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81.
82.
The organization of patient care in many acute care institutions lacks a foundation in nursing theory, yet preliminary evidence of the value of professional nursing care is increasing. The process and preliminary benefits of organizing patient care according to a professional practice model are presented using a collaborative partnership between an acute care organization and a school of nursing. A pilot implementation plan with formative and summative evaluation provided preliminary evidence used in project expansion.  相似文献   
83.
High acuity in client populations has placed increasing demands on novice nurses to apply concepts of clinical reasoning to nursing practice. To assist nursing students in developing clinical reasoning skills, an exercise called "Friday Night in the Pediatric Emergency Department" was designed to give students real-time experiences in triage situations using a simulated clinical experience in a classroom setting. The author describes the exercise and its impact on the clinical reasoning skills of undergraduate nursing students.  相似文献   
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The cytotoxic mechanism of diphtheria toxin (DTx) is associated with its ability to inhibit protein synthesis by ADP-ribosylation of elongation factor 2. Although DTx intoxication leads to internucleosomal DNA cleavage and cell lysis, these events do not occur when protein synthesis is inhibited by alternative treatments (e.g., cycloheximide). Here we show that endonucleolytic degradation of DNA is an intrinsic activity of DTx and also of the crossreactive mutant protein CRM197. Assays using DNA-impregnated gels as well as linear and supercoiled DNA in solution revealed not only that CRM197 has nuclease activity but also that its specific activity is actually significantly greater than that of the wild-type molecule. Since CRM197 contains a single amino acid substitution that renders it incapable of ADP-ribosylation, we propose that the active sites for ADP-ribosyltransferase and nuclease activities are distinct.  相似文献   
86.
The history of developmental and genetic analysis in the mouse has made it the model of choice for studying mammalian embryogenesis. Presently lacking is a simple technique for efficiently analyzing early mouse mutant phenotypes in utero. We demonstrate application of a real-time imaging method called ultrasound backscatter microscopy for visualizing mouse early embryonic neural tubes and hearts. This method was used to study live embryos in utero between 9.5 and 11.5 days of embryogenesis, with a spatial resolution close to 50 microns. Ultrasound backscatter microscope images of cultured embryos made it possible to visualize the heart chambers. This noninvasive imaging method was also used for analyzing a neural tube defect. The midhindbrain deletion associated with a null mutation of the Wnt-1 protooncogene was easily recognizable on ultrasound backscatter microscope images of 10.5- and 11.5-day embryos. Computer-generated volumetric renderings of the neural tube cavities were made from three-dimensional image data. This allowed a much clearer definition of the Wnt-1 mutant phenotype. These imaging techniques should be of considerable use in studying mouse development in utero.  相似文献   
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There is limited large-scale empirical research into the working lives of adults who have an autism spectrum disorder with no co-occurring intellectual disability. Drawing on data from a national survey, this report describes the employment activities and experiences of 130 adults with Asperger’s Disorder (AD) and high functioning autism (HFA) in Australia. Outcome measures include current occupation; occupational skill level and alignment with educational attainment; type of job contract; hours of work; support received to find work; support received in the workplace; and positive and negative experiences of employment. The findings confirm and expand upon existing evidence that adults with AD and HFA, despite their capacity and willingness to work, face significant disadvantages in the labour market and a lack of understanding and support in employment settings.  相似文献   
90.
Epithelial-to-mesenchymal transition (EMT) of endocardial cells is a critical initial step in the formation of heart valves. The collagen gel in vitro model has provided significant information on the role of growth factors regulating EMT but has not permitted investigation of mechanical factors. Therefore we sought to develop a system to probe the effects of mechanical inputs on endocardial EMT by incorporating hyaluronic acid (HA), the primary component of endocardial cushions in developing heart valves, into the gel assay. This was achieved using a combination collagen and crosslinkable methacrylated HA hydrogel (Coll-MeHA). Avian atrioventricular canal explants on Coll-MeHA gels showed increased numbers of transformed cells. Analysis of the mechanical properties of Coll-MeHA gels shows that stiffness does not directly affect EMT. Hydrogel deformation from the beating myocardium of explants directly led to higher levels of regional gel deformation and larger average strain magnitudes associated with invaded cells on Coll-MeHA gels. Inhibition of this contraction reduced EMT on all gel types, although to a lesser extent on Coll-MeHA gels. Using the system we have developed, which permits the manipulation of mechanical factors, we have demonstrated that active mechanical forces play a role in the regulation of endocardial EMT.  相似文献   
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