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排序方式: 共有2274条查询结果,搜索用时 15 毫秒
71.
FLOOR E JANSEN AAG JENNEKENS-SCHINKEL AN HUFFELEN WM CEES VAN VEELEN AN RIJEN WILLEM CJ ALPHERTS JAN VERMEULEN ONNO VAN NIEUWENHUIZEN 《European journal of paediatric neurology》2002,6(6):315-320
Localization of vital components of neurological functioning has to be performed before epilepsy surgery can be considered in children with intractable epilepsy. This study reports the experience with the Wada procedure in very young children and/or developmentally delayed children with an a priori considerable chance of failing the procedure. The aim of this study was to indicate the applicability of this procedure in this patient group. The Wada procedure is described in 16 children under 10 years of age and/or have intelligence quotient scores below 50 and/or are critically ill and/or are behaviourally disturbed. Information on motor, language and memory functioning is obtained in respectively 13/15, 9/13, and 5/11 children. Nine children underwent epilepsy surgery without postoperative impairment of neurological functioning. In five children epilepsy surgery was not performed because of the results of the Wada procedure or the lack of information during the Wada procedure. One child became seizure-free before surgery. Even in very young, developmentally delayed or behaviourally disturbed children, the Wada test can provide important information with respect to the decision pro or contra epilepsy surgery. 相似文献
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Brain and platelet serotonin transporter in humans-correlation between [123I]-ADAM SPECT and serotonergic measurements in platelets 总被引:3,自引:0,他引:3
Uebelhack R Franke L Herold N Plotkin M Amthauer H Felix R 《Neuroscience letters》2006,406(3):153-158
Blood platelets are thought to be a useful peripheral model for investigating the central serotoninergic mechanisms associated with the serotonin transporter (SERT). On the other hand, an in vivo investigation of SERT in the human brain has been made possible by the development of several promising SPECT radioligands, such as [123I]-ADAM. The aim of the present study was to investigate the possible correlation between the SERT measurements in the brain and those in platelets. Forty-four subjects (14 healthy subjects and 30 patients with the diagnosis of major depression or schizoaffective disorder) were examined. The [123I]-ADAM binding was assessed 4h after injection using MR-guided regions of interest (ROIs) in the midbrain and cerebellum. In a parallel investigation, serotonin (5HT) concentration and kinetic characteristics of 5HT uptake activity (Vmax and Km) were determined in platelet-rich plasma. Overall, there was no significant correlation between the V(max) of 5HT uptake in platelets and the specific to nonspecific partition coefficient of [123I]-ADAM (V'3) in the midbrain. However, low but significant Pearson correlation coefficients were found for V(max) and normalised activities measured in the midbrain (r=0.310, p=0.043). The correlation was stronger and significant in females (n=20, r=0.629, p=0.003) but low and non-significant in the 24 males (r=0.104). Although confirmation is necessary, it seems that the relationship between different indices of [123I]-ADAM binding in the brain and 5HT uptake characteristics in platelets is complex, nonuniform, and possibly gender-specific. 相似文献
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CJ Stewart ECL Marrs S Magorrian A Nelson C Lanyon JD Perry ND Embleton SP Cummings JE Berrington 《Acta paediatrica (Oslo, Norway : 1992)》2012,101(11):1121-1127
Aim: To describe gut colonization in preterm infants using standard culture and 16S gene rRNA profiling, exploring differences in healthy infants and those who developed NEC/late onset sepsis (LOS). Methods: Ninety‐nine stools from 38 infants of median 27‐week gestation were cultured; 44 stools from 27 infants had their microbial profiles determined by 16S. Ordination analyses explored effects of patient variables on gut communities. Results: Standard microbiological culture identified a mean of two organisms (range 0–7), DGGE 12 (range 3–18) per patient. Enterococcus faecalis and coagulase negative staphylococci (CONS) were most common by culture (40% and 39% of specimens). Meconium was not sterile. No fungi were cultured. Bacterial community structures in infants with NEC and LOS differed from healthy infants. Infants who developed NEC carried more CONS (45% vs 30%) and less Enterococcus faecalis (31% vs 57%). 16S identified Enterobacter and Staphylococcus presence associated with NEC/LOS, respectively. Conclusions: Important differences were found in the gut microbiota of preterm infants who develop NEC/LOS. The relationship of these changes to current practices in neonatal intensive care requires further exploration. 相似文献
