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831.
Carbamazepine (CBZ) is an effective anticonvulsant agent. Current literature reports describe several cases of seizure exacerbation and/or EEG worsening due to CBZ with a high prevalence in children and adolescents; we report 10 new cases. Nine patients had epilepsy; one showed delayed psychomotor development and frequent EEG paroxysmal abnormalities. Four patients were on monotherapy, six on polytherapy. All but one had therapeutic CBZ plasma concentrations. Seizures increased in frequency in nine, and in eight patients new seizure types appeared, mostly absences. Cognitive functions/behaviour worsened in eight; EEG recordings showed slowing background activity and increased paroxysmal abnormalities, in six cases diffuse/generalized spike waves were seen and in two continuous spike wave discharges. The mean time of clinical EEG worsening was 1-2 days after introduction of CBZ at therapeutic doses. After CBZ withdrawal clinical EEG improvement was evident in a few days. The underlying pathogenetic mechanism is not yet understood. However, the pathophysiology of seizure exacerbation might be related to the interaction between age-related alterations in the balance of excitation and inhibition in the developing thalamocortical circuitry and the essential activity of CBZ that tends to induce interictal discharges. 相似文献
832.
833.
The paper describes a Computer Aided Software Engineering (CASE) tool to support conceptual database modelling. One popular approach for conceptual database modelling is use of the Entity-Relationship (ER) model. The paper proposes the use of an Enhanced Entity-Relationship (EER) model for conceptual database modelling. This Enhanced Entity-Relationship model extends the Entity-Relationship model by incorporating the generalization/specialization, aggregation and categorization abstractions. The CASE tool, which is based on the Enhanced Entity-Relationship model, is known as the Enhanced Entity-Relationship Diagrammer (EERD). In addition, the CASE tool supports direct visual query and update based on the EERM. 相似文献
834.
MP Vawter J Basaric-Keys Y Li DS Lester RS Lebovics KP Lesch H Kulaga WJ Freed T Sunderland B Wolozin 《Canadian Metallurgical Quarterly》1996,142(1):179-194
Olfactory neuroepithelial cells (ONC) grown from biopsies of human donors are a novel cell culture system that may facilitate studies into normal and disease-related human neurobiology. We further characterized the expression of cell surface markers and intermediate filaments, and responses to neurotrophic factors by ONC. ONC are positive for cell surface markers N-CAM, PSA-N-CAM, neutral endopeptidase, N-aminopeptidase, NGF low-affinity receptor homologue (CD40), and transferrin receptor by flow cytometry for the intermediate filament proteins peripherin, vimentin, and NF-H by immunocytochemistry. Responses to neurotrophic factors measured were process outgrowth, cytoskeletal protein expression, and protein phosphorylation. Process outgrowth was increased by interleukin-beta 164-171 (IL-1beta) or by the combination of IL-1beta, interleukin-6 (IL-6), nerve growth factor (NGF), and basic fibroblast growth factor (bFGF). This combination of IL-1beta, IL-6, NGF, and bFGF (16NF) increased expression of two cytoskeletal proteins, NF-H protein and microtubule-associated protein tau. Application of the individual neurotrophic factors IL-1beta, IL-6, NGF, and bFGF increased protein phosphorylation, while 16NF produced an immediate increase in tyrosine phosphorylation of several proteins (MW of 40-80, 120, 150, and 190 kDa). The 16NF combination appears to act through a tyrosine-kinase-mediated pathway to induce process extension and increase NF-H expression. The ONC culture has the potential to be further explored to examine the relationship among process outgrowth, protein phosphorylation, and synergy between neurotrophin and cytokine receptor systems. 相似文献
835.
836.
D Rapaport KP Künkele M Dembowski U Ahting FE Nargang W Neupert R Lill 《Canadian Metallurgical Quarterly》1998,18(9):5256-5262
Translocation of preproteins across the mitochondrial outer membrane is mediated by the TOM complex. This complex consists of receptor components for the initial contact with preproteins at the mitochondrial surface and membrane-embedded proteins which promote transport and form the translocation pore. In order to understand the interplay between the translocating preprotein and the constituents of the TOM complex, we analyzed the dynamics of the TOM complex of Neurospora crassa and Saccharomyces cerevisiae mitochondria by following the structural alterations of the essential pore component Tom40 during the translocation of preproteins. Tom40 exists in a homo-oligomeric assembly and dynamically interacts with Tom6. The Tom40 assembly is influenced by a block of negatively charged amino acid residues in the cytosolic domain of Tom22, indicating a cross-talk between preprotein receptors and the translocation pore. Preprotein binding to specific sites on either side of the outer membrane (cis and trans sites) induces distinct structural alterations of Tom40. To a large extent, these changes are mediated by interaction with the mitochondrial targeting sequence. We propose that such targeting sequence-induced adaptations are a critical feature of translocases in order to facilitate the movement of preproteins across cellular membranes. 相似文献
837.
A Etchegaray R Dieckmann J Kennedy G Turner H von D?hren 《Canadian Metallurgical Quarterly》1997,237(1):166-169
A 51-year-old woman developed an acute onset of renal dysfunction accompanied by rash, lumbar pain, arthralgias, fever, eosinophiluria, and an elevated serum creatinine after 6 days of intravenous piperacillin-tazobactam therapy. On discontinuing piperacillin-tazobactam and after a 21-day course of prednisone, the patient's constitutional symptoms dissipated and her renal function returned to baseline. Acute interstitial nephritis has been reported as an adverse effect of many drugs, including antibiotics, but not, to our knowledge, after piperacillin-tazobactam. The time course of events suggested that piperacillin-tazobactam was the cause of acute interstitial nephritis in this patient. 相似文献
838.
