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1.
Newcastle disease virus (NDV) has antineoplastic and immunostimulatory properties, and it is currently being clinically tested in anticancer therapy. In order to analyse the immunostimulatory effects of NDV on bovine papillomatosis, we inoculated 14 cows subcutaneously with an attenuated vaccine containing the LaSota strain of NDV (LS-NDV). Four cows with papillomatosis served as controls. Serum samples were collected from each animal 1 h preinoculation and 7 and 21 days postinoculation. In inoculated cows on days 7 and 21, the mean antibody titres were log2 2.43 ± 0.92 and 5.57 ± 0.72, respectively, by haemagglutination inhibition, and the mean levels of TNFα were 5.80 ± 4.19 and 5.39 ± 2.66 ng/mL, respectively, by WEHI-164 cytotoxicity assay. Significant differences between inoculated and control animals were evident for antibody titres on day 21 and clinical scores on day 60. A correlation was evident between the TNFα activities and clinical scores on day 21. The clinical observations at day 60 showed that the papillomas in five cows had completely resolved (36%), one animal had no alterations on clinical appearance of the tumour (7%), and papillomas in eight cows had regressed (57%). In conclusion, these results demonstrated that inoculation of LS-NDV vaccine stimulates an antibody response and a limited increase in TNFα activity and may enhance clinical recovery in bovine papillomatosis.
Funding: Scientific Research Council of Akdeniz University.  相似文献   
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BackgroundPrevious studies evaluating the accuracy of computed tomography (CT) in detecting caudal vena cava (CVC) invasion by adrenal tumors (AT) used a binary system and did not evaluate for other vessels.ObjectiveTest a 7‐point scale CT grading system for accuracy in predicting vascular invasion and for repeatability among radiologists. Build a decision tree based on CT criteria to predict tumor type.MethodsRetrospective observational cross‐sectional case study. Abdominal CT studies were analyzed by 3 radiologists using a 7‐point CT grading scale for vascular invasion and by 1 radiologist for CT features of AT.AnimalsDogs with AT that underwent adrenalectomy and had pre‐ and postcontrast CT.ResultsNinety‐one dogs; 45 adrenocortical carcinomas (50%), 36 pheochromocytomas (40%), 9 adrenocortical adenomas (10%) and 1 unknown tumor. Carcinoma and pheochromocytoma differed in pre‐ and postcontrast attenuation, contralateral adrenal size, tumor thrombus short‐ and long‐axis, and tumor and thrombus mineralization. A decision tree was built based on these differences. Adenoma and malignant tumors differed in contour irregularity. Probability of vascular invasion was dependent on CT grading scale, and a large equivocal zone existed between 3 and 6 scores, lowering CT accuracy to detect vascular invasion. Radiologists'' agreement for detecting abnormalities (evaluated by chance‐corrected weighted kappa statistics) was excellent for CVC and good to moderate for other vessels. The quality of postcontrast CT study had a negative impact on radiologists'' performance and agreement.Conclusions and Clinical ImportanceFeatures of CT may help radiologists predict AT type and provide probabilistic information on vascular invasion.  相似文献   
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If soil communities rely on plant-derived carbon, is biodiversity lost when this primary source is removed? Soil microbial and mesofaunal communities at the Rothamsted Highfield site were compared under a mixed grass sward, arable rotation and a section maintained as a bare-fallow for the past 50 years by regular tillage. Organic matter reserves have been degraded and microbial and mesofaunal numbers and mite diversity have declined in this unique bare-fallow site, where fresh carbon inputs have been drastically reduced. However, it supports a species-rich metabolically active bacterial community of similar diversity to that in soil maintained as grass sward. Thus in contrast to soil mesofauna, bacterial diversity (but not abundance) is apparently independent of plant inputs.  相似文献   
