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排序方式: 共有10000条查询结果,搜索用时 46 毫秒
961.
M. M. Sawyer L. L. Williams A. C. Ode n S. N. Giri B. I. Osburn 《Comparative immunology, microbiology and infectious diseases》1993,16(4):281-287
To evaluate arachidonic acid-related immunoregulatory mechanisms during long-term persistent pestivirus infection, we measured plasma contents of leukotriene C4 (LTC4), prostaglandin D2 (PGD2) and their plasma fatty acid (FA) precursor, arachidonic acid (AA), in six lambs with congenital border disease (BD). Significantly elevated average plasma LTC4 during the first half year of life was associated with increased PDG2 when compared to uninfected control lambs. Significantly elevated total plasma esterified AA stores suggest an effective BDV-mediated prostenoid immunostimulation. However, at 1 yr old, prostenoid secretion had fallen to normal (LTC4) or below normal (PGD2) levels. In contrast, there remained significantly elevated plasma esterified AA, present as available substrate for formation of these anti-viral immunoregulatory agents. These results suggested that preventing mobilization of AA from lipid stores for effective immune responses may be a viral strategy of BD virus that is associated with long term border disease effects. 相似文献
962.
Chicory (Cichorium intybus) belongs to plants of the Compositae family accumulating energy in the form of inulin fructan. Chicory, a prebiotic, is a fermentable oligosaccharide and oligofructose that may affect the intestinal mucosal architecture and the electrophysiological parameters. Therefore, this study was conducted to evaluate the effectiveness of adding chicory fructans in feed on the intestinal morphology and electrogenic transport of glucose in broilers. Four hundred, 1 day old broiler chicks were randomly divided into two groups (200 bird per group) for 5 weeks. The dietary treatments were (i) control, (ii) basal diets supplemented with the dried, grinded ground chicory pulp containing inulin (1 kg of chicory/ton of the starter and grower diets). In duodenum, dietary chicory increased the villus height and villus width and villus height to crypt depth ratio (p < 0.05), but the duodenal crypt depth remained unaffected (p > 0.05). However, in jejunum, the villus height, crypt depth and villus height to crypt depth ratio were decreased by dietary chicory compared with control birds (p < 0.05). In ileum, the villus height and villus crypt depth was decreased by dietary chicory supplementation compared with control (p < 0.05), but, the villus height to crypt depth ratio was increased (p < 0.05). Moreover, dietary chicory relatively affected the electrophysiological parameters of the intestine but did not reach significance. The amount of ΔIsc after d ‐glucose addition to the jejunal mucosa was numerically higher for chicory fed birds (19 μA/cm2) than control birds (10 μA/cm2). The percentage of increase in the Isc after d ‐glucose addition (ΔIsc %) was higher for chicory group upto (90%) of the control group. In colon, the actual Isc value and Isc after d ‐glucose addition was numerically higher for chicory fed birds than control birds (p > 0.05). Moreover, the conductance of jejunal and colonic tissues after d ‐glucose addition remained unaffected by the dietary chicory. In conclusion, addition of chicory to broilers diet increased the duodenal villus height, villus width and villus height to crypt depth ratio and decreased the villus height and crypt depth in both jejenum and ileum. Furthermore, dietary chicory relatively modified the small intestinal electrogenic transport of glucose in broilers. 相似文献
963.
Canine anal sac apocrine gland adenocarcinoma (ASAGAC) is an uncommon but highly invasive and metastatic malignancy. Toceranib phosphate (Palladia) is a receptor tyrosine kinase (RTK) inhibitor that targets several members of the split kinase RTK family. These membrane receptors are important for cell cycling, apoptosis and angiogenesis, all of which can contribute to carcinogenesis. The objective of this study was to evaluate archived, paraffin-embedded canine ASAGAC and normal canine anal sacs for immunohistochemical detection of Kit and platelet-derived growth factor receptor beta (PDGFR-β). Two of 77 neoplasms (2.6%) expressed Kit. Fifteen of the neoplasms (19.5%) were positive for PDGFR-β expression. None of the normal canine anal sac epithelium expressed Kit or PDGFR-β. Because of these results, further investigation should be considered to determine the role of RTKs in the clinical course and treatment of canine ASAGAC. 相似文献
964.
Effects of perineural capsaicin treatment on compound action potentials of superior laryngeal nerve afferents in sevoflurane-anesthetized dogs 总被引:1,自引:0,他引:1
Mutoh T Kanamaru A Kojima K Nishimura R Sasaki N Tsubone H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(1):117-120
Effects of perineural capsaicin (CAPS) treatment on compound action potentials of the superior laryngeal nerve (SLN) afferents were studied in 6 sevoflurane-anesthetized dogs. Perineural CAPS (100 microg/ml) to the bilateral SLNs reduced (P<0.01) the peak and integral amplitudes of the C-wave of the compound action potential. By contrast, the perineural CAPS had no effect on the A-wave component (P>0.05). Removal of the perineural CAPS recovered the C-wave to pretreatment level. The perineural CAPS treatment selectively blocks C-wave compound action potentials of the SLN afferents, providing a useful tool for studies of laryngeal C-fibers in respiratory physiology. 相似文献
965.