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Close correlation of copy number aberrations detected by next‐generation sequencing with results from routine cytogenetics in acute myeloid leukemia 下载免费PDF全文
Sebastian Vosberg Tobias Herold Luise Hartmann Martin Neumann Sabrina Opatz Klaus H. Metzeler Stephanie Schneider Alexander Graf Stefan Krebs Helmut Blum Claudia D. Baldus Wolfgang Hiddemann Karsten Spiekermann Stefan K. Bohlander Ulrich Mansmann Philipp A. Greif 《Genes, chromosomes & cancer》2016,55(7):553-567
High throughput sequencing approaches, including the analysis of exomes or gene panels, are widely used and established to detect tumor‐specific sequence variants such as point mutations or small insertions/deletions. Beyond single nucleotide resolution, sequencing data also contain information on changes in sequence coverage between samples and thus allow the detection of somatic copy number alterations (CNAs) representing gain or loss of genomic material in tumor cells arising from aneuploidy, amplifications, or deletions. To test the feasibility of CNA detection in sequencing data we analyzed the exomes of 25 paired leukemia/remission samples from acute myeloid leukemia (AML) patients with well‐defined chromosomal aberrations, detected by conventional chromosomal analysis and/or molecular cytogenetics assays. Thereby, we were able to confirm chromosomal aberrations including trisomies, monosomies, and partial chromosomal deletions in 20 out of 25 samples. Comparison of CNA detection using exome, custom gene panel, and SNP array analysis showed equivalent results in five patients with variable clone size. Gene panel analysis of AML samples without matched germline control samples resulted in confirmation of cytogenetic findings in 18 out of 22 cases. In all cases with discordant findings, small clone size (<33%) was limiting for CNA detection. We detected CNAs consistent with cytogenetics in 83% of AML samples including highly correlated clone size estimation (R = 0.85), while six out of 65 cytogenetically normal AML samples exhibited CNAs apparently missed by routine cytogenetics. Overall, our results show that high throughput targeted sequencing data can be reliably used to detect copy number changes in the dominant AML clone. © 2016 Wiley Periodicals, Inc. 相似文献
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KI Wheeler GM Schmölzer CJ Morley PG Davis 《Acta paediatrica (Oslo, Norway : 1992)》2011,100(1):67-70
Background: Ventilator frequency is one of the determinants of tidal volume delivery during high‐frequency ventilation. Clinicians increasingly use data on ventilator displays to inform their decisions. Aim: To measure the frequencies delivered by the Dräger Babylog 8000plus ventilator when used in high‐frequency mode. Methods: Ventilator waveforms using a test lung were recorded at the full range of settings 5–20 Hz using Spectra software at 1000 Hz. The changes in frequency produced by a 1‐ Hz change in set frequency were calculated. Actual and displayed frequencies were compared. Results: For settings up to 12 Hz, median (range) difference between set and delivered frequencies was 0 (?0.4 to +0.1) Hz. Above 12 Hz, delivered frequency varied by ?0.3 (?1.9 to +0.3) Hz. For 1‐ Hz changes in frequency settings, in the range 5–12 Hz, 1‐ Hz changes produced a change in delivered frequency of 1.0 (0.6–1.4) Hz. Above 12 Hz, the corresponding changes were 0.7 (0–2.9) Hz. The ventilator displays the set frequency during operation rather than the delivered frequency. Conclusion: At 12 Hz and below, the differences between set and delivered frequencies were relatively small compared with those at 13 Hz and higher. Above 13 Hz, the difference between set and delivered frequencies was up to 2.9 Hz. Some frequency setting changes did not result in a change in delivered frequency. 相似文献