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Wojciech Szczęsny Magdalena Kuligowska-Prusińska Stanisław Dąbrowiecki Jakub Szmytkowski Adrian Reśliński Maciej Słupski 《Journal of Zhejiang University. Science. B》2018,19(1):65-70
Purpose
Metalloproteinases are a key component of the pathogenesis of abdominal hernias. Obesity is considered a risk factor in herniogenesis and hernia recurrence. The aim of this study was to evaluate the serum concentrations of metalloproteinase-2 (MMP-2), MMP-9, MMP-13, and adiponectin in morbidly obese and nonoverweight controls.Materials and methods
The participants were recruited from among patients undergoing bariatric and non-bariatric surgery and divided into two groups: I (body mass index (BMI)≥35 kg/m2, n=40) and II (BMI<25 kg/m2, n=30). Serum concentrations of MMP-2, MMP-9, MMP-13, and adiponectin were measured using enzyme-linked immunosorbent assay (ELISA).Results
A statistically significant difference between groups was observed for MMP-2 concentration. The median MMP-9 concentration was higher in the obese group, but the difference was not statistically significant. Median MMP-13 concentrations did not differ between groups. Serum adiponectin concentration was insignificantly higher in the non-obese group.Conclusions
The elevated serum MMP-2 and MMP-9 concentrations in obese individuals may be related to the higher incidence of incisional hernias in this population.13.
Mapping the knowledge structure exhibited by a cohort of students based on their understanding of how a galvanic cell produces energy 
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下载免费PDF全文 This study evaluates the use of an open‐ended question to determine students' knowledge structure on the topic of galvanic cells. The open‐ended question was developed and administered to 163 Grade 10 students who had earlier completed a course on electrochemistry. Students' responses were marked as well as coded on the basis of the fields identified from their responses. This was then evaluated statistically to determine the collective knowledge structure of the sample of students. The knowledge structure thus mapped contains both canonical concepts and alternative conceptions (ACs). An important finding emerging from this study is that instructors need to focus student's attention on the dynamic processes involving electrons and ions during the operation of galvanic cells. In order for students to fully understand how a galvanic cell operates, they need to see the whole picture. There are three critical components that lead to students' understanding of how an oxidation–reduction reaction can generate energy and how a circuit is complete: transfer of electrons during oxidation–reduction half‐reactions, flow of electrons within metals, and migration of ions in solution. Also, we found that it is possible for students to use correct chemistry concepts in an incorrect way by establishing linkages among these in an inappropriate manner. We reiterate that apart from evaluating students' ACs, it is also important to evaluate the links between the concepts and conceptions present in students' knowledge structure so that teaching can be made more effective. 相似文献
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Yvonne O'Brien Sheila Glenn Cliff Cunningham 《International Journal of Disability, Development & Education》1994,41(3):231-243
Seven infants and children with severe, profound and multiple learning difficulties (CA 3 months to 4 years, MA 2 months to 12 months, mean MA 4.5 months) were presented with a contingency situation where they could control the onset of a visually and auditorily attractive toy. In this situation their responding increased and some positive emotional effects were seen. When they were subsequently unable to control stimulation, negative effects were seen on a range of emotional, motivational and self‐stimulation measures. These results suggest that from a mental age level of 2 months children are equipped to detect cause and effect relationships and build up a picture of their world based on expectancies about such relationships; and that violations of these expectancies can lead to negative effects. 相似文献
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In November 2006, a focus group of researchers was assembled at a conference hosted by the Society of Scholarly Publishers in Washington, DC. The panel addressed a series of prepared questions regarding current research practices, perceptions, and preferences, particularly as they applied to scientific and medical publications, in corporate, academic, and medical environments. This article highlights issues and views the panel discussed, with the aim of narrowing the gap of understanding between researchers and publishers. This information will help publishers to develop content and delivery methods that are closely aligned with the needs of researchers. 相似文献
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