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61.
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ABSTRACT

Field experiments were conducted in North Carolina to determine peach response to herbicides. Mesotrione, rimsulfuron, and sulfentrazone did not injure newly planted peach trees. However, halosulfuron at the higher rate caused injury to peach trees, but did not reduce tree cross-sectional area or winter pruning weight. Another field experiment was conducted to determine the effect of herbicide-based programs on weed control. Sulfentrazone alone controlled common lamb’s-quarters and henbit but provided poor control of large crabgrass and yellow foxtail. However, a tank mix of norflurazon or oryzalin with sulfentrazone improved control of these weeds over sulfentrazone alone. Terbacil alone or in tank mix rimsulfuron, and flumioxazin alone gave excellent control of large crabgrass and yellow foxtail.  相似文献   
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Calves, sensitised by cutaneous application of dinitrochlorobenzene, developed lesions of delayed hypersensitivity at the sites of application nine to 14 days later. Leucocytes from sensitised calves, collected 10 to 16 days after sensitisation, reacted in an in vitro leucocyte adherence inhibition test with the same hapten in water soluble form, dinitrobenzenesulphonate. The leucocyte adherence inhibition microtest which was simple, rapid, reproducible and amenable to rigorous statistical analysis, should find use in many areas of bovine immunology.  相似文献   
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The US Agency for International Development (USAID) works within the overall purpose of US foreign assistance to improve the lives of the citizens of the developing world. Through partnerships with other agencies, organizations, and governments, and using its field offices around the world, USAID strives to develop local capacity and thus build sustainable development. Two specific USAID programs pertinent to veterinary medicine are global health and agriculture. In the area of global health, veterinarians can aid USAID's work to improve the quality, availability, and use of essential health services that specifically target maternal and child health, HIV/AIDS, family planning and reproductive health, infectious diseases, environmental health, nutrition, and other life-saving areas. The challenge of making the agricultural sector in a developing country more productive is a critical one for USAID and a clear area for input from the veterinary profession. Animal agriculture is the largest single sector of agricultural economies in most developing countries, and livestock remains a critical component of poverty alleviation. There are educational requirements that benefit anyone working at USAID and can be met prior to admittance to a DVM program, as part of a DVM curriculum, or in post-graduate training/employment, such as proficiency in a foreign language; environmental sciences background; familiarity with accounting and management techniques; expertise in foreign animal diseases, zoonotic diseases, epidemiology, food safety, and nutrition, as well as the application to human health of those areas; an advanced degree such as an MPH; and management experience. Appropriately trained veterinarians can make enormous contributions to USAID's global efforts to improve the health and agriculture sectors of developing nations.  相似文献   
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Functioning Tri13 and Tri7 genes are required for the production of nivalenol and 4-acetyl nivalenol, respectively, in Fusarium species producing type B trichothecenes. Mutations have been identified in isolates which are able to produce deoxynivalenol (DON) but unable to convert this to nivalenol (NIV). In such isolates of Fusarium culmorum , the Tri7 gene is deleted entirely. PCR assays specific for functional and nonfunctional/deleted versions of Tri7 and Tri13 were used to determine the ability of 153 single spore isolates of F. culmorum to produce the 8-ketotrichothecenes deoxynivalenol and nivalenol. The isolates were collected from 76 different locations across England and Wales between 1994 and 2002. Four isolates were also obtained from one field in Scotland. Both DON and NIV chemotypes of F. culmorum were identified, with DON chemotypes predominating overall. In addition, all DON chemotypes were shown to produce 3-acetyl DON using primer sets developed to Tri3 . From fields where more than one F. culmorum isolate was obtained, isolates were not exclusively of a single chemotype. Differences in the distribution of DON and NIV chemotypes were identified, with a greater proportion of NIV chemotypes present in the south and west of England and Wales, whereas a greater proportion of DON chemotypes were found in the north and east of England. Seasonal differences in the ratio of DON:NIV chemotypes were indicated. However, these were related to seasonal variation in the distribution of F. culmorum .  相似文献   
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A 2.5-year-old dog with congenital pulmonary valve dysplasia was treated by percutaneous balloon dilation of the stenotic orifice. Clinical and hemodynamic improvement was apparent immediately and for 9 months after the valvuloplasty procedure.  相似文献   
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