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181.
Jorge F. Pereira Gaofeng Zhou Emmanuel Delhaize Terese Richardson Meixue Zhou Peter R. Ryan 《Annals of botany》2010,106(1):205-214
MethodsParticle bombardment was used to transform wheat with TaALMT1, the Al3+ resistance gene from wheat, using the maize ubiquitin promoter to drive expression. TaALMT1 expression, malate efflux and Al3+ resistance were measured in the T1 and T2 lines and compared with the parental line and an Al3+-resistant reference genotype, ET8.ConclusionsThe Al3+ resistance of wheat was increased by enhancing TaALMT1 expression with biotechnology. This is the first report of a major food crop being stably transformed for greater Al3+ resistance. Transgenic strategies provide options for increasing food supply on acid soils. 相似文献
182.
A muscle-specific intron enhancer required for rescue of indirect flight muscle and jump muscle function regulates Drosophila tropomyosin I gene expression. 总被引:4,自引:0,他引:4 下载免费PDF全文
The control of expression of the Drosophila melanogaster tropomyosin I (TmI) gene has been investigated by P-element transformation and rescue of the flightless and jumpless TmI mutant strain, Ifm(3)3. To localize cis-acting DNA sequences that control TmI gene expression, Ifm(3)3 flies were transformed with P-element plasmids containing various deletions and rearrangements of the TmI gene. The effects of these mutations on TmI gene expression were studied by analyzing both the extent of rescue of the Ifm(3)3 mutant phenotypes and determining TmI RNA levels in the transformed flies by primer extension analysis. The results of our analysis indicate that a region located within intron 1 of the gene is necessary and sufficient for directing muscle-specific TmI expression in the adult fly. This intron region has characteristics of a muscle regulatory enhancer element that can function in conjunction with the heterologous nonmuscle hsp70 promoter to promote rescue of the mutant phenotypes and to direct expression of an hsp70-Escherichia coli lacZ reporter gene in adult muscle. The enhancer can be subdivided further into two domains of activity based on primer extension analysis of TmI mRNA levels and on the rescue of mutant phenotypes. One of the intron domains is required for expression in the indirect flight muscle of the adult. The function of the second domain is unknown, but it could regulate the level of expression or be required for expression in other muscle. 相似文献
183.
Alissa D. Guarnaccia Kristie L. Rose Jing Wang Bin Zhao Tessa M. Popay Christina E. Wang Kiana Guerrazzi Salisha Hill Chase M. Woodley Tyler J. Hansen Shelly L. Lorey J. Grace Shaw William G. Payne April M. Weissmiller Edward T. Olejniczak Stephen W. Fesik Qi Liu William P. Tansey 《Cell reports》2021,34(3):108636
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BACKGROUND: Over the past 20 years, there have been marked increases in rates of coronary artery bypass grafting (CABG) among older people in Canada. The objectives of this study were to accurately estimate the direct medical costs of CABG in older patients (age 65 years or more) and to compare CABG costs for this age group with those for patients less than 65 years of age. METHODS: Direct medical costs were estimated from a sample of 205 older and 202 younger patients with triple-vessel or left main coronary artery disease who underwent isolated CABG at The Toronto Hospital, a tertiary care university-affiliated hospital, between Apr. 1, 1991, and Mar. 31, 1992. Costs are expressed in 1992 Canadian dollars from a third-party payer perspective. RESULTS: The mean costs of CABG in older and younger patients respectively were $16,500 and $15,600 for elective, uncomplicated cases, $23,200 and $19,200 for nonelective, uncomplicated cases, $29,200 and $20,300 for elective, complicated cases, and $33,600 and $23,700 for nonelective, complicated cases. Age remained a significant determinant of costs after adjustment for severity of heart disease and for comorbidity. Between 59% and 91% of the cost difference between older and younger patients was accounted for by higher intensive care unit and ward costs. INTERPRETATION: CABG was more costly in older people, especially in complicated cases, even after an attempt to adjust for severity of disease and comorbidity. Future studies should attempt to identify modifiable factors that contribute to longer intensive care and ward stays for older patients. 相似文献
187.
