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991.
Immunogenic and protective effects of a DNA vaccine for Mycobacterium marinum in fish 总被引:3,自引:0,他引:3
Mycobacteriosis, caused by numerous Mycobacterium spp., can be a devastating disease of both wild and cultured fishes. As no efficacious treatment exists, a vaccine against fish mycobacteriosis is essential for prevention and control of this disease. Thus, a DNA vaccine was constructed using the Mycobacterium marinum Ag85A gene that encodes one of the major secreted fibronectin-binding proteins of Mycobacterium spp., which was isolated and then subcloned into a commercially available eukaryotic expression vector. Juvenile hybrid striped bass (Morone saxatilis x M. chrysops), a species known to be particularly susceptible to this disease, were immunized by i.m. and i.p. injection with the resulting construct and as a result produced specific immune responses towards the Ag85A. Increasing concentrations of humoral antibodies to the Ag85A antigen were generated in all DNA vaccine groups, while macrophage phagocytosis and respiratory burst functions failed to exhibit upregulation after vaccination. In addition, fish receiving the DNA vaccine developed a protective response to a live M. marinum challenge 90 days post-inoculation, as demonstrated by increased survival of vaccinated fish over control fish and by reduced splenic bacterial counts in vaccinated fish. Furthermore, humoral immune responses and protective effects were significantly increased at higher vaccine doses using the i.m. injection route. 相似文献
992.
Griffon DJ Stoller A Schaeffer DJ Seddighi MR Johnson AL Kurath P 《Veterinary surgery : VS》2005,34(3):223-230
OBJECTIVE: To evaluate the effect of 2 cement augmentation techniques on pullout strength of 1.5 mm screws placed in stripped 1.5 mm screw sites in the distal metaphysis of feline radii. STUDY DESIGN: Experimental study. SAMPLE POPULATION: Feline radii (21 pairs). METHODS: Treatment groups (n=4) were allocated according to a Latin square design to 4 sites in each pair of radii. Positive and negative controls were a 1.5 mm screw and a screw of the same diameter in a previously stripped screw hole, respectively. Treatment groups were a 1.5 mm screw implanted in a previously stripped screw hole after injection of polymethylmethacrylate (PMMA) or a bioresorbable calcium phosphate cement (CPC, Norian skeletal repair system (SRS)). The ultimate pullout strength was compared between groups. RESULTS: The mean (+/-SEM) pullout strength of screws augmented with either bone cement was less than that of the positive control group and greater than that of the negative control. Injection of CPC or PMMA before screw implantation increased the pullout strength of the negative control by 86.8+/-22.9% and 104.1+/-32.1%, respectively. Holding power of the positive control screws differed from these 2 groups, and was 274.8+/-39.17% higher than that of the negative control. CONCLUSION: Injection of CPC or PMMA increases but does not restore the holding power of stripped 1.5 mm diameter screws. CLINICAL RELEVANCE: The use of CPC (Norian SRS) augmentation of stripped 1.5 mm diameter screws warrants clinical investigation as it combines biomechanical results similar to PMMA with osteoconduction and resorbability. 相似文献
993.
Veterinary clients often seek the same new and innovative cancer treatment options for their companion animals that they read about in the press or on the Internet. It is, therefore, necessary for the practitioner to have an understanding of the development of new and innovative cytotoxic drugs and delivery techniques. This article describes the drug development process and how a new product eventually finds its way into clinical use. Some of the newer drugs and delivery techniques applied to small animals are reviewed. 相似文献
994.
Two wild oat herbicides, benzoylprop-ethyl and flamprop-methyl were administered to lactating cows at low dose levels (0.3–3.0 mg/kg in total diet) and the excretion of total metabolites in milk, urine and faeces was measured. Total residues in tissues were also determined. Similarly a third and related herbicide flamprop-isopropyl was fed to cows, pigs and hens (at 0.5 mg/kg in total diet) and the residues were determined in excreta and tissues, including eggs. The amounts of the compounds fed were equivalent to approximately 10–300 times the total residue found in cereal treated in the field. Residues in milk in most cases were well below 0.001 mg/kg; in muscle samples <0.003 mg/kg; and in eggs, 0.0008 mg/kg, decreasing by 50% in approximately 3 days to 0.0001 mg/kg 4 days after the termination of treatment. Elimination of the herbicides from the animals was rapid in every case and this, together with the low residue levels, was attributed to very efficient metabolic de-esterification to the parent carboxylic acid metabolites (benzoylprop and flamprop). These metabolites possess physical properties ideally suited for excretion via the kidneys and bile into urine and faeces and, conversely, unsuited for transport into milk and eggs. 相似文献
995.
