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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
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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
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Jain NC Blue JT Grindem CB Harvey JW Kociba GJ Krehbiel JD Latimer KS Raskin RE Thrall MA Zinkl JG 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1991,20(3):63-82
Blood and bone marrow smears from 49 dogs and cats, believed to have myeloproliferative disorders (MPD), were examined by a panel of 10 clinical pathologists to develop proposals for classification of acute myeloid leukemia (AML) in these species. French-American-British (FAB) group and National Cancer Institute (NCI) workshop definitions and criteria developed for classification of AML in humans were adapted. Major modifications entailed revision of definitions of blast cells as applied to the dog and cat, broadening the scope of leukemia classification, and making provisions for differentiating erythremic myelosis and undifferentiated MPD. A consensus cytomorphologic diagnosis was reached in 39 (79.6%) cases comprising 26 of AML, 10 of myelodysplastic syndrome (MDS), and 3 of acute lymphoblastic leukemia (ALL). Diagnostic concordance for these diseases varied from 60 to 81% (mean 73.3 +/- 7.1%) and interobserver agreement ranged from 51.3 to 84.6% (mean 73.1 +/- 9.3%). Various subtypes of AML identified included Ml, M2, M4, M5a, M5b, and M6. Acute undifferentiated leukemia (AUL) was recognized as a specific entity. M3 was not encountered, but this subclass was retained as a diagnostic possibility. The designations M6Er and MDS-Er were introduced where the suffix "Er" indicated preponderance of erythroid component. Chief hematologic abnormalities included circulating blast cells in 98% of the cases, with 36.7% cases having >30% blast cells, and thrombocytopenia and anemia in approximately 86 to 88% of the cases. Bone marrow examination revealed panmyeloid dysplastic changes, particularly variable numbers of megaloblastoid rubriblasts and rubricytes in all AML subtypes and increased numbers of eosinophils in MDS. Cytochemical patterns of neutrophilic markers were evident in most cases of Ml and M2, while monocytic markers were primarily seen in M5a and M5b cases. It is proposed that well-prepared, Romanowsky-stained blood and bone marrow smears should be examined to determine blast cell types and percentages for cytomorphologic diagnosis of AML. Carefully selected areas of stained films presenting adequate cellular details should be used to count a minimum of 200 cells. In cases with borderline diagnosis, at least 500 cells should be counted. The identity of blast cells should be ascertained using appropriate cytochemical markers of neutrophilic, monocytic, and megakaryocytic differentiation. A blast cell count of > 30% in blood and/or bone marrow indicates AML or AUL, while a count of < 30% blasts in bone marrow suggests MDS, chronic myeloid leukemias, or even a leukemoid reaction. Myeloblasts, monoblasts, and megakaryoblasts comprise the blast cell count. The FAB approach with additional criteria should be used to distinguish AUL and various subtypes of AML (Ml to M7 and M6Er) and to differentiate MDS, MDS-ER, chronic myeloid leukemias, and leukemoid reaction. Bone marrow core biopsy and electron microscopy may be required to confirm the specific diagnosis. Immunophenotyping with lineage specific antibodies is in its infancy in veterinary medicine. Development of this technique is encouraged to establish an undisputed identity of blast cells. Validity of the proposed criteria needs to be substantiated in large prospective and retrospective studies. Similarly, clinical relevance of cytomorphologic, cytochemical, and immunophenotypic characterizations of AML in dogs and cats remains to be determined. 相似文献
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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
6.
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
7.
Phycomyces sporangiophores showl a growth response to a light stimus and an avoidance bending response to a physical barrier. A bluie-light stimnlluts Imninisteredl in conjunction with a barrier interferes with the avoidance bending sponse. This interference begins ifter a latency of abotit 3 minultes atndt continues a period of 4 to 5 minutes. 相似文献
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Andrews GA Smith JE Gray M Chavey PS Weeks BR 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1992,21(2):57-60
An improved serum ferritin assay for canine serum has been developed. It uses two monoclonal antibodies in a sandwich arrangement. Serum ferritin can be determined on undiluted canine sera with this assay. The recovery of ferritin added to canine serum ranged from 98 to 106%, the within-assay coefficient of variability was 3.3 to 4.5%, and the assay-to-assay variability was 9.8 to 10.2%. Serum ferritin from 61 apparently healthy dogs had a geometric mean of 252 ng/ml, with a range of 80 ng/ml to 800 ng/ml. 相似文献
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