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11.
Abstract: A 14‐year‐old spayed American Paint mare was evaluated for mild colic, anorexia, pyrexia, and pancytopenia. Physical examination revealed mild tachycardia, tachypnea, and pale mucous membranes. Serial laboratory analyses revealed progressive pancytopenia, hyperfibrinogenemia, and hyperglobulinemia. A few large atypical cells were observed in peripheral blood smears. Results of tests for equine infectious anemia and antipenicillin antibody were negative. Serum protein electrophoresis indicated a polyclonal gammopathy. Smears of bone marrow aspirates contained hypercellular particles, but cell lines could not be identified because the cells were karyolytic, with pale basophilic smudged nuclei and lack of cellular detail. A diagnosis of bone marrow necrosis was made. Treatment consisted of antimicrobials, nonsteroidal anti‐inflammatory drugs, and corticosteroids. The pyrexia resolved; however, the pancytopenia progressively worsened and petechiation and epistaxis developed. The horse was humanely euthanized. Postmortem examination revealed a diffuse round cell neoplasm infiltrating the kidneys, spleen, lymph nodes, lungs, and bone marrow. Immunophenotyping results (CD3+, CD79α−) indicated the neoplastic cells were of T‐cell lineage. Infiltration of lymphoma cells into the bone marrow appeared to have resulted in severe myelophthisis and bone marrow necrosis. Bone marrow necrosis has been associated previously with lymphoma in humans and dogs. To our knowledge, this is the first reported case of lymphoma resulting in bone marrow necrosis in a horse.  相似文献   
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Journal of General Plant Pathology - Viruses that infect Ranunculus asiaticus L., a globally important greenhouse ornamental, have consistently caused serious damage in Japan. We coupled...  相似文献   
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1. A study was conducted to characterise the development of amino acid transport in broiler chicks, using L-tryptophan as a model. The chicks were maintained on a broiler starter diet between hatch and 21 d of age. 2. There was a significant reduction in the rate of uptake of 0.04 mM L-tryptophan with age in both the jejunum and ileum. Uptake was enhanced in the presence of 50 mM sodium chloride to different degrees depending on age and intestinal site. At both intestinal sites, uptake capacity increased with age while there was a reduction in uptake efficiency with age. 3. At a concentration of 25 mM, both sodium chloride and potasium chloride increased uptake by ileal brush-border membrane vesicles (BBMV) of 7-d-old chicks but uptake was reduced when potassium chloride was included at a concentration of 50 mM. In the presence of valinomycin, uptake by jejunal BBMV was stimulated by 25 mM sodium chloride. In the presence of both sodium chloride and potassium chloride and in the absence of valinomycin, uptake was increased by 42.6% but this was reduced to 23.4% when the ionophore was included in the buffer. 4. The Na+-independent uptake of L-tryptophan into jejunal vesicles of 21-d-old chicks was lower in the presence of D-tryptophan than in the presence of 2-aminobicyclo-[2,2,1]-heptane-2-carboxylic acid (BCH). The inclusion of BCH in the incubation medium at low concentrations significantly enhanced the uptake of 0.04 mM L-tryptophan by jejunal BBMV. 5. At similar concentration (0.04 mM) to L-tryptophan, lysine, methionine and alanine in the presence of Na+ also stimulated L-tryptophan uptake. The uptake of L-tryptophan was reduced at a higher concentration, 25 mM, of these amino acids. 6. The study revealed a decline in rate of amino acid uptake and an increase in total uptake capacity with age. Tryptophan uptake was both Na+-independent and dependent, and occurred more in the ileum than in the jejunum. The uptake of L-tryptophan depended on the concentration of other amino acids and other factors in the diet and digesta.  相似文献   
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The methane-mitigating potency of cashew nutshell liquid (CNSL) was evaluated by investigating gas production from batch cultures using feces from Thai native ruminants that had been incubated for different periods. Feces was obtained from four Thai native cattle and four swamp buffaloes reared under practical feeding conditions at the Kasetsart University farm, Thailand. Fecal slurry from the same farm was also included in the analysis. CNSL addition successfully suppressed the methane production potential of feces from both ruminants by shifting short chain fatty acid profiles towards propionate production. Methane mitigation continued for almost 150 days, although the degree of mitigation was more apparent from Day 0 to Day 30. Bacterial and archaeal community shifts with CNSL addition were observed in feces from both ruminants; specifically, Bacteroides increased, whereas Lachnospiraceae and Ruminococcaceae decreased in feces to which CNSL was added. Fecal slurry did not show marked changes in gas production with CNSL addition. The findings showed that the addition of CNSL to the feces of ruminants native to the Southeast Asian region can suppress methane emission. Because CNSL can be easily obtained as a byproduct of the local cashew industry in this region, its on-site application might be ideal.  相似文献   
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In marine ecosystems, phage predation (phage-mediated cell lysis) is an important driver of bacterial mortality through host cell death and nutrient cycling through the release of cell contents. Both of these impacts increase marine microbial diversity by increasing interspecific competition. By contrast, very little is known about the role of phage predation in terrestrial ecosystems. A recent field study in Barrow, AK found phage predation to be a key factor controlling terrestrial bacterial population dynamics in Arctic soils. When phage abundance was artificially reduced using a tea extract, antiphage treatment, bacterial abundance, and respiration increased accordingly, suggesting top-down control by phages. The goal of this study was to examine the impact of phage predation in temperate soil ecosystems. Laboratory-scale experiments confirmed the potent antiphage properties of tea extracts. However, field experiments conducted at two discrete sites (upland and wetland) yielded little evidence that top-down control by phage predation was significant in temperate soils.  相似文献   
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We have provided a detailed structural analysis of porcine alveolar macrophage TLR3 extracellular domain (ECD). The porcine TLR3-ECD contains 18 leucine-rich repeats (LRRs) consisting of blocks of consensus motifs and non-consensus motifs containing insertions. Excluding the N-terminal and C-terminal LRRs, porcine TLR3 has two LRRs with insertions, resulting in one LRR of 39 amino acids and another LRR of 34 amino acids. Furthermore, we have conducted the first examination of the regulated expression of porcine alveolar macrophage TLR3 during in vivo co-infection with influenza virus and Bordetella bronchiseptica. There was a bi-phasic upregulation of porcine TLR3 during influenza virus infection (day 1 and day 10 post-infection). Co-infection resulted in an enhanced expression of porcine TLR3 only at day 1 post-infection. Interestingly, B. bronchiseptica induced an upregulation in alveolar macrophage TLR3 expression at day 10 post-infection. Based on our work and that of others, TLR3 likely plays a key role in the immune response of lung cells to influenza virus infection in several mammalian species.  相似文献   
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