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R Chandrashekar KC Curtis BW Rawot GS Kobayashi GJ Weil 《Canadian Metallurgical Quarterly》1997,35(5):1071-1076
We recorded simultaneous multichannel electroencephalogram (EEG) and magnetoencephalogram (MEG) in four children with partial epilepsy. Sources of averaged spikes were modelled with current dipoles. Of 10 spike averages obtained, three peaked simultaneously in MEG and EEG, and in seven averages, the MEG peak preceded the main EEG peak by 9-40 ms. A small positive early EEG signal coincided with the MEG peak in six asynchronous spikes. The simultaneous MEG and EEG spikes originated within 5-23 mm, while sources of asynchronous peaks were 12-67 mm apart. We conclude that non-identical neurone currents underlie the MEG and EEG signals, and emphasize the importance of modelling early phases of EEG spikes when localizing interictal epileptic zones. 相似文献
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GS Taylor Y Liu C Baskerville H Charbonneau 《Canadian Metallurgical Quarterly》1997,272(38):24054-24063
The essential CDC14 gene of the budding yeast, Saccharomyces cerevisiae, encodes a 62-kDa protein containing a sequence that conforms to the active site motif found in all enzymes of the protein tyrosine phosphatase superfamily. Genetic studies suggest that Cdc14p may be involved in the initiation of DNA replication, but its precise cell cycle function is unknown. Recombinant Cdc14p was produced in bacteria, characterized, and shown to be a dual specificity protein phosphatase. Polyanions such as polyglutamate and double-stranded and single-stranded DNA bind to Cdc14p and affect its activity. Native molecular weights of 131,000 and 169,000 determined by two independent methods indicate that recombinant Cdc14p self-associates in vitro to form active oligomers. The catalytically inactive Cdc14p C283S/R289A mutant is not able to suppress the temperature sensitivity of a cdc14-1(ts) mutant nor replace the wild type gene in vivo, demonstrating that phosphatase activity is required for the cell cycle function of Cdc14p. A distinctive COOH-terminal segment (residues 375-551) is rich in Asn and Ser residues, carries a net positive charge, and contains two tandem 21-residue repeats. This COOH-terminal segment is not required for activity, for oligomerization, or for the critical cell cycle function of Cdc14p. 相似文献
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GS Allen FA Moore CS Cox JT Wilson JM Cohn JH Duke 《Canadian Metallurgical Quarterly》1998,45(1):69-75; discussion 75-8
BACKGROUND: The incidence of hollow viscus injury (HVI) after blunt trauma (BT) is variable, and differences between children and adults have not been well described. The purpose of this study is to determine the age-group-related incidence and characteristics of BT-associated HVI as well as the clinical markers and consequences of delayed diagnosis. METHODS: A 9-year trauma registry review of all patients with HVI. RESULTS: A large sample of patients (19,621) with BT were evaluated (2,550 < or = 14 years old; 17,070 > 14 years old). One hundred thirty-nine of 17,070 (0.8%) adults had HVI compared with 27 of 2,550 (1%) children. HVI occurred more frequently in the duodenum in children (11 of 27) compared with adults (17 of 139) (p < 0.05). Among patients with abdominal wall ecchymosis, 13.5% of children had HVI compared with 10.6% of adults. Delays in diagnosis of HVI occurred in 9 of 27 children compared with 10 of 139 adults (p < 0.0 5). Delayed diagnosis was associated with increased abdominal septic complications in both children (4 of 9) and adults (2 of 10) compared with diagnosis at presentation (p < 0.05). CONCLUSION: HVI occurs with a similar low frequency in both children and adults. Duodenal injuries are more common in pediatric BT patients. Abdominal wall ecchymosis is associated with increased HVI but is less predictive of HVI than previously described. Contrary to previous reports, delays in diagnosis are associated with increased morbidity. 相似文献