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71.
Kim N. Hamilton Sarah E. Ashmore Rod A. Drew 《Genetic Resources and Crop Evolution》2008,55(5):683-693
The comparative morphology of the seeds of three Australian Citrus species, C. australasica C. inodora and C. garrawayi, was studied. Their seed characteristics were broadly similar to those of the cultivated species of the genus, when observed
under light and scanning electron microscopy. Citrus garrawayi differed in seed shape (rounded to triangular) and seed coat morphology (i.e., thicker with longer epidermal protrusions)
from C. australasica and C. inodora (rounded surface with flat underside in shape). The well-developed minute epidermal protrusions on the seed coat of C. garrawayi were more similar to those in the cultivated species, C. × sinensis and C. × aurantium. In contrast, the surface topography of C. australasica and C. inodora seeds was more like that of the cultivated species, C. × aurantifolia and C. × limon. Seed morphology, especially surface topography, was found to be a useful tool for taxonomic identification in Australian
wild citrus. 相似文献
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73.
Edwards DS Coyne K Dawson S Gaskell RM Henley WE Rogers K Wood JL 《Preventive veterinary medicine》2008,87(3-4):327-339
Feline upper respiratory tract disease (URTD), mainly caused by feline calicivirus (FCV) and feline herpesvirus, is a major cause of disease outbreaks in feline accommodation such as animal shelters, catteries and multi-cat households. We conducted a longitudinal, yearlong study in five UK feline animal shelters to identify risk factors for the time to diagnosis of URTD. We were especially interested in risk factors that could be identified at the time the cat entered the shelter. Shelter staff recorded data for 1434 cats during 2002–2003. Most of the cats were domestic shorthair cats and were from private households, or were stray or abandoned. Sixty cats without clinical signs of URTD at entry had URTD diagnosed (typically within the first month at the centre). We used two multivariable models: one was a Cox proportional-hazards model, and the other a regression analyses with complementary log–log model.The hazard varied substantially between shelters and was considerably lower for the shelter that had a purpose-built admissions unit with its own isolation facilities. The hazard was greater for purebred cats (HR 4.3–5.0) and for neutered cats (HR 2.0). The hazard was also typically greater if the centre had a greater proportion of cats present with URTD. The analyses suggested that the centre-level risk factors were more important in determining hazard than cat-level risk factors. 相似文献
74.
Susan Dawson 《The Journal of small animal practice》2008,49(12):607-607
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Jaime Viscasillas Richard Everson Emma Kate Mapletoft Charlotte Dawson 《Veterinary anaesthesia and analgesia》2019,46(2):246-250
Objective
To describe a novel ultrasound-guided posterior extraconal block in the dog.Study design
Prospective experimental cadaveric study.Animals
A total of 13 Beagle Cross cadaver heads.Methods
After describing the ultrasound bony landmarks and posterior extraconal local regional technique in one head, 12 heads were used to evaluate the spreading of contrast and evaluate potential complications. A 5–8 MHz microconvex ultrasound probe was positioned caudal to the orbital ligament, with the beam orientated transversely, and then tilted caudally until the orbital fissure was visualized. After identifying the bony structures consistent with the orbital fissure, a needle was advanced using an in-plane technique and 0.5 mL of a 50:50 mixture of iohexol and methylene blue was injected. Computed tomography (CT) and dissection were used to evaluate successful injections and potential complications. The injection was considered successful if radiopaque contrast medium was 5 mm from the orbital fissure. Potential complications were defined as the presence of radiopaque contrast within the globe or the intracalvarial tissues.Results
The CT images confirmed contrast at the target site in 15/24 (63%) of the injections. Only two injections were found in the temporalis muscle; the rest of the injections were located in the extraconal space. No potential complications such as intracranial spreading of contrast, intravascular or intraocular injection were found.Conclusions and clinical relevance
The technique can deliver contrast close to the main nerves which provide sensory and motor innervation to the eye. Further studies are needed to evaluate this technique in clinical cases. 相似文献78.
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CASE HISTORY: A 400-cow dairy unit in the Waikato suffered a severe outbreak of facial eczema (FE) despite consistent zinc supplementation and significantly elevated serum zinc concentrations. CLINICAL FINDINGS: FE prevention had begun in mid-January 2006, via zinc sulphate supplementation in the water. Photosensitisation was reported on 06 April, contemporaneous with a marked increase in the number of Pithomyces chartarum spores in pasture samples. Within 10 days of this first clinical case, 100 affected cows had been dried off, eight of which subsequently died or were culled. Blood samples were collected from ten affected cows; all had serum zinc concentrations >17 micromol/L, and eight had gamma-glutamyl transferase (GGT) activities >200 U/ml, indicating that the photosensitisation was secondary to liver damage, i.e. probably FE. Further investigation identified that this herd had been receiving excess copper supplementation; 4/6 culled cows had liver copper concentrations within or above the marginal range for copper toxicity. DIAGNOSIS: Severe FE despite zinc supplementation that increased serum zinc concentrations above recommended levels. CLINICAL RELEVANCE: As zinc supplementation significantly reduces apparent copper status, copper supplementation is often used to counteract this. Previous excess copper intake may reduce the efficacy of zinc in preventing FE, thus copper intake should be assessed prior to the start of zinc supplementation. 相似文献