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Yield levels in smallholder farming systems in semi-arid sub-Saharan Africa are generally low. Water shortage in the root zone during critical crop development stages is a fundamental constraining factor. While there is ample evidence to show that conservation tillage can promote soil health, it has recently been suggested that the main benefit in semi-arid farming systems may in fact be an in situ water harvesting effect. In this paper we present the result from an on-farm conservation tillage experiment (combining ripping with mulch and manure application) that was carried out in North Eastern Tanzania from 2005 to 2008. Special attention was given to the effects of the tested treatment on the capacity of the soil to retain moisture. The tested conservation treatment only had a clear yield increasing effect during one of the six experimental seasons (maize grain yields increased by 41%, and biomass by 65%), and this was a season that received exceptional amounts of rainfall (549 mm). While the other seasons provided mixed results, there seemed to be an increasing yield gap between the conservation tillage treatment and the control towards the end of the experiment, and cumulatively the yield increased with 17%. Regarding soil system changes, small but significant effects on chemical and microbiological properties, but not on physical properties, were observed. This raises questions about the suggested water harvesting effect and its potential to contribute to stabilized yield levels under semi-arid conditions. We conclude that, at least in a shorter time perspective, the tested type of conservation tillage seems to boost productivity during already good seasons, rather than stabilize harvests during poor rainfall seasons. Highlighting the challenges involved in upgrading these farming systems, we discuss the potential contribution of conservation tillage towards improved water availability in the crop root zone in a longer term perspective.  相似文献   
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Extract

Evidence that feeding massive doses, of calciferol prior to calving may be a useful method of preventing milk fever was obtained by Hibbs and co-workers (1950, 1951) at Ohio State University. The treatment causes a rise in serum calcium and if dosing is suitably timed the post-partum fall in serum calcium may be countered, thus making up for the presumed parathyroid failure which occurs at this lime and which is believed by many to be the underlying cause of milk fever.  相似文献   
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The bioavailability of rafoxanide was compared after intraruminal and intra-abomasal administration in healthy adult sheep (n = 6) in a single dose, 2 parallel group study at 7.5 mg/kg. Rafoxanide concentrations in plasma were measured by means of HPLC analysis. Primary pharmacokinetic parameters for bioavailability and disposition of rafoxanide in plasma for both routes of administration were determined by non-compartmental and non-linear, 1-compartmental pharmacokinetic analysis, respectively. Significantly (P < or = 0.05) higher peak plasma concentrations (c(max)) of rafoxanide and a more rapid rate of absorption (c. 3.5 times) was observed in sheep after intra-abomasal (i-a) administration compared to intraruminal (i.r.) administration. A significantly (P < or = 0.05) longer lag period (t(lag)) before absorption (6.8 +/- 2.9 h) occurred after i.r. than after i-a treatment (1.9 +/- 0.6 h). There was no significant difference (P > 0.05) in AUC, MRT and in the rates of elimination (k10-HL and t(1/2beta)) between the i.r. and i-a routes of administration. The results of the study demonstrated the important influence of the rumino-reticulum on absorption of rafoxanide in sheep.  相似文献   
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Cryptosporidiosis is an enteric disease of animals and humans that can be fatal in immunocompromised individuals. There is no known effective treatment for cryptosporidiosis. Bilbies are threatened marsupials and are bred in captivity as part of a recovery program to re-introduce this species to the southwest of Western Australia. Cryptosporidium muris infection was detected in the faeces of bilbies at a captive breeding colony. Stress associated with a high density of bilbies in enclosures may have predisposed some of the bilbies to infection with C. muris. C. muris has been described in mice and was found in the faeces of one mouse trapped in the breeding enclosures. It is likely the bilbies acquired the infection from mice by faecal contamination of food and water. The infection cleared within 2 months from some bilbies, however others remained infected for 6 months and treatment was attempted with dimetridazole. Subsequently the parasite was no longer be detectable in the faeces.  相似文献   
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The efficacy of 5 drugs was tested against experimental Babesia felis infection in domestic cats. Two of the drugs, rifampicin and a sulphadiazine-trimethoprim combination, appeared to have an anti-parasitic effect, but were inferior to primaquine. The other 3 drugs, buparvaquone, enrofloxacin and danofloxacin, had no significant anti-babesial effect.  相似文献   
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