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991.
Empirically-supported treatments for alcohol dependence exist, yet understanding of influences contributing to the intended behavior change is limited. The current study, a secondary analysis of the recent multisite COMBINE trial (The COMBINE Study Research Group, 2003), tested a mediational model wherein change in client self-efficacy for abstinence was examined as a potential mediator of associations between client report of the therapeutic bond and one-year outcomes of drinking frequency, drinking consequences, and psychiatric functioning. For analyses, the 1383 COMBINE trial participants were grouped as follows: 1) those receiving study medications (naltrexone, acamprosate, naltrexone + acamprosate, placebo) and enrolled in medication management (MM) only (n = 607), 2) those receiving study medications/MM and also enrolled in a combination behavioral intervention (CBI) as well (n = 619), and 3) those enrolled in CBI only (n = 157). Mediation analyses using the product-of-coefficients approach indicated self-efficacy change during treatment significantly mediated associations between the therapeutic bond with the CBI therapist and each of the three one-year outcomes among those exclusively receiving CBI, but failed to do so among those receiving pills/MM (with or without CBI). Effect sizes were small, but indicated that variance in bond-outcome associations was partially mediated by self-efficacy change for trial participants. Findings advance understanding of proximal client change processes during delivery of treatments for alcohol dependence. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
992.
Mast cells (MCs) and macrophages (Mϕs) are innate immune cells that differentiate from early common myeloid precursors and reside in all body tissues. MCs have a unique capacity to neutralize/degrade toxic proteins, and they are hypothesized as being able to adopt two alternative polarization profiles, similar to Mϕs, with distinct or even opposite roles. Mϕs are very plastic phagocytic cells that are devoted to the elimination of senescent/anomalous endogenous entities (to maintain tissue homeostasis), and to the recognition and elimination of exogenous threats. They can adopt several functional phenotypes in response to microenvironmental cues, whose extreme profiles are the inflammatory/killing phenotype (M1) and the anti-inflammatory/healing phenotype (M2). The concomitant and abundant presence of these two cell types and the partial overlap of their defensive and homeostatic functions leads to the hypothesis that their crosstalk is necessary for the optimal coordination of their functions, both under physiological and pathological conditions. This review will examine the relationship between MCs and Mϕs in some situations of homeostatic regulation (menstrual cycle, embryo implantation), and in some inflammatory conditions in the same organs (endometriosis, preeclampsia), in order to appreciate the importance of their cross-regulation.  相似文献   
993.
In this paper we initiate an investigation about security problems which occur when exploiting a Linda-like data driven coordination model in an open environment. In this scenario, there is no guarantee that all the agents accessing the shared tuple space are trusted. Starting from the analysis of the few proposals already available in the literature, we present a novel coordination model which provides mechanisms to manage tuple access control. The first mechanism supports logical partitions of the shared repository: in this way we can restrict the access to tuples inside a partition, simply by limiting the access to the partition itself. The second mechanism consists of adding to the tuples some extra information which exploit asymmetric cryptography in order, e.g., to authenticate the producer of a tuple or to identify its reader/consumer. Finally, we support the possibility to define access control policies based on the kind of operations an agent performs on a tuple, thus discriminating between (destructive) input and (non-destructive) read operations.  相似文献   
994.
Mitochondrial respiratory chain (MRC) disorders are a complex group of diseases whose diagnosis requires a multidisciplinary approach in which the biochemical investigations play an important role. Initial investigations include metabolite analysis in both blood and urine and the measurement of lactate, pyruvate and amino acid levels, as well as urine organic acids. Recently, hormone-like cytokines, such as fibroblast growth factor-21 (FGF-21), have also been used as a means of assessing evidence of MRC dysfunction, although work is still required to confirm their diagnostic utility and reliability. The assessment of evidence of oxidative stress may also be an important parameter to consider in the diagnosis of MRC function in view of its association with mitochondrial dysfunction. At present, due to the lack of reliable biomarkers available for assessing evidence of MRC dysfunction, the spectrophotometric determination of MRC enzyme activities in skeletal muscle or tissue from the disease-presenting organ is considered the ‘Gold Standard’ biochemical method to provide evidence of MRC dysfunction. The purpose of this review is to outline a number of biochemical methods that may provide diagnostic evidence of MRC dysfunction in patients.  相似文献   
995.
