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The purpose of this study is to evaluate the effect of one abrasive cleaner, one non-abrasive cleaner and one non-abrasive alcohol-based cleaner on the lens parameter stability of the NOVALENS. Twenty-four lenses, all NOVALENS material of identical design, were cleaned 100 times each. Eight lenses were cleaned with MiraFlow (CIBA Vision), eight lenses with Optic-Free Daily Cleaner and eight lenses with the Gas Permeable Daily Cleaner (PBH). The base curve radius, center thickness and power were verified immediately before, immediately after and (per manufacturer's recommendation) 4 hours after cleaning at baseline, 25, 50, 75 and 100 cleanings. Lens toricity of approximately 0.50D was found with all three cleaners after 100 cleanings. No change in lens power or center thickness was found. It was concluded that extreme care must be taken in handling the NOVALENS due to the potential of induced warpage. 相似文献
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The evidence suggests that enrolled nurses and those working part-time and on night duty consistently attend less continuing professional education than their more senior, full-time and day duty colleagues. This was substantiated in the findings of this study which also highlighted the paucity of opportunities for continuing education among unqualified practitioners. In the light of recent developments within the health services, this inequitable provision of continuing professional education to all nursing practitioners will need to be addressed and resolved. Continuing professional education provided on an arbitrary and random basis will not afford maximum positive outcomes for clients, the service and practitioners and has the potential to increase the levels of frustration among disadvantaged groups of nursing staff. 相似文献
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KL Miller 《Canadian Metallurgical Quarterly》1994,6(4):785-803
Endocrine disorders in critically ill infants and children can be the manifestation of an existing but previously unrecognized condition, or hormonal derangements precipitated by deleterious effects on endocrine function of a critical illness or its prescribed therapy. To achieve successful resolution of these crises, a general understanding of various endocrine dysfunctions, clinical symptomatology, diagnosis, and medical and nursing management is essential. 相似文献
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Administered to 20 chronic, undifferentiated schizophrenics and 20 paranoid schizophrenic controls the release-from-proactive-interference procedure as developed by D. D. Wickens. Word triads representing 8 conceptual categories were the to-be-remembered stimuli. Proactive interference release was clearly established for both schizophrenic subgroups. These findings are interpreted to imply that chronic, undifferentiated schizophrenics as well as paranoid schizophrenics encode the attributes of conceptual word class in memory. Previous failures of chronic schizophrenics to benefit from categorized to-be-remembered materials in recall tests are probably not the result of an encoding deficiency. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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A family is described in which the mother and 2 of the 5 children had Felty's syndrome, a pattern of inheritance suggesting a dominant defect and one which has not previously been reported. The family is also of interest in that the other sib had rheumatoid arthritis. 相似文献
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Fixation of prosthetic joint components into bone is influenced by the degree of mechanical interdigitation of the acrylic into cancellous interstices. The rheology of polymerizing polymethylmethacrylate was studied by pressurizing acrylic bone cement with a piston apparatus to produce flow into cylindrical cavities one to 3 mm in diameter. The acrylic penetration per unit of applied pressure increased with increasing cavity diameter. This suggests that greater penetration should occur in cancellous bone containing larger interstitial cavities. More than one-half (64 %) of the filling observed in our experiments took place within the first second of pressure application. Short duration, high level pressure pulses are the most effective means to achieve maximum penetration. Clinically, this is accomplished by vigorous finger packing. The cement should be pressurized as early as possible within the rasped cavity (immediately after dough stage if possible). The depth of penetration for 4-minute pressurization averaged three times that for 6 1/2-minute pressurization for the range of hole sizes and pressure levels tested. 相似文献