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941.
Diane E. Darlington Chiu-Yueh Hung Jiahua Xie 《Plant Cell, Tissue and Organ Culture》2009,99(2):157-165
Agrobacterium
tumefaciens strain LBA4404 containing the plasmid pBI121, carrying the reporter gene uidA and the kanamycin resistance gene nptII, was used for gene transfer experiments in selenium (Se)-hyperaccumulator Astragalus racemosus. The effects of kanamycin on cell growth and division and acetosyringone on transformation efficiency were evaluated. The
optimal concentration of kanamycin that could effectively inhibit cell growth and division in non-transgenic tissues was 50 mg l−1 and thus all putative transgenic plants were obtained on induction medium containing 50 mg l−1 kanamycin. The verification of transformants was achieved by both histochemical GUS assay and PCR amplification of nptII gene. Southern blot analysis was performed to further confirm that transgene nptII was stably integrated into the A. racemosus genome. A transformation frequency of approximately 10% was achieved using this protocol, but no beneficial effect from the
addition of acetosyringone (50 μM) was observed. This transformation system will be a useful tool for future studies of genes
responsible for Se-accumulation in A. racemosus. 相似文献
942.
Independence of stem and leaf hydraulic traits in six Euphorbiaceae tree species with contrasting leaf phenology 总被引:1,自引:0,他引:1
Hydraulic traits and hydraulic-related structural properties were examined in three deciduous (Hevea brasiliensis, Macaranga denticulate, and Bischofia javanica) and three evergreen (Drypetes indica, Aleurites moluccana, and Codiaeum variegatum) Euphorbiaceae tree species from a seasonally tropical forest in south-western China. Xylem water potential at 50% loss of
stem hydraulic conductivity (P50stem) was more negative in the evergreen tree, but leaf water potential at 50% loss of leaf hydraulic conductivity (P50leaf) did not function as P50stem did. Furthermore, P50stem was more negative than P50leaf in the evergreen tree; contrarily, this pattern was not observed in the deciduous tree. Leaf hydraulic conductivity overlapped
considerably, but stem hydraulic conductivity diverged between the evergreen and deciduous tree. Correspondingly, structural
properties of leaves overlapped substantially; however, structural properties of stem diverged markedly. Consequently, leaf
and stem hydraulic traits were closely correlated with leaf and stem structural properties, respectively. Additionally, stem
hydraulic efficiency was significantly correlated with stem hydraulic resistance to embolism; nevertheless, such a hydraulic
pattern was not found in leaf hydraulics. Thus, these results suggest: (1) that the evergreen and deciduous tree mainly diverge
in stem hydraulics, but not in leaf hydraulics, (2) that regardless of leaf or stem, their hydraulic traits result primarily
from structural properties, and not from leaf phenology, (3) that leaves are more vulnerable to drought-induced embolism than
stem in the evergreen tree, but not always in the deciduous tree and (4) that there exists a trade-off between hydraulic efficiency
and safety for stem hydraulics, but not for leaf hydraulics. 相似文献
943.
Mandana Nikpour Dafna D Gladman Dominique Ibanez Paula J Harvey Murray B Urowitz 《Arthritis research & therapy》2010,12(3):R125
Introduction
Total cholesterol (TC) and blood pressure (BP) are likely to take a dynamic course over time in patients with systemic lupus erythematosus (SLE). This would have important implications in terms of using single-point-in-time measurements of these variables to assess coronary artery disease (CAD) risk. The objective of this study was to describe and quantify variability over time of TC and BP among patients with SLE and to determine their correlates. 相似文献944.
Diclofenac sodium is known to interfere with renal physiology by inhibiting prostaglandins. Previous studies indicate that various nephrotoxins damage proximal renal tubules by altering alkaline phosphatase (APase) activity. APase has been reported to be a function related marker in renal proximal tubular epithelia where it is highly expressed. Present investigation deals with toxicity caused in mice kidney at histological and biochemical levels after diclofenac administration. Diclofenac toxicity was assessed by localizing APase in kidney histochemically and biochemically. Intramuscular diclofenac administration (10 mg/kg/body wt) for 30 days exhibited substantial degeneration in kidney. A marked change in APase activity was observed in histochemical and biochemical studies. A change was noticed in specific activity of APase at different periods of diclofenac treatment. Decrease in specific activity of APase after 10 days (18.41 %) and 30 days (55.3 %) of diclofenac exposure was observed. However, an insignificant hike in APase was observed after 20 days of drug therapy. Similar trends in APase activity were evidenced by the electrophoretic analysis. Histological and ultrastructural observations also corroborated above mentioned findings. Present investigation gives an insight into probable mechanism of renal pathology caused by diclofenac administration in mice. 相似文献
945.
