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61.
A sample of 42 case notes of alcoholic patients were abstracted for 17 items by three different raters. Interrater agreement was generally rather low. Research based on case-note abstraction which does not report on abstraction reliabilities must therefore be viewed with some suspicion. It would be helpful if clinical material could more often be collected in a standardized manner. 相似文献
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JJ Ellestad-Sayed RA Nelson MA Adson WM Palmer EH Soule 《Canadian Metallurgical Quarterly》1976,29(12):1333-1338
To investigate further an apparent relationship between chronic ulcerative and granulomatous colitis and pantothenic acid deficiency, colonic tissues obtained at the time of colectomy in 29 patients with these disorders were assayed for pantothenic acid and for coenzyme A (CoA) activity. For comparison, normal colonic tissues free of pathological lesions were obtained from 31 patients having colectomy for carcinoma or diverticulitis. Plasma, red blood cells, and colonic mucosa were assayed microbiologically for free and total pantothenic acid. The activity of CoA in colonic mucosa was determined by assaying the acetylation of sulfanilamide. Concentrations of free, bound, and total pantothenic acid in blood and in colonic mucosa did not differ between the two groups of patients. Bound pantothenic acid increased linearly with total pantothenic acid. Colonic mucosa concentrated free pantothenic acid to about 50 times the level of blood, and pantothenic acid in red cells was similar to the concentration in plasma. Compared to normal gut mucosa, CoA activity was markedly low in mucosa from patients with chronic ulcerative or granulomatous disease despite the presence of normal amounts of free and bound pantothenic acid. A block in the conversion of bound pantothenic acid to CoA in diseased mucosa is suggested. 相似文献
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Norman Epstein 《加拿大化工杂志》1981,59(6):649-657
The most recent review by østergaard — on the fluid mechanics of three-phase fluidized beds — is updated and broadened, and the more manifest knowledge gaps are identified. A systematic classification of the various modes of three-phase fluidization is presented in order to provide some perspective on the research which has been done and on that which has yet to be done. 相似文献
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The several possible solutions to the problem of creeping flow relative to an isolated permeable sphere are discussed and compared quantitatively. The most satisfactory solutions is that based upon Brinkman's extension of Darcy's Law. This solution is generalized, using Happel's free-surface model, to cover the practically important problem of flow relative to a swarm of permeable spheres. A physically realistic and mathematically consistent expression for the hydrodynamic resistance experienced by a typical sphere within such a system is derived. This expression is then used to predict the settling rate and the overall permeability of the swarm. 相似文献
70.
EH Nielsen 《Canadian Metallurgical Quarterly》1976,173(2):179-191
Unilateral electrolytic lesions of the locus coeruleus in rats result in spontaneous ipsiversive rotation, which is then replaced by contraversive rotation. One week after lesioning, when spontaneous turning ceases, apomorphine and d-amphetamine elicit contraversive circling behaviour, which was not affected by noradrenergic receptor blockade but was abolished by dopamine receptor blockade. The drug-induced contraversive circling response was also reproduced by piribedil but not clonidine. Combined unilateral electrolytic locus coeruleus and substantia nigra lesions on the same side resulted in apomorphine- and d-amphetamine-induced ipsilateral rotational behaviour which was indistinguishable from that seen with substantia nigra lesions alone. In rats with unilateral locus coeruleus lesions, the dose of intrastriatally injected apomorphine required to produce circling was less on the lesioned than the non-lesioned side. Direct injection of noradrenaline into one substantia nigra caused contraversive circling. Direct injection of phenoxybenzamine into one substantia nigra followed by apomorphine caused ipsiversive circling. The results suggest that the circling behaviour seen after unilateral locus coeruleus lesions depends on an asymmetry of striatal dopamine receptor activity and are consistent with a proposed coeruleus-nigral noradrenergic pathway, which enhances impulse flow in the dopaminergic nigrostriatal system. 相似文献