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991.
Genome rearrangements of bovine rotavirus after serial passage at high multiplicity of infection 总被引:10,自引:0,他引:10
After serial passage at high multiplicity of infection of standard bovine rotavirus in MA104 cells, different genome rearrangements occurred in which segment 5 was lost from the RNA profile and distinct additional bands of double-stranded (ds) RNA were found in positions on gels between segments 1 and 6. It was shown that some of the additional RNA bands contained segment 5-specific sequences. The additional RNA bands were transcribed in vitro to apparent full length. Analysis of the proteins synthesized in cells infected with viruses possessing rearranged genomes showed that in all cases the product of RNA segment 5, VP5, was missing; however, in one case an abnormal protein was observed which corresponded in size to the coding capacity of the mRNA transcribed from the additional genomic RNA band. Viruses with rearranged genomes could be plaque purified, and they grew in the absence of standard virus to titers comparable to those obtained from standard virus. In mixed infections of standard virus and virus possessing genome rearrangements, standard virus overgrew during passage at low multiplicity of infection whereas virus possessing genome rearrangements overgrew during passage at high multiplicity of infection. 相似文献
992.
993.
Comparison of the immediate effects of five beta-adrenoreceptor-blocking drugs with different ancillary properties in angina pectoris 总被引:4,自引:0,他引:4
U Thadani C Davidson W Singleton S H Taylor 《The New England journal of medicine》1979,300(14):750-755
We compared the immediate effects of five beta-adrenoreceptor-blocking agents in 16 patients with stable angina pectoris. Acute dose-response studies showed that all five drugs improved exercise tolerance and reduced ST-segment depression, heart rate and blood pressure by a similar degree in comparison with a placebo (P less than 0.01). Near maximum improvement in exercise tolerance occurred when the acute cumulative oral dose had reached 160 mg for propranolol and oxprenolol, 200 mg for metoprolol and tolamolol and 400 mg for practolol. When these drugs were administered as a single doses, increase in walking time before the development of angina and reduction in ST-segment depression, heart rate and systolic blood pressure all occurred within one hour and persisted for eight hours--effects markedly different from the response to a placebo (P less than 0.01). These data show that non-cardioselective agents (propranolol and oxprenolol), cardioselective agents (practolol, metoprolol and tolamolol), as well as drugs with intrinsic sympathomimetic activity (oxprenolol and practolol), were equally effective in the treatment of angina pectoris. 相似文献
994.
995.
The atopy patch test -- reproducibility and comparison of different evaluation methods 总被引:2,自引:0,他引:2
Heinemann C Schliemann-Willers S Kelterer D Metzner U Kluge K Wigger-Alberti W Elsner P 《Allergy》2002,57(7):641-645
BACKGROUND: There is still a lack of standardization of the atopy patch test (APT) in test procedures and evaluation methods. Our aim was to examine the reproducibility of APT results and to compare visual evaluation to chromametry and laser Doppler imaging. METHODS: Fifty-two volunteers with atopic eczema/dermatitis syndrome (AEDS) were included. The APT was performed on tape-stripped and unstripped test fields on their backs using cat dander, house dust mite and grass pollen allergens from two different suppliers. Responders were re-tested 4-12 weeks later with the same allergens on their forearms. RESULTS: Using Allergopharma allergens, 14 (26.9%) volunteers showed one or more positive reactions. The reproducibility rate was 56.3%. The Erlangen atopy score in APT-positive and negative volunteers was 19 +/- 6 vs 15 +/- 6. The test agreement in volunteers tested with both allergens, from Allergopharma and Stallergènes, was poor. Correlation of the results between the three evaluation methods was significant (P < or = 0.001). CONCLUSIONS: The low reproducibility rate of APT results and the poor inter-test-agreement using allergens from different suppliers show that much work remains to make the APT a reliable tool in identifying relevant aeroallergens that lead to flare ups of AEDS. Compared to chromametry and laser Doppler imaging, visual scoring was superior in differentiation between irritative and allergic reactions. 相似文献
996.
997.
U Moebius G Kober A L Griscelli T Hercend S C Meuer 《European journal of immunology》1991,21(8):1793-1800
Human CD8+ lymphocyte subpopulations were analyzed for their expression of CD8 alpha and CD8 beta subunits. Investigations with uncloned peripheral blood lymphocytes as well as cloned human natural killer and T cell subpopulations demonstrate that CD3- natural killer cells, T cell receptor gamma/delta, and CD4+CD8+ T cell clones express exclusively CD8 alpha gene products. Structural analysis of CD8 molecules demonstrates that CD8 alpha+/beta- T lymphocytes surface express 75-kDa CD8 alpha/alpha homodimers whereas CD8 alpha/beta lymphocytes express concomittantly two CD8 isoforms of different molecular masses (67 kDa and 75 kDa, respectively). Peptide mapping of these latter two isoforms suggests that CD8 is expressed as alpha/alpha homodimers and alpha/beta heterodimers on CD8 alpha/beta+ cells. Importantly, we found that the two CD8 isoforms behave functionally different. Thus, in contrast to CD8 alpha/beta+/CD8 alpha/alpha+ T lymphocytes, cytolytic activity of CD8 alpha/beta-/CD8 alpha/alpha+ T cell clones was not inhibited by anti-CD8 monoclonal antibodies and the latter were not induced to proliferate following CD3/CD8 cross-linking. 相似文献
998.
999.
D. Kirsten U. Rieger K. H. Schröder A. Böhle H. Magnussen 《Journal of molecular medicine (Berlin, Germany)》1993,71(10):787-790
Summary Immunotherapy using bacille Calmette-Guérin (BCG) has gained increasing acceptance in the management of superficial bladder cancer. Systemic reactions after intravesical instillation of BCG are rare. However, when the therapy is complicated, the lung often becomes involved. Since the pathogenesis of lung infiltrates after immunotherapy is unknown, we report on a patient who developed a lung infiltrate after receiving BCG immunotherapy for bladder cancer. The infectious etiology was established by culture confirmation of a BCG strain in the broncheoalveolar lavage fluid.Abbreviation BCG
bacille Calmette-Guérin 相似文献
1000.