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1.
Pilot study of the effect of acemannan in cats infected with feline immunodeficiency virus. 总被引:7,自引:0,他引:7
K M Yates L J Rosenberg C K Harris D C Bronstad G K King G A Biehle B Walker C R Ford J E Hall I R Tizard 《Veterinary immunology and immunopathology》1992,35(1-2):177-189
Acemannan, a complex carbohydrate shown to stimulate interleukin-1, tumor necrosis factor alpha and prostaglandin E2 production by macrophages, has also demonstrated antiviral activity in vitro against human immunodeficiency virus, Newcastle disease virus and influenza virus. A pilot study was undertaken to determine acemannan's effect in 49 feline immunodeficiency virus (FIV) infected cats with clinical signs of disease (Stage 3, 4 or 5), 23 of which had severe lymphopenia. Cats received acemannan either by intravenous (Group 1) or subcutaneous (Group 2) injection once weekly for 12 weeks, or by daily oral (Group 3) administration for 12 weeks. Upon entry into the study, cats were randomly assigned to one of the three groups. Laboratory analyses were performed at the beginning of the study and at Weeks 6 and 12. Cats were allowed to continue with a predetermined maintenance regimen of acemannan after completing the 12-week study. Thirteen cats died during the course of treatment. Upon necropsy, the most frequent histopathologic findings were neoplastic, kidney and pancreatic disease. Friedman's two-way ANOVA test showed no significant differences in efficacy among groups administered acemannan by the different routes. Therefore, groups were combined and a signed-ranks test was used to determine changes over time. A significant increase was seen in lymphocyte counts (P < 0.001). Neutrophil counts decreased significantly (P = 0.007), as did incidence of sepsis (P = 0.008). When cats entering with lymphopenia were analyzed separately, a much greater increase in lymphocyte counts was noted (235%) compared with non-lymphopenic cats (42%). A survival rate of 75% was found for all three groups. Thirty-six of 49 animals are alive 5-19 months post-entry. These results suggest that acemannan therapy may be of significant benefit in FIV-infected cats exhibiting clinical signs of disease. 相似文献
2.
B Mermer P Hillman R Harris T Krogmann Q Tonelli W Palin P Andersen 《Veterinary immunology and immunopathology》1992,35(1-2):133-141
We have developed an antibody detection enzyme-linked immunosorbent assay (ELISA) for the identification of animals infected by feline immunodeficiency virus (FIV). The ELISA solid-phase antigen consists of recombinant FIV gag proteins expressed in bacteria. The proteins are purified from bacterial lysates as insoluble inclusion bodies. In the case of bacterially expressed p24gag, it is shown that all of the linear, sequential epitopes presented by viral p24 during infection are retained. Purified preparations can be substituted for solid-phase whole virus in the IDEXX PetChektm immunoassay. The antibody ELISA duplicates the sensitivity and specificity of the whole virus based PetChek plate assay. 相似文献
3.
Pharmacokinetic evaluation of ceftiofur in serum, tissue chamber fluid and bronchial secretions from healthy beef-bred calves. 下载免费PDF全文
S L Halstead R D Walker J C Baker R E Holland G E Stein J G Hauptman 《Canadian journal of veterinary research》1992,56(4):269-274
Ceftiofur is a new broad spectrum cephalosporin marketed for the treatment of acute bovine respiratory disease. In this investigation ceftiofur was administered by intramuscular injection, at 24 h intervals, to healthy beef-bred calves for four days at dosages of 2.2 and 4.4 mg/kg of body weight, with 4 wk intervals between dosing regimens. Serum, tissue chamber fluid (TCF), and bronchial secretion (BS) concentrations of ceftiofur were measured by microbiological assay after the first and fourth dose of each dosing regimen. Peak serum concentrations (Cmax) of 8.8 micrograms/mL and 17.3 micrograms/mL were obtained approximately 2 h (Tmax), the time of mean peak concentration) after single injections of 2.2 mg/kg and 4.4 mg/kg, respectively. The Cmax was increased approximately twofold following multiple doses of 2.2 mg/kg (Cmax = 13.1 micrograms/mL) and 4.4 mg/kg (Cmax = 24.1 micrograms/mL). Ceftiofur accumulated slowly into TCF and peak concentrations were found to be approximately 14% of those observed in serum after the first dose and approximately 24% after multiple dosing. Concentrations of ceftiofur in BS were obtained rapidly with peak concentrations reaching 45% of the serum Cmax after the first dose. After multiple dosing the Cmax for BS was approximately 25% of the serum Cmax. This study found that both the 2.2 mg/kg and 4.4 mg/kg dosing regimens resulted in continuous serum, TCF and BS concentrations of ceftiofur that exceeded the minimal concentration required to inhibit the bacteria most frequently isolated from calves with acute bovine respiratory disease. 相似文献
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P.A. Harris 《Research in veterinary science》1993,54(3):179
