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311.
Springer S Lindner T Ahrens M Woitow G Prandini F Selbitz HJ 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(3-4):89-93
The aim of this study was to examine the duration of immunity of different vaccination schemes using the S. enteritidis live vaccine Gallivac Se and the S. enteritidis-S. typhimurium inactivated vaccine Gallimune Se+St. Three groups of Lohman Brown chickens were used. Group one was vaccinated three times orally with Gallivac Se at weeks one, seven and 13 of age. Group two was vaccinated twice orally with Gallivac Se in weeks one and seven and once i.m. with Gallimune Se+St in week 14 of age. A third group was not vaccinated and served as the control group. Eight randomly selected chickens from each of the three groups were challenged with a nalidixic acid resistant S. enteritidis PT4 strain in weeks 24, 51 and 71 of age and the same number of animals were challenged with a S. typhimurium DT 104 strain in weeks 26, 54 and 73 (75) of age.The chickens were euthanised seven days post challenge and the number of challenge strain organisms (log10 cfu) in the liver and on caecal mucosa was determined.The quantitative investigation of the challenge strain in the liver and caecal mucosa revealed a statistically significant (p < 0.05) lower challenge strain burden in the vaccinated groups compared with the non-vaccinated control group up to week 71 (73) of age. The protective effects were demonstrated for both challenge strains. 相似文献
312.
Klier J May A Fuchs S Schillinger U Plank C Winter G Gehlen H Coester C 《Veterinary immunology and immunopathology》2011,144(1-2):79-87
Recurrent airway obstruction (RAO) in horses has become a common problem in stabled horses in industrialized countries and deserves new therapeutic strategies. CpG-oligodeoxynucleotides (CpG-ODNs) were developed as effective immunostimulating agents to induce a Th2/Th1 shift. These agents showed a beneficial therapeutic effect in allergic diseases with predominant Th2 immunoresponse. CpG-ODN delivery by gelatin nanoparticles (GNPs) resulted in enhanced cellular uptake in murine and human in vitro studies and was a starting point for the present trial. The aim of this study was to identify an optimal stimulating CpG motif in horses with regard to species specificity on equine bronchoalveolar lavage (BAL) cells, in terms of a possible specific immunomodulation effect (Th2/Th1 shift) by used CpG-ODN. Accordingly, GNPs were evaluated as a delivery system to improve CpG-ODN immunostimulation in equine BAL cells. BAL fluid (BALF) was obtained from seven horses with moderate RAO and from four healthy horses and was subsequently incubated with five different CpG-ODN sequences (from A-, B- and C-class) and one ODN without any CpG motif. Release of three key cytokines (IL-4, IL-10 and IFN-γ) was quantified by ELISA to detect an allergy mediated Th2 immunoresponse (IL-4) as well as a proinflammatory Th1 response (IFN-γ). Due to its specific anti-inflammatory and anti-allergic effects, IL-10 was considered as a beneficial agent in pathophysiology of RAO. Results showed a significant upregulation of IL-10 and IFN-γ on the one hand and a downregulation of IL-4 on the other hand in RAO affected horses. Cell cultures from healthy horses had a significantly stronger response in cytokine release to all the applied stimuli in contrast to RAO derived cells. Comparing all five CpG sequences, A-class 2216 significantly showed the highest immunomodulatory effects on equine BALF cells and, hence, was chosen for follow-up preliminary clinical studies. 相似文献
313.
314.
Axel Panse Franz-Xaver Maidl Johann Dennert Rüdiger Müller Gerhard Fischbeck 《植物养料与土壤学杂志》1995,158(3):221-229
Effect of combined slurry and mineral fertilization on yield formation, yield components and nitrogen efficiency of winter wheat From 1984/85 to 1987/88 field trials were conducted on the experimental farm Roggenstein in order to examine the efficiency of pig slurry applied at different developmental stages of winter wheat combined with different dosage and distributions of mineral N-fertilizer. On the average over 4 years, maximum grain yield by applying exclusively mineral N-fertilizer has been achieved with 120 kg N/ha, with the optimal amount of N-fertilizer at the 3 developmental stages being 40 kg N/ha, respectively. Decreased yields induced by a reduced mineral N-fertilization could be compensated by application of 20 m3/ha or 40 m3/ha slurry either at the beginning of the growing period, EC 30-31 or EC 33-35 developmental stages. However, mineral fertilizer equivalents calculated on the basis of the NH4? N-content of slurries for each year ranged from 25 to 79 in dependence of application date and prevailing weather conditions. Regarding the effect on yield components, no difference between slurry and mineral N-fertilizer were observed. The mediocre and very variable efficiency of slurry-N leads to the conclusion, that the use of slurry in cereal production may be of limited value for agronomic as well as for ecological reasons, as long as no efficient and cost-effective application techniques are available. 相似文献
315.
