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991.
In vitro and in vivo comparisons of valnemulin, tiamulin, tylosin, enrofloxacin, and lincomycin/spectinomycin against Mycoplasma gallisepticum 总被引:1,自引:0,他引:1
The minimum inhibitory concentrations (MICs) for valnemulin, tiamulin, enrofloxacin, tylosin, and lincomycin/spectinomycin were determined for a virulent strain of Mycoplasma gallispeticum (MG). At the initial reading, the lowest MICs were seen with valnemulin and tiamulin, followed by tylosin, enrofloxacin, and a relatively high MIC for lincomycin/spectinomycin. At the final reading, at 14 days, a similar pattern was obtained, with valnemulin giving the lowest MIC (< 0.008 mg/ml). The same strain of MG was used to infect groups of 20 2-day-old chicks in two separate experiments. In both, several concentrations of valnemulin and tiamulin and one each of tylosin and enrofloxacin were administered to separate groups in the drinking water. In the second experiment, one group of chicks was given lincomycin/spectinomycin. Each experiment had one infected unmedicated group and an uninfected unmedicated group. Mortality, clinical signs, and gross lesions, in both experiments, were significantly less (P < 0.001) in the uninfected and infected medicated groups (except for the two lowest dosages of valnemulin, lincomycin, and spectinomycin) than in the infected unmedicated groups. Also, the mean body weight gain was greater in the uninfected and infected medicated groups. Among the infected birds, MG was recovered from fewer chicks in the infected medicated groups except for the lowest two dosages of valnemulin. Serologic results were negative for the uninfected groups, and there were fewer positive reactors for the infected medicated groups except for the group treated with lincomycin/spectinomycin. Valnemulin should prove to be a useful addition to the antimicrobials in the control of MG infection in chickens. 相似文献
992.
993.
We report the case of a 17-yr-old man diagnosed as a toluene abuser. He had an 8-mo history of toluene inhalation exposure and was admitted to this hospital with symptoms of auditory and visual hallucination. Magnetic resonance imaging (MRI) revealed no structural abnormalities both on T1- and T2-weighted images, whereas SPECT using 99mTc-ethyl cysteinate dimer (ECD) showed multifocally decreased perfusion in the cerebral cortex, basal ganglia and thalami. Our case indicates that SPECT detects early central nervous system injury from toluene inhalation even when neurological examination and neuroanatomic imaging such as MRI are normal. 相似文献
994.
J Schwab M Schwab K Manger B Manger PH Wünsch M Gottwik 《Canadian Metallurgical Quarterly》1998,123(16):487-492
HISTORY AND CLINICAL FINDINGS: A 47-year-old woman was admitted because of diarrhoea (3-5 stools daily) for 9 days, weakness for 3 weeks and painful wrist swelling, arthralgia and hyperesthesia over the medial aspect of the right thigh for 6 weeks. For 6 years she had been treated for asthma. Two operation had been performed for chronic sinusitis. ADMISSION FINDINGS AND INVESTIGATIONS: There was marked eosinophilia (5889/microliter) and thrombocytopenia (96,000/microliter), markedly increased serological inflammatory parameters and a raised total IgE level (134 IU/ml). The chest radiogram showed pulmonary infiltrates and bone marrow biopsy indicated eosinophilia. Echocardiography revealed a mass, 3 x 8 cm, in the ventral wall of the right ventricle with extension into the outflow tract. DIAGNOSIS, TREATMENT AND COURSE: These findings met the criteria of the American College of Rheumatology for Churg-Strauss syndrome (CSS). On methylprednisolone (1 mg/kg daily) the eosinophil and platelet counts became normal within 5 days and erythrocyte sedimentation rate and the level of C-reactive protein fell. Under cardiopulmonary bypass the tumour was removed, the tricuspid valve replaced, and the right ventricle reconstructed. Histology of the mass revealed it to be an organized thrombus. CONCLUSION: The relationship between the thrombus formation and CSS is unclear. Hypercoagulability connected with the inflammatory process may have played a part in the pathogenesis. 相似文献
995.
