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41.
Non-methylated CpG motifs, present in viral and bacterial DNA, are one of many pathogen-associated molecular patterns (PAMP) recognized by the mammalian innate immune system. Recognition of this PAMP occurs through a specific interaction with toll-like receptor 9 (TLR9) and this interaction can induce cytokine responses that influence both innate and adaptive immune responses. Previous investigations determined that both the flanking sequences in synthetic CpG oligodeoxynucleotides (CpG ODN) and the cellular pattern of TLR9 expression can influence species-specific responses to CpG ODN. Therefore, the structure, function and cellular distribution of bovine TLR9 were compared with what is known for mice and human. Analysis of the bovine TLR9 gene revealed greater sequence homology between cattle and humans than cattle and mice Similar CpG motifs induced optimal activation of both human and bovine leukocytes and these motifs were distinct from those which activated mouse leukocytes. Functional analyses with CpG ODN stimulated bovine blood leukocytes revealed that class A CpG ODN were more potent inducers of interferon-alpha (IFN-alpha) than class B CpG ODN. Furthermore, magnetic activated cell sorting of bovine blood leukocyte subpopulations implicated dendritic cells but not monocytes in the regulation of CpG ODN-induced IFN secretion. Thus, the cellular pattern of CpG ODN-induced responses in cattle shared many similarities with human leukocytes. Collectively, these analyses revealed substantial conservation of TLR9 structure and TLR9 function in blood leukocytes of humans, cattle and other domestic species.  相似文献   
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The objective of the current study was to describe and characterize the pharmacokinetics and selected pharmacodynamic effects of morphine and its two major metabolites in horses following several doses of morphine. A total of ten horses were administered a single intravenous dose of morphine: 0.05, 0.1, 0.2, or 0.5 mg/kg, or saline control. Blood samples were collected up to 72 hr, analyzed for morphine, and metabolites by LC/MS/MS, and pharmacokinetic parameters were determined. Step count, heart rate and rhythm, gastrointestinal borborygmi, fecal output, packed cell volume, and total protein were also assessed. Morphine‐3 glucuronide (M3G) was the predominant metabolite detected, with concentrations exceeding those of morphine‐6 glucuronide (M6G) at all time points. Maximal concentrations of M3G and M6G ranged from 55.1 to 504 and 6.2 to 28.4 ng/ml, respectively, across dose groups. The initial assessment of morphine pharmacokinetics was done using noncompartmental analysis (NCA). The volume of distribution at steady‐state and systemic clearance ranged from 9.40 to 16.9 L/kg and 23.3 to 32.4 ml min?1 kg?1, respectively. Adverse effects included signs of decreased gastrointestinal motility and increased central nervous excitation. There was a correlation between increasing doses of morphine, increases in M3G concentrations, and adverse effects. Findings from this study support direct administration of purified M3G and M6G to horses to better characterize the pharmacokinetics of morphine and its metabolites and to assess pharmacodynamic activity of these metabolites.  相似文献   
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A spotlight on snow leopard conservation in China   总被引:1,自引:0,他引:1       下载免费PDF全文
China holds the greatest proportion of the snow leopard's (Panthera uncia) global range and is central to their conservation. The country is also undergoing unprecedented economic growth, which increases both the threats to the snow leopard and the opportunities for its conservation. In this paper we aim to review published literature (from 1950 to 2014) in English and Mandarin on snow leopard ecology and conservation in China in order to identify thematic and geographic research gaps and propose research priorities. We first retrieved all published items that considered snow leopards in China (n = 106). We extracted from these papers 274 reports of snow leopard presence in China. We then reviewed a subset of papers (n = 33) of this literature, which specifically focused on snow leopard ecology and conservation within China. We introduced a thematic framework that allows a structured and comprehensive assessment of findings. This framework recognizes 4 critical and interrelated topics underpinning snow leopard ecology and conservation: habitat (distribution and protected area coverage); prey (distribution and abundance, predator–prey relationships); human interactions (hunting and trade, livestock interactions and conflicts); and the underlying policy context. Significant gains in knowledge as well as research gaps and priorities are discussed with reference to our framework. The modest quantity and limited scope of published research on the snow leopard in China calls for a continued and intensified effort to inform and support national conservation policies.  相似文献   