966.
Rebecca J. Kessler Shelley Rankin Sheri Young Kathleen O'Shea Maria Calabrese Amy Guldin Nicole Lipson Donna A. Oakley Urs Giger 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(1):29-38
Background: While screening programs have reduced the risk of infectious disease transmission by donors in human and veterinary blood banking, bacterial contamination of blood products has emerged as a major complication in human medicine. Objectives: To describe a Pseudomonas fluorescens (Pf)‐contaminated feline packed RBC (pRBC) unit and experimentally investigate Pf‐contaminated canine pRBCs. Methods: Canine pRBCs were inoculated with Pf‐rich pRBCs from the sentinel feline unit and stored at 4°C or 20°C for 72 hours. Aliquots from the pRBCs were serially evaluated by microscopy, culture, and a eubacterial 16S rRNA real‐time PCR assay. Results: One Pf‐contaminated feline unit turned black after 22 days of storage and was removed from the blood bank; a source was not found, and no other contaminated units were identified. Canine pRBCs spiked with 5 or 25 μL of the sentinel unit became culture‐ and/or 16S PCR‐positive at ≥8 hours at 20°C and 48 hours at 4°C and developed a color change at ≥24 hours. Sensitivity studies indicated that without incubation, inoculation of ≥100 μL Pf‐rich pRBCs was necessary for a positive 16S PCR test result. Conclusions: P. fluorescens grows in stored pRBCs slowly at 4°C and rapidly at 20°C. Screening of blood products for color change, estimating bacterial concentration with microscopy, and 16S PCR testing are simple and fast ways to detect bacteria in stored blood. Aseptic collection, temperature‐controlled storage, and regular visual monitoring of stored units is recommended. Discolored units should not be transfused, but examined for bacterial contamination or other blood product quality problems. 相似文献
967.
968.
F Blecha G A Anderson F Osorio S K Chapes P E Baker 《Veterinary immunology and immunopathology》1987,15(3):253-265
A study was conducted to determine the in vivo efficacy of isoprinosine (ISO) in calves infected with bovine herpesvirus type-1 (BHV-1). Calves were infected with BHV-1 on day 0 and received ISO daily for 14 days. Clinical signs of disease, shedding of BHV-1, lymphocyte proliferative responses to mitogens, interleukin-2 production, and alveolar macrophage bactericidal activity were monitored during the study. Rectal temperatures were increased (P less than 0.05) in BHV-1 and ISO-BHV-1 calves at days 3 to 7 postinfection (PI). Isoprinosine did not influence BHV-1 shedding in calves. Lymphocyte proliferative responses to phytohemagglutinin (PHA) were lower (P less than 0.01) in BHV-1 calves when compared to control or ISO calves at day 4 PI, but ISO did not ameliorate this effect. Interleukin-2 activity was greater (P less than 0.05) in ISO-BHV-1 calves on days 4 and 8 PI in PHA-stimulated lymphocytes and on day 8 PI in concanavalin A-stimulated lymphocytes when compared to control, ISO or BHV-1 calves. Isoprinosine treatment of BHV-1-infected calves tended to decrease alveolar macrophage bactericidal activity. These data suggest that ISO does not reverse BHV-1 suppression of lymphocyte proliferation, but may enhance IL-2 production in BHV-1 infected calves. 相似文献
969.
Udder secretions sampled during the summer in 1984 and 1985 from mastitic quarters of 51 non-lactating cattle, mainly heifers less than 2 years of age, were examined bacteriologically for the presence of (facultative) aerobic and obligate anaerobic bacteria (OAB) and by gas-liquid chromatography (GLC) in order to detect volatile fatty acids (VFA), metabolic end-products of OAB. Forty-nine samples yielded positive cultures and in 20 cases these were mixtures of (facultative) aerobes and OAB. Only two specimens appeared to be sterile and from one specimen only were OAB cultured. Corynebacterium pyogenes was isolated from 35% of the cases and Peptococcus indolicus and Fusobacterium necrophorum from 31 and 22%, respectively. In most specimens (19/21) which yielded OAB after culturing, VFA (C3-C6) could be detected by GLC. Detection of VFA in summer mastitis secretions appeared to be a useful technique to evaluate the importance and association of OAB with summer mastitis. Because samples can be easily collected and stored at -20 degrees C, this is especially advantageous in situations where adequate facilities for the isolation of OAB are not readily available. 相似文献
970.
An African Swine Fever virus (ASFV) isolated in an 1983 outbreak of the disease in Piemonte, Italy, was related by restriction endonuclease analysis of the viral genome to ASFV strains isolated in the Dominican Republic (1978), Haiti (1981) and Cameroon (1982). 相似文献