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21.
H Rodgers M Sudlow R Dobson RA Kenny RG Thomson 《Canadian Metallurgical Quarterly》1997,47(418):309-310
The demand for anticoagulation services is rising. Warfarin anticoagulation has been shown to reduce the risk of stroke in patients with non-valvular atrial fibrillation by 68%. This raises issues about how services are best organized to initiate and monitor anticoagulation in this potentially large group of patients. We report the results of a regional postal survey undertaken to describe the views of general practitioners and consultants regarding warfarin anticoagulation in light of this potentially high increase in demand. 相似文献
22.
A.J. Roberts 《Computer Physics Communications》1997,100(3):215-230
I describe a method, particularly suitable to implementation by computer algebra, for the derivation of low-dimensional models of dynamical systems. The method is systematic and is based upon centre manifold theory. Computer code for the algorithm is relatively simple, robust and flexible. The method is applied to two examples: one a straightforward pitchwork bifurcation, and one being the dynamics of thin fluid films. 相似文献
23.
AF Minnick MJ Roberts WB Young RM Kleinpell RJ Marcantonio 《Canadian Metallurgical Quarterly》1997,35(4):399-409
OBJECTIVES: Market forces make it essential to know what policies and actions influence patients' reports of hospital services. No studies have examined the role of patient characteristics, labor quality and staff characteristics, nonlabor resources, managerial practices, and employee attitudes within a single investigation. METHODS: The authors collected, simultaneously, data about labor, management and service processes, nonlabor resources, and employee attitudes on 117 nonintensive medical-surgical inpatient units in 17 hospitals selected from a pool of 69 institutions within a metropolitan area by a stratified random sample. Of the 2,595 patients who agreed to participate, 2,051 (79%) completed telephone interviews regarding their experiences with physical care, education, and pain management services within 26 days of hospital discharge. RESULTS: A significant amount of variation in patients' service reports was explained (adjusted R2 = 0.41 physical care, 0.35 pain management, 0.44 education). Although the predictors varied for each service report, patient characteristics, especially those related to personal resources, had a large explanatory role. A labor assignment pattern that could explain why earlier studies found labor quality and staff characteristics to have only a weak role in the prediction of patients' service reports was noted. CONCLUSIONS: The results related to patient characteristics may indicate opportunities to improve care by confronting service design strategies that erroneously rely on a homogeneous patient population. Measurement challenges identified by this study must be addressed to determine the role of labor quantity and staff characteristics. 相似文献
24.
25.
Ingram M. Roberts 《Lipids》1985,20(4):243-247
A rapid, sensitive and convenient fluorescent assay was developed to screen for lipase activity. The non-fluorescent substrate,
4-methylumbelliferyl butyrate (4-MUB), solubilized in either liposomal dispersions or bile salt/lecithin mixed micelles, is
hydrolyzed to butyric acid and the highly fluorescent compound, 4-methylumbelliferone (4-MU). Assays are run at 37 C for 10
min, terminated, and the changes in fluorescence quantitated with a Turner III fluorometer. Both lingual and pancreatic lipases
exhibit activity against this artificial substrate. The assay has several advantages: nmoles 4 MU/ml/hr are measured allowing
the detection of very low lipolytic activity; multiple samples may be simultaneously assayed, and only a brief incubation
period is required. 相似文献
26.
Standards which eliminate ambiguity in reporting nonlinear phenomena, especially in the increasingly complex realm of biaxial crystals, are proposed. In order to restore uniformity to the designation of crystallographic axes and crystal tensor properties, adoption of IEEE/ANSI Std. 176, with a small but much needed modification for crystal class mm2, is recommended. For the reporting of nonlinear interaction characteristics, other frames are proposed which result in simpler rules than heretofore given for categorizing phase-matching loci, and for characterizing eigenmode polarizations, double refraction, effective nonlinear coupling, and first- and second-order acceptance bandwidths (angular, spectral, thermal) along these loci. Similarities as well as differences between biaxial and uniaxial crystals are emphasized 相似文献
27.
28.
Lewinsohn Peter M.; Roberts Robert E.; Seeley John R.; Rohde Paul; Gotlib Ian H.; Hops Hyman 《Canadian Metallurgical Quarterly》1994,103(2):302
In a prospective study of adolescent depression, adolescents (N?=?1,508) were assessed at Time 1 and after 1 yr (Time 2) on psychosocial variables hypothesized to be associated with depression. Most psychosocial variables were associated with current (n?=?45) depression. Formerly depressed adolescents (n?=?217) continued to differ from never depressed controls on many of the psychosocial variables. Many of the depression-related measures also acted as risk factors for future depression (n?=?112), especially past depression, current other mental disorders, past suicide attempt, internalizing behavior problems, and physical symptoms. Young women were more likely to be, to become, and to have been depressed. Controlling for the psychosocial variables eliminated the gender difference for current and future but not for past depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
29.
Intraneural injection of 10-20 x 10(6) viable Mycobacterium leprae into the sciatic nerve of normal, unsensitized, Swiss white mice gives rise to a tuberculoid type of granulomatous response in 2 weeks. The same dose of viable M. leprae when injected into the sciatic nerves of unsensitized immunosuppressed mice (T200 x 5R) elicited a macrophage response. When macrophages were systemically immobilized using an intraperitoneal injection of silica quartz dust in normal mice, the lesion produced was of the lepromatous type, suggesting a role for the macrophage in the induction of the tuberculoid type of granulomatous response. In all of these in situ experiments, M. leprae failed to enter the Schwann cells. 相似文献
30.
A Aliverti L Piubelli G Zanetti T Lübberstedt RG Herrmann B Curti 《Canadian Metallurgical Quarterly》1993,32(25):6374-6380
To investigate the functional role of the cysteine residues present in the spinach ferredoxin-NADP+ oxidoreductase, we individually replaced each of the five cysteine residues with serine using site-directed mutagenesis. All of the mutant reductases were correctly assembled in Escherichia coli except for the C42S mutant protein. C114S and C137S mutant enzymes apparently showed structural and kinetic properties very similar to those of the wild-type reductase. However, C272S and C132S mutations yielded enzymes with a decreased catalytic activity in the ferredoxin-dependent reaction (14 and 31% of the wild type, respectively). Whereas the C132S was fully competent in the diaphorase reaction, the C272S mutant flavoprotein showed a 35-fold reduction in catalytic efficiency with respect to the wild-type enzyme (0.4 versus 14.28 microM-1 s-1) due to a substantial decrease of kcat. NADP+ binding by the C272S mutant enzyme was apparently quantitatively the same (Kd = 37 microM) but qualitatively different, as shown by the differential spectrum. Stopped-flow experiments showed that the enzyme-FAD reduction rate was considerably decreased in the C272S mutant reductase, along with a much lower yield of the charge-transfer transient species. It is inferred from these data that the charge transfer (FAD-NADPH) between the reductase and NADPH is required for hydride transfer from the pyridine nucleotide to flavin to occur with a rate compatible with catalysis. 相似文献