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排序方式: 共有413条查询结果,搜索用时 78 毫秒
41.
Immune and Anticancer Responses Elicited by Fully Synthetic Aberrantly Glycosylated MUC1 Tripartite Vaccines Modified by a TLR2 or TLR9 Agonist 下载免费PDF全文
Dr. Abu‐Baker M. Abdel‐Aal Dr. Vani Lakshminarayanan Dr. Pamela Thompson Nitin Supekar Judy M. Bradley Dr. Margreet A. Wolfert Prof. Dr. Peter A. Cohen Prof. Dr. Sandra J. Gendler Prof. Dr. Geert‐Jan Boons 《Chembiochem : a European journal of chemical biology》2014,15(10):1508-1513
The mucin MUC1 is overexpressed and aberrantly glycosylated by many epithelial cancer cells manifested by truncated O‐linked saccharides. Although tumor‐associated MUC1 has generated considerable attention because of its potential for the development of a therapeutic cancer vaccine, it has been difficult to design constructs that consistently induce cytotoxic T‐lymphocytes (CTLs) and ADCC‐mediating antibodies specific for the tumor form of MUC1. We have designed, chemically synthesized, and immunologically examined vaccine candidates each composed of a glycopeptide derived from MUC1, a promiscuous Thelper peptide, and a TLR2 (Pam3CysSK4) or TLR9 (CpG‐ODN 1826) agonist. It was found that the Pam3CysSK4‐containing compound elicits more potent antigenic and cellular immune responses, resulting in a therapeutic effect in a mouse model of mammary cancer. It is thus shown, for the first time, that the nature of an inbuilt adjuvant of a tripartite vaccine can significantly impact the quality of immune responses elicited against a tumor‐associated glycopeptide. The unique adjuvant properties of Pam3CysSK4, which can reduce the suppressive function of regulatory T cells and enhance the cytotoxicity of tumor‐specific CTLs, are likely responsible for the superior properties of the vaccine candidate 1 . 相似文献
42.
Arno J. Van der Vlist Marien H. Vrolijk Geert P.M.R. Dewulf 《Construction Management & Economics》2014,32(6):641-651
The interplay between information and communication technology (ICT) and the competitiveness of construction firms is considered. More specifically, the question is whether firms that invest in information and communication technology have a production cost advantage. The economics literature hypothesizes that ICT brings about a production cost advantage, as ICT brings flexibility and improves the planning, organization and control of work. To test this proposition for the construction industry, a production cost function allowing for the inclusion of ICT is formulated. Using statistical nearest-neighbour matching methods it is possible to identify the effect of ICT on production costs thereby controlling for economic moderators. Data from a sample of Dutch construction firms reveal that those firms that installed ICT capital do have a production cost advantage. The results indicate further that firms need a minimum level of ICT capital to fully benefit from its production cost advantage. 相似文献
43.
Evaluating the effectiveness of a post-license education program for young novice drivers in Belgium
Kris Brijs Ariane Cuenen Tom Brijs Robert A.C. Ruiter Geert Wets 《Accident; analysis and prevention》2014
The disproportionately large number of traffic accidents of young novice drivers highlights the need for an effective driver education program. The Goals for Driving Education (GDE) matrix shows that driver education must target both lower and higher levels of driver competences. Research has indicated that current education programs do not emphasize enough the higher levels, for example awareness and insight. This has raised the importance of insight programs. On the Road (OtR), a Flemish post-license driver education program, is such an insight program that aims to target these higher levels. The program focus is on risky driving behavior like speeding and drink driving. In addition, the program addresses risk detection and risk-related knowledge. The goal of the study was to do an effect evaluation of this insight program at immediate post-test and 2 months follow-up. In addition, the study aimed to generalize the results of this program to comparable programs in order to make usable policy recommendations. A questionnaire based on the Theory of Planned Behavior (TPB) was used in order to measure participants’ safety consciousness of speeding and drink driving. Moreover, we focused on risk detection and risk-related knowledge. Participants (N = 366) were randomly assigned to a baseline—follow-up group or a post-test—follow-up group. 相似文献
44.
Wielinga PR de Heer L de Groot A Hamidjaja RA Bruggeman G Jordan K van Rotterdam BJ 《International journal of food microbiology》2011,150(2-3):122-127
The DNA extraction efficiency from milk, whey, soy, corn gluten meal, wheat powders and heat-treated corn grain that were spiked with Bacillus anthracis and Bacillus thuringiensis spores was determined. Two steps were critical: lysis of the spores and binding of the free DNA to the DNA binding magnetic beads in the presence of the interfering powders. For the guanidine-thiocyanate based Nuclisens lysis buffer from Biomerieux we found that between 15 and 30% of the spores survived the lysis step. As most lysis buffers in DNA/RNA extraction kits are guanidine based it is likely that other lysis buffers will show a similar partial lysis of the Bacillus spores. Our results show that soybean flour and wheat flour inhibited the DNA extraction process strongest, leading to unreliable DNA extractions when using too much of the matrix. For corn gluten meal, heat-treated corn grain and milk powders, DNA extraction efficiencies in the presence of 100mg and 10mg of powder resulted in 70%-95% reduced DNA recoveries. The inhibition was, however, reliable and intermediate compared to the inhibition by soy and wheat. Whey powder had the lowest inhibitory effect on DNA-extraction efficiency and recoveries of 70-100% could be reached when using 10mg of powder. The results show that reducing the amount of matrix leads to better DNA-extraction efficiencies, particularly for strongly inhibiting powders such as soy and wheat. Based on these results, a standard protocol to directly isolate DNA from micro-organisms present in complex matrixes such as food and feed powders was designed. 相似文献
45.
