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排序方式: 共有4609条查询结果,搜索用时 15 毫秒
901.
Ian Branford Shevaun Johnson Aspinas Chapwanya Samantha Zayas Filip Boyen Matylda Barbara Mielcarska Lidia Szulc-Dbrowska Patrick Butaye Felix Ngosa Toka 《International journal of molecular sciences》2021,22(13)
Dermatophilus congolensis is a bacterial pathogen mostly of ruminant livestock in the tropics/subtropics and certain temperate climate areas. It causes dermatophilosis, a skin disease that threatens food security by lowering animal productivity and compromising animal health and welfare. Since it is a prevalent infection in ruminants, dermatophilosis warrants more research. There is limited understanding of its pathogenicity, and as such, there is no registered vaccine against D. congolensis. To better understanding the genomics of D. congolensis, the primary aim of this work was to investigate this bacterium using whole-genome sequencing and bioinformatic analysis. D. congolensis is a high GC member of the Actinobacteria and encodes approximately 2527 genes. It has an open pan-genome, contains many potential virulence factors, secondary metabolites and encodes at least 23 housekeeping genes associated with antimicrobial susceptibility mechanisms and some isolates have an acquired antimicrobial resistance gene. Our isolates contain a single CRISPR array Cas type IE with classical 8 Cas genes. Although the isolates originate from the same geographical location there is some genomic diversity among them. In conclusion, we present the first detailed genomic study on D. congolensis, including the first observation of tet(Z), a tetracycline resistance-conferring gene. 相似文献
902.
903.
Elina Siirola Francesco G. Mutti Barbara Grischek Sebastian F. Hoefler Walter M. F. Fabian Gideon Grogan Wolfgang Kroutil 《Advanced Synthesis \u0026amp; Catalysis》2013,355(9):1703-1708
Prochiral bicyclic diketones were transformed to a single diastereomer of 3‐substituted cyclohexylamine derivatives via three consecutive biocatalytic steps. The two chiral centres were set up by a C C hydrolase (6‐oxocamphor hydrolase) in the first step and by an ω‐transaminase in the last step. The esterification of the intermediate keto acid was catalysed by a lipase in the second step if possible. For two substrates the C C hydrolytic step as well as the esterification could be run simultaneously in a one‐pot cascade in an organic solvent. In one example, the reaction mixture of the first two steps could be directly subjected to bio‐amination in an organic solvent without the need to change the reaction medium. Depending on the choice of the ω‐transaminase employed and the substrate the cis‐ as well as the trans‐diastereomers could be obtained in optically pure forms. 相似文献
904.
Mira Mandeljc Barbara Malič Marija Kosec Goran Dražič 《Integrated ferroelectrics》2013,141(1):329-338
The general problem of processing zirconium-rich lead-lanthanum-zirconate-titanate (PLZT) thin films at the commonly used temperatures between 600 and 650 C is lead-oxide loss, leading to the formation of a non-ferroelectric, surface pyrochlore-type phase. To avoid lead-oxide losses due to sublimation and/or the interaction of the film with the substrate, it is desirable that the annealing temperatures are as low as possible. Our goal was to study and prepare perovskite PLZT 9.5/65/35 (Pb 0.858 La 0.095 Zr 0.65 Ti 0.35 O 3 ) thin films below 500 C. At 400 C the growth of the perovskite phase follows the parabolic law typical of diffusion controlled processes. During prolonged annealing growth continues until the limiting stoichiometry of the perovskite phase with regard to the PbO is reached. We conclude that, even at this low temperature the amount of PbO in the film is the critical factor in the crystallization of the perovskite phase. 相似文献
905.
Vera Samburova Mark S. Lemos Sage Hiibel S. Kent Hoekman John C. Cushman Barbara Zielinska 《Journal of the American Oil Chemists' Society》2013,90(1):53-64
To assess the suitability of microalgal strains for biodiesel production the lipid content and composition, especially individual triacylglycerols (TAG) and free fatty acids (FFA) must be determined. In this study, the compositions and concentrations of TAG and FFA were analysed in four halophytic algal species, Dunaliella salina, D. tertiolecta, D. bardawil, and D. granulata. These species were selected as part of a larger screen to identify species suitable for biofuel feedstocks. An accelerated solvent extraction instrument was used for lipids and fatty acid extraction using a dichloromethane–hexane solvent system. Ultra-performance liquid chromatography coupled with mass spectrometry (MS) detection was optimized and applied to the quantitative analysis of TAG and FFA in the different algal extracts. Individual TAG were characterized structurally using direct electrospray ionization (ESI) MS and MS/MS techniques. Cationic adducts (NH4 +) of TAG were detected and quantified in the positive ESI MS and MS/MS modes, while the negative ESI mode was used for FFA analysis. Over 20 TAG were identified and quantified in the four Dunaliella strains. Analysis of FFA compositions demonstrated that the most abundant FFA in these four algal species were palmitic, linolenic, linoleic, and oleic acids. 相似文献
906.
