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971.
972.
R W Young 《Journal of agricultural and food chemistry》1970,18(1):164-167
973.
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975.
Brett M. Havis Kelsey E. Walker Pamela R. F. Adkins Zhenyu Shen John R. Middleton Tamara Gull Dusty Nagy Dae Young Kim 《Journal of veterinary diagnostic investigation》2021,33(3):587
A 3-mo-old male llama was examined because of a 4-wk history of lethargy and ill thrift. Clinical examination revealed subcutaneous masses in the left prescapular and right inguinal regions, mild ataxia, a slight head tilt to the right, and right ear droop. The cria died before clinical workup was complete. At autopsy, there was generalized lymphadenomegaly, a hepatic nodule, a midbrain mass causing rostral compression of the cerebellum, and internal hydrocephalus. Microscopic findings included pyogranulomatous lymphadenitis, meningoencephalitis, hepatitis, and bronchopneumonia. Intralesional fungal spherules, most consistent with Coccidioides spp., were identified in the lymph nodes, lung, and brain. Fungal culture, single-nucleotide variation genotyping real-time PCR, and DNA sequencing confirmed Coccidioides posadasii. The dam of the cria was native to Arizona and had been moved to Missouri ~2.5 y previously. Agar gel immunodiffusion assay of the herd revealed that only the dam was positive for Coccidioides spp.; 6 herdmates were negative. Computed tomography of the dam revealed multiple nodules within the lungs and liver, which were presumed to be an active coccidioidomycosis infection. This case of systemic coccidioidomycosis in a llama native to Missouri was presumably acquired by vertical transmission from the dam. 相似文献
976.
Shaw DR Owen MD Dixon PM Weller SC Young BG Wilson RG Jordan DL 《Pest management science》2011,67(7):741-746
Glyphosate-resistant (GR) crop technology has dramatically impacted agriculture. The adoption of GR systems in canola, maize, cotton, soybean and sugar beets has been widespread in the United States. However, weed scientists are concerned that growers' current herbicide programs and weed management tactics will affect their sustainability and effectiveness. Without proper management, the potential for weed populations to express a high degree of resistance to glyphosate will adversely impact the utility of glyphosate. In 2005, weed scientists from six universities initiated a long-term research study to assess the sustainability of GR technology. This paper introduces five other articles in this series. Over 150 fields of at least 10 ha were selected to participate in a long-term field-scale study, and each field was split in half. On one-half the grower continued using the current weed management program; on the other half the grower used academic-recommended herbicide resistance best management practices. Field data were collected in 2006-2008 to determine the impact of the two weed management programs on weed populations, diversity, seedbank, crop yields and economic returns. This long-term study will provide invaluable data for determining the sustainability and profitability of diversified weed management programs designed to lower the risk of evolving weed resistance to glyphosate. 相似文献
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978.
Shannon T Ferrell Annajane B Marlar Allison C Alberts Lee A Young Kelly Bradley Sandra L Hurlbut Nancy P Lung 《Journal of zoo and wildlife medicine》2005,36(4):712-715
Twenty-four juvenile to subadult Anegada iguanas (Cyclura pinguis), captive-reared in a propagation facility, were designated by a coordinated recovery program for release in the summer of 2003. To facilitate postrelease monitoring, a radiotransmitter device was placed within the coelomic cavity of each animal under general anesthesia before release. The equipment sterilization technique and the method of attachment of the transmitters to the coelomic body wall resulted in functional transmitters and acceptably low rates of mortality associated with the procedure. 相似文献
979.
B. A. Sharp L. G. Young A. A. van Dreumel 《Canadian journal of veterinary research》1972,36(4):398-402
Forty-eight weanling S.P.F. Yorshire pigs were used to study the influence of supplemental vitamin E (25 IU per kg of diet) selenium (0.5 ppm in diet) and methionine (0.1% in diet) on the incidence of hepatosis dietetica and mulberry heart disease when fed a torula yeast-corn diet. Vitamin E and/or selenium increased pig survival. Supplemental selenium resulted in increased liver selenium concentrations. No hepatosis dietetica was observed in any of the pigs. The addition of vitamin E and/or selenium at the levels used did not reduce the frequency of myocardial lesions; however, they prevented skeletal muscular dystrophy and exudative diathesis. The myocardial lesions were less severe in supplemented pigs compared with unsupplemented controls. 相似文献
980.
C. J. Young 《Southern Forests》2013,75(1):86-89
Effective mechanical and chemical control techniques have been developed for almost all the important woody, alien, invasive plants in Natal. Despite this, progress with the actual control of these plants has been disappointing. Possible reasons for this include poor control practices, a lack of extension work, wrong attitudes and too much reliance on biological control. An approach is proposed which will address these and other problems. Research is to concentrate on the implementation of available control techniques to determine their cost-effectiveness when applied on a large scale and also over the long term, e.g. aspects such as post control management of the vegetation. This is to be done with the so-called “land-unit based” approach which will also serve to transfer the most suitable technology to the end-user. 相似文献