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1.
A new range of stand magnifiers has been released by the COIL company in the United Kingdom. Examination of these magnifiers reveals that they fail to deliver the rated magnifications labelled prominently on the appliances, as a result of the manufacturer's conformance with the requirements of the German DIN standard and the use of back vertex power (F'v) rather than equivalent dioptric power (Fm) of the magnifier. In this study we provide information on the optometric parameters of these new stand magnifiers that will assist the more accurate specification of improvements in vision expected from their use. 相似文献
2.
J. E. Hammond R. G. Berger T. S. Carey R. Rutledge T. J. Cleveland J. P. Kichak C. F. Ayscue 《Journal of medical systems》1991,15(3):257-267
Many hospitals today have implemented widely disparate information systems on mainframe and mini-computer hardware. The advent of network technology in hospitals has made it possible to access information in these systems. Unfortunately, the user interfaces to applications on these systems are unique and difficult to learn, which makes them unsuitable for use by clinical services. In this paper we describe the development of a Physician's Workstation which integrates information from multiple existing information systems and discuss how the workstation makes it possible to move from the departmental systems of the present to the computer-based medical record system of the future. 相似文献
3.
The limitations of current methods of measuring bilirubin are well established and relate to the broad dynamic range and inability of the technique to determine different but structurally similar bilirubin species. New instrumentation and methodology circumvent these limitations, and clinical studies are beginning to reveal their increased diagnostic usefulness. Nevertheless, in several clinical situations, for example, the prediction of kernicterus, better bilirubin determinations may not eliminate the controversy surrounding appropriate therapeutic interventions. 相似文献
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J R Dimmock K M Advikolanu H E Scott M J Duffy R S Reid J W Quail Z Jia R A Hickie T M Allen J M Rutledge 《Journal of pharmaceutical sciences》1992,81(12):1147-1152
Mannich bases were synthesized and converted to the corresponding arylhydrazones. X-ray analysis of a ketone (1a) and a hydrazone (4d) revealed structural features of interest. All of the compounds showed cytotoxicity toward murine lymphocytic leukemia L1210 cells in the 4.9-25.0-microM range. The correlation coefficients generated by plotting the IC50 values (the concentrations of compounds that inhibit the growth of tumors by 50%) of some hydrazones against certain electronic, hydrophobic, and steric constants of the aryl substituents indicated only weak correlations. A few ketones and hydrazones displayed significant cytotoxicity to the WiDr human colon cancer cells, and these derivatives, especially the ketones, may serve as prototypes for future drug development. The KB tumor (a human epidermoid carcinoma of the nasopharynx) was somewhat refractory to selected compounds. In an in vitro assay conducted by the National Cancer Institute and involving approximately 53 tumor cell lines originating from eight neoplastic diseases, 65% of the compounds showed some selectivity toward one or more groups of cancers, principally leukemia, melanoma, and colon cancer. The bioevaluation of the ketones and hydrazones against the L1210, WiDr, and KB tumors, as well as evidence from proton nuclear magnetic resonance studies did not support the suggestion that hydrazones may be prodrugs of the corresponding ketones. 相似文献
6.
Pheochromocytoma and paraganglioma: comparison of MR imaging with CT and I-131 MIBG scintigraphy 总被引:6,自引:0,他引:6
To ascertain the magnetic resonance (MR) imaging characteristics of pheochromocytomas and paragangliomas and to compare MR with computed tomography (CT) and iodine-131 metaiodobenzylguanidine (I-131 MIBG), 19 patients (18 with pheochromocytomas, one with a paraganglioma) were studied. The 18 patients with pheochromocytomas had had positive findings with I-131 MIBG scintigraphy. Abdominal pheochromocytomas were generally hypointense compared with normal liver on T1-weighted MR images and extremely hyperintense on T2-weighted MR images. MR imaging was preferable to CT in the evaluation of primary pheochromocytomas due to superior tissue characterization, particularly in the patient with hypertension and borderline catecholamine levels. For patients with recurrent or metastatic disease, the data suggest that I-131 MIBG scintigraphy is the examination of choice. 相似文献
7.
B Rutledge 《The Journal of neuroscience nursing》1989,21(6):370-374
Aneurysm wrapping is an uncommon procedure used only when clipping or ligature is not feasible. This article contains a brief discussion of the various modalities of aneurysm wrapping in its early years, product options available today, characteristics and manifestations of intracranial aneurysms and a synopsis of the surgical procedure. In addition, perioperative nursing care is discussed. 相似文献
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9.
An analysis of the association of trauma centers with per capita hospitalizations and death rates from injury. 总被引:1,自引:1,他引:0 下载免费PDF全文
OBJECTIVE: This study used population-based data bases to assess the association of trauma centers with per capita county hospitalization and trauma death rates in the State of North Carolina. SUMMARY BACKGROUND DATA: The current study extended previous work using two North Carolina data bases to assess the association of the presence of a trauma center with per capita county trauma death rates. METHODS: Data on per capita county trauma hospitalizations and deaths were obtained from the state hospital discharge data base and the North Carolina Medical Examiner's data base. Bivariate and multivariate analysis techniques were used. The dependent variables of interest were prehospital, hospital, and total trauma death rates and hospitalization rates for injury. RESULTS: Bivariate analysis identified a number of factors associated with per capita county hospitalizations and trauma death rates. These included the per cent unemployment, racial distribution, county alcohol tax receipts, and advanced life support certified emergency medical services providers. The per capita trauma death rates were significantly lower in counties with trauma centers compared with those without trauma centers (4.0 +/- 0.5 and 5.0 +/- 1.1 deaths per 10,000 population, p = 0.0001, respectively). The per capita hospitalizations for trauma were also lower in counties with trauma centers. Multivariate modeling showed that the presence of a trauma center and advanced life support providers were the best predictors of decreased per capita county trauma death rates. CONCLUSIONS: The study showed that the presence of a trauma center and advanced life support training were the two medical system factors that were the best predictors of the per capita county prehospital and total trauma death rates. These findings are consistent with the hypothesis that trauma centers are associated with a decrease in trauma death rates. 相似文献
10.