The extent to which veterinary pathogenic and human opportunistic species of thermophilic and thermotolerant fungi disseminate in aerosols from heated effluents of nuclear production reactors of the Savannah River Plant (SRP), South Carolina, has been measured. Aerosol samples were taken at 140 sites, from directly over thermal effluents to more than 100 kilometers from the SRP boundary. Sampling methods included settle plates (134 sites, 1, 103 plates for a total of 2, 805 hrs.), liquid impingement (78 sites, 1 cubic meter each), filtration (79 sites, 1 cubic meter each), and a particle sizing cascade impactor (Andersen Sampler) (17 sites, 1 cubic meter each). Soils, foams, and microbial mats from thermal effluents (a total of 191 samples), and vegetation (560 samples) were sampled to study distribution of particular species. Sampling was done under a variety of conditions: hot weather and cold, wet and dry, day and night, windy and calm, reactor(s) operating and not, disturbed vegetation and undisturbed. At 102 of the aerosol sampling sites, sophisticated meterological analyses were used to allow sampling of air in the plume which originated from thermal effluents. Soil, foam, microbial mat, vegetation, and aerosol samples were quantitatively plated for detection of viable units; filters were halved and then both plated and observed microscopically.Significant dissemination of thermophilic and thermotolerant fungi from thermal effluents was not detected. Thermophilic and thermotolerant fungi were widely distributed in soil, air, and on vegetation. Dactylaria gallopava, the indicator species and dominant fungus in microbial mats lining SRP thermal effluents and the cause of epidemic fatal phaeohyphomycosis in flocks of turkeys and chickens in South Carolina, Georgia, and elsewhere, was isolated from air at a maximum of 50 meters from effluents (8 viable units per cubic meter of air in the plume of an effluent during a strong wind).By acceptance of this paper, the publisher and/or recipient acknowledges that the U.S. Government's right to retain a nonexclusive, royalty-free license in and to any copyright covering this paper, along with the right to reproduce and to authorize others to reproduce all or part of the copyrighted paper. 相似文献
188.
Studies of biological responses to moonlight as distinct from lunar phases are warranted. Fungi are especially suitable organisms for this research. Moonlight is quantitatively and qualitatively similar to light which causes photoresponses of fungi. 相似文献
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Kenneth A. Marx Terese Denial Theodore Keller 《Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression》1984,783(3):283-292
We have examined aspects of the interaction of cycled microtubule protein preparations with 35S-labeled mouse DNA tracer in a competition system with unlabelled competitor E. coli or mouse DNA. The nitrocellulose filter binding assay was used to measure interaction by scintillation counting. DNA molecular weight affected the levels of filter retained 35S-labelled mouse tracer DNA. Filter retention levels increased if 35S-labelled mouse DNA tracer size was increased, and the filter binding level decreased if competitor DNA size was increased. There was a sizeable, reproducible difference in the 35S-labelled mouse DNA tracer binding level of about 1% when E. coli or mouse DNA competitors were compared. Mouse DNA more effectively competed with 35S-labelled mouse DNA for microtubule protein binding than did E. coli DNA, suggesting that a small class of higher-organism DNA sequences interacts very strongly with microtubule protein. From other studies we know this to be the MAP fraction (Marx, K.A. and Denial, T. (1984) in The Molecular Basis of Cancer (Rein, R., ed.), Alan R. Liss, New York, in the press; and Villasante, E., Corces, V.G., Manso-Martinez, R. and Avila, J. (1981) Nucleic Acids Res. 9, 895–908). We find that this difference in competitor DNA strength is qualitatively similar under high-stringency conditions (0.5 M NaCl, high competitor [DNA]) we developed for examining high-affinity complexes. Under high-stringency conditions we isolated 1.2% and 0.6% of 35S-labelled mouse DNA at 4200 and 350 bp respective sizes as nitrocellulose filter bound DNA-protein complexes. At both molecular weights these high-affinity DNA sequences, isolated from the filters, were shown to be significantly enriched in repetitive DNA sequences by S1 nuclease solution reassociation kinetics. The kinetics are consistent with about a 4-fold mouse satellite DNA enrichment as well as enrichment in other repetitious DNA sequence classes. The high molecular weight filter-bound DNA samples were sedimented to equilibrium in CsCl buoyant density gradients and found to contain primarily mouse satellite DNA density sequences (1.691 g/cm3) with some minor fractions at other density positions (1.670, 1.682, 1.705, 1.740, 1.760 g/cm3) similar to those observed by our laboratory in previous investigations of micrococcal nuclease-resistant chromatin (Marx, K.A. (1977) Biochem. Biophys. Res. Commun. 78, 777–784). That the high-affinity microtubule-bound DNA was some 3–5-fold enriched in mouse satellite sequences was demonstrated by its characteristic BstNI restriction enzyme cleavage pattern 相似文献