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51.
Oil presence in soil, as a stressor, reduces phytoremediation efficiency through an increase in the plant stress ethylene. Bacterial 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, as a plant stress ethylene reducer, was employed to increase oil phytoremediation efficiency. For this purpose, the ability of ACC deaminase-producing Pseudomonas strains to grow in oil-polluted culture media and withstand various concentrations of oil and also their ability to reduce plant stress ethylene and enhance some growth characteristics of maize and finally their effects on increasing phytoremediation efficiency of poly aromatic hydrocarbons (PAHs) in soil were investigated. Based on the results, of tested strains just P9 and P12 were able to perform oil degradation. Increasing oil concentration from 0 to 10% augmented these two strains population, 15.7% and 12.9%, respectively. The maximum increase in maize growth was observed in presence of P12 strain. Results of high-performance liquid chromatography (HPLC) revealed that PAHs phytoremediation efficiency was higher for inoculated seeds than uninoculated. The highest plant growth and PAHs removal percentage (74.9%) from oil-polluted soil was observed in maize inoculated with P12. These results indicate the significance of ACC deaminase producing bacteria in alleviation of plant stress ethylene in oil-polluted soils and increasing phytoremediation efficiency of such soils.  相似文献   
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Both kidneys of mature pigs received a single dose of 9.8 Gy 60Co gamma rays. Pigs were killed between 2 and 24 weeks after irradiation and the kidneys examined histologically. Glomerular and tubular changes were observed within 2 weeks of irradiation. Neutrophils and other leukocytes were seen within glomerular capillary loops; mesangial matrix and cell number increased. A progressive increase in thickening of the basement membrane and a decrease in capillary lumina were then noted. Basement membrane duplication occurred within 12 weeks. By 24 weeks these lesions had increased in severity, sclerotic endstage glomeruli, predominantly subcapsular or juxtamedullary, being evident. Tubular lesions initially consisted of focal areas of tubular atrophy in the juxtamedullary region. By 6 weeks subcapsular foci of tubular degeneration, regeneration, and necrosis were found; these appeared to resolve 12 weeks after irradiation. At later times the severity of the tubular lesions varied between pigs, with some exhibiting interstitial fibrosis involving a complete band of subcapsular tissue, while others showed relatively mild changes. There was no apparent change in the vasculature. These findings indicate that (a) there is no one target or dose-limiting cell, and (b) the vasculature does not play a primary role in the development of radiation nephropathy.  相似文献   
54.
The purpose of the present investigation was to produce erythritol by Yarrowia lipolytica mutant without any by-products. Mutants of Y. lipolytica were generated by ultra-violet for enhancing erythrose reductase (ER) activity and erythritol production. The mutants showing the highest ER activity were screened by triphenyl tetrazolium chloride agar plate assay. Productivity of samples was analyzed by thin-layer chromatography and high-performance liquid chromatography equipped with the refractive index detector. One of the mutants named as mutant 49 gave maximum erythritol production without any other by-products (particularly glycerol). Erythritol production and specific ER activity in mutant 49 increased to 1.65 and 1.47 times, respectively, in comparison with wild-type strain. The ER gene of wild and mutant strains was sequenced and analyzed. A general comparison of wild and mutant gene sequences showed the replacement of Asp270 with Glu270 in ER protein. In order to enhance erythritol production, we used a three component-three level-one response Box–Behnken of response surface methodology model. The optimum medium composition for erythritol production was found to be (g/l) glucose 279.49, ammonium sulfate 9.28, and pH 5.41 with 39.76 erythritol production.  相似文献   
55.
Chemical investigation of insect antifeedants from the bitter tasting leaves of Vernonia amygdalina by the application of semi-preparative reversed  相似文献   
56.
A Rezvani  J P Huidobro-Toro  E L Way 《Life sciences》1982,31(20-21):2367-2370
The rate and degree of in vitro tolerance development to morphine, normorphine and d,1-methadone were assessed on the excised guinea pig ileum. Agonists in fixed concentrations at 1/4, 1/2, 1 and 2 x IC50 were incubated with the tissue for 1, 2 or 4 hours. The degree of tolerance development was expressed as a ratio of the IC50 after and before incubation. A high degree of tolerance developed to all three agonists and the effect could be prevented by co-incubation with naloxone. Tolerance development was stereo-specific; levorphanol and 1-methadone developed much higher degrees of tolerance than their respective d-isomers. Furthermore, under the same conditions, subsensitivity to acetylcholine, norepinephrine, and adenosine monophosphate did not develop. The in vitro tolerance was accompanied by physical dependence development as evidenced by the fact that naloxone elicited muscular contracture in the tolerant ileum. cAMP enhanced the development of tolerance to normorphine and cycloheximide could reduce this phenomenon. It is concluded that the procedure may facilitate studies on the mechanisms involved in the development of opiate tolerance and physical dependence.  相似文献   
57.
We have systematically investigated six compendial nonionic detergents as potential replacements for Triton ×-100 in bioprocessing applications. Use of compendial raw materials in cGMP bioprocessing is advantageous for a variety of reasons including material specifications developed to meet stringent pharmaceutical product quality requirements, regulatory familiarity and comfort, and availability from vendors experienced supplying the biopharmaceutical industry. We first examine material properties of the detergents themselves including melting point and viscosity. Process performance and product contact in real-world bioprocess applications are then investigated. Lastly, we test the detergents in virus inactivation (VI) experiments with recombinant proteins and adeno-associated virus. Two of the detergents tested, PEG 9 Lauryl Ether and PEG 6 Caprylic/Capric Glycerides, showed favorable properties that make them attractive for use as potential Triton X-100 replacements. Process performance testing indicated negligible impact of the detergents on product yield, purity, and activity compared to a control with no detergent. Importantly, both PEG 9 Lauryl Ether and PEG 6 Caprylic/Capric Glycerides demonstrated very fast VI kinetics with complete inactivation of XMuLV observed in less than 1 min at a target 1% detergent concentration. Potential advantages and disadvantages of both candidate detergents for use in cGMP bioprocessing are summarized and discussed.  相似文献   
58.
Cluster Computing - Today, the use of fog computing is increasing due to the development of delay-sensitive applications in areas such as e-health, agriculture, and smart city management. In such...  相似文献   
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Peach and almond have been considered as model species for the family Rosaceae and other woody plants. Consequently, mapping and characterisation of genes in these species has important implications. High-resolution melting (HRM) analysis is a recent development in the detection of SNPs and other markers, and proved to be an efficient and cost-effective approach. In this study, we aimed to map genes corresponding to known proteins in other species using the HRM approach. Prunus unigenes were searched and compared with known proteins in the public databases. We developed single-nucleotide polymorphism (SNP) markers, polymorphic in a mapping population produced from a cross between the cloned cultivars Nonpareil and Lauranne. A total of 12 SNP-anchored putative genes were genotyped in the population using HRM, and mapped to an existing linkage map. These genes were mapped on six linkage groups, and the predicted proteins were compared to putative orthologs in other species. Amongst those genes, four were abiotic stress-responsive genes, which can provide a starting point for construction of an abiotic resistance map. Two allergy and detoxification related genes, respectively, were also mapped and analysed. Most of the investigated genes had high similarities to sequences from closely related species such as apricot, apple and other eudicots, and these are putatively orthologous. In addition, it was shown that HRM can be an effective means of genotyping populations for the purpose of constructing a linkage map. Our work provides basic genomic information for the 12 genes, which can be used for further genetic and functional studies.  相似文献   
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