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991.
992.
To investigate dietary protein level effects on digestive mechanisms, weaned piglets were fed for 45 d with diets containing 20%, 17%, or 14% crude protein (CP) supplemented to meet requirements for essential amino acids. This article describes the influence of dietary protein on gastrointestinal hormones and expression of an array of digestive enzymes in the gastrointestinal tract and pancreas. Results indicated that there were no significant differences in expression of enzymes involved in carbohydrate digestion, except for maltase in the duodenum. In the jejunum, amylase expression in pigs fed 20% CP was much higher than that in pigs fed other diets (P<0.05) and maltase expression in those fed 17% CP was higher than that in other treatments (P<0.05). Although there were no remarkable differences in expression of aminopeptidase in the small intestine or carboxypeptidase in the pancreas (P>0.05), there was a trend towards higher expression of various proteases in pigs fed 17% CP. The duodenal expression of enteropeptidase in diets with 14% and 17% CP was significantly higher than that with 20% CP (P<0.05), but treatment differences did not existed in jejunum (P>0.05). The expression of GPR93 as a nutrient-responsive G protein-coupled receptor in 14% and 17% CP diets was significantly higher than that in 20% CP diet in the small intestine (P<0.05). The expressions of genes for pancreatic enzymes, lipase and elastase, were significantly higher in pigs fed diets with low CP, while similar trends occurred for carboxypeptidase, chymotrypsin and amylase. Conversely, the gastric expressions of pepsinogen A and progastricsin were lower with the 17% CP diet. Differences between treatments were found in the gastric antral contents of cholecystokinin and somatostatin: both increased in pigs fed 17% CP, accompanied by decreased content of motilin, which was also seen in plasma concentrations. These patterns were not reflected in duodenal contents. In general, 17% dietary CP was beneficial to the digestion of nutrient substance in the gastrointestinal tract.  相似文献   
993.
There are child soldiers fighting with government forces and opposition groups in more than 30 countries worldwide. Although studies have been conducted on the impact of war-related trauma on children, very few have focused on those children who do not exhibit trauma-related symptoms after experiencing armed combat. The purpose of this study was to identify and understand some of the mechanisms and resources that resilient children draw upon to overcome the trauma of child soldiering. Six Colombian child soldiers were recruited through purposive sampling techniques to participate in a narrative study focusing on their lived experiences and their personal understanding of how they were able to overcome the effects of war trauma. Six narrative themes were identified and discussed in terms of the literature on trauma and childhood resilience and also related to counselling needs and services.  相似文献   
994.
This study investigated the alleviating effects of hydrogen sulfide (H2S), derived from sodium hydrosulfide (NaHS), on inflammation induced by dextran sulfate sodium (DSS) in both in vivo and in vitro models. We found that NaHS injection markedly decreased rectal bleeding, diarrhea, and histological injury in DSS-challenged mice. NaHS (20 µmol/L) reversed DSS-induced inhibition in cell viability in Caco-2 cells and alleviated pro-inflammation cytokine expression in vivo and in vitro, indicating an anti-inflammatory function for H2S. It was also found that H2S may regulate cytokine expression by inhibiting the nuclear factor-κB (NF-κB) signaling pathway. In conclusion, our results demonstrated that H2S alleviated DSS-induced inflammation in vivo and in vitro and that the signal mechanism might be associated with the NF-κB signaling pathway.  相似文献   
995.
A five-dimensional framework for authentic assessment   总被引:1,自引:2,他引:1  
Authenticity is an important element of new modes of assessment. The problem is that what authentic assessment really is, is unspecified. In this article, we first review the literature on authenticity of assessments, along with a five-dimensional framework for designing authentic assessments with professional practice as the starting point. Then, we present the results of a qualitative study to determine if the framework is complete, and what the relative importance of the five dimensions is in the perceptions of students and teachers of a vocational college for nursing. We discuss implications for the framework, along with important issues that need to be considered when designing authentic assessments.  相似文献   
996.
The labour market rewards for a number of required human capital competences are analysed using a sample of young European higher education graduates. Factor analysis is applied to classify competences by jobs into eight orthogonal groups, namely participative, methodological, specialised, organisational, applying rules, physical, generic and socio-emotional competences. Estimates for the total rewards for competences are obtained through conventional wage regression, whereas estimates of the total rewards are derived in terms of job satisfaction through ordered logit regression. Explanatory variables include personal characteristics, job attributes, occupational titles, fields of study, type of higher education institution and country dummies. Results on wage rewards show that jobs with higher requirements of participativeand methodological competencesare best paid; conversely, jobs with higher requirements of organisational, applying-rulesand physical competencesare worse paid. Results on total rewards suggest that jobs with higher requirements of competences increase graduates' satisfaction, the only exception being applying-rules competences.  相似文献   
997.
A survey was conducted to determine whether mycotoxins were present in the foods consumed by red-crowned cranes (Grus japonensis) in the Yancheng Biosphere Reserve, China. Collected in the reserve’s core, buffer, and experimental zones during overwintering periods of 2013 to 2015, a total of 113 food samples were analyzed for aflatoxin B1, deoxynivalenol, zearalenone, T-2 toxin, and ochratoxin A using high performance liquid chromatography (HPLC). The contamination incidences vary among different zones and the mycotoxins levels of different food samples also presented disparity. Average mycotoxin concentration from rice grain was greater than that from other food types. Among mycotoxin-positive samples, 59.3% were simultaneously contaminated with more than one toxin. This study demonstrated for the first time that red-crowned cranes were exposed to mycotoxins in the Yancheng Biosphere Reserve and suggested that artificial wetlands could not be considered good habitats for the birds in this reserve, especially rice fields.  相似文献   
998.
Nonlinear solution of reinforced concrete structures, particularly complete load-deflection response, requires tracing of the equilibrium path and proper treatment of the limit and bifurcation points. In this regard, ordinary solution techniques lead to instability near the limit points and also have problems in case of snap-through and snap-back. Thus they fail to predict the complete load-displacement response. The arc-length method serves the purpose well in principle, Received wide acceptance in finite element analysis, and has been used extensively. However modifications to the basic idea are vital to meet the particular needs of the analysis. This paper reviews some of the recent developments of the method in the last two decades, with particular emphasis on nonlinear finite element analysis of reinforced concrete structures.  相似文献   
999.
1000.
In view of the challenges facing universities in our days and in accordance with the guidelines of the EHEA, the present article presents the results of a project which aims to unite the use of blogs and a competency approach. Specifically, the project is structured around two basic, complementary aims: 1. The design and implementation of a teaching innovation project which through the use of blogs promotes the development of certain professional competencies and 2. To assess the experiences and comments of students regarding the use of blogs in a university context, in order to appraise how students assess the use of this new learning tool. To achieve the latter aim, we used a methodology that combines a questionnaire with content analysis, using a sample of 82 subjects. The article shows that university students consider the blog as a tool that enables the acquisition of professional competencies, boosts the teaching-learning process, and foments the development of reflection. Based on these results, several proposals are made concerning the use of blogs, including activities related to reflection, provision of training-focused feedback, and the use of labels as an exercise of metareflection, amongst others.  相似文献   
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