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731.
The authors studied the antigenic composition of 105 Sh. sonnei strains freshly isolated from patients suffering from acute dysentery and carriers. Immunophoregrams of pure S-and R-forms species were obtained. Up to 13 antigens differing by electrophoretic and diffusion mobility and immunological specificity were revealed among soluble Sh. sonnei antigens The position of common and specific antigens was determined on the immunophoregram. Along with the thermostable somatic O-antigen detected at the I phase of the S-forms, and two thermolabile O-antigen components at the II phase, and the R-forms, there was revealed a surface, relatively thermolabile, K-antigen of A-type capable of agglutinating live bacteria in the O-antiserum; position of the latter on the immunophoregram was also determined. 相似文献
732.
Jane Rhein Voos 《American journal of botany》1969,56(8):898-909
An investigation of the life cycle of Caulochytrium gloeosporii Voos and Olive, a parasite of Gloeosporium, has confirmed the existence of an alternation of generations. Zoospores from sessile sporangia may develop vegetatively into similar sporangia or they may function as isogametes, fusing in pairs to produce cysts (zygotes) that give rise to slender-stalked aerial sporangia. Meiosis is believed to occur in the aerial sporangium, which at germination liberates eight asexual zoospores. The species is homothallic. 相似文献
733.
Shungang Wan Guiying Li Taicheng An Bin Guo Lei Sun Lei Zu Ailing Ren 《Biodegradation》2010,21(6):1057-1066
In the present study, a new bacterial strain isolated from activated sludge has been identified as Lysinibacillus sphaericus based on its morphology, physiochemical properties, and the results of 16S ribosomal RNA (rRNA) gene sequence analysis. This
new bacterial strain uses ethanethiol as both carbon source and energy source. The key factors for controlling the degradation
efficiency of ethanethiol by this strain were found to be initial ethanethiol concentration, temperature, and pH value of
solutions. Under the optimized conditions, as well as 4 mg l−1 ethanethiol, 30°C, and pH = 7.0, almost 100% ethanethiol can be degraded within 96 h and sulfate as a final product was detected
in aqueous medium. The degradation reaction of ethanethiol over this newly isolated strain can be described by pseudo first-order
equation in which the maximum degradation rate constant K and the minimum half-life were respectively calculated to be 0.0308 h−1 and 22.5 h under the optimal conditions. 相似文献
734.
Specimens of brain tissue obtained at autopsy from three patients suffering from progressive multifocal leukoencephalopathy (PML) were examined by electron microscopy. In specimens from all three cases particles similar to those of the papova virus group were present, confirming previous observations. By the negative staining method it was possible to define the morphological characteristics of the particles more precisely and it was shown that they are structurally similar to virions of the polyoma-SV40-K type. The need is emphasized for obtaining fresh unfixed diseased tissue from persons suffering from PML in order that the biological properties of the particles can be investigated. 相似文献
735.