During the last decade many techniques were developed to detect fatigue cracks, and estimate their location and size. Unfortunately, most of the currently available nondestructive testing methods are off-line: the operational (or fatigue) loading and the inspection are considered as two distinct stages. Mostly, the loading should be released before inspection can take place, and sometimes the device under test even has to be disassembled. In this article, an experimental methodology based on ultrasonic surface waves will be developed to continuously inspect a structure during its operation. The proposed method uses spectral information of transmitted surface waves at several working points of the operational load. Simple statistical indicators of the transmitted wave energy during loading are introduced in order to be able to monitor the structural health on-line. As a validation experiment, a propagating fatigue crack in a sinusoidally loaded beam will be considered. In addition, a comparison with an off-line method is made, showing that the on-line method is also much more sensitive. 相似文献
46.
Building and maintaining high quality knowledge based systems is not a trivial task. Decision tables have sometimes been recommended in this process, mainly in verification and validation. In this paper, however, it is shown how decision tables can also be used to generate, and not just to validate, knowledge bases and how the transformation process from decision tables to knowledge bases can be organized. Several options to generate rules or other knowledge representation from decision tables are described and evauluated.
The proposed generation strategy enables the knowledge engineer to concentrate on the acquisition and modelling issues and allows him to isolate the knowledge body from its implementation. The generation process has been implemented for two commercial tools, AionDS and KBMS and has been applied to real world applications. 相似文献
47.
Jurgen Martens Geert Wets Jan Vanthienen Christophe Mues 《Expert systems with applications》1998,15(3-4):375-381
At the present time a large number of AI methods have been developed in the field of pattern classification. In this paper, we will compare the performance of a well-known algorithm in machine learning (C4.5) with a recently proposed algorithm in the fuzzy set community (NEFCLASS). We will compare the algorithms both on the accuracy attained and on the size of the induced rule base. Additionally, we will investigate how the selected algorithms perform after they have been pre-processed by discretization and feature selection. 相似文献
48.
This paper is concerned with the derivation of closed-loop Stackelberg (CLS) solutions of a class of continuous-time two-player nonzero-sum differential games characterized by linear state dynamics and quadratic cost functionals. Explicit conditions are obtained for both the finite and infinite horizon problems under which the CLS solution is a representation of the optimal feedback solution of a related team problem which is defined as the joint minimization of the leader's cost function. First, a specific class of representations is considered which depend linearly on the current and initial values of the state, and then the results are extended to encompass a more general class of linear strategies that also incorporate the whole past trajectory. The conditions obtained all involve solutions of linear matrix equations and are amenable to computational analysis for explicit determination of CLS strategies. 相似文献
49.
Victor G. Mihucz Geert Silversmit Imre Szalóki Björn de Samber Tom Schoonjans Enikő Tatár László Vincze István Virág Jun Yao Gyula Záray 《Food chemistry》2010
Extraction of As, Cd, Cu, Mn, Ni and Ti from two white as well as from one brown rice samples was studied by inductively coupled plasma sector field mass spectrometry (ICP-SF-MS). Samples were subjected to cold and hot water extraction (rice mass to deionised water volume ratio = 1:6, and 1:3, respectively). The discarded liquids were freeze-dried and digested by microwave-assisted digestion. About 50% of the content of the investigated elements could be extracted from the white rice. In case of the brown rice, the boiling water contained As, Cd, Ni and Ti in significant percentages. Elemental distributions in the rice grains determined by synchrotron radiation confocal micro-X-ray fluorescence analysis revealed that a surface layer having a thickness of about 80 μm is the richest region in elements. Ti was detectable only in this so-called skin region. Good correlation was observed for the extraction of As, Mn, Ni and Ti by the above-mentioned two techniques. Thus, in regions affected by heavy metal and other toxic element contamination, those rice dishes would be preferred whose preparation should need abundant amounts of water for washing and cooking, which later should be discarded. 相似文献
50.
Wouter N. Wermink Dmitri Spinu Geert F. Versteeg 《Chemical Engineering Communications》2019,206(4):454-475
The oxidation of ferrous ions in acidic sulfate solutions in the presence of cupric ions at elevated air pressures was investigated in a high-intensity gas–liquid contactor. The study was required for the design of the regeneration steps of the novel Vitrisol® desulphurization process. The effects of the Fe2+ concentration, Cu2+ concentration, Fe3+ concentration, initial H2SO4 concentration, and partial oxygen pressure on the reaction rate were determined at three different temperatures, i.e., T?=?50?°C, 70?°C, and 90?°C. Most of the experiments were determined to be affected by the mass transfer of oxygen, and therefore true intrinsic kinetics could not be fully determined. An increase in Fe2+ and Cu2+ concentrations, as well as the partial pressure of oxygen and temperature, increased the Fe2+ oxidation rate. H2SO4 did not influence the Fe2+ oxidation rate. An increase in Fe3+ concentration decreased the Fe2+ oxidation rate. Although determined from experiments partially affected by mass transfer, a first order of reaction in Fe2+ was observed, fractional orders in both Cu2+ and O2 were measured, a zero order in H2SO4 was determined, and a negative, fractional order in Fe3+ was obtained. The activation energy was estimated to be 31.3?kJ/mol. 相似文献