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91.
The skin is the largest organ in the human body, comprising the main barrier against the environment. When the skin loses its integrity, it is critical to replace it to prevent water loss and the proliferation of opportunistic infections. For more than 40 years, tissue-engineered skin grafts have been based on the in vitro culture of keratinocytes over different scaffolds, requiring between 3 to 4 weeks of tissue culture before being used clinically. In this study, we describe the development of a polymerizable skin hydrogel consisting of keratinocytes and fibroblast entrapped within a fibrin scaffold. We histologically characterized the construct and evaluated its use on an in vivo wound healing model of skin damage. Our results indicate that the proposed methodology can be used to effectively regenerate skin wounds, avoiding the secondary in vitro culture steps and thus, shortening the time needed until transplantation in comparison with other bilayer skin models. This is achievable due to the instant polymerization of the keratinocytes and fibroblast combination that allows a direct application on the wound. We suggest that the polymerizable skin hydrogel is an inexpensive, easy and rapid treatment that could be transferred into clinical practice in order to improve the treatment of skin wounds.  相似文献   
92.
Effect of organic production system on broiler carcass and meat quality   总被引:5,自引:0,他引:5  
The effect of organic production on broiler carcass and meat quality was assessed. Two hundred and fifty Ross male chickens were assigned to two different systems of production: conventional, housing in an indoor pen (0.12 m(2)/bird); organic, housing in an indoor pen (0.12 m(2)/bird) with access to a grass paddock (4 m(2)/bird). At 56 and 81 days of age, 20 chickens per group were slaughtered to evaluate carcass traits and the characteristics of breast and drumstick muscles (m. pectoralis major and m. peroneus longus). The organic chickens had carcasses with a higher breast and drumstick percentages and lower levels of abdominal fat. The muscles had lower pHu and water holding capacity. Instead cooking loss, lightness values, shear values, Fe, polyunsaturated fatty acids of n-3 series and TBA-RS were higher. The sensory quality of the breast muscle was better. Organic production system seems to be a good alternative method, due to better welfare conditions and good quality of the carcass and meat. A negative aspect was the higher level of TBA-RS in the muscles, probably due to greater physical activity.  相似文献   
93.
Objective: To use multitrait analysis to determine the measurement structure of the Caregiver Empowerment Scale (CES). Participants: An American sample of 87 adult primary family caregivers of persons with traumatic brain injury (TBI). Results: A four-factor structure was identified including factor 1 (Advocacy Self-Efficacy), factor 2 (Community Self-Efficacy), factor 3 (Caregiver Self-Efficacy), and factor 4 (Personal Self-Efficacy). Conclusions: The CES provides clinicians and researchers a means to assess self-perceived coping abilities of family caregivers of persons with TBI. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
94.
Objective: The authors conducted a meta-analysis of empirical studies investigating associations between indices of posttraumatic stress disorder (PTSD) and intimate relationship problems to empirically synthesize this literature. Method: A literature search using PsycINFO, Medline, Published International Literature on Traumatic Stress (PILOTS), and Dissertation Abstracts was performed. The authors identified 31 studies meeting inclusion criteria. Results: True score correlations (ρ) revealed medium-sized associations between PTSD and intimate relationship discord (ρ = .38, N = 7,973, K = 21), intimate relationship physical aggression perpetration (ρ = .42, N = 4,630, K = 19), and intimate relationship psychological aggression perpetration (ρ = .36, N = 1,501, K = 10). The strength of the association between PTSD and relationship discord was higher in military (vs. civilian) samples, and when the study was conducted in the United States (vs. other country), and the study represented a doctoral dissertation (vs. published article). The strength of the association between PTSD and physical aggression was higher in military (vs. civilian) samples, males (vs. females), community (vs. clinical) samples, studies examining PTSD symptom severity (vs. diagnosis), when the physical aggression measure focused exclusively on severe violence (vs. a more inclusive measure), and the study was published (vs. dissertation). For the PTSD–psychological aggression association, 98% of the variance was accounted for by methodological artifacts such as sampling and measurement error; consequently, no moderators were examined in this relationship. Conclusions: Findings highlight a need for the examination of models explaining the relationship difficulties associated with PTSD symptomatology and interventions designed to treat problems in both areas. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
95.
