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Freshly prepared human red blood cells incubated with 5 mM ferricyanide, 0.2 mM iodoacetate and 2 mM adenosine in the presence of 5 mM EGTA demonstrate comparable increases in Na+ and K+ permeability (ferricyanide effect). This effect is unrelated to the Ca2+-activated K+ channel (Gardos effect) since influx of Ca2+ from outside the cell is excluded. Also this effect is different from the non-specific Na+ and K+ permeability change elicited by PCMBS. These differences become obvious by using various reagents. For example, A23187 and quinidine exert opposite effects in Gardos and ferricyanide experiments, where A23187 and atebrin react oppositely in the latter and in PCMBS experiments. The ferricyanide effect described here does not involve formation of nonspecific channels. The change in Na+ permeability separately from K+ permeability under certain circumstances suggests a more specific effect. 相似文献
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In Rhizobium japonicum the nitrogenase genes nifH and nifDK are separated. 总被引:9,自引:5,他引:4 下载免费PDF全文
In contrast to Klebsiella pneumoniae or fast-growing Rhizobium species, such as R. meliloti, where the nitrogenase structural genes are clustered in one operon (nifHDK), in slow-growing Rhizobium japonicum 110, nifH and nifDK are on separate operons. 相似文献
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Symmetrical dysplasia of the elbow joint and humero-radial synostosis together with brachymesophalangism, shortening of metacarpale I, and synostosis of carpal and tarsal bones in a boy, his mother and most probably also his grandmother is described. The combined malformations resemble closely those reported in a father and his daughter by Joachimsthal and in a father and his son by Mouchet and Saint-Pierre. It is suggested that this may represent a distinct hereditary entity.
Kommissarischer Direktor: Prof. Dr. G. Jentschura 相似文献
Kommissarischer Direktor: Prof. Dr. G. Jentschura 相似文献
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Reviewers for 1988 and 1989 相似文献
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Soybean response to nodulation by rhizobitoxine-producing bradyrhizobia as influenced by nitrate application 总被引:1,自引:0,他引:1
Foliar chlorosis of soybean (Glycine max [L.] Merr.) resulting from nodulation by rhizobitoxine-producing (RT+) strains of Bradyrhizobium japonicum is commonly less severe in the field than under greenhouse conditions. Differences in nutritional conditions between the field and greenhouse may contribute to this phenomenon. In particular, field-grown plants obtain some N from soil sources, whereas in the greenhouse soybean is often grown in low-N rooting media to emphasize symbiotic responses. Therefore, we examined the effect of NO3
- on the expression of RT-induced symptoms. Soybean plants inoculated with RT+ bradyrhizobia were grown for 42 days in horticultural vermiculite receiving nutrient solution amended with 0.0, 2.5, or 7.5 mM KNO3. Foliar chlorosis decreased with increasing NO3
- application whereas nodule mass per plant was generally increased by NO3
- application. Total amounts of nodular RT remained constant or increased with NO3
- application, but nodular concentrations of RT decreased. Chlorosis severity was negatively correlated with shoot dry weight, chlorophyll concentration, and total shoot N content. It was concluded that application of NO3
- can reduce the negative effects of RT production on the host plant. This suggests that any NO3
- present in field soils may serve to limit chlorosis development in soybeans.Abbreviations RT
rhizobitoxine
- RT+
rhizobitoxine-producing
- Lb
leghemoglobin
Published as Miscellaneous Paper No. 1429 of the Delaware Agricultural Experiment Station. 相似文献
10.
J. Reiss U. Ellermeyer M. Schloesser W. Fuhrmann D. Drews H. G. Posselt 《Human genetics》1993,91(1):78-79
Two adult sisters affected by cystic fibrosis were both shown to carry two different alterations within exon 11 of the CFTR gene, the nonsense mutation G542X and the missense mutation G551D. Both patients exhibit a relatively benign clinical course. In the described patients, G542X functions as a mild allele and is, in this respect, dominant to the severe G551D. 相似文献