V Shusterman B Aysin V Gottipaty R Weiss S Brode D Schwartzman KP Anderson 《Canadian Metallurgical Quarterly》1998,32(7):1891-1899
OBJECTIVES: We hypothesized that neurohormonal activity contributes to the initiation of sustained ventricular tachycardia (VT) as reflected in indices of heart rate variability (HRV). BACKGROUND: Autonomic nervous system activity participates in experimental arrhythmias but clinical studies have been inconsistent. METHODS: Holter electrocardiograms from 53 patients with VT were analyzed. Heart rate variability indices were determined over 5 and 15 min and 24 h and examined for changes before the onset of VT. Heart rate variability indices in the frequency domain included ultra low frequency power (FP) (ULFP): 0-0.0033 Hz; very low FP (VLFP): 0.0033-0.04 Hz; low FP (LFP): 0.04-0.15 Hz; high FP (HFP): 0.15-0.4 Hz; total power (TP); normalized LFP (LFPn); normalized HFP (HFPn), and the ratio: LFP/HFP. RESULTS: Heart rate variability indices were severely diminished: TP: 12,009+/-11,076 ms2; ULFP: 10,087+/-9,565 ms2; VLFP: 1,416+/-1,571 ms2; LFP: 544+/-620 ms2; HFP: 161+/-176 ms2, and LFP/HFP: 3.68+/-2.83. Heart rate increased before VT (80.4+/-17.3 to 85.3+/-17.4 bpm, p < 0.001). Several HRV variables declined 30 min before VT compared to 24-h values (VLFP: -5.89+/-17.81%, p = 0.031; LFP: -5.23+/-14.3%, p = 0.003; HFP: -4.35+/-13.7%, p = 0.04). LFPn and the LFP/HFP ratio decreased significantly before the onset of VT (-17.7+/-46.9%, p = 0.035 and -8.24+/-38.8%, p = 0.037, respectively), whereas HFPn increased slightly (4.29+/-29.9%, p = 0.097). CONCLUSIONS: Heart rate rose, whereas LFP, LFPn and LFP/HFP fell before the onset of VT. This pattern of changes could be explained by a rise in sympathetic activity and saturation of the HRV signal resulting in dissociation of the average and rhythmical effects of sympathetic activity. These findings suggest that alterations in autonomic activity contributed to arrhythmogenesis in this group of patients. 相似文献
839.
The purpose of this study was to explore the clinical impact of child sex abuse on bulimic patients. Specifically, differences in treatment response and preliminary treatment outcome between hospitalized bulimic patients with and without a reported history of sexual abuse were examined. The patients were evaluated for past history of alleged sexual abuse by investigator-based interview and ratings of severity of sexual abuse were made. Assessments of mood, eating disordered-related attitudes, and eating behaviors were conducted at the start of treatment, weekly during treatment, and three months post discharge. Sixty-one per cent (45) of the 74 patients enrolled in the study reported a history of child sexual abuse. The majority of such events constituted serious and very serious abuse by this study's criteria. The abused subjects exhibited higher levels of depression, anxiety, and eating disordered attitudes at each assessment point relative to nonabused subjects. In addition, abused subjects were more likely to be re-hospitalized in the 3 month post-discharge period. Significant differences in the extent of actual bulimic behaviors were not detected. Both the abused and nonabused bulimic patients demonstrated significant reductions in psychiatric symptomatology from pretreatment to posttreatment, and from posttreatment to follow-up. Contrary to prediction, differences in symptomatology between the very serious, serious, and least serious abused groups were not detected. Results suggest that bulimic patients with reported histories of sexual abuse can be effectively engaged in a conventional eating disorder treatment program, but that such abuse may place patients at a disadvantage owing to higher levels of pretreatment symptom severity. Findings suggest that extended and/or more specific intervention may be warranted for the abused bulimic patient. 相似文献
840.
RL Walker TL de Peralta MR Villanueva KP Snipes JE Madigan DW Hird RW Kasten 《Canadian Metallurgical Quarterly》1995,43(2-3):143-150
Isolates of Salmonella choleraesuis serotype ohio (S. ohio) recovered during an outbreak of equine neonatal salmonellosis on a Thoroughbred farm were compared with isolates of the same serotype from various animal, feed and environmental sources. Biochemical profiles, antimicrobial susceptibility patterns, phage susceptibility, plasmid profiles, restriction endonuclease analysis and ribotyping were used to compare relatedness of the strains. A total of 46 outbreak and non-outbreak associated isolates of S. ohio were studied. Differences in antimicrobial susceptibility patterns, phage susceptibility and plasmid profiles were useful for differentiating outbreak isolates from other equine isolates as well as bovine, porcine and some poultry isolates. Feed and other poultry isolates, most in geographic proximity to the outbreak, were indistinguishable from outbreak isolates by any of the methods employed. Investigative studies on the farm along with results of genotypic and phenotypic analysis of isolates suggested that contaminated feed was the most likely source of Salmonella in this outbreak. 相似文献