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991.
992.
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   
993.
Introduction: Palliative therapy is essential to improve the quality of life of dogs with osteosarcoma (OSA), when definitive therapy is not considered a valid option. Bisphosphonates, a novel class of antiosteoclastic drugs, are widely used in humans for several painful osteolytic conditions. Dual energy x‐ray absorptiometry (DEXA) is recognized as a reliable tool to measure bone mineral density (BMD), and to monitor treatment response to bisphosphonates in humans. A prospective evaluation of pamidronate, an injectable aminobisphosphonate, is ongoing in dogs with appendicular OSA. The potential value of DEXA for objective evaluation of BMD variations with palliative therapies is concurrently being assessed. Materials and Methods: Dogs with naturally occurring appendicular OSA treated with pamidronate constitute the patient population. A DEXA scan (QDR‐4500 W, Hologic, Bedford, MA) is performed on day 0 (baseline) and on every treatment day with pamidronate thereafter (every 28 days). For each dog, a whole body scan is performed, followed by a scan of the tumor, and contralateral normal bone. Three regions of interest are subsequently analyzed for BMD changes in tumor and normal bone. Statistical analysis was performed using Student t‐test and paired t‐tests, with significance being set at p < 0.05. Results: Nineteen dogs have been enrolled to date. Seven responders and 6 non‐responders have suitable data for analysis. A significant difference is observed (p = 0.04) between tumor BMD variations of responders and non‐responders at day 28 (mean variations +18.0% and ?4.6% respectively). The changes at day 28 are significant only in the responders (p = 0.038 vs p = 0.05 in non‐responders). When BMD of tumor and normal bone at day 84 is compared to day 0 in six responders, only tumor had a significant increase (p = 0.017 vs p = 0.279, respectively). Conclusions: Objective measurements of response to therapy are essential in pain palliation studies. Increased tumor bone BMD, as obtained by DEXA analysis, may correlate with subjective clinical improvement in pamidronate‐treated dogs with appendicular OSA.  相似文献   
994.
The cumulative cardiotoxicity that occurs as a result of doxorubicin chemotherapy is irreversible and can affect both quality and quantity of life for the cancer patient. Cardiac troponin I (cTnI) is a sensitive and specific marker of cardiomyocyte death. The purpose of this retrospective study was to evaluate serum concentrations of cTnI in dogs with lymphoma or osteosarcoma given doxorubicin chemotherapy, and with known cardiac outcome, based on a minimum assessment by physical examination and thoracic radiography. Serum samples were also available for cTnI measurement from seven healthy dogs given intracoronary doxorubicin. Serial serum samples obtained before, during and after doxorubicin chemotherapy showed increased cTnI concentrations in some clinical patients following chemotherapy (P = 0.0083 compared to baseline), but this did not correlate with clinical signs of cardiomyopathy. In dogs that subsequently developed cardiomyopathy however, serum cTnI concentrations were elevated before clinical signs became evident (confirmed with echocardiography).  相似文献   
995.
A computer program (CalcAnesth) was developed with Visual Basic for the purpose of calculating the doses and prices of injectable medications on the basis of body weight or body surface area. The drug names, concentrations, and prices are loaded from a drug database. This database is a simple text file, that the user can easily create or modify. The animal names and body weights can be loaded from a similar database. After typing the dose and the units into the user interface, the results will be automatically displayed. The program is able to open and save anesthetic protocols, and export or print the results. This CalcAnesth program can be useful in clinical veterinary anesthesiology and research. The rationale for dosing on the basis of body surface area is also discussed in this article.  相似文献   
996.
The purpose of this retrospective study was to evaluate six cases of equine sarcoidosis for initial presenting symptoms, response to therapy and actual outcome. Dermatologists and dermatopathologists from Europe, the United States, Australia and Canada were contacted to obtain these six cases, as this is a rare disease. Signalment, clinical signs, histological findings, clinical management and outcome were determined via a questionnaire and compared to former reports. There was no age or breed predilection, and four of six horses were geldings. Age of onset ranged from 3 months to 17 years. Onset of the disease was insidious or rapid. Interestingly, in five of six cases, scaling began on the trunk (girth and shoulder). Scaling, crusting and alopecia were seen in all six horses. In one horse, clinical signs of systemic disease were reported and included intermittent fever, prescapular lymphadenopathy, depression, poor body condition and nasal discharge. Treatment included phenylbutazone, deworming agents, antibiotics, short‐term low‐dose corticosteroids, and 1–1.5 mg/kg of prednisolone. One horse showed a partial response to trimethoprim and sulfonamide, and five of six went into clinical remission with corticosteroid treatment. Five of six horses were still alive 1 year after diagnosis; one horse was diagnosed <12 months ago. Two horses are in complete remission 4 and 8 years after diagnosis. In both horses, clinical signs recurred after cessation of therapy and went into remission again with reintroduction of treatment. Both of these horses have been in remission for several years without therapy. Funding: Self‐funded.  相似文献   
997.
