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91.
Quahir Sohail Tomoe Inoue Hiroyuki Tanaka Amin Elsadig Eltayeb Yoshihiro Matsuoka Hisashi Tsujimoto 《Breeding Science》2011,61(4):347-357
Few genes are available to develop drought-tolerant bread wheat (Triticum aestivum L.) cultivars. One way to enhance bread wheat’s genetic diversity would be to take advantage of the diversity of wild species by creating synthetic hexaploid wheat (SW) with the genomic constitution of bread wheat. In this study, we compared the expression of traits encoded at different ploidy levels and evaluated the applicability of Aegilops tauschii drought-related traits using 33 Ae. tauschii accessions along with their corresponding SW lines under well-watered and drought conditions. We found wide variation in Ae. tauschii, and even wider variation in the SW lines. Some SW lines were more drought-tolerant than the standard cultivar Cham 6. Aegilops tauschii from some regions gave better performing SW lines. The traits of Ae. tauschii were not significantly correlated with their corresponding SW lines, indicating that the traits expressed in wild diploid relatives of wheat may not predict the traits that will be expressed in SW lines derived from them. We suggest that, regardless of the adaptability and performance of the Ae. tauschii under drought, production of SW could probably result in genotypes with enhanced trait expression due to gene interactions, and that the traits of the synthetic should be evaluated in hexaploid level. 相似文献
92.
Oya T Enoki T Grosberg AY Masamune S Sakiyama T Takeoka Y Tanaka K Wang G Yilmaz Y Feld MS Dasari R Tanaka T 《Science (New York, N.Y.)》1999,286(5444):1543-1545
A general approach is presented for creating polymer gels that can recognize and capture a target molecule by multiple-point interaction and that can reversibly change their affinity to the target by more than one order of magnitude. The polymers consist of majority monomers that make the gel reversibly swell and shrink and minority monomers that constitute multiple-point adsorption centers for the target molecule. Multiple-point interaction is experimentally proven by power laws found between the affinity and the concentration of the adsorbing monomers within the gels. 相似文献
93.
Kobayashi N Fujiwara T Westerman KA Inoue Y Sakaguchi M Noguchi H Miyazaki M Cai J Tanaka N Fox IJ Leboulch P 《Science (New York, N.Y.)》2000,287(5456):1258-1262
Because of a critical shortage in suitable organs, many patients with terminal liver disease die each year before liver transplantation can be performed. Transplantation of isolated hepatocytes has been proposed for the temporary metabolic support of patients awaiting liver transplantation or spontaneous reversion of their liver disease. A major limitation of this form of therapy is the present inability to isolate an adequate number of transplantable hepatocytes. A highly differentiated cell line, NKNT-3, was generated by retroviral transfer in normal primary adult human hepatocytes of an immortalizing gene that can be subsequently and completely excised by Cre/Lox site-specific recombination. When transplanted into the spleen of rats under transient immunosuppression, reversibly immortalized NKNT-3 cells provided life-saving metabolic support during acute liver failure induced by 90% hepatectomy. 相似文献
94.
Tumor immunity produced by the intradermal inoculation of living tumor cells and living Mycobacterium bovis (strain BCG) 总被引:9,自引:0,他引:9
The intradermal inoculation of mixtures containing living tumor cells and living Mycobacterium bovis (strain BCG) into unimmunized syngeneic guinea pigs results in an inflammatory reaction to the BCG, and there is no progressive tumor growth. In the absence of BCG the tumor grows progressively, metastasizes, and kills the animal. By conventional methods, it has not been possible to immunize syngeneic guinea pigs to the tumor used. Guinea pigs that receive mixtures of BCG and tumor cells, however, develop specific systemic tumor immunity as measured by delayed cutaneous hypersensitivity and by suppression of tumor growth. 相似文献
95.
Multiple principal sigma factor homologs in eubacteria: identification of the "rpoD box" 总被引:23,自引:0,他引:23
Genes for the principal sigma factor (rpoD genes) of various eubacteria were identified with a synthetic oligonucleotide probe corresponding to a conserved sequence in rpoD gene products of Escherichia coli and Bacillus subtilis. Multiple rpoD homologs were found in the strains of Micrococcus, Pseudomonas, and Streptomyces, whereas single genes were detected in E. coli, B. subtilis, and Staphylococcus aureus. The four rpoD homologs of Streptomyces coelicolor A3(2) were cloned and sequenced. A homologous portion with 13 amino acids was found in the rpoD genes of S. coelicolor A3(2), E. coli, and B. subtilis and was named the "rpoD box." 相似文献
96.
