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排序方式: 共有4931条查询结果,搜索用时 15 毫秒
31.
Muhammad Irfan Irshad Ahmad Shazia Shukrullah Humaira Hussain Muhammad Atif Stanislaw Legutko Jana Petru Michal Hatala Muhammad Yasin Naz Saifur Rahman 《Materials》2022,15(13)
The development of cost-effective co-catalysts of high photocatalytic activity and recyclability is still a challenge in the energy transformation domain. In this study, 0D/2D Schottky heterojunctions, consisting of 0D ZnO and 2D Ti3C2, were successfully synthesized by the electrostatic self-assembling of ZnO nanoparticles on Ti3C2 nanosheets. In constructing these heterojunctions, Ti3C2 nanosheets acted as a co-catalyst for enhancing the transfer of excitons and their separation to support the photocatalytic response of ZnO. The as-prepared ZnO/Ti3C2 composites demonstrate an abbreviated charge transit channel, a huge interfacial contact area and the interfacial electrons’ transport potential. The extended optical response and large reactive area of the ZnO/Ti3C2 composite promoted the formation of excitons and reactive sites on the photocatalyst’s surface. The ZnO/Ti3C2 Schottky heterojunction showed significantly high photocatalytic activity for hydrogen production from a water–ethanol solution under the light illumination in the visible region. The hydrogen evolution overoptimized the ZnO/Ti3C2 composition with 30 wt.% of Ti3C2, which was eight times higher than the pristine ZnO. These findings can be helpful in developing 0D/2D heterojunction systems for photocatalytic applications by utilizing Ti3C2 as a low-cost co-catalyst. 相似文献
32.
Igor Koloniuk Alena Matyov Sra Brzdov Jana Vesel Jaroslava Pibylov Jana Frnov Santiago F. Elena 《Viruses》2022,14(7)
Advances in high-throughput sequencing methods have boosted the discovery of multistrain viral infections in diverse plant systems. This phenomenon appears to be pervasive for certain viral species. However, our knowledge of the transmission aspects leading to the establishment of such mixed infections is limited. Recently, we reported a mixed infection of a single strawberry plant with strawberry mottle virus (SMoV), strawberry crinkle virus (SCV) and strawberry virus 1 (StrV-1). While SCV and StrV-1 are represented by two and three molecular variants, respectively, SmoV has three different RNA1 and RNA2 segments. In this study, we focus on virus acquisition by individual adult aphids of the Aphis gossypii, Aphis forbesi and Chaetosiphon fragaefolii species. Single-aphid transmission trials are performed under experimental conditions. Both different viruses and individual virus strains show varying performances in single aphid acquisition. The obtained data suggests that numerous individual transmission events lead to the establishment of multistrain infections. These data will be important for the development of epidemiological models in plant virology. 相似文献
33.
Zdenek Belohlav Lucie Brenkova Jana Kalcikova Jiri Hanika Petr Durdil Vaclav Tomasek 《Pharmaceutical development and technology》2013,18(4):345-352
A fuzzy model has been developed for the optimization of high-shear wet granulation wetting on a plant scale depending on the characteristics of pharmaceutical active substance particles. The model optimized on the basis of experimental data involves a set of rules obtained from expert knowledge and full-scale process data. The skewness coefficient of particle size distribution and the tapped density of the granulated mixture were chosen as the model input variables. The output of the fuzzy ruled system is the optimal quantity of wetting liquid. In comparison to manufacturing practice, a very strong sensitivity of the optimal quantity of the added wetting liquid to the size and shape of the active substance particles has been identified by fuzzy modeling. 相似文献
34.
OBJECTIVES: Evaluation of the complications rate, as well as pregnancy outcome, in women who underwent early and mid-trimester amniocentesis. MATERIAL AND METHODS: The study was conducted among 454 patients, including 162 women after the procedure performed before 15 gestational week and 292 patients who underwent classic amniocentesis. All patients were hospitalized in Division of Reproduction of University of Medical Sciences in Poznan between 1999 and 2005. The analysis, based both on clinical observations and questionnaire sent to patients, concerned especially the frequency of following complications: miscarriage, premature rupture of membranes and club foot in newborns. RESULTS: Total pregnancy loss rate due to amniocentesis amounted to 1.2% and 0.3% in early and mid-trimester amniocentesis, respectively, not reaching statistical significance. The frequency of club foot in newborns of mothers who underwent amniocentesis did not differ significantly between the groups, although it was four times higher in early amniocentesis group than in patients in whom mid-trimester amniocentesis had been performed. CONCLUSIONS: The safety of early amniocentesis is comparable with safety of mid-trimester amniocentesis. 相似文献
35.
