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1.
H Härtel S Nikunen E Neuvonen R Tanskanen S-L Kivelä P Aho T Soveri H Saloniemi 《Acta veterinaria Scandinavica》2004,45(4):193-200
Pathogens causing bovine respiratory tract disease in Finland were investigated. Eighteen cattle herds with bovine respiratory
disease were included. Five diseased calves from each farm were chosen for closer examination and tracheobronchial lavage.
Blood samples were taken from the calves at the time of the investigation and from 86 calves 3–4 weeks later. In addition,
6–10 blood samples from animals of different ages were collected from each herd, resulting in 169 samples. Serum samples were
tested for antibodies to bovine parainfluenza virus-3 (PIV-3), bovine respiratory syncytial virus (BRSV), bovine coronavirus
(BCV), bovine adenovirus-3 (BAV-3) and bovine adenovirus-7 (BAV-7). About one third of the samples were also tested for antibodies
to bovine virus diarrhoea virus (BVDV) with negative results. Bacteria were cultured from lavage fluid and in vitro susceptibility
to selected antimicrobials was tested. According to serological findings, PIV-3, BAV-7, BAV-3, BCV and BRSV are common pathogens
in Finnish cattle with respiratory problems. A titre rise especially for BAV-7 and BAV-3, the dual growth of Mycoplasma dispar and Pasteurella multocida, were typical findings in diseased calves. Pasteurella sp. strains showed no resistance to tested antimicrobials. Mycoplasma bovis and Mannheimia haemolytica were not found. 相似文献
2.
Oximes, nitriles and 2-hydroxynitriles as precursors in the biosynthesis of cyanogenic glucosides 下载免费PDF全文
The biosynthesis of the cyanogenic glucosides, linamarin and prunasin, was investigated in linen-flax, peach and cherry-laurel shoots. It was shown that related 2-oximino acids, aldoximes, nitriles and 2-hydroxynitriles were generally good precursors of the aglycone moiety. Studies with double-labelled compounds confirmed the retention of the oximino nitrogen atom from 2-oximinoisovaleric acid and isobutyraldoxime in the biosynthesis of linamarin. A general pathway from amino acids to cyanogenic glucosides involving N-hydroxyamino acids, aldoximes, nitriles and 2-hydroxynitriles is proposed. 相似文献
3.
Discontinuous DNA replication: accumulation of Simian virus 40 DNA at specific stages in its replication. 总被引:17,自引:0,他引:17
The number of proline residues in a protein should have very marked consequences for the rates of protein unfolding and refolding according to the model proposed by Brandts et al. (1975). Kinetic simulations of this model indicate that the half-time for refolding of a polypeptide chain with 20 proline residues should be greater than 10 minutes and should increase by about an order of magnitude for each additional 10 proline residues. Various means are considered by which the rate of protein folding in vivo and in vitro might be increased. 相似文献
4.
Gabriella Galatà Andrés C. García-Montero Thomas Kristensen Ahmed A.Z. Dawoud Javier I. Muñoz-González Manja Meggendorfer Paola Guglielmelli Yvette Hoade Ivan Alvarez-Twose Christian Gieger Konstantin Strauch Luigi Ferrucci Toshiko Tanaka Stefania Bandinelli Theresia M. Schnurr Torsten Haferlach Sigurd Broesby-Olsen Hanne Vestergaard William J. Tapper 《American journal of human genetics》2021,108(2):284-294
5.
Heidi Maria Nistelberger SarahLouise Tapper David J. Coates Shelley L. McArthur Margaret Byrne 《Ecology and evolution》2021,11(2):1069
The impact of Quaternary glaciation on the development of phylogeographic structure in plant species is well documented. In unglaciated landscapes, phylogeographic patterns tend to reflect processes relating to persistence and stochasticity, yet other factors, associated with the palaeogeographical history of the landscape, including geomorphological events, can also have a significant influence. The unglaciated landscape of south‐western Western Australia is an ideal location to observe these ancient drivers of lineage diversification, with tectonic activity associated with the Darling Fault in the late Pliocene attributed to patterns of deep phylogeographic divergence in a widespread tree from this region. Interestingly, other species within this region have not shown this pattern and this palaeogeographical boundary therefore presents an opportunity to examine age and historical distribution of plant species endemic to this region. In this study, we assess patterns of genetic diversity and structure across 28 populations of the widespread shrub Banksia sessilis using three cpDNA markers and nine nuclear microsatellite markers. Sixteen cpDNA haplotypes were identified, comprising two major chloroplast DNA lineages that are estimated to have diverged in the Pliocene, approximately 3.3 million years ago. This timing coincides with major geomorphological processes in the landscape, including the separation of the Darling Plateau from the adjacent Swan Coastal Plain, as well as eustatic changes on the Swan Coastal Plain that are likely to have resulted in the physical isolation of historical plant lineages. Chloroplast lineages were broadly aligned with populations associated with older lateritic soils of the Darling Plateau and Geraldton sandplains or the younger sandy soils associated with the Swan Coastal Plain and Southern Coastline. This structural pattern of lateritic versus non‐lateritic division was not observed in the nuclear microsatellite data that identified three genetic clades that roughly corresponded to populations in the North, South, and Central portions of the distributions. 相似文献
6.
