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991.
Dr. Joachim Kakau Dorothee Abdel-Kader Petra Müller Karl-Heinz Pastrik Luitgardis Seigner 《Gesunde Pflanzen》2004,56(4-5):95-104
Zusammenfassung In den Jahren 1999 bis 2003 wurde in Freiland-, Klimakammer- und Lagerungsversuchen überprüft, ob ein Risiko für die Übertragung des Erregers der Bakteriellen Ringfäule der Kartoffel (Clavibacter michiganensis ssp. sepedonicus) besteht, wenn (a) gesunde Kartoffelknollen in Kontakt mit Maschinen und Geräten kommen, die mit dem Erreger kontaminiert sind (indirekter Kontakt) und (b) gesunde Kartoffelknollen direkt in Kontakt mit infizierten Knollen kommen (direkter Kontakt). Nach indirektem Kontakt konnte nur beim nachfolgenden Anbau der kontaminierten Knollen in der Klimakammer Befall in Kraut und Knollen festgestellt werden. Im Freiland konnte der Erreger, auch bei wiederholtem Nachbau der geernteten Knollen, nicht nachgewiesen werden. Nach direktem Kontakt und nachfolgendem Anbau der kontaminierten Knollen in der Klimakammer und im Freiland, wurde der Erreger in allen Fällen in den geerntete Knollen nachgewiesen. Befall im Kraut wurde nur in dem Klimakammerversuch und in einem Freilandversuch ermittelt. Wurden durch direkten Kontakt kontaminierte Knollen eingelagert, konnte der Erreger in allen untersuchten Knollen festgestellt werden. Insgesamt besteht ein hohes Risiko, dass gesunde Knollen infiziert werden, wenn oberflächliche Kontaminationen mit dem Erreger erfolgen. Die Wahrscheinlichkeit von Infektionen steigt mit zunehmender Kontaminationsstärke. 相似文献
992.
现已证明,在酵母中产生的一种新型的6-植酸酶比其他在市场上供应的植酸酶的效率至少高20%。因为6-植酸酶与其他商品化的植酸酶相比,可进一步减少无机磷源的使用,从而降低生产成本以及磷的污染。 相似文献
993.
S.G. Nykamp DVM P.V. Scrivani DVM A.P. Pease DVM MS 《Veterinary radiology & ultrasound》2004,45(1):23-28
Computed tomography-dacryocystography (CT-DCG) was used to evaluate the nasolacrimal system in four patients (three dogs and one horse) that were admitted for evaluation of chronic epiphora, facial swelling, or facial trauma. The four patients are reviewed and the technique for performing CT-DCG is described. Additionally, the indications for this procedure are discussed. CT-DCG is advantageous because cross-sectional imaging provides superior resolution of the nasolacrimal apparatus and the relatively long, small-diameter, bony nasolacrimal canal in most veterinary patients. 相似文献
994.
M. C. Owen BVSC C. R. Lamb MA VETMB D. Lu BVET. MED. MVM M. P. Targett BA VETMB PHD 《Veterinary radiology & ultrasound》2004,45(2):149-155
The aim of this study was to determine the prevalence and potential significance of finding material in the middle ear of dogs having magnetic resonance (MR) imaging. Of 466 MR studies reviewed, an increased signal was identified in the tympanic bulla in 32 (7%) dogs. Cavalier King Charles spaniels, Cocker spaniels, Bulldogs, and Boxers were over-represented compared to the population of dogs having MR imaging. Five (16%) dogs had definite otitis media and one (3%) had a meningioma invading the middle ear. Of the remaining dogs, 13 (41%) had possible otitis media and 13 (41%) had neurologic conditions apparently unrelated to otitis media. The most common appearance of material in the middle ear was isointense in T1-weighted images and hyperintense in T2-weighted images. There was no apparent correlation between the signal characteristics of the material and the diagnosis. Enhanced signal after gadolinium administration was observed affecting the lining of the bulla in dogs with otitis media and in dogs with unrelated neurologic conditions. In dogs without clinical signs of otitis media, finding an increased signal in the middle ear during MR imaging may reflect subclinical otitis media or fluid accumulation unrelated to inflammation. Brachycephalic dogs may be predisposed to this condition. 相似文献
995.
Marnie M Ford 《Veterinary Clinics of North America: Small Animal Practice》2004,34(3):669-691
Many variables affect the outcome of keratomycosis and systemic fungal infections in animals. These include pathogenicity of the fungal organism(toxins, trophisms, and evasion of host response); previous treatment with topical or systemic corticosteroids, which can have a dramatic negative impact on host defense mechanisms: concurrent systemic illness or immunocompromise: severity/extent of infection; and degree of pain (ie,increased reflex tearing dilutes topical medication) [14]. Experimental work suggests that antibiotics may occasionally exacerbate fungal infections [142],and some researchers advocate that concurrent antibiotic therapy is contraindicated in horses with yeast infections and septate fungal infections unless bacterial infection is also suspected [14]. Nevertheless, given that normal conjunctival flora often include bacteria and fungi and because care of keratomycoses often includes mixed bacterial and fungal infections, the possible dynamics (natural influences and local competition) between ocular surface microorganisms merit further investigation. There are many unanswered questions regarding the accuracy of in vitro susceptibilities and corneal concentration capabilities for antifungal topical medications [14].Inherent host resistance or other immune interactions between the patient and fungus are perhaps the most important determinants of the outcome but are currently difficult to measure or assess except by subjective clinical observation [14]. 相似文献
996.
997.
Susan M Carastro 《Veterinary Clinics of North America: Equine Practice》2004,20(2):285-299
This article is intended to provide the practitioner with a succinct but complete source regarding equine orbital and ocular anatomy,instrumentation available for ophthalmic examination, a methodical examination technique, sedation and regional nerve blocks, and diagnostic procedures involving the eye. Such knowledge of orbital and ocular anatomy is essential to allow recognition of normal,normal variations, or an abnormality of the equine eye and orbit. 相似文献
998.
999.
1000.
Benjamin Brault DVM James Hoskinson DVM Laura Armbrust DVM George Milliken PhD 《Veterinary radiology & ultrasound》2004,45(4):298-304
The purpose of this study was to evaluate seven digital cameras for their ability to adequately capture quality radiographic images and their relative cost effectiveness. Radiographs of line pair (LP) phantoms (ranging from 0.6 to 16.6 LP/mm) and a 20-step contrast phantom were photographed at a near distance of 30.0 cm and a far distance (determined for each camera) at which a full 14 x 17 in film filled the viewfinder. Of the seven cameras tested, the Canon EOS-D30 consistently performed the best in LP/mm resolved (7.7 at close distance, 1.4 at far distance) and in contrast latitude (all 20 steps at both close and far distances). The Canon EOS-D30, determined to be the best camera used in this study for photographing radiographic images, is also the most expensive camera that was used. Two cameras, the Nikon Coolpix 995 and the Sony DSC-F707, were very close to the Canon in performance at considerably less cost. Certain inexpensive cameras may not be acceptable choices for teleradiology. 相似文献