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81.
82.
As you read this issue of the Journal and celebrate OR Nurse Week, think about your daily opportunities to practice the principles of international nursing. Look for chances to appreciate cultural values different from your own as you provide patient care and interact with visiting international colleagues. Adopt a global perspective to perioperative nursing.  相似文献   
83.
Here we present a fiber-optic seismic waves sensor based on in-fiber Bragg gratings. Fiber-Bragg-grating (FBG) sensors have been demonstrated to have very high sensitivity to dynamical strain and very extended dynamical response. The seismic sensing system is based on the integration of three FBGs' dynamical strain sensors in a mechanical structure acting as an inverse pendulum. Polar symmetry of the mechanical system and 120deg placement of the FBG sensors could enable directional capability of the seismic sensor. Design, manufacturing, and preliminary dynamical testing of the seismic sensor are discussed.  相似文献   
84.
In Drosophila, Sxl functions as a binary switch in sex determination. Under the control of the primary sex-determining signal, it produces functional protein only in XX animals to implement female development. Here we report that, in contrast to Drosophila, the Sxl homologue in the Medfly, Ceratitis capitata, expresses the same mRNAs and protein isoforms in both XX and XY animals irrespective of the primary sex-determining signal. Also, experiments with two inducible transgenes demonstrate that the corresponding Ceratitis SXL product has no significant sex-transforming effects when expressed in Drosophila. Similar results have been obtained for the Sxl homologue of Musca domestica (Meise, M., Hilfiker-Kleiner, D., Brunner, C., D?bendorfer, A., N?thiger, R. and Bopp, D. (1998) Development 125, 1487-1494). Our findings suggest that Sxl acquired its master regulatory role in sex determination during evolution of the Acalyptratae group, most probably after phylogenetic divergence of the genus Drosophila from other genera of this group.  相似文献   
85.
Growth-inhibitory activities of selected natural benzofurans (4-9), trans-cinnamic acid derivatives (10-13), chromene compounds (14 and 16), and some semisynthetic derivatives were determined in last instar larvae of Tenebrio molitor via topical administration in Me2CO. The most inhibitory of the tested compounds were 3-gamma, gamma-dimethylallyl-p-coumaric acid (10) and the benzofuran derivative 12-(p-cumaroyloxy)-tremetone (5), the former compound acting on the pupae and the latter on the last instar larvae. Several developmental deficiencies were observed, and some structure-activity relationships are discussed.  相似文献   
86.
The kinetics of oxygen reduction have been studied at Nafion®-coated dual layer gas-diffusion electrodes at 60 °C in 2.5 M H2SO4. A.c. impedance and steady state galvanostatic measurements have been carried out on electrodes containing various PTFE loadings. A.c. impedance spectroscopy supplied information on charge transfer resistance, series resistance and double layer capacitance of electrodes during the oxygen reduction process. These parameters, together with those derived by d.c. measurements (i.e. Tafel slopes, charge transfer coefficient, etc.), allowed a better identification of the features governing the electrode efficiency and the reduction mechanism. The best electrode was found to be one containing 30% PTFE; this showed both the lowest charge transfer resistance and the lowest overpotential for oxygen reduction. This electrode also showed lower overpotential than the same uncoated electrode at low current densities. The poisoning effect by methanol has been also investigated. Upon addition of methanol to the solution, no change was observed in the reaction mechanism at low overpotentials. In contrast, a significant variation of the Tafel slope was observed at high overpotentials. This behaviour is interpreted in terms of the variation of Pt-O bond strength as a function of electrode potential.  相似文献   
87.
Examined the effectiveness of child-centered play therapy sessions every day for 2 wks as an intervention for child witnesses of domestic violence. 22 children (aged 4–10 yrs) participated. The analyses of covariance indicated that children in the experimental group experience a significant increase in self-concept, a significant decrease in external and total behavior problems, a significant increase in the play behavior of physical proximity to the therapist, and a significant increase in the play behavior of nurturing and creative play themes. The results support utilizing intensive play therapy to treat child witnesses of domestic violence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
88.
BACKGROUND: The hemodynamic significance of patent mammary graft side branches is still controversial. This study was designed to evaluate the potential for flow steal of patent mammary side branches in different hemodynamic conditions. METHODS: Echo-Doppler measurement of mammary graft flow was performed at rest and after dipyridamole-induced coronary vasodilatation in 10 patients with angiographic demonstration of evident mammary graft side branches (study group) and in 10 matched control patients (control group). Concomitant thallium-201 myocardial scintigraphy was performed to assess the adequacy of mammary flow to the myocardial oxygen demand. Patients of the study group were also submitted to flow evaluation in condition of selective muscular or combined systemic and coronary relaxation. RESULTS: No difference in mammary flow and adequacy to myocardial oxygen demand was detected between patients of the study and control groups both at rest and after dipyridamole infusion. In patients with patent side branches the systolic-to-diastolic flow ratio was maintained in case of combined coronary and peripheral vasodilatation, whereas selective muscular relaxation led to an increase in the systolic and a reduction in the diastolic flow. CONCLUSIONS: Flow steal from patent mammary graft side branches is possible only in case of selective muscular vasodilatation. As this situation is unlikely to occur in the clinical setting, the potential for flow steal of mammary side branches in cardiac surgery patients seems to be minimal.  相似文献   
89.
Concept formation from design cases: why reusing experience and why not   总被引:1,自引:0,他引:1  
This paper describes an environment that supports novice information systems designers in initial concept formation by organising design `cases' in evolving networks, automatically clustered by a neural agent to suggest generalisations of design patterns. Flexible reframing of the cases also supports creativity by uncovering less obvious but relevant design concepts. If the responsibility, of linking related design cases is distributed to a population of learners who contribute their cases and tentative generalisations, genetic techniques can be applied to sustain the evolution of the base of cases towards ontological forms that better guide and constrain the case reuse process, thus supporting knowledge transfer.  相似文献   
90.
BACKGROUND: Although not common, rectal prolapse in adults can often be a debilitating conditions. Its only effective treatment is surgical. Among the many procedures described for the treatment of rectal prolapse, abdominal rectopexy is one of the preferred. It consists of fixation of the rectum to the sacrum and does not require any intestinal resection or anastomosis. However, like all open abdominal surgery associated with a large incision this operation may result in significant morbidity which is exacerbated by the advanced age of the patient. METHODS: An abdominal rectopexy carried out completely laparoscopically is described. The rectum is fully mobilised down to the pelvic floor and then fixed to the sacrum employing a polypropylene mesh. The mesh is first stapled to the sacral hollow and then sutured on both sides of the rectum. Thus the mesh is wrapped around the lateral aspects of the rectum, but the anterior rectal wall is left free. Laparoscopic techniques have been applied to a wide range of benign and malignant colorectal procedures. RESULTS: However most of colorectal laparoscopic techniques involving bowel resection, are technically demanding and require often an abdominal incision to deliver the specimen and fashion the anastomosis. CONCLUSIONS: Without the need for bowel resection, the laparoscopic rectopexy may constitute an optimal application of laparoscopic colorectal techniques and may soon become the gold standard for the treatment of rectal prolapse.  相似文献   
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