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191.
Venograms provide information about areas of vascular compression or damage within the hoof. Key areas of the venogram to evaluate include the circumflex vessels, papillae and lamellar circumflex junction. This article describes and illustrates the appearance of the circumflex vessels, papillae and lamellar circumflex junction in sound and laminitic horses. 相似文献
192.
Lattier Jason D. Ballard Harvey E. Kramer Matthew Pooler Margaret R. 《Genetic Resources and Crop Evolution》2022,69(6):2203-2216
Genetic Resources and Crop Evolution - Corylopsis Seibold & Zucc. is a genus of flowering shrubs with few cultivars and little information on genome size, ploidy levels, and genetic... 相似文献
193.
Cats are considered a susceptible host for Dirofilaria immitis; however, increased host resistance is reflected by relatively low adult worm burdens in natural and experimental infections; the prolonged prepatent period (8 months); the low level and short duration of microfilaremia; and the short life span of adult worms (2-3 years). From April to September 2006, 212 cats and 608 dogs, all exposed for at least one transmission season, were screened for D. immitis infection in a multi-center study in the Po River Valley in northern Italy. Cats were initially evaluated by antibody testing; positive subjects were followed up by antigen testing and echocardiography (and necropsy if death occurred). The prevalence in dogs was 29% by a modified Knott test and antigen testing compared with a prevalence of 4.7% in cats by an antibody test; six of these infections (2.8%) were confirmed by the follow-up evaluations. This field study demonstrated that the prevalence of heartworm infection in cats in this area is within the expected limits of 9-18% of the prevalence in dogs. Antibody testing likely underestimates the real prevalence of D. immitis infection in cats. These results also emphasize the importance of preventive treatment in cats. 相似文献
194.
Gyimesi ZS Burns RB Campbell M Knightly F Kramer LW Wack RF Zuba JR Rings DM 《Journal of zoo and wildlife medicine》2011,42(2):281-290
Fatal abomasal impaction, often combined with omasal impaction, was diagnosed in 11 bongo (Tragelaphus eurycerus) from five different zoologic collections in the United States between 1981 and 2009. Nine of 11 cases occurred in young females (10 mo-7 yr old) and typical clinical signs prior to diagnosis or death included partial or complete anorexia, dehydration, and scant fecal production. Although the clinical histories in several of the earlier cases are incomplete, clinical signs were known to begin shortly after an anesthetic event in five of 11 bongo (45%). Pedigree analysis indicates that affected bongo were descendants of multiple founders and not from a single family line, suggesting that the development of abomasal impaction is not a strictly inheritable trait. Treatment, when attempted, was variable and included abomasotomy and removal of impacted ingesta, drug therapy (prokinetic drugs, nonsteroidal anti-inflammatories, antimicrobials), fluid therapy, and administration of oral lubricants or intralesional stool softeners. Based on the outcomes in the cases presented here, the prognosis for bongo with abomasal impaction is considered poor to grave. 相似文献
195.
BACKGROUND: Phytophagous mites such as the European red mite, Panonychus ulmi (Koch), are serious pests in European fruit tree orchards, and a number of acaricides are frequently used to control them. Spirodiclofen (Envidor®) has been a commonly used acaricide for several years. In the present study, European field populations collected in 2009 and 2010 were checked for their susceptibility to spirodiclofen by using discriminating dose and full dose response bioassays. RESULTS: In 2009 and 2010, a total of 63 field populations (including winter eggs) of European red mites were collected in different European countries, and in several populations from south‐western Germany a shifting in susceptibility against spirodiclofen was observed. Full dose response bioassays on different developmental stages of field‐collected strains suggested an age‐dependent expression of resistance because eggs remain fully susceptible to spirodiclofen. Artificial selection with spirodiclofen of one of the field strains resulted in resistance ratios of > 7000. Synergism studies suggest a possible role of cytochrome‐P450‐dependent monooxygenases in spirodiclofen detoxification. Most of the other acaricides from different chemical classes displayed no or low cross‐resistance in a spirodiclofen‐selected strain. CONCLUSION: In order to preserve spirodiclofen as an important tool in spider mite resistance management, the efficacy situation should be continuously monitored, and it is suggested that spirodiclofen be alternated with acaricides coming from different mode‐of‐action classes. An observed age‐specific expression of resistance revealed full susceptibility of eggs, so targeting spirodiclofen particularly against eggs is likely to reduce the selection pressures imposed on other life stages. Copyright © 2011 Society of Chemical Industry 相似文献
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Kramer S 《Science (New York, N.Y.)》1948,108(2797):141-142