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Children may have difficulty with schoolwork because of grief over the death of an important person in their lives. School nurses provide support to these children. This pilot study consisted of a Web-based survey completed by 6 school nurses in a 3-county area in Washington state. The purpose of this pilot study was to assess the need for additional support for bereaved children and the extent to which school nurses meet the needs of these students. Results indicated that many school nurses have large caseloads that preclude spending as much time with bereaved students as the nurses feel is necessary. Bereaved students exhibit a wide variety of grief symptoms that may interfere with learning. In addition, rural areas do not have adequate community bereavement resources that nurses can use to refer students who need help beyond that offered at school. Nurses must be more active in supporting students within the school setting despite limited resources.  相似文献   
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The biophysical mechanisms that drive and regulate cardiac looping are not well understood, but mechanical forces likely play a central role. Previous studies have shown that cardiac torsion, which defines left-right directionality, is caused largely by forces exerted on the heart tube by a membrane called the splanchnopleure (SPL). Here we show that, when the SPL is removed from the embryonic chick heart, torsion is initially suppressed. Several hours later, however, normal torsion is restored. This delayed torsion coincides with increased myocardial stiffness, especially on the right side of the heart. Exposure to the myosin inhibitor Y-27632 suppressed both responses, suggesting that the delayed torsion is caused by an abnormal cytoskeletal contraction. This hypothesis is supported further by computational modeling. These results suggest that the looping embryonic heart has the ability to adapt to changes in the mechanical environment, which may play a regulatory role during morphogenesis.  相似文献   
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This article describes the principles and practice underlying the safe delivery of paediatric anaesthesia in the UK. It outlines the rationale behind the organization of paediatric anaesthetic services. The article describes the practicalities of creating an appropriate environment, and the equipment and techniques for general anaesthesia. Presenting an overview of the principles of paediatric anaesthesia, this article is complimented by specific articles in the series, which include principles of neonatal and day-case anaesthesia as well as dental and sedation procedures.  相似文献   
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