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951.
952.
OBJECTIVE: To assess microorganisms isolated from blood specimens obtained from critically ill neonatal foals and to evaluate their antimicrobial susceptibility patterns. DESIGN: Retrospective study. ANIMALS: 543 neonatal foals. PROCEDURE: Medical records of foals that were < 1 month old and were admitted to a referral neonatal intensive care unit were reviewed for results of bacteriologic culture of blood and antimicrobial susceptibility patterns. RESULTS: At least 1 microorganism was isolated from 155 of 543 (28.5%) foals. Escherichia coli was the most commonly isolated bacterium. A single gram-positive organism was detected in 49 foals. Although 90% of the E coli isolates were susceptible to amikacin, some gram-negative and gram-positive organisms had resistance against multiple antimicrobials. CONCLUSIONS AND CLINICAL RELEVANCE: Gram-negative bacteria remain the most common isolates from blood of neonatal foals; however, gram-positive organisms were also found, and with greater prevalence than reported elsewhere. Susceptibility patterns may vary, and resistance to multiple antimicrobials may develop. This is especially true for organisms such as Enterobacter spp and Enterococcus spp. Prudent empirical treatment for neonatal sepsis should include broad-spectrum antimicrobials.  相似文献   
953.
OBJECTIVE: To investigate the effect on ovine footrot of repeated daily footbathing in a solution of zinc sulphate with surfactant. DESIGN: Merino sheep were allocated to control and treatment groups of 119 sheep each at week 0. The sheep had a history of S1, U1, T and/or U6 types of Dichelobacter nodosus in interdigital and underrunning footrot lesions. Feet were not pared prior to treatment. PROCEDURE: Treatment sheep were footbathed in a 15 to 18% (w/v) solution of zinc sulphate with surfactant for 10 min on five consecutive days during week 1. At week 2, and fortnightly to week 52, all feet were inspected, lesion scores were recorded and samples were taken for laboratory tests. At week 53, all feet with no lesions at week 52, but with underrunning lesions prior to week 1, were pared and samples were taken. RESULTS: After footbathing, there were no lesions in any treatment sheep at any inspection to week 52. The percentage of feet of control sheep with lesions increased from 9% (391 of 4,284) between weeks 20 and 36, to 14% (593 of 4,284) between weeks 36 and 52. Ninety-five of 96 control sheep with no lesions at week 20 were still asymptomatic at week 52. D nodosus was not isolated from samples taken from 99 and 87 pared feet of treatment and control sheep, respectively. CONCLUSION: Repeated daily footbathing combined with prolonged exposure to a dry environment eradicated footrot in sheep with both interdigital and underrunning lesions in feet that were not pared prior to treatment.  相似文献   
954.
Several pathovars of Pseudomonas syringae produce the phytotoxin coronatine (COR)in vitro, and the availability of purified toxin has facilitated development of immunological detection methods. A modified, indirect competitive ELISA using the COR-specific monoclonal antibody 11B8 was developed to detect COR in various host plants infected by P. syringae. The estimated detection limit for COR was 50 pg per well, and COR could be reliably quantified from 5 to 40 ng ml−1. The subcellular localization of COR within infected tomato tissue was investigated using the COR-specific antibody MAb 8H3G2. Immunofluorescence microscopy and immunogold labelling showed that COR was present inside tomato cells and was associated with chloroplasts and particles of proteinase inhibitor I. Localization studies indicated that COR is mobile in infected plant tissue and can be detected in healthy tissue adjacent to the bacterial lesions.  相似文献   
955.
Retinopathy in sheep affected with natural scrapie   总被引:2,自引:0,他引:2  
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956.
957.
Use of a neodymium:yttrium-aluminum-garnet laser to remove exuberant granulation tissue from the esophagus of a horse A 4-year-old Quarter Horse mare was evaluated because of recurrent esophageal obstruction. Endoscopic examination revealed a proliferative mass in the esophagus approximately 55 cm aborad to the nares. Histologic examination of biopsy specimens revealed diffuse suppurative esophagitis and granulation tissue with no evidence of neoplasia. The mass was excisedand ablated transendoscopically with a neodymium:yttrium-aluminum-garnet laser. During a follow-up examination 2 weeks after the final laser procedure, the mass was no longer apparent, and the esophagus appeared healed. Six months after the final examination, there had been no recurrence of the mass. In this horse, transendoscopic laser excision was efficacious and avoided problems associated with an esophagotomy.  相似文献   
958.
Fifteen mated bitches were given prostaglandin F2 alpha (PGF2 alpha) [250 micrograms/kg body weight] and bromocriptine (10 micrograms/kg BW) twice daily from days 6 to 10 of diestrus. Progesterone concentrations declined during treatment. None of the bitches whelped. Daily treatment with PGF2 alpha and bromocriptine for 5 d appears to induce luteolysis and prevent early pregnancy.  相似文献   
959.
960.
A heterogeneous patchwork mosaic of soil, vegetation, and built surfaces that result from a variety of urban land uses cause urban microclimates within cities. We studied the seasonal relationships of land use, urban plant cover and microclimate in Phoenix, Arizona, USA, metropolitan. Early morning (0500 HR) and afternoon (1500 HR) near-surface temperatures and humidities were measured along multiple transects in this desert city and outlying areas during June and December 1999. A Landsat thematic mapper normalized differential vegetation index (NDVI) image was used to quantify spatial patterns of plant density. Land use had the most pronounced effect on microclimate during the early morning hours of summer. Agricultural and residential land uses had the highest relative humidities, dew point temperatures, and NDVI, and the lowest air temperatures. Commercial and industrial land uses had highest temperatures and lowest NDVI. Temperatures were generally negatively correlated to NDVI, while humidity and dew point temperatures were generally positively correlated to NDVI. Distance from the urban core did not affect NDVI but had a significant negative effect on adjusted air temperature. In addition, a historical comparison of land use, NDVI and microclimate data collected during 1976 and again during 1999 along two transects revealed overall decreases in NDVI and relative increases in air temperature indicative of urban expansion. These findings show that microclimates in this desert city are caused by more than just variations in plant cover, and are likely an interactive effect of vegetation density and other non-vegetative urban surfaces.  相似文献   
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