safe and well tolerated. Additional studies are needed to examine whether maintaining higher serum CoQ10 concentrations is of potential health benefit to the horses, as assessed by selected biochemical markers and also in terms of performance. 相似文献
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In humans with atopic dermatitis (AD), the epicutaneous application of allergens (atopy patch tests or APT) to which the patients are sensitized often results in the development of inflammation resembling that of spontaneous skin lesions. Dogs are affected with a natural homologue of human AD, but information on the induction of positive patch testing reactions is limited. The objectives of this pilot study were to determine the nature and cellular dynamics of inflammation occurring after APT in dogs hypersensitive to house dust mite and flea allergens. Laboratory Beagles were sensitized experimentally to Dermatophagoides farinae house dust mites (two dogs), Ctenocephalides felis flea saliva (one dog) or both (two dogs). Two other dogs served as nonsensitized controls. Both allergens and saline were applied epicutaneously. Macroscopic evaluations and skin biopsies were performed at 4, 24, 48 and 96 h after starting allergenic challenge. Biopsies were evaluated histologically and immunohistochemically with a panel of monoclonal antibodies specific for canine leucocyte antigens. Positive macroscopic reactions consisted of erythema, oedema and induration, and they occurred between 24 and 96 h after allergen application. Macroscopic and microscopic APT reactions developed only whenever serum IgE was present against tested allergens. Microscopically, positive APT was associated with epidermal hyperplasia, Langerhans' cell hyperplasia, and eosinophil and lymphocyte epidermotropism. Dermal inflammation was mixed and arranged in a superficial perivascular to interstitial pattern. Numerous IgE+-CD1+ dendritic cells and gamma-delta T-lymphocytes were observed. Macroscopically and microscopically, APT reactions in these experimentally sensitized animals resembled those seen in lesional biopsy specimens of dogs and humans with spontaneous AD. Therefore, APT in hypersensitive dogs provides a relevant experimental model to investigate the pathogenesis and treatment of both canine and human AD skin lesions. 相似文献
266.
Kangethe Erastus K. Mulinge Erastus K. Skilton Robert A. Njahira Moses Monda Joseph G. Nyongesa Concepta Mbae Cecilia K. Kamwati Stanley K. 《Tropical animal health and production》2012,44(1):25-31
A total of 1,734 cattle faecal samples from 296 dairy-keeping households were collected from urban settings in Nairobi, Kenya. Modified Ziehl–Neelsen staining method and an immunofluorescence assay were used to identify those samples with Cryptosporidium oocyst infection. Oocysts from positive faecal samples were isolated by Sheather's sucrose flotation method and picked from the concentrate using cover slips. Genomic DNA was extracted from 124 of the faecal samples that were positive for Cryptosporidium and was used as template for nested PCR of the 18S rRNA gene. Twenty-five samples (20 %) were PCR-positive for Cryptosporidium, and 24 of the PCR products were successfully cloned and sequenced. Sequence and phylogenetic analysis identified 17 samples (68 %) as Cryptosporidium parvum-like, four samples (16 %) as Cryptosporidium ryanae, three samples (12 %) as Cryptosporidium andersoni and one sample (4 %) as Cryptosporidium hominis. To the best of our knowledge, this is the first genotyping study to report C. parvum-like, C. andersoni and C. hominis in cattle from Kenya. The results of this study show Cryptosporidium infections in calves and cattle may be potential zoonotic reservoirs of the parasite that infects humans. 相似文献
267.
Inès Dufey Patrice Hakizimana Xavier Draye Stanley Lutts Pierre Bertin 《Euphytica》2009,167(2):143-160
Lowland rice is often subject to iron toxicity which may lead to yield reduction. In order to cope with this nutrient disorder,
plants have developed resistance strategies. The aim of this research was to assess morphological and physiological parameters
linked to iron toxicity resistance mechanisms and to identify quantitative trait loci (QTLs) involved in their genetic determinism.
A segregating population consisting of 164 recombinant inbred lines (RILs) derived from a cross between Azucena and IR64 was
tested twice in hydroponics at the vegetative stage at 0 and 250 mg Fe2+ l−1. Morphological traits were measured on all 164 RILs. Physiological traits, which were too time-consuming to allow their measurement
on all the population, were measured on the two parents and extreme individuals only, selected on the basis of their leaf
bronzing index and shoot dry weight. A total of 24 putative QTLs was identified on chromosomes 1, 2, 3, 4, 7 and 11 for leaf
bronzing index, shoot water content, shoot and root dry weight, relative variation of shoot and root dry weight, shoot iron
concentration, stomatal resistance and chlorophyll content index. Several QTLs were detected in overlapping regions for different
parameters. The pertinence of phenotyping extreme RILs only for a QTL analysis is discussed in this study. The QTL analysis
allowed to better understand the physiological response of rice in the presence of an excess of ferrous iron, inclusive the
relations existing between the stomata closure, the shoot water content reduction and the oxidative stress linked to these
growth conditions. 相似文献
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Economic analysis of revenue losses and control costs associated with the spotted wing drosophila,Drosophila suzukii (Matsumura), in the California raspberry industry
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270.
Rachael K. Lau Anneke Moresco Sarah J. Woods Christopher M. Reilly Michelle G. Hawkins Christopher J. Murphy Steven R. Hollingsworth Dennis Hacker Kate S. Freeman 《Veterinary ophthalmology》2017,20(6):560-567
A juvenile to young adult, male, great horned owl (Bubo virginianus,GHOW) was presented to the wildlife rehabilitation hospital at Lindsay Wildlife Museum (WRHLWM) due to trauma to the right patagium from barbed wire entanglement. On presentation, both corneas were irregular, dry, and no movement of the third eyelid was noted. A severe corneal enlargement/globoid appearance was the predominant ophthalmic feature. The fundus was normal in both eyes (OU). Over the course of several days, both corneas developed edema combined with further dessication at the ocular surface associated with diffuse dorsal fluorescein stain uptake. Repeated ophthalmic examinations found normal intraocular pressures and an inability to move the third eyelid over the enlarged corneas. The bird was deemed nonreleasable due to severe wing damage and poor prognosis associated with eye abnormalities and was humanely euthanized. Postmortem CT, enucleation, and histopathology were performed to evaluate the ocular anatomical abnormality and confirm the suspected diagnosis of keratoglobus. This GHOW represents the first reported case of presumptive keratoglobus in a raptor. 相似文献