Seven Quaternary profiles from the Mediterranean region of northern Tunisia are described and their geomorphological significance assessed. Fifteen radiocarbon datings permit the field observations to be arranged in a chronosequence.The results indicate that the Late Pleistocene period witnessed the production and displacement of coarse debris, a process extending down to low altitudes. Until now, however, the only evidence for this has been found in the vicinity of steep slopes or rock walls. The coarse sediments partly overlie slope deposits derived from reddish soils; to some extent they contain fine reddish pedogenic material, and in part they are covered by it.In the Holocene, the displacement of fine alluvial sediments alternated several times with the formation of humic horizons. Anthropogenic influences on landscape evolution must be admitted as a possibility as from at least three thousand years ago.The aeolian sands of the Late Pleistocene and Middle Holocene are correlated with regressions of high sea levels. 相似文献
316.
Rached PA Canola JC Schlüter C Laus JL Oechtering G de Almeida DE Ludewig E 《Veterinary ophthalmology》2011,14(3):174-179
The aims of the study were (1) to quantify the influence of selected imaging parameters on the image quality (slice thickness, mAs, and beam orientation) defining optimal conditions for scan protocols and (2) to evaluate the benefits of the 3D reconstruction techniques for visualization of NDS structures in dogs. CT-DCG was performed bilaterally in 32 heads of dogs. CT transverse images were obtained using a combination of two slice thickness values (0.8 mm and 2 mm) and two mAs values (50 mAs and 300 mAs). Two beam projection orientations were also tested: transverse plane (perpendicular to the hard palate) and oblique to the hard palate. Three-dimensional images were obtained using Volume Rendering (VR). Transverse beam projection proved to be superior for the assessment of the inferior and superior lacrimal canaliculi and lacrimal sac. In this study, there was no statistical difference regarding mAs values (50 mAs and 300 mAs) and slice thickness values (0.8 mm and 2 mm). Three-dimensional images were helpful for the assessment of topographic relationship between nasolacrimal structures and cranial landmarks. 相似文献
317.
Bienko M Green CM Crosetto N Rudolf F Zapart G Coull B Kannouche P Wider G Peter M Lehmann AR Hofmann K Dikic I 《Science (New York, N.Y.)》2005,310(5755):1821-1824
Translesion synthesis (TLS) is the major pathway by which mammalian cells replicate across DNA lesions. Upon DNA damage, ubiquitination of proliferating cell nuclear antigen (PCNA) induces bypass of the lesion by directing the replication machinery into the TLS pathway. Yet, how this modification is recognized and interpreted in the cell remains unclear. Here we describe the identification of two ubiquitin (Ub)-binding domains (UBM and UBZ), which are evolutionarily conserved in all Y-family TLS polymerases (pols). These domains are required for binding of poleta and poliota to ubiquitin, their accumulation in replication factories, and their interaction with monoubiquitinated PCNA. Moreover, the UBZ domain of poleta is essential to efficiently restore a normal response to ultraviolet irradiation in xeroderma pigmentosum variant (XP-V) fibroblasts. Our results indicate that Ub-binding domains of Y-family polymerases play crucial regulatory roles in TLS. 相似文献
318.
Cirak F Cisternas JE Cuitiño AM Ertl G Holmes P Kevrekidis IG Ortiz M Rotermund HH Schunack M Wolff J 《Science (New York, N.Y.)》2003,300(5627):1932-1936
Because of the small thermal capacity of ultrathin ( approximately 200 nanometers) metal single crystals, it is possible to explore the coupling of catalytic and thermal action at low pressures. We analyzed a chemothermomechanical instability in this regime, in which catalytic reaction kinetics interact with heat transfer and mechanical buckling to create oscillations. These interacting components are separated and explored through experimentation, mathematical modeling, and scientific computation, and an explanation of the phenomenon emerges from their synthesis. 相似文献
319.
Imbschweiler I Kummerfeld M Gerhard M Pfeiffer I Wohlsein P 《Veterinary journal (London, England : 1997)》2009,182(3):481-483
A case of animal sexual abuse and sadism in a female sheep is described. The animal suffered severe genital tract injury most likely caused by the insertion and manipulation of a branch of wood and by penile penetration by a human male. Postmortem examination revealed multiple perforations of the vagina with massive haemorrhages. Animal sexual abuse is a complex diagnostic problem in veterinary medicine. Reported cases are often linked to sadism and often lead to the animal's death. Veterinarians should keep in mind animal sexual abuse as a differential diagnosis in cases of anogenital injuries of unknown origin. 相似文献
320.
François Serres Jean-Louis Pouchelon Laure Poujol Hervé P. Lefebvre Cathy Trumel Thomas Daste Carolina Carlos Sampedrano Vassiliki Gouni Renaud Tissier Gerhard Hawa Valérie Chetboul 《Journal of Veterinary Cardiology》2009,11(2):103-121