Although several brief instruments are available for the emotional intelligence (EI) construct, their conceptual coverage tends to be quite limited. One notable exception is the short form of the Emotional Quotient Inventory (EQ-i:S), which measures multiple EI dimensions in addition to a global EI index. Despite the unique advantage offered by the inventory, psychometric properties of the EQ-i:S scores have not yet been systematically evaluated. Such an evaluation was the main goal of the present investigation. Using data from 2,508 undergraduates, the authors conducted 2 studies involving factor structure, internal reliability, 6-month temporal stability, and construct validity of the EQ-i:S responses, both for the total EQ scale and for each constituent dimension. The results supported the multidimensional measurement structure of the EQ-i:S, with each dimension producing internally consistent, temporally stable, and theoretically meaningful responses. Scores on the EQ-i:S were associated more strongly with performance on an ability test of EI and with a conceptually similar construct of alexithymia than with the broader dimensions of basic personality and explained nontrivial amounts of incremental variance in the criterion symptoms of attention deficit/hyperactivity disorder. Moreover, scores on each EQ-i:S dimension exhibited unique patterns of associations with the validation variables. The discussion highlights the advantages of the multidimensional approach in the assessment and study of EI. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
96.
There is growing evidence of heterogeneity among responses to bitter stimuli at the peripheral, central and behavioral levels. For instance, the glossopharyngeal (GL) nerve and neurons receiving its projections are more responsive to bitter stimuli than the chorda tympani (CT) nerve, and this is particularly true for some bitter stimuli like PROP & cycloheximide that stimulate the GL to a far greater extent. Given this information, we hypothesized that cutting the GL would have a greater effect on behavioral avoidance of cycloheximide and PROP than quinine and denatonium, which also stimulate the CT, albeit to a lesser degree than salts and acids. Forty male SD rats were divided into four surgery groups: bilateral GL transection (GLX), chorda tympani transection (CTX), SHAM surgery, and combined transection (CTX + GLX). Postsurgical avoidance functions were generated for the four bitter stimuli using a brief-access test. GLX significantly compromised avoidance compared to both CTX and SHAM groups for all stimuli (p  相似文献   
97.
This paper introduces readers to the concepts of implementation science, implementation theory, and implementation frameworks and models. A wide range of models has been published in the literature related to implementation. The paper will present an overview of the Consolidated Framework for Implementation Research (CFIR), which is a comprehensive typology that unifies and consolidates the array of constructs that influence implementation from the perspective of these models. The CFIR is then used to evaluate implementation models used in studies of substance use disorder (SUD) treatments. Implementation research is scarce, with few prospective studies of theory-driven implementation. We assert that future research in SUD needs to meet three overarching objectives to promote wider implementation of evidence-based practices: (a) differentiation of core versus adaptable components of evidence-based interventions need; (b) development of methods to design implementation strategies, effectively adapted to the broad context; and (c) design and testing of predictive models to assess likelihood of effective implementation and prospects for sustainability while taking into account salient contextual factors. A recommended strategy for accomplishing these objectives is described. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
98.
Today's rapid rate of technology change introduces both opportunities and challenges for psychologists. A Technology and Practice Questionnaire was sent to 1000 psychologists in independent practice, half of whom were contacted by e-mail and the other half by U.S. mail. A total of 237 of the 433 deliverable surveys sent by U.S. mail were returned (54.7% response rate), but only 49 of the 458 deliverable surveys sent by e-mail (12.9% response rate). Respondents were asked to rate the frequency of 51 behaviors in their practice and to indicate whether the behavior is ethical. The results suggest a relatively low rate of technology use among independent practitioners and a high degree of ethical uncertainty regarding the use of various technologies in practice. Implications for training and practice are considered. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
99.
This article presents a new approach for incorporating process-integration tools into life cycle analysis (LCA) for biofuel production. Process synthesis techniques using mass- and energy-integration tools are employed to generate various scenarios for reducing mass and energy consumption in the process. The global implications of these changes and the associated trade-offs are assessed using the LCA tool: GREET. The developed approach enables the consideration of several levels of process integration while tracking the process economics and the reduction of the net greenhouse gas emissions. Several cases of biofuels with different processing technologies have been considered in this study, and the results show that when the process-integration tools are effectively utilized and combined with LCA, better insights are obtained and the net greenhouse gas emissions decrease drastically for different biofuels.  相似文献   
100.
The mechanical properties of cast aluminum alloys can be affected by the delay in time involved between the stages of rapid cooling after solubilization (quenching) and aging. This effect was studied on samples from three different Al-Si alloys that were cast with a wide range of microstructures. It was found that the parameter that exerts the highest influence on the mechanical properties is the degree of microstructural refining, which is referred to dendrite arm spacing, as a finer structure enhances the strength and ductility. It was found that the yield strength and total elongation, and to a lesser extend the ultimate tensile strength, are affected by the delay in time. The material that was treated to the peak-aged condition was found to be more susceptible to the reduction in mechanical properties with the increase in the delay in time.  相似文献   
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