Summary For the past five years a herd of work oxen, now numbering some 450 individuals, has been maintained under the protection of trypanocidal drugs on a settlement scheme in an area of western Ethiopia infested with tsetse. This paper describes the environmental conditions and the epizootiology of trypanosomiasis in the oxen and in the vector, Glossina morsitans. It is concluded that with the strategic use of drugs, oxen can be kept alive and perform useful agricultural work, in areas of high tsetse challenge, provided reasonable standards of veterinary supervision and management are maintained.
El Uso Exitoso De Bueyes En El Desarrollo Agricola De Tierras Infestadas De Tsetse En Etiopia
Resumen Se ha mantenido un número aproximado de 450 bueyes, bajo el efecto de drogas contra la tripanosomiasis (quimioprofiláxis), en una concentración rural bajo el flagelo de la mosca tsetse, en el oeste de Etiopía. Este trabajo describe las condiciones ambientales y epizootiológicas de la tripanosomiasis en bueyes y vectores (Glossina morsitans). Se concluye, que el uso estrátegico de drogas preventivas proteje a los bueyes en áreas infestadas por tsetse, siempre y cuando se mantenga una supervisión veterinaria y de manejo animal aceptable.
Succes De L'Utilisation Des Boeufs De Travail Dans Le Developpement De L'Agriculture D'Une Region D'Ethiopie Infestee De Tse-Tse
Résume Au cours des cinq dernières années, un troupeau de boeufs de travail, maintenant au nombre de quelque 450 têtes, a été maintenu sous protection de produits trypanocides à l'occasion d'un essai d'implantation du bétail dans une région de l'Ouest de l'Ethiopie infestée de tsé-tsé. Ce document traite des conditions de l'environnement, de l'épizootologie des trypanosomoses du bétail ainsi que du vecteur:Glossina morsitans. La conclusion est qu'avec l'utilisation des trypanocides, les boeufs peuvent vivre et donner les performances habituelles au niveau des travaux agricoles dans les zones à haute infestation glossinaire pourvu du'un encadrement vétérinaire et de gestion suffisant soit maintenu.相似文献
996.
Two new sulfur-containing pyrimidine nucleotides have been isolated from hydrolyzates of Escherichia coli transfer RNA. The structures, 2-thiocytosine and 5-methylaminomethyl-2-thiouracil, have been assigned to the bases as a result of study of ultraviolet and mass spectra. An acid-degradation product, S-methylamino-methyluracil, has been synthesized and is identical to that derived from the natural product. 相似文献
997.
998.
David A. M. Watkins 《Pest management science》1976,7(2):184-192
Some properties, analysis and transformations by plants, animals, soil and light of benomyl, carbendazim, thiabendazole, fuberidazole, cypendazole and fenazaflor are discussed. 相似文献
999.
1000.
Deborah A. O''Keefe DVM MS David J. Schaeffer PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1992,6(5):276-282
The hematologic toxicity of doxorubicin, 30 mg/m2 body surface area (BSA) every 21 days to a cumulative dose of 300 mg/m2, was evaluated in six cats. Complete blood and platelet counts were performed daily during the first treatment cycle. They were monitored before treatment for all remaining cycles, and at the average neutrophil nadir (day 8) starting with cycle 4. Significant poikilocytosis developed after the first treatment and remained throughout the study, although anemia did not occur. No other red blood cell abnormalities were seen. Platelet counts remained within the reference range throughout the first treatment cycle, but mild thrombocytopenia (88,000-288,000/uL) was found in 11.3% of subsequent complete blood counts (CBCs). Thrombocytosis was seen in 30.9% of CBCs. Neutropenia did not occur during the first treatment cycle although neutrophil counts did decrease, with the nadir occurring between days 8 and 11. All neutrophil counts returned to pretreatment values by day 14. Neutropenia was documented after 14 of 46 (30.4%) doxorubicin treatments, and was associated with fever in 5 cats (10.9%). All fevers responded to oral antibiotic therapy. Neutropenia that lasted more than 14 days developed in two cats, necessitating dosage reduction to 25 mg/m2 BSA. At the dose used in this study, doxorubicin administration was associated with acceptable hematologic toxicosis in most cats. 相似文献