Jana Ihlow Sophia Gross Leonie Busack Anne Flrcken Julia Jesse Michaela Schwarz Nina Rosa Neuendorff Ann-Christin von Brünneck Ioannis Anagnostopoulos Seval Türkmen Igor Wolfgang Blau Thomas Burmeister David Horst Lars Bullinger Jrg Westermann 《Haematologica》2022,107(8):1773
In acute myeloid leukemia, there is an ongoing debate on the prognostic value of the early bone marrow assessment in patients receiving intensive therapy. In this retrospective study, we analyzed the prognostic impact of the early response in 1,008 patients with newly diagnosed acute myeloid leukemia, who were treated at our institution with intensive chemotherapy followed by consolidation chemotherapy and/or allogeneic hematopoietic stem cell transplantation (HSCT). We found that early blast persistence has an independent negative prognostic impact on overall survival, event-free survival and relapse-free survival. This negative prognostic impact may only be overcome in patients showing at least a partial remission at the early bone marrow assessment and who subsequently achieve blast clearance by additional induction chemotherapy prior to consolidation therapy with allogeneic HSCT. In accordance, we propose that the time slope of remission is an additional leukemia-related dynamic parameter that reflects chemosensitivity and thus may inform post-induction therapy decision-making. In addition to patient-related factors, European LeukemiaNet risk group, measurable residual disease monitoring and donor availability, this may particularly apply to European LeukemiaNet intermediate-risk patients, for whom a decision between consolidation chemotherapy and allogeneic HSCT remains challenging in many cases. 相似文献
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Two inverse methods using dipole models for noninvasive assessment of local repolarization changes were investigated and compared in the simulation study. Lesions with changed repolarization were modeled by shortening of the action potential durations in ventricular regions typically influenced by occlusion of coronary arteries. Corresponding body surface potentials were computed using a multiple dipole model of the cardiac generator and an inhomogeneous torso model. Position of each lesion was then estimated by an inverse solution to a single dipole and to a group of five neighbouring dipoles. For both methods the lesion localization error was evaluated and its dependence on the lesion size and the noise in input data was studied. When no noise was present in the input data, the use of the inverse method to a group of dipoles instead of a single dipole resulted in an unsubstantial reduction of the mean localization error of small lesions from 0.6 to 0.5 cm. For medium and especially for large lesions the mean localization errors decreased significantly from 1.1 to 0.6 cm and from 2.3 to 1.0 cm, respectively. The inverse solution to a group of five dipoles was more sensitive to noise. However, for large lesions it still gave better results than the solution to a single dipole if the signal to noise ratio was higher than 30 dB. 相似文献
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40.
Molecular dissection of Meis1 reveals 2 domains required for leukemia induction and a key role for Hoxa gene activation 下载免费PDF全文
Mamo A Krosl J Kroon E Bijl J Thompson A Mayotte N Girard S Bisaillon R Beslu N Featherstone M Sauvageau G 《Blood》2006,108(2):622-629
The Hoxa9 and Meis1 genes represent important oncogenic collaborators activated in a significant proportion of human leukemias with genetic alterations in the MLL gene. In this study, we show that the transforming property of Meis1 is modulated by 3 conserved domains, namely the Pbx interaction motif (PIM), the homeodomain, and the C-terminal region recently described to possess transactivating properties. Meis1 and Pbx1 interaction domain-swapping mutants are dysfunctional separately, but restore the full oncogenic activity of Meis1 when cotransduced in primary cells engineered to overexpress Hoxa9, thus implying a modular nature for PIM in Meis1-accelerated transformation. Moreover, we show that the transactivating domain of VP16 can restore, and even enhance, the oncogenic potential of the Meis1 mutant lacking the C-terminal 49 amino acids. In contrast to Meis1, the fusion VP16-Meis1 is spontaneously oncogenic, and all leukemias harbor genetic activation of endogenous Hoxa9 and/or Hoxa7, suggesting that Hoxa gene activation represents a key event required for the oncogenic activity of VP16-Meis1. 相似文献