946.
Jason J. Kolbe Johanna E. Wegener Yoel E. Stuart Ushuaia Milstead Katherine E. Boronow Alexis S. Harrison Jonathan B. Losos 《Biological invasions》2017,19(7):1989-1998
Human-mediated dispersal has reshaped distribution patterns and biogeographic relationships for many taxa. Long-distance and over-water dispersal were historically rare events for most species, but now human activities can move organisms quickly over long distances to new places. A potential consequence of human-mediated dispersal is the eventual reintroduction of individuals from an invasive population back into their native range; a dimension of biological invasion termed “cryptic back-introduction.” We investigated whether this phenomenon was occurring in the Cayman Islands where brown anole lizards (Anolis sagrei) with red dewlaps (i.e., throat fans), either native to Little Cayman or invasive on Grand Cayman, have been found on Cayman Brac where the native A. sagrei have yellow dewlaps. Our analysis of microsatellite data shows strong population-genetic structure among the three Cayman Islands, but also evidence for non-equilibrium. We found some instances of intermediate multilocus genotypes (possibly 3–9% of individuals), particularly between Grand Cayman and Cayman Brac. Furthermore, analysis of dewlap reflectance data classified six males sampled on Cayman Brac as having red dewlaps similar to lizards from Grand Cayman and Little Cayman. Lastly, one individual from Cayman Brac had an intermediate microsatellite genotype, a red dewlap, and a mtDNA haplotype from Grand Cayman. This mismatch among genetic and phenotypic data strongly suggests that invasive A. sagrei from Grand Cayman are interbreeding with native A. sagrei on Cayman Brac. To our knowledge, this is the first evidence of cryptic back-introduction. Although we demonstrate this phenomenon is occurring in the Cayman Islands, assessing its frequency there and prevalence in other systems may prove difficult due to the need for genetic data in most instances. Cryptic back-introductions may eventually provide some insight into how lineages are changed by the invasion process and may be an underappreciated way in which invasive species impact native biodiversity. 相似文献
947.
Yong-Yeon Jo Sang-Wook Kim Sung-Woo Cho Duck-Ho Bae Hyunok Oh 《Cluster computing》2017,20(2):1155-1166
An intuitive way to process the big data efficiently is to reduce the volume of data transferred over the storage interface to a host system. This is the reason that the notion of intelligent SSD (iSSD) was proposed to give processing power to SSD. There is rich literature on iSSD, however, its real implementation has not been provided to the public yet. Most prior work aims to quantify the benefits of iSSD with analytical modeling. In this paper, we first develop on iSSD simulator and present the potential of iSSD in data mining through the iSSD simulator. Our iSSD simulator performs on top of the gem 5 simulator and fully simulates all the processes of data mining algorithms running in iSSD with cycle-level accuracy. Then, we further addresse how to exploit all the computing resources for efficient processing of data mining algorithms. These days, CPU, GPU, and SSD are recently equipped together in most computing environment. If SSD is replaced with iSSD later on, we have a new computing environment where the three computing resources collaborate one another to process big data quite effectively. For this, scheduling is required to decide which computing resource is going to run for which function at which time. In our heterogeneous scheduling, types of computing resources, memory sizes in computing resources, and inter-processor communication times including IO time in SSD are considered. Our scheduling results show that processing in the collaborative environment outperforms that in the traditional one by up to about 10 times. 相似文献
948.
949.
Objectives
With the view of designing a single biocatalyst for biorefining, carbazole dioxygenase was cloned from Pseudomonas sp. and expressed in Rhodococcus sp.Results
The recombinant, IGTS8, degraded both carbazole and dibenzothiophene at 400 mg/l in 24 h. Maximum carbazole degradation was in 1:1 (v/v) hexadecane/aqueous phase. Anthracene, phenanthrene, pyrene, fluoranthene and fluorine were also degraded without affecting the aliphatic component.Conclusions
Recombinant Rhodococcus sp. IGTS8 can function as a single biocatalyst for removing major contaminants of fossil fuels viz. dibenzothiophene, carbazole and polyaromatic compounds.950.
Dongping Mo Daheng Yang Xuelian Xiao Ruihong Sun Lei Huang Jian Xu 《Biotechnology letters》2017,39(5):701-710