The aim of these experiments was to investigate the potential antiviral effect of Saccharomyces cerevisiaeβ‐glucan on the pneumonia induced by swine influenza virus (SIV). Forty colostrum‐deprived 5‐day‐old piglets were randomly divided into four groups of 10. The 20 pigs in groups 1 and 2 were administered Saccharomyces cerevisiaeβ‐glucan orally (50 mg/day/pig; En‐Bio Technology Co., Ltd) for 3 days before SIV infection and those in groups 3 and 4 were given culture medium/diluent alone. Groups 1 and 3 were inoculated intranasally with 3 ml of tissue culture fluid containing 2 × 106 tissue culture infective doses 50% (TCID50)/ml of SIV and those in groups 2 and 4 were exposed in the same manner to uninfected cell culture supernatant. The microscopic lung lesions induced by SIV infection (group 1 pigs) were significantly more severe than those induced by infection in animals pre‐administered β‐glucan (group 3) (P < 0.05). Significantly more SIV nucleic acid was detected in the lungs of pigs experimentally infected with SIV only (group 1) at 5, 7 and 10 days post‐inoculation (dpi) compared with lungs from pigs pre‐administered β‐glucan and infected with SIV (group 3) (P < 0.05). The concentrations of interferon‐γ (IFN‐γ) and nitric oxide (NO) in bronchoalveolar lavage fluid from pigs pre‐administered β‐glucan and infected with SIV (group 3) were significantly higher than for any other group at 7 and 10 dpi for IFN‐γ, and at 5, 7 and 10 dpi for NO (P < 0.05). Saccharomyces cerevisiaeβ‐glucan reduced the pulmonary lesion score and viral replication rate in SIV‐infected pigs. These findings support the potential application of β‐glucan as prophylactic/treatment agent in influenza virus infection.  相似文献   
998.
A perspective on the measurement of time in plant disease epidemiology   总被引:2,自引:1,他引:2  
The growth and development of plant pathogens and their hosts generally respond strongly to the temperature of their environment. However, most studies of plant pathology record pathogen/host measurements against physical time (e.g. hours or days) rather than thermal time (e.g. degree-days or degree-hours). This confounds the comparison of epidemiological measurements across experiments and limits the value of the scientific literature.  相似文献   
999.
As a first step in the development of a mycoherbicide for biological control of Cirsium arvense indigenous fungal pathogens that had been isolated from diseased hosts were tested both singly and in combination on potted plants under environmental conditions. Disease symptoms (necroses, chloroses and macerations) and parameters of growth and development were evaluated to determine the potential for weed control. During 1998, Phoma destructiva, Phoma hedericola, a Mycelia sterilia and Puccinia punctiformis were inoculated singly. With the exception of the obligate biotroph P. punctiformis (local infections), the single inoculations reduced the measured parameters. A combined inoculum of P. punctiformis and Ph. hedericola was less effective than Ph. hedericola alone. In 1999, Ph. hedericola, Ph. destructiva, Ph. nebulosa and the Mycelia sterila were applied both singly and as a combined inoculum. Of all the tested inocula, the mixture of four pathogens had the greatest potential for biocontrol, significantly reducing reproductive capacity of the plants. These results demonstrate the importance of taking advantage of synergisms in developing a mycoherbicide.  相似文献   
1000.
As field sampling is time consuming, it is necessary to develop efficient sampling techniques to obtain accurate estimates of the weed seedbank in soil. The relative efficiency between sampling schemes depends on the spatial variability in weed seed density across agricultural fields. Spatial variability of the weed seed density was characterized by theoretical correlograms. A systematic sampling (square grill) scheme was considered and it was found that, taking into account spatial variability, this sampling scheme was more efficient than simple random sampling. As a result, the sample size can be reduced in comparison with that given in previous studies, where spatial correlation was ignored. The reduction depends on the correlation structure defined as a function of the ratio, τ, between the nugget effect and the sill of the variogram. The maximum reduction of the sample size, without loss of either precision or confidence level corresponds to the case where there is no nugget effect, τ = 0. The opposite extreme case, where the reduction is nil, corresponds to the case of a pure nugget effect τ = 1. The abaci based on given expressions are provided to determine the sample size in species whose spatial pattern can be fitted either to a Poisson or to a negative binomial distribution.  相似文献   
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