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981.
The objective of this study was to describe method of placement, and frequency and severity of complications associated with a subpalpebral lavage system placed in the medial aspect of the equine inferior eyelid. The inferomedial subpalpebral lavage (ISPL) tube is positioned deep in the medial aspect of the inferior conjunctival fornix so that the footplate lies flat between the lower eyelid and the anterior surface of the nictitans. Retrospective data from the placement of 92 ISPL systems placed in 86 horses during a 31-month period were examined. Tube placement was performed using sedation and regional anesthesia only in 59% of horses. The median duration of tube placement was 19 days (range: 1-61 days). Seventy-one horses were treated for up to 55 days following discharge from hospital with an ISPL tube in place. No complications were reported with 59% of ISPL systems. Non-ocular complications were found in 38% of ISPL systems and included tube displacement from the conjunctival fornix (18%), suture loss requiring resuturing of the system to the horse's head (14%), and damage necessitating replacement of the injection port (6%). Ocular complications were recorded in 3% of horses and were limited to inferior eyelid swelling. Vision was retained in 88% of horses. The ISPL system is easily and safely placed, and well tolerated for extended periods. It appears to be associated with infrequent and minor complications when compared with placement of subpalpebral lavage tubes in the superior eyelid.  相似文献   
982.
OBJECTIVE: To evaluate the effectiveness of a commercially available ELISA kit for detecting antibodies against Borrelia burgdorferi in dogs. SAMPLE POPULATION: Banked sera from 440 military working dogs were used for serologic analyses. PROCEDURE: Serum samples were analyzed for antibodies against B burgdorferi by use of a commercially available ELISA and subsequently by western blot analysis as a confirmatory test. RESULTS: Results from the ELISA indicated that 89 (20%) samples were positive for exposure to B burgdorferi or canine Lyme disease vaccine, and 351 (80%) were negative. Follow-up testing by western blot analysis indicated that results for 109 (25%) samples were positive and 331 (75%) were negative for exposure. All samples that had positive results on the ELISA also had positive results on western blot analysis (true positives). Of the 351 samples that had negative results on the ELISA, only 331 had negative results on western blot analysis (true negatives). The remaining 20 samples had positive results on western blot analysis. By use of a standard 2 x 2 table, it was determined that the ELISA had a sensitivity of 82%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 94%. CONCLUSIONS AND CLINICAL RELEVANCE: The commercial ELISA kit evaluated in this study appeared to lack adequate sensitivity for detecting all potential cases of borreliosis in dogs. The ELISA was also unable to discriminate natural exposure from exposure attributable to vaccination, which could complicate interpretation of positive results and treatment of dogs with clinical signs.  相似文献   
983.
984.
The first European Congress on Agriculturaland Food Ethics was held at Wageningen University andResearch Center (WUR), Wageningen, The Netherlands, March 4–6, 1999. This was the inaugural conference forthe newly forming European Society for Agricultural andFood Ethics – EUR-SAFE – and around two hundredpeople from across Europe (and a handful of NorthAmericans) participated. Following theCongress/conference, a small (16 people), two-dayworkshop funded in part by the US National ScienceFoundation focused on similarities and differencesbetween the US and the EU regarding publicdiscourse/debate on food biotechnology. A briefoverview of the Congress and the follow-up workshopsuggests what lessons AFHVS and ASFS might learn fromEuropean experience of agricultural and food ethics.  相似文献   
985.
A general problem for microbiologists is determining the number of phenotypically similar colonies growing on an agar plate that must be analyzed in order to be confident of identifying all of the different strains present in the sample. If a specified number of colonies is picked from a plate on which the number of unique strains of bacteria is unknown, assigning a probability of correctly identifying all of the strains present on the plate is not a simple task. With Escherichia coli of avian cellulitis origin as a case study, a statistical model was designed that would delineate sample sizes for efficient and consistent identification of all the strains of phenotypically similar bacteria in a clinical sample. This model enables the microbiologist to calculate the probability that all of the strains contained within the sample are correctly identified and to generate probability-based sample sizes for colony identification. The probability of cellulitis lesions containing a single strain of E. coli was 95.4%. If one E. coli strain is observed out of three colonies randomly selected from a future agar plate, the probability is 98.8% that only one strain is on the plate. These results are specific for this cellulitis E. coli scenario. For systems in which the number of bacterial strains per sample is variable, this model provides a quantitative means by which sample sizes can be determined.  相似文献   
986.
The objective of this study was to test whether sourdough could improve quality and delay staling of gluten-free (GF) bread. Three strains of lactic acid bacteria used were Lactobacillus plantarum 2115KW, L. plantarum FST 1.11, and L. sanfranciscensis TMW 1.52, and these were subsequently compared with nonacidified control and chemically acidified sourdoughs, batters, and GF breads. Bread characteristics such as pH, total titratable acidity, and crumb hardness (five-day storage) were evaluated. Extrusion (texture analyzer) measurements showed that the sourdoughs became significantly softer during 24 hr of fermentation (P < 0.001). Both LP 2115KW and LP FST 1.11 strains grew better and produced more acid than LS 1.52. Confocal laser-scanning microscopy also revealed a breakdown in the structure of the sourdoughs over time. Crumb hardness increased significantly for all breads (P < 0.05). After five days of storage, two strains yielded significantly softer bread than the nonacidified control (P < 0.05). This was in distinct contrast to the chemically acidified control that at day 5 was significantly firmer than all other breads (P < 0.05). It was concluded that sourdough improves the delay in staling of GF bread, although the positive effects were smaller than those found in wheat bread.  相似文献   
987.