α1-Microglobulin is a 26 kDa plasma and tissue glycoprotein that belongs to the lipocalin protein superfamily. Recent reports show that it is a reductase and radical scavenger and that it binds heme and has heme-degrading properties. This study has investigated the protective effects of α1-microglobulin against oxidation by heme and reactive oxygen species in the human erythroid cell line, K562. The results show that α1-microglobulin prevents intracellular oxidation and up-regulation of heme oxygenase-1 induced by heme, hydrogen peroxide and Fenton reaction-generated hydroxyl radicals in the culture medium. It also reduces the cytosol of non-oxidized cells. Endogeneous expression of α1-microglobulin was up-regulated by these oxidants and silencing of the α1-microglobulin expression increased the cytosol oxidation. α1-microglobulin also inhibited cell death caused by heme and cleared cells from bound heme. Binding of heme to α1-microglobulin increased the radical reductase activity of the protein as compared to the apo-protein. Finally, α1-microglobulin was localized mainly at the cell surface both when administered exogeneously and in non-treated cells. The results suggest that α1-microglobulin is involved in the defence against oxidative cellular injury caused by haemoglobin and heme and that the protein may employ both heme-scavenging and one-electron reduction of radicals to achieve this. 相似文献
7.
8.
C-W Fan T Chen Y-N Shang Y-Z Gu S-L Zhang R Lu S-R OuYang X Zhou Y Li W-T Meng J-K Hu Y Lu X-F Sun H Bu Z-G Zhou X-M Mo 《Cell death & disease》2013,4(10):e828
Accumulating evidence indicates that cancer-initiating cells (CICs) are responsible for cancer initiation, relapse, and metastasis. Colorectal carcinoma (CRC) is typically classified into proximal colon, distal colon, and rectal cancer. The gradual changes in CRC molecular features within the bowel may have considerable implications in colon and rectal CICs. Unfortunately, limited information is available on CICs derived from rectal cancer, although colon CICs have been described. Here we identified rectal CICs (R-CICs) that possess differentiation potential in tumors derived from patients with rectal adenocarcinoma. The R-CICs carried both CD44 and CD54 surface markers, while R-CICs and their immediate progenies carried potential epithelial–mesenchymal transition characteristics. These R-CICs generated tumors similar to their tumor of origin when injected into immunodeficient mice, differentiated into rectal epithelial cells in vitro, and were capable of self-renewal both in vitro and in vivo. More importantly, subpopulations of R-CICs resisted both 5-fluorouracil/calcium folinate/oxaliplatin (FolFox) and cetuximab treatment, which are the most common therapeutic regimens used for patients with advanced or metastatic rectal cancer. Thus, the identification, expansion, and properties of R-CICs provide an ideal cellular model to further investigate tumor progression and determine therapeutic resistance in these patients. 相似文献
9.
Tapper JE Ronsky JL Powers MJ Sutherland C Majima T Frank CB Shrive NG 《Journal of biomechanical engineering》2004,126(2):301-305
The ovine stifle joint is a promising animal model for investigation of joint mechanobiology. A method for in vivo measurement of dynamic 3-D kinematics of the ovine stifle joint is described (accuracy: 0.36 +/- 0.39 mm). Inter-subject variability in kinematics is greater than both intra-subject and inter-session variability. For future studies in which joint kinematics are measured prior to and following controlled orthopaedic interventions, pooling of data should be avoided and each subject should act as its own control. 相似文献
10.