PH Berger SD Wyatt PJ Shiel MJ Silbernagel K Druffel GI Mink 《Canadian Metallurgical Quarterly》1997,142(10):1979-1999
The 3'-terminal nucleotide sequences of thirteen authenticated strains of bean common mosaic virus (BCMV) and one strain of bean common mosaic necrosis virus (BCMNV) were obtained. The regions sequenced included the coat protein coding sequence and 3'-end non-coding region. These data, combined with sequence information from other legume-infecting potyviruses and the Potyviridae were used for phylogenetic analysis. Evidence is provided for delineation of BCMNV as distinct from BCMV and the inclusion of azuki mosaic, dendrobium mosaic, blackeye cowpea mosaic, and peanut stripe viruses as strains of BCMV. This relationship defines the members of the BCMV and BCMNV subgroups. These data also provide a basis upon which to define virus strains, in combination with biological data. Other aspects and implications of legume-infecting potyvirus phylogenetics are discussed. 相似文献
996.
PH Kitzman TN Perrone AM LeMaster BM Davis KM Albers 《Canadian Metallurgical Quarterly》1998,35(3):258-270
Neurotrophins play an essential role in sensory development by providing trophic support to neurons that innervate peripheral targets. Nerve growth factor (NGF), neurotrophin-3, neurotrophin-4, and brain-derived neurotrophin exert their survival effect by binding to two transmembrane receptor types: trk receptors, which exhibit binding specificity, and the p75NTR receptor, which binds all neurotrophins. To determine how target-derived neurotrophins affect sensory neuron development and function, we used transgenic mice that overexpress NGF in the skin to examine the impact of NGF overexpression on receptor expression. Previous studies of trk expression in trigeminal ganglia of adult NGF transgenics showed that the percentage of trkA neurons doubled and their number increased fivefold. The present study focused on the p75 receptor and shows that the percentage of neurons expressing p75NTR also increase in NGF ganglia, but only by 10%. This increase did not encompass the small, BS-IB-4 isolectin-positive cells as they remained p75 negative in transgenic ganglia. Interestingly, levels of trkA protein were not increased on a per-cell level, whereas levels of p75NTR increased nearly threefold. These results show that in sensory systems, target-derived NGF modulates the level of p75NTR receptor expression, and in so doing, may act to regulate the formation of functional receptor complexes and subsequent trophic action. 相似文献
997.
Patients with acute renal failure in the intensive care unit have high in-hospital mortality. In this setting, decision making with regard to the initiation or discontinuation of dialysis by physicians, patients, and families is challenging because of the desire of all for the patient to recover while sparing unnecessary suffering. Decision making can be facilitated by knowledge of outcomes of the treatment of such patients in the medical literature. This knowledge assists nephrologists to distinguish those patients whose clinical situation indicates a more favorable prognosis from those whose prognosis is uncertain or definitely poor even with dialysis. This information, combined with consideration of relevant ethical guidelines, provides a framework for nephrologists to make decisions that are evidence based and ethically sound. We present and discuss two cases to show the application of evidence-based medicine and ethical considerations to decision making for patients with acute renal failure in the intensive care unit. 相似文献
998.
PH Olesen P Sauerberg TG Petersen S Treppendahl B Bentzen J Deeter JS Ward CH Mitch SV Lehmann 《Canadian Metallurgical Quarterly》1997,9(8):739-749
Methods for the synthesis of each of the four stereoisomers of 6-(3-propylthio-1,2,5-thiadiazol-4-yl)-1-azabicyclo[3.2.1]oc tane (10, 11, 12, and 13) and 3-(3-propylthio-1,2,5-thiadiazol-4-yl)-1-azabicyclo[2.2.1]he ptane (18, 19, 20, and 21), and the two stereoisomers of 3-(3-propylthio-1,2,5-thiadiazol-4-yl)-1-azabicyclo[2.2.2]oc tane (27 and 28) were developed. The relative configuration of the compounds was determined on the basis of previously described 1H NOE experiments, and the absolute configuration of 6-(3-propylthio-1,2,5-thiadiazol-4-yl)-1-azabicyclo[3.2.1]oc tanes (10, 11, 12, and 13) and 3-(3-propylthio-1,2,5-thiadiazol-4-yl)-1-azabicyclo[2.2.2]oc tane (27 and 28) was determined by single crystal X-ray crystallography. Optical purity was determined by capillary electrophoresis (CE) using chiral selectors as trimethyl-beta-cyclodextrin and heparin dissolved in the running buffer. All the 3-(3-propylthio-1,2,5-thiadiazol-4-yl)-1-azabicycles had low nanomolar affinity for muscarinic receptors as determined by displacement of radiolabelled oxotremorine-M (3H-Oxo-M) and pirenzepine (3H-Pz) from cortical rat brain homogenates. The binding assay discriminated between diastereomers, but only a minor degree of enantioselectivity was observed in the binding assays. 相似文献
999.
1000.