Internationally, conservation easements are increasingly popular land management tools for private landowners, government agencies and non-governmental organizations seeking to preserve forests and other natural settings. This paper reports a study of the design and use of conservation easements by organizations and public agencies in the USA. More than 355 conservation organizations and 16 state agencies holding at least 3,598 forestland easements were identified. Demonstrated shortfalls in baseline forest inventories, record keeping, and professionally-developed management plans were evident on working forest easements. Failure to address these shortcomings runs the risk of jeopardizing the legitimacy of the easement approach even where favorable legal and tax conditions exist. Management restrictions varied broadly, with a minority of respondents prohibiting such techniques as clearcutting and salvage logging. Concerns for the use of chemicals, best management practices, and streamside management zones were commonly reflected in easement language, whereas logging road design and the cultivation of old-growth conditions remain largely undeveloped. Implications from the US experience, where easements are relatively well-developed, highlights the need for professional forestry advice—particularly for non-industrial or small-scale forest owners—in both easement development and implementation, the need for careful planning, and the need to carefully consider the respective goals of the forest landowners in crafting the easement documents. In the cases of developing nations, consideration of the differing needs of landowners may require increased flexibility in management documents.  相似文献   
988.
ABSTRACT Epicuticular wax on needles was evaluated for its influence on Cronartium ribicola infection of resistant and susceptible selections of Pinus strobus. Environmental scanning electron microscopy comparisons revealed that needles from a resistant selection of eastern white pine, P327, had a significantly higher percentage of stomata that were occluded with wax, fewer basidiospores germinating at 48 h after inoculation, and fewer germ tubes penetrating stomata than needles from a susceptible selection H111. In addition, needles from seedlings that failed to develop symptoms 6 weeks after inoculation, from a cross between P327 and susceptible parent H109, had a significantly higher percentage of stomata occluded with wax compared with needles from seedlings that developed symptoms. In experiments where epicuticular waxes were removed from needles before seedlings were infected, resistant seedlings without wax developed approximately the same number of infection spots (as measured by spot index) as susceptible seedlings with wax intact. Gas chromatography/mass spectrometry comparisons of extracted epicuticular waxes revealed several peaks that were specific to P327 and not found in susceptible H111 suggesting biochemical differences in wax composition. These results implicate the role of epicuticular waxes as a resistance mechanism in P. strobus selection P327 and suggest a role for waxes in reducing spore germination and subsequent infection through stomatal openings.  相似文献   
989.
Objective Determine the effects of matrix metalloproteinases (MMPs)‐2, ‐9, macrophage inflammatory protein‐2 (MIP‐2), tissue inhibitors of matrix metalloproteinase (TIMP)‐1 and ‐2 by immunohistochemical expression in fungal affected and purulonecrotic corneas. Procedure Paraffin‐embedded equine corneal samples; normal (n = 9), fungal affected (FA; n = 26), and purulonecrotic without fungi (PN; n = 41) were evaluated immunohistochemically for MMP‐2, ‐9, MIP‐2, TIMP‐1 and ‐2. The number of immunoreactive inflammatory cells was counted and statistics analyzed. Western blot was performed to detect MMP‐2, MMP‐9, TIMP‐1 and TIMP‐2 proteins. Results Matrix metalloproteinases‐2, ‐9, MIP‐2, TIMP‐1 and ‐2 immunoreactivity was identified in corneal epithelium of normal corneas, and in corneal epithelium, inflammatory cells, keratocytes, and vascular endothelial cells of both FA and PN samples. Inflammatory cell immunoreactivity was significantly higher in FA and PN samples than in the normal corneas. There was positive correlation between MMP‐2 and MIP‐2, MMP‐9 and MIP‐2, and MMP‐9 and TIMP‐1 in inflammatory cell immunoreactivity in FA samples. There was positive correlation between MMP‐9 and MIP‐2, MMP‐9 and TIMP‐2, MIP‐2 and TIMP‐1, and MIP‐2 and TIMP‐2 in inflammatory cell immunoreactivity in PN samples. Western blot confirmed the presence of all four proteins in equine corneal samples. Conclusion Increased immunoreactivity of MMP‐2 and ‐9 in FA and PN samples is indirectly related to MIP‐2 through its role in neutrophil chemo‐attraction. Tissue inhibitors of matrix metalloproteinase‐1 and TIMP‐2 are up‐regulated in equine purulonecrotic and fungal keratitis secondary to MMP‐2 and MMP‐9 expression. The correlation between MMPs ‐2 and ‐9, MIP‐2, TIMPs ‐1 and ‐2 suggests that these proteins play a specific role in the pathogenesis of equine fungal keratitis.  相似文献   
990.
Journal of Pest Science - Thaumastocoris peregrinus is a sap-sucking insect that infests non-native Eucalyptus plantations in Africa, New Zealand, South America and parts of Southern Europe, in...  相似文献   
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