Rats maintained on a low phosphorus diet supplemented with 25-hydroxyvitamin D(3) show high intestinal calcium transport activity as compared to rats similarly treated but fed a diet containing adequate phosphorus. This increased transport activity is correlated with an increased biosynthesis of 1,25-dihydroxyvitamin D(3), the probable metabolically active form of the vitamin in the intestine. 相似文献
97.
Wahlen M Tanaka N Henry R Deck B Zeglen J Vogel JS Southon J Shemesh A Fairbanks R Broecker W 《Science (New York, N.Y.)》1989,245(4915):286-290
Measurements of carbon-14 in small samples of methane from major biogenic sources, from biomass burning, and in "clean air" samples from both the Northern and Southern hemispheres reveal that methane from ruminants contains contemporary carbon, whereas that from wetlands, pat bogs, rice fields, and tundra is somewhat, depleted in carbon-14. Atmospheric (14)GH(4) seems to have increased from 1986 to 1987, and levels at the end of 1987 were 123.3 +/- 0.8 percent modern carbon (pMC) in the Northern Hemisphere and 120.0 +/- 0.7 pMC in the Southern Hemisphere. Model calculations of source partitioning based on the carbon-14 data, CH(4) concentrations, and delta(13)C in CH(4) indicate that 21 +/- 3% of atmospheric CH(4) was derived from fossil carbon at the end of 1987. The data also indicate that pressurized water reactors are an increasingly important source of (14)CH(4). 相似文献
98.
Earth tides can trigger shallow thrust fault earthquakes 总被引:6,自引:0,他引:6
We show a correlation between the occurrence of shallow thrust earthquakes and the occurrence of the strongest tides. The rate of earthquakes varies from the background rate by a factor of 3 with the tidal stress. The highest correlation is found when we assume a coefficient of friction of mu = 0.4 for the crust, although we see good correlation for mu between 0.2 and 0.6. Our results quantify the effect of applied stress on earthquake triggering, a key factor in understanding earthquake nucleation and cascades whereby one earthquake triggers others. 相似文献
99.
Hanayama R Tanaka M Miyasaka K Aozasa K Koike M Uchiyama Y Nagata S 《Science (New York, N.Y.)》2004,304(5674):1147-1150
Apoptotic cells expose phosphatidylserine and are swiftly engulfed by macrophages. Milk fat globule epidermal growth factor (EGF) factor 8 (MFG-E8) is a protein that binds to apoptotic cells by recognizing phosphatidylserine and that enhances the engulfment of apoptotic cells by macrophages. We report that tingible body macrophages in the germinal centers of the spleen and lymph nodes strongly express MFG-E8. Many apoptotic lymphocytes were found on the MFG-E8-/- tingible body macrophages, but they were not efficiently engulfed. The MFG-E8-/- mice developed splenomegaly, with the formation of numerous germinal centers, and suffered from glomerulonephritis as a result of autoantibody production. These data demonstrate that MFG-E8 has a critical role in removing apoptotic B cells in the germinal centers and that its failure can lead to autoimmune diseases. 相似文献
100.
Periodic signaling controlled by an oscillatory circuit that includes protein kinases ERK2 and PKA 总被引:1,自引:0,他引:1
Maeda M Lu S Shaulsky G Miyazaki Y Kuwayama H Tanaka Y Kuspa A Loomis WF 《Science (New York, N.Y.)》2004,304(5672):875-878
Self-regulating systems often use robust oscillatory circuits. One such system controls the chemotactic signaling mechanism of Dictyostelium, where pulses of adenosine 3',5'-monophosphate (cAMP) are generated with a periodicity of 7 minutes. We have observed spontaneous oscillations in activation of the mitogen-activated protein (MAP) kinase ERK2 that occur in phase with peaks of cAMP, and we show that ERK2 modulates cAMP levels through the phosphodiesterase RegA. Computer modeling and simulations of the underlying circuit faithfully account for the ability of the cells to spontaneously generate periodic pulses during specific stages of development. Similar oscillatory processes may occur in cells of many different species. 相似文献