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961.
962.
PM Robitaille DP Rath TE Skinner AM Abduljalil RL Hamlin 《Canadian Metallurgical Quarterly》1993,30(2):262-266
In this work, we present the post-steady state analysis of the TCA cycle and a closed form solution to the rate of label washout from the C4 carbon of glutamic acid through the transaminases and the malate-aspartate shuttle and then through alpha-ketoglutarate dehydrogenase. We demonstrate using a model of this problem that the rate of label washout depends not only on the flux through alpha-ketoglutarate dehydrogenase, but most importantly on the activity of the malate-aspartate shuttle as determined by the forward and reverse fluxes through the transaminases and by the rate of transport of glutamate and alpha-ketoglutarate across the mitochondrial membrane. 相似文献
963.
964.
This article adds to the literature on the impact of computerized clinical information systems by asking nurses important questions about their nursing practices. A research tool was developed from collaborative work with clinicians who have used computers in their daily practice for more than two decades. A statewide study then was conducted on how nurses believed computer technology impacted their practice. This study also examined the different views that computer users and nonusers held. Questions were posed relating to resource consumption, nursing work practices, and professional and patient outcomes. It was found that nurses, whether computer naive or knowledgeable, clearly do not expect the technology to have negative impact on practice. The two groups differed mostly in the strength of their beliefs. One startling outcome, that slow computer response time delayed care, was identified within the computer-user group and direct action was taken as a result. 相似文献
965.
966.
M Sanicola C Hession D Worley P Carmillo C Ehrenfels L Walus S Robinson G Jaworski H Wei R Tizard A Whitty RB Pepinsky RL Cate 《Canadian Metallurgical Quarterly》1997,94(12):6238-6243
Glial cell line-derived neurotrophic factor (GDNF)-dependent activation of the tyrosine kinase receptor RET is necessary for kidney and enteric neuron development, and mutations in RET are associated with human diseases. Activation of RET by GDNF has been shown to require an accessory component, GDNFR-alpha (RETL1). We report the isolation and characterization of rat and human cDNAs for a novel cell-surface associated accessory protein, RETL2, that shares 49% identity with RETL1. Both RETL1 and RETL2 can mediate GDNF dependent phosphorylation of RET, but they exhibit different patterns of expression in fetal and adult tissues. The most striking differences in expression observed were in the adult central and peripheral nervous systems. In addition, the mechanisms by which the two accessory proteins facilitate the activation of RET by GDNF are quite distinct. In vitro binding experiments with soluble forms of RET, RETL1 and RETL2 demonstrate that while RETL1 binds GDNF tightly to form a membrane-associated complex which can then interact with RET, RETL2 only forms a high affinity complex with GDNF in the presence of RET. This strong RET dependence of the binding of RETL2 to GDNF was confirmed by FACS analysis on RETL1 and RETL2 expressing cells. Together with the recent discovery of a GDNF related protein, neurturin, these data raise the possibility that RETL1 and RETL2 have distinctive roles during development and in the nervous system of the adult. RETL1 and RETL2 represent new candidate susceptibility genes and/or modifier loci for RET-associated diseases. 相似文献
967.
RL Barrack 《Canadian Metallurgical Quarterly》1996,11(8):969-71; discussion 971-2
968.
969.
OBJECTIVE: To evaluate the validity, reliability, sensitivity, and specificity of the PaciTemp supralingual digital pacifier thermometer as compared to the Thermoscan Instant tympanic and glass-mercury rectal thermometers. METHOD: Eighty-one children under the age of 2 years had temperatures taken sequentially at three body sites: supralingual, tympanic, and rectal. Corrections were calculated between the readings of the three types of thermometers. Percentage of agreement was done to examine sensitivity and specificity. RESULTS: Using the glass-mercury measurement as the standard, both the supralingual and tympanic measurements showed an overall specificity of 62.8% and sensitivity of 63.3%. Correlation between rectal and supralingual was 0.62, and correlation between rectal and tympanic was 0.71. CONCLUSIONS: The Paci-Temp provides temperature readings that are similar to the tympanic method as compared to the rectal method. Further research on at-home thermometers is needed. 相似文献
970.
GP Uko M Griffiths RL Dawkins T Cobain I Mohammed C Hedo G Okafor AB Umotong 《Canadian Metallurgical Quarterly》1994,23(4):385-389
Concentrations of immunoglobulins (IgA, IgG and IgM) were measured in Nigerians with (HIV) infection. Considerable elevations up to two-fold the reference values were observed for IgG and IgM in the patient group as a whole but elevations in IgA concentration were least marked albeit significantly different from the healthy subjects. Elevation of a particular isotype was not always concomitant with elevation of the other major classes in the same patient. Overall, these elevations were observed in both symptomatic and asymptomatic infected subjects. Further analysis of IgG hyperglobulinemia showed that increases in this major class may be due to increased IgG2 subclass concentrations. It is suggested that elevation of IgG2 subclass in Nigerians with HIV infection and not IgG1 or IgG3 may be due to genetic and environmental factors rather than variation in the strain of the virus. 相似文献