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Exposure of livestock grazing to forage productivity variation and to market fluctuations affects the risk of investment and returns from cow-calf operations, but little work has been done to empirically compare these returns to the returns that would be demanded by financial markets from assets with similar risk and return characteristics. This study uses historical forage production data from three rangeland locations in California, and cattle and hay prices, to simulate financial statements for three hypothetical cow-calf producers in the period 1988–2007. Return on investment from year to year incorporates the variability and risk associated with dependence on natural forage production. Performance is then compared to the actual performance of a diversified portfolio of assets using the Capital Asset Pricing Model, from which the theoretical cost of capital for these hypothetical grazing enterprises is derived. Much like other agricultural enterprises, cow-calf production in California has low market risk and a low theoretical cost of capital. This theoretical cost of capital is still greater than the historical return from livestock production (excluding land appreciation) in the western United States, adding further backing to the point often made in the literature that ranchers who engage in cow-calf production are receiving benefits beyond the commercial returns from livestock production alone.  相似文献   
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OBJECTIVE: To determine the effects of femoral prosthesis stem length and head size on cement strains in a canine hip replacement system. STUDY DESIGN: An in vitro experimental model. SAMPLE POPULATION: (1) Three standard and 3 1-cm shortened femoral implants with +3 femoral heads. (2) Two standard implants with +0, +3, and +6 femoral heads. METHODS: Femoral stems were embedded in polymethylmethacrylate cement. A uniaxial proximodistal-oriented strain gauge was applied to the cement on the medial and lateral aspects of the construct 1.5 cm, 6.0 cm and 7.0 cm distal to the collar. Each construct with a +3 femoral head was mounted in a materials testing system. An axial compressive load (0-200 N) was applied to the femoral head and cement strains were recorded. Additionally, 2 standard length constructs were also tested with +0 and +6 femoral heads. The effects of stem length and neck length on cement strains were assessed with analysis of variance. RESULTS: Strains increased at all locations with increasing loads for all constructs. Shorter implants had higher strains by 152% and 171%, lateral (P =.003) and medial (P =.0025) to the stem tip. No significant strain differences were noted, at any strain gauge location, between different neck lengths (P values ranged from.20 to.67). CONCLUSIONS: Although a shorter implant stem has a potential to improve implant fit, it led to significantly higher cement strains that may increase the risk for aseptic loosening. Changes in femoral neck length did not significantly affect cement strains under the conditions tested. CLINICAL RELEVANCE: Shortening of the femoral stem currently cannot be recommended in canine total hip replacement. The existing use of variable neck lengths likely does not increase the risk of failure of the femoral stem.  相似文献   
47.
Diagnosis of mastitis for therapy decisions.   总被引:2,自引:0,他引:2  
Identifying specific groups of mastitis pathogens by their growth on selective agars can help identify the pathogens that are present in mastitic milk samples. This article addresses issues that are essential in making good use of diagnostic procedures to improve udder health on dairies.  相似文献   
48.
The diagnosis, staging, and treatment of tumors in veterinary as well as human oncology have traditionally incorporated elements of anatomic extent of neoplasia through various clinical and pathologic methods. These clinicopathological methods have been the basis for the development of the tumor, node, and metastasis and grading systems, which have translated into clinically significant advances over the last 20 to 30 years. Unfortunately, there continues to be significant limitations to this system when prognostication and therapeutic decisions need to be made specific to a patient. For example, completely resected and cleanly staged phenotypically identical grade II mast cell tumors in dogs can have opposing clinical outcomes. In addition, dogs or cats with identical stage and grade lymphoma can have significantly divergent responses to the same multi-agent chemotherapy protocol. Numerous nonanatomic neoplastic molecular prognostic factors have been recently identified and have the potential to improve on the presently available tumor, node, and metastasis- and grading-based systems. To date in human oncology, single nonanatomic factors have only occasionally translated into efficient and independent prognostic factors, which speaks to the heterogeneity of cancer. Therefore, the use of panels of factors have been encouraged that will allow for the development of a molecular prognostic index, which can then be used in concert with presently available systems. This review will summarize how to best utilize presently available tumor, node, and metastasis- and grading-based systems, and incorporate newly available molecular prognostic factors.  相似文献   
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