The effect of feeding diets with low, adequate and high sodium contents on plasma aldosterone concentrations in horses and ponies was evaluated using human immunoassay kits. The effect of moderate to high intensity exercise of up to six minutes duration on plasma aldosterone concentrations in three thoroughbred- horses was also investigated. On an adequate sodium diet plasma aldosterone concentrations increased to a peak around four hours after feeding. Little daily variation was found in the pre-feeding aldosterone concentrations over three days. Feeding additional salt resulted initially in no increase in plasma aldosterone concentrations in three out of four animals. After five days all four animals had lower pre-feeding concentrations, an increase in the magnitude of the response to feeding but a decreased rise in absolute concentration. Feeding a diet with a decreased sodium content for several months did not result in a consistent change in the pre-feeding aldosterone concentrations although there were times when all three animals showed an increase in the magnitude of the aldosterone response to feeding. No correlation between changes in the fractional electrolyte excretion values determined and alterations in aldosterone response was found. Exercise resulted in a marked increase in aldosterone concentrations. The expected biological response to feeding and exercise was demonstrated with an acceptable level of reproducibility and repeatability. Samples had similar values when assayed by either of the kits evaluated. 相似文献
7.
Stein T Martineau GP Morris R Charette R 《The Canadian veterinary journal. La revue veterinaire canadienne》1987,28(6):355-362
It is proposed that just as the stethoscope and thermometer are fundamental tools for individual medicine, production and health recording systems are fundamental tools for effective population medicine. Treatment and control of clinical diseases as the primary objective is no longer considered appropriate for livestock population. Disease in populations now describes a deviation between what is happening and what is expected to happen. This redefinition of disease implies that it is of multifactorial origin and thus a different problem solving approach must be implemented. Therefore, a swine enterprise must be considered as a system, a set of interdependent components continuously interacting to produce pork. As a system, it is characterized by certain properties: change, environment, counterintuitive behavior, drift to low performance, interdependency, and organization. A redefinition of diseases implies also that they are not only “treated” but managed. Management consists of planning, monitoring, evaluation, and analysis. For this process to be implemented successfully, a goal-directed recording system providing a farm-based infrastructure for problem solving is essential. Clinical problem solving (diagnosis) is thus based on epidemiological and demographic methods. 相似文献
8.
The histomorphologic and immunohistochemical features of chordoma in 20 ferrets were evaluated. The mean age was 3.4 years, and, in the cases for which sex was known, females (n = 10) outnumbered males (n = 5) two to one. All 20 tumors occurred on the tip of the tail. Nineteen of 20 tumors (95%) were composed of three tissue components, often arranged concentrically with lobules of physaliferous cells at the periphery, trabecular bone in the center, and cartilage in between. The bone often contained marrow and hematopoietic cells. One tumor lacked chondromatous or osseous tissue. Immunohistochemical results were consistent with previous studies of chordoma. All 20 tumors (100%) were positive for keratin and vimentin intermediate filaments; 15 (75%) were positive for S-100 protein; and 17 (85%) were positive for neuron specific enolase. This neoplasm shares morphologic and immunohistochemical features with "classic," as well as chondroid chordoma, of human beings, making it a potential animal model. 相似文献
9.
Six shipments totaling 3452 mummies of the blackmargined aphid,Monellia caryella (Fitch), parasitized withAphelinus perpallidus Gahan, were obtained by air freight during the years 1982-1985 from Texas A&M Research Center, El Paso, Texas. About two-thirds of the mummies did not yield parasites. A colony ofA. perpallidus was established in the laboratory. Under laboratory conditions the percentage of emerged parasites was higher than that in the imported mummies, and the parasite had very limited impact on the aphid population. Field releases of the parasite were made but no establishment ofA. perpallidus was observed through the years. 相似文献
10.
Curtis RA Viel L McGuirk SM Radostits OM Harris FW 《The Canadian veterinary journal. La revue veterinaire canadienne》1986,27(4):170-172
The purpose of this paper is to emphasize the importance of pulmonary auscultation for the clinician. It suggests a clarification and simplification of the terminology to be used which would be helpful to veterinary students and allow better communications between veterinarians. The interpretation of these sounds and the relationships to conditions and diseases of the lungs in cattle, horses, sheep and goats are discussed. 相似文献