Campbell Barbara K.; Fuller Bret E.; Lee Eun Sul; Tillotson Carrie; Woelfel Tiffany; Jenkins Lindsay; Robinson James; Booth Robert E.; McCarty Dennis 《Canadian Metallurgical Quarterly》2009,23(2):260
A multisite, randomized trial within the National Drug Abuse Treatment Clinical Trials Network (CTN) was conducted to test 3 interventions to enhance treatment initiation following detoxification: (a) a single session, therapeutic alliance intervention (TA) added to usual treatment; (b) a 2-session, counseling and education, HIV/HCV risk reduction intervention (C&E), added to usual treatment; and (c) treatment as usual (TAU) only. Injection drug users (n = 632) enrolled in residential detoxification at 8 community treatment programs were randomized to 1 of the 3 study conditions. TA participants reported entering outpatient treatment sooner and in greater numbers than TAU participants. Reported treatment entry for C&E fell between TA and TAU with no significant differences between C&E and the other conditions. There were no differences among the interventions in retention, as measured by weeks of outpatient treatment for all participants who reported treatment entry. Alliance building interventions appear to be effective in facilitating transfer from detoxification to outpatient treatment, but additional treatment engagement interventions may be necessary to improve retention. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
907.
Petra Milota Alain Duval Hélène Guicharnaud Silke Merchel Manfred Schreiner Elisabeth Thobois Barbara Wünschek 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2008,266(10):2279-2285
Silverpoint drawings from the Renaissance are among the most precious and rarest treasures of graphical art. Our research group is particularly interested in the analysis of silverpoint drawings by Albrecht Dürer (1471-1528). A very sensitive and non-destructive analytical method, either spatially resolved synchrotron-radiation induced X-ray fluorescence (SY-XRF) or proton-induced X-ray emission (PIXE), is needed to determine the chemical composition of the very faint silver marks on such drawings. Dürer drawings from the collection of the Albertina, Vienna, were analyzed to amend existing data on Dürer drawings. For this purpose an external-beam PIXE setup was installed at the Vienna Environmental Research Accelerator (VERA). It allows to analyze a spot of ∼0.15 mm on the object in air with 3 MeV protons, and to detect the emitted X-rays that are characteristic for the chemical composition with very good sensitivity and without harming the precious objects. After successful measurements on artificial test samples, four original silverpoint drawings were investigated: two portraits from Albrecht Dürer’s very early period (self-portrait and portrait of his father) and two drawings from Dürer’s sketch book of his travel to the Netherlands 1520/21. 相似文献
908.
909.
Merrill Lex L.; Thomsen Cynthia J.; Sinclair Barbara B.; Gold Steven R.; Milner Joel S. 《Canadian Metallurgical Quarterly》2001,69(6):992
Female Navy recruits (N=5,226) completed surveys assessing history of childhood sexual abuse (CSA), childhood strategies for coping with CSA, childhood parental support, and current psychological adjustment. Both CSA and parental support independently predicted later adjustment. In analyses examining whether CSA victims' functioning was associated with CSA severity (indexed by 5 variables), parental support (indexed by 3 variables), and coping (constructive, self-destructive, and avoidant), the negative coping variables were the strongest predictors. A structural equation model revealed that the effect of abuse severity on later functioning was partially mediated by coping strategies. However, contrary to predictions, the model revealed that childhood parental support had little direct or indirect impact on adult adjustment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
910.
Etienne Buscail Guillaume Le Cosquer Fabian Gross Marine Lebrin Laetitia Bugarel Cline Deraison Nathalie Vergnolle Barbara Bournet Cyrielle Gilletta Louis Buscail 《International journal of molecular sciences》2021,22(18)
Between 20 to 25% of Crohn’s disease (CD) patients suffer from perianal fistulas, a marker of disease severity. Seton drainage combined with anti-TNFα can result in closure of the fistula in 70 to 75% of patients. For the remaining 25% of patients there is room for in situ injection of autologous or allogenic mesenchymal stem cells such as adipose-derived stem/stromal cells (ADSCs). ADSCs exert their effects on tissues and effector cells through paracrine phenomena, including the secretome and extracellular vesicles. They display anti-inflammatory, anti-apoptotic, pro-angiogenic, proliferative, and immunomodulatory properties, and a homing within the damaged tissue. They also have immuno-evasive properties allowing a clinical allogeneic approach. Numerous clinical trials have been conducted that demonstrate a complete cure rate of anoperineal fistulas in CD ranging from 46 to 90% of cases after in situ injection of autologous or allogenic ADSCs. A pivotal phase III-controlled trial using allogenic ADSCs (Alofisel®) demonstrated that prolonged clinical and radiological remission can be obtained in nearly 60% of cases with a good safety profile. Future studies should be conducted for a better knowledge of the local effect of ADSCs as well as for a standardization in terms of the number of injections and associated procedures. 相似文献