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191.
SM Haslam GC Coles EA Munn TS Smith HF Smith HR Morris A Dell 《Canadian Metallurgical Quarterly》1996,271(48):30561-30570
Structural studies on the N-linked oligosaccharides of Haemonchus contortus, an economically important nematode that parasitizes domestic ruminants, have revealed core fucosylation of a type not previously observed in any eukaryotic glycoprotein. Mass spectrometric analyses were performed on detergent extracts of homogenized adult H. contortus and on purified H11, a glycoprotein isolated from intestinal brush borders which has been previously shown to be an effective vaccine antigen. The major N-linked glycans identified in the present study have up to three fucose residues attached to their chitobiose cores. The fucoses are found at the 3- and/or 6-positions of the proximal GlcNAc and at the 3-position of the distal GlcNAc. The latter substitution is unique in N-glycans. Most anti-H11 monoclonal antibodies are known to recognize carbohydrate epitopes, and it is possible that the newly discovered multifucosylated core structures are highly immunogenic in this glycoprotein. 相似文献
192.
EA Dean-Nystrom BT Bosworth HW Moon AD O'Brien 《Canadian Metallurgical Quarterly》1998,66(9):4560-4563
Enterohemorrhagic Escherichia coli (EHEC) strains require intimin to induce attaching and effacing (A/E) lesions in newborn piglets. Infection of newborn calves with intimin-positive or intimin-negative EHEC O157:H7 demonstrated that intimin is needed for colonization, A/E lesions, and disease in cattle. These results suggest that experiments to determine if intimin-based vaccines reduce O157:H7 levels in cattle are warranted. 相似文献
193.
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195.
KN Furuya PR Durie EA Roberts SJ Soldin Z Verjee L Yung-Jato E Giesbrecht L Ellis 《Canadian Metallurgical Quarterly》1995,28(5):531-540
N-Acetyl aspartate (NAA) is the second most abundant amino acid in the human brain. NAA is synthesized by L-aspartate N-acetyl transferase or by cleavage from N-acetyl aspartyl glutamate by N-acylated alpha-linked L-amino dipeptidase (NAALADase); and it is catabolized to acetate and aspartate by N-acetyl aspartate amino hydrolase (amino acylase II). NAA is localized primarily to neurons, where it is concentrated in the cytosol. Although NAA is devoid of neurophysiological effects, it serves as an acetyl donor, an initiator of protein synthesis or a carbon transfer source across the mitochondrial membrane. The concentration of NAA in human brain increases 3-fold between midgestation and adulthood. In Canavan's Disease, an autosomal recessive disorder due to a null mutation in amino acylase II, NAA levels in brain are markedly increased and disrupt myelination. NAA levels have been found to be reduced in neurodegenerative disorders, including Alzheimer's Disease and Huntington's Disease. Since endogenous NAA can be readily detected in human brain by magnetic resonance spectroscopy, it is increasingly being exploited as a marker for functional and structural integrity of neurons in an expanding number of disorders. 相似文献
196.
Data from an anonymous survey of 3,690 adolescents were used to assess how much of the unique variance in adolescents' self-reported drug use was accounted for by number of parents in comparison to the adolescents' sex, age, social class, and peer drug use. Multiple regression revealed that the contribution of number of parents was small and nonsignificant compared to peer use, student age, parental occupation and remarriage, student sex, and parental unemployment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
197.
AV Nedostup EA Bogdanova EI Mikhnovski? AA Platonova 《Canadian Metallurgical Quarterly》1977,17(4):85-90
The structure of cardiac rhythm was studied with the help of specialized computers during digitalization in 60 patients with atrial fibrillation of different etiology. The reduction of the heart contractions rate under digitalization is accompanied by certain changes in the structure of cardiac rhythm: the arrhythmic pattern of the ventricular contractions increases with a predominant growth of the number of long R--R intervals, the transitions from short intervals to longer ones become sharper, and portions of a relatively stable ventricular rhythm appear. Three main types of dynamics of the rhythm structure were distinguished on the basis of the changes in the interval R--R histogram. The described changes in the structure of cardiac rhythm are not specific, but when Digitalis drugs are used alone they can be used as additional criteria for digitalization. 相似文献
198.
Although patients taking phenformin are more likely to develop lactic acidosis in the presence of renal, cardiovascular, or hepatic disease, criteria for safe use of the drug are not well established. Eight diabetics died of lactic acidosis in Nottingham in 1972-5 and all were taking phenformin in therapeutic doses. Six had attended the diabetic clinic within a month of their terminal illness. Two patients had appreciable renal impairment and should not have been given phenformin. Four had hypertension and minimal evidence of renal disease, while in two no predisposing factor was identified. There are so many contraindications to the use of phenformin that it is doubtful whether patients on the drug can be monitored adequately. We suggest that phenformin should be withdrawn from general use. 相似文献
199.
The dynamics of the ultrastructure of the neurosecretory system in the postburn period is characterized by phasic of organells of neurosecretory cells and synapses on their bodies and processes. Immediately after burn there appear pronounced signs of an increased formation of secretion synchronous to a considerably increased functional activity of synaptic structures. Of the opposite character are fine structures in neurocytes in the subsequent period (1-1,5 hour after burn). Phenomena of disintegration and degeneration of organells are developing in the cells. In the posiologically active neurohormones and degeneration of membrane structures gradually increase at all the observed stages of the burn trauma. All the elements of the supraoptic nucleus and the posterior lobe of the hypophysis early responding to the effect of such a powerful extreme factor are involved in the response of the organism to burn. It should be noted that immediately after burn there appears an increased permeability of capillaries followed by extravasation of formed elements and liquid blood. It steadily increases with the development of the process. 相似文献
200.
A study of the physiological behaviour of the synthetic compound Orthonil (alpha-chloro-beta-(3-chloro-o-tolyl)-propionitrile revealed a strong auxin activity in higher plants. Otherwise, Orthonil appeared not to be a herbicide-auxin. It is metabolized intensively in plant tissues. Among the identified metabolites, two compounds were detected which also exert a high auxin activity. It is concluded that at least a part of the apparent auxin activity of Orthonil may be due to alpha-(3-chloro-o-tolyl) acetic acid, one metabolite of Orthonil. Although Orthonil strongly stimulates elongation growth, this growth is not accompanied by a stimulated ethylene evolution as is the case with other auxins. A possible metabolic pathway of Orthonil is discussed. 相似文献