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1.
The receptor-binding factor (RBF) for the avian oviduct progesterone (Pg) receptor (PR) has previously been shown to be a unique 10-kDa nuclear matrix protein that generates high affinity PR-binding sites on avian DNA. This paper describes the use of Southwestern blot and DNA gel shift analyses with RBF protein to identify a minimal 54-base pair RBF-binding element in the matrix-associated region (MAR) of the Pg-regulated c-myc gene promoter. This element contains a 5'-GC-rich domain and a 3'-AT-rich domain, the latter of which has a homopurine/homopyrimidine structure. The gel shift assays required the generation of an RBF-maltose fusion protein (RBF-MBP), which specifically binds this element and is supershifted when the anti-RBF polyclonal antibody is added. Computer analysis of the full-length amino acid sequence for RBF predicts a DNA-binding motif involving a beta-sheet structure at the N-terminal domain. Southern blot analyses using nuclear matrix DNA suggests that there are dual MAR sites in the c-myc promoter, which flank an intervening domain containing the RBF element. The co-transfection of this MAR sequence, containing the RBF element and cloned into a luciferase reporter vector, together with an RBF expression vector construct, into steroid treated human MCF-7 cells, results in a decrease of the c-myc promoter activity relative to control transfections containing only the parent vector of the RBF expression construct. These data suggest that a unique chromatin/nuclear matrix structure, composed of the RBF-DNA element complex which is flanked by nuclear matrix attachment sites, serves to bind the PR and repress the c-myc promoter.  相似文献   
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This article examines the psychological impact of participating in sigmoidoscopy screening for colorectal cancer prevention. The 1st study examined psychological well-being at 3 months, in relation to screening outcome, in 4,153 individuals. The 2nd study used longitudinal data to examine changes in psychological functioning from before to after screening in relation both to screening outcome and baseline indicators of vulnerability. There were few psychological differences between those who had received negative results or had polyps detected. These findings were confirmed in the longitudinal study, which also found no evidence for vulnerability to adverse effects among those who were initially most anxious or who perceived their risk of cancer to be higher. The longitudinal data suggested that screening might produce transient positive effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The development of three new content-homogeneous subscales for the revised Minnesota Multiphasic Personality Inventory (MMPI-2; J. N. Butcher et al, 1989) Social Introversion (Si) scale designed to replace the K. Serkownek (1975) subscales, which were not included in the revised MMPI, is described. The subscales, termed Shyness/Self-Consciousness, Social Avoidance, and Self/Other Alienation, were developed with data provided by college students (515 men and 797 women). Data analyses with this and the MMPI-2 normative sample demonstrated that the new subscales independently contribute to the assessment of nearly 90% of the variance in the full Si scale, that they display both convergent and divergent validity, and that these attributes generalize beyond the sample with which they were developed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Metabolic FLIM (fluorescence lifetime imaging) is used to image bioenergetic status in cells and tissue. Whereas an attribution of the fluorescence lifetime of coenzymes as an indicator for cell metabolism is mainly accepted, it is debated whether this is valid for the redox state of cells. In this regard, an innovative algorithm using the lifetime characteristics of nicotinamide adenine dinucleotide (phosphate) (NAD(P)H) and flavin adenine dinucleotide (FAD) to calculate the fluorescence lifetime induced redox ratio (FLIRR) has been reported so far. We extended the FLIRR approach and present new results, which includes FLIM data of the various enzymes, such as NAD(P)H, FAD, as well as flavin mononucleotide (FMN). Our algorithm uses a two-exponential fitting procedure for the NAD(P)H autofluorescence and a three-exponential fit of the flavin signal. By extending the FLIRR approach, we introduced FLIRR1 as protein-bound NAD(P)H related to protein-bound FAD, FLIRR2 as protein-bound NAD(P)H related to free (unbound) FAD and FLIRR3 as protein-bound NAD(P)H related to protein-bound FMN. We compared the significance of extended FLIRR to the metabolic index, defined as the ratio of protein-bound NAD(P)H to free NAD(P)H. The statistically significant difference for tumor and normal cells was found to be highest for FLIRR1.  相似文献   
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This paper is devoted to developing a novel approach to deal with constrained continuous‐time nonlinear systems in the form of Takagi‐Sugeno fuzzy models. Here, the disturbed systems are subject to both input and state constraints. The one‐step design method is used to simultaneously synthesize the dynamic output feedback controller and its anti‐windup strategy. A parameter‐dependent version of the generalized sector condition is used together with Lyapunov stability theory to derive linear matrix inequality design conditions. Based on this result and for different design specifications, the synthesis of an anti‐windup based dynamic output feedback controller is expressed on the form of convex optimization problems. A physically motivated example is given to illustrate the effectiveness of the proposed method.  相似文献   
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Nowadays, micro components have to fulfill rising optical requirements for different scientific and industrial fields like astronomy, medicine or multimedia. For this purpose, advanced miniaturized chip-cameras are produced for the microsystems engineering market. The assembly and joining technologies play a very important role in the production of these micro components. Several challenges are associated with the joining of chip-cameras. In this study, the application of the soldering technology has been considered in order to face these challenges. Two joining technologies have been investigated: active soldering and transient liquid phase (TLP) bonding. Both soldering processes have shown a big potential for hybrid microsystems joining in previous studies. For both processes, soldering alloys and parameters have been conceived in order to fulfill the joining requirements of the micro camera components. For instance, the joining temperature represents a major challenge because the chip-camera consists of a plastic material, polymethyl methacrylate (PMMA). Therefore, particular attention has been directed to the soldering as well as to the coating temperature. The experimental investigations concerning the solders application through physical vapor deposition (PVD) have been supported by finite element method (FEM) simulations. The analysis of  the temperature distribution in the micro components during the coating process was the focus of  the calculations. Possible undesirable local overheated areas of the chip-camera components can be detected through simulation.
Tatyana KashkoEmail:
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Magnetic Resonance Materials in Physics, Biology and Medicine - Signal intensity normalization is necessary to reduce heterogeneity in T2-weighted (T2W) magnetic resonance imaging (MRI) for...  相似文献   
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