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941.
The psbQ gene encoding a 16-kDa polypeptide of the oxygen-evolving complex of photosystem II has been isolated from Arabidopsis thaliana and characterized. The gene consists of a 28 nucleotide long leader sequence, two introns and three exons encoding a 223-amino-acid precursor polypeptide. The first 75 amino acids act as a transit peptide for the translocation of the polypeptide into the thylakoid lumen. Expression studies show that the gene is light-inducible and expresses only in green tissues with high steady-state mRNA levels in leaves. Using this gene as a probe, restriction fragment length polymorphism between two ecotypes, Columbia and Estland, has also been detected. 相似文献
942.
943.
M. Gopalakrishnan P. Sureshkumar J. Thanusu V. Kanagarajan 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):347-351
Compound 26 is more potent against Escherichia coli. and 24 is more active against Staphylococcus aureus, β-Heamolytic streptococcus, Vibreo cholerae, Salmonella typhii, and Shigella flexneri than the standard drug ciprofloxacin. Moreover, of all the compounds tested, 26 is more effective against Aspergillus flavus and Mucor, than the standard drug fluconazole. 相似文献
944.
Ivonne J. Garzn‐Ordua Shaun L. Winterton Yunlan Jiang Laura C.V. Breitkreuz Peter Duelli Michael S. Engel Norman D. Penny Catherine A. Tauber Atsushi Mochizuki Xingyue Liu 《Systematic Entomology》2019,44(3):499-513
We present a time‐calibrated phylogeny of the charismatic green lacewings (Neuroptera: Chrysopidae). Previous phylogenetic studies on the family using DNA sequences have suffered from sparse taxon sampling and/or limited amounts of data. Here we combine all available previously published DNA sequence data and add to it new DNA sequences generated for this study. We analysed these data in a supermatrix using Bayesian and maximum likelihood methods and provide a phylogenetic hypothesis for the family that recovers strong support for the monophyly of all subfamilies and resolves relationships among a large proportion of chrysopine genera. Chrysopinae tribes Leucochrysini and Belonopterygini were recovered as monophyletic sister clades, while the species‐rich tribe Chrysopini was rendered paraphyletic by Ankylopterygini. Relationships among the subfamilies were resolved, although with relatively low statistical support, and the topology varied based on the method of analysis. Greatest support was found for Apochrysinae as sister to Nothochrysinae and Chrysopinae, which is in contrast to traditional concepts that place Nothochrysinae as sister to the rest of the family. Divergence estimates suggest that the stem groups to the various subfamilies diverged during the Triassic‐Jurassic, and that stem groups of the chrysopine tribes diverged during the Cretaceous. 相似文献
945.
P S Simavorian D A Gevorkian I L Saakian A B Iordanian 《Biulleten' eksperimental'no? biologii i meditsiny》1987,103(3):310-312
It has been experimentally and clinically established that the determination of leucine-aminotransferase activity in the blood serum and abdominal exudate may serve as a marker for the early determination of pancreonecrosis and edematous (serous) pancreatitis. 相似文献
946.
Renal transport and metabolism of nicotinic acid 总被引:1,自引:0,他引:1
947.
948.
The phenotype of a ouabain-resistant Aedes albopictus cell line has been partially characterized. Treatment of ouabain-sensitive cells with 0.005-1.0 mM ouabain resulted in an 80% reduction in the uptake of 86rubidium (86Rb+), an ion with an affinity for the K+ pump binding site; ouabain-resistant cells showed only a 40% reduction with 1.0 mM ouabain. When ouabain-sensitive cells were incubated in the presence of ouabain (0.1 mM) for one and one-half to three hours, the molar ratio of intracellular Na+/K+ rose from 0.2 to 4.2. In ouabain-resistant cells, a similar treatment had very little effect. Based on [3H] ouabain-binding studies, ouabain-resistant cells were estimated to have 60% fewer binding sites per cell than ouabain-sensitive cells. The spontaneous mutation rate from ouabain sensitivity to ouabain resistance was calculated to be 1-6 x 10(-8) mutations/cell/generation, a value similar to that reported for mammalian cells at the analogous locus. 相似文献
949.
950.