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821.
822.
Lanceispora phyllophila is described based on specimens of petioles from an unidentified dicotyledonous host collected at Bukid Timan, Singapore. It is illustrated with interference contrast micrographs and compared with the type speciesL. amphibia. Lanceispora phyllophila differs fromL. amphibia in having smaller ascomata and longer ascospores.  相似文献   
823.
A tranfser system was used to explore the metabolic requirements for tolerance induction to human gamma globulin in the murine thymocyte. CBF1 (BALB/c × C57BL/6) mice were treated with a metabolic inhibitor and deaggregated HGG. Twenty-four hours later these mice were used as donors of thymus cells for irradiated recipients reconstituted with normal bone marrow cells. After a course of immunogenic HGG, the recipient animals were sacrificed and their immunocompetence assessed by use of the hemolytic plaque assay. It was determined that puromycin aminonucleoside (PAN), an inhibitor of RNA and protein synthesis, was capable of obviating tolerance induction in this system. This obviation was found to be temporal, and was not due to increased activity of the reticuloendothelial system. Radioautography revealed that these observed effects with PAN were not due to interference with specific interactions at the cellular membrane. The possible role of PAN in this system is discussed.  相似文献   
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A procedure is described for the simultaneous isolation, separation, and quantitation of S-adenosylmethionine (AdoMet) and S-adenosylethionine (AdoEt) in rat liver. These compounds are isolated by precipitation with ammonium reineckate, are separated by thin-layer chromatography, and are quantitated by an isotope dilution determination. The procedure was tested with commercial standards added to liver homogenate ranging up to 160 μg AdoMet/g liver and 173 μg AdoEt/g liver; at all of the concentrations tested, the recoveries were linear and accurate. AdoMet recoveries were linear in the presence of 11.6 or 307 μg AdoEt/g liver, and AdoEt recoveries were linear in the presence of 37.8 or 191 μg AdoMet/g liver. AdoMet and AdoEt levels were measured in the livers of rats fed diet containing 0 or 0.3% dl-ethionine for 2 weeks. In the ethionine-treated animals, AdoMet concentrations were lower than in the controls; and, conversely, AdoEt increased from 0 to 259 μg/g liver.  相似文献   
828.
829.
Two new ascomycetes,Linocarpon angustatum sp. nov. andNeolinocarpon nypicola sp. nov., are described from petioles ofNypa fruticans in Malaysia.Linocarpon angustatum differs from species in the genus in having needle-shaped ascospores.Neolinocarpon nypicola differs from species in the genus in having filiform ascospores which gradually taper towards the ends, and ascomata developing within well developed stromata. These new species are compared with existing species and illustrated with interference light micrographs. The fungi known from aerial parts ofNypa fruticans are listed.  相似文献   
830.
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