Bifidobacterium are prominent gut commensals that produce the short-chain fatty acid (SCFA) acetate, and they are often used as probiotics. Connections between the gut and the lung, termed the gut–lung axis, are regulated by the microbiome. The gut–lung axis is increasingly implicated in cigarette smoke-induced diseases, and cigarette smoke exposure has been associated with depletion of Bifidobacterium species. In this study, we assessed the impact of acetate-producing Bifidobacterium longum subsp. longum (WT) and a mutant strain with an impaired acetate production capacity (MUT) on cigarette smoke-induced inflammation. The mice were treated with WT or MUT B. longum subsp. longum and exposed to cigarette smoke for 8 weeks before assessments of lung inflammation, lung tissue gene expression and cecal SCFAs were performed. Both strains of B. longum subsp. longum reduced lung inflammation, inflammatory cytokine expression and adhesion factor expression and alleviated cigarette smoke-induced depletion in caecum butyrate. Thus, the probiotic administration of B. longum subsp. longum, irrespective of its acetate-producing capacity, alleviated cigarette smoke-induced inflammation and the depletion of cecal butyrate levels.  相似文献   
996.
Killian’s (antrochoanal) polyp is a unilateral nasal polypoid lesion of the maxillary sinus especially affecting children and young adults with unilateral nasal obstruction, pus discharge, and headache. Although its etiology is unclear, chronic inflammation, autoreactivity, allergies, and viral infections are implicated in its formation and development, causing nasal tissue remodeling. In this context, we isolated and cultured mesenchymal stem cells from surgical biopsies of three patients with Killian nasal polyp (KNP-MSCs) while healthy nasal tissue (HNT-MSCs) was used as control. Our results demonstrated that KNP-MSCs exhibited reduced cell proliferation compared to HNT-MSCs, and migrated less than the control, showing a partial epithelial phenotype with low mRNA levels of I-CAM and a significant increase of E-cad. Subsequently, both MSCs were induced to osteoblastic or adipocyte differentiation for up to 20 days. KNP-MSCs underwent to differentiate into osteoblasts but exhibited reduced ALP activity and calcium deposits and low mRNA levels of osteogenesis-associated genes compared to osteogenic induced-HNT-MSCs. Conversely, KNP-MSCs and HNT-MSCs have shown the same adipogenic differentiation potential, with a similar lipid droplet amount, adipocyte gene expression, and triacylglycerols content. Taken together, these results first demonstrated the cellular and molecular characterization of MSCs derived from the Killian nasal polyp.  相似文献   
997.
Glycosylation, which consists of the enzymatic addition of sugars to proteins and lipids, is one of the most important post-co-synthetic modifications of these molecules, profoundly affecting their activity. Although the presence of carbohydrate chains is crucial for fine-tuning the interactions between cells and molecules, glycosylation is an intrinsically stochastic process regulated by the relative abundance of biosynthetic (glycosyltransferases) and catabolic (glycosidases) enzymes, as well as sugar carriers and other molecules. Non-coding RNAs, which include microRNAs, long non-coding RNAs and circRNAs, establish a complex network of reciprocally interacting molecules whose final goal is the regulation of mRNA expression. Likewise, these interactions are stochastically regulated by ncRNA abundance. Thus, while protein sequence is deterministically dictated by the DNA/RNA/protein axis, protein abundance and activity are regulated by two stochastic processes acting, respectively, before and after the biosynthesis of the protein axis. Consequently, the worlds of glycosylation and ncRNA are closely interconnected and mutually interacting. In this paper, we will extensively review the many faces of the ncRNA–glycosylation interplay in cancer and other physio-pathological conditions.  相似文献   
998.
Automatic modeling of virtual humans and body clothing   总被引:2,自引:0,他引:2       下载免费PDF全文
Highly realistic virtual human models are rapidly becoming commonplace in computer graphics. These models, often represented by complex shape and requiring labor-intensive process, challenge the problem of automatic modeling. The problem and solutions to automatic modeling of animatable virtual humans are studied. Methods for capturing the shape of real people, parameterization techniques for modeling static shape (the variety of human body shapes) and dynamic shape (how the body shape changes as it moves) of virtual humans are classified, summarized and compared. Finally, methods for clothed virtual humans are reviewed.  相似文献   
999.
1000.
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