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61.
Stojanov PL Savic DV Zivkovic MB Calovic ZR 《Pacing and clinical electrophysiology : PACE》2008,31(9):1100-1107
Background: The aim of the study was to analyze endovenous pacing lead survival in pediatric population implanted by cephalic cut down, or by axillary vein puncture.
Methods: All implantations were performed in total endotracheal anesthesia, by the same surgeon. Implantations of ventricular leads were performed by cephalic vein cut down or by external jugular vein preparation. In dual-chamber pacing, atrial leads were implanted via cephalic vein (along with ventricular lead), by axillary vein puncture or via external jugular vein. All implanted leads were secured by resorbable suture.
Results: Over the 20-year follow-up period, 105 children of 5.7 years average age (range 1 day–15 years) were implanted with a permanent endovenous pacing system for congenital or postsurgical complete atrioventricular block or sinus node disease. Within the group, 27 patients (25.7%) weighed less than 10 kg on implantation. A total of 121 endovenous leads were implanted. All ventricular leads were with a passive fixation mechanism, and most of them unipolar (87.6%) and steroid eluting (94.2%). Leads implanted in atrial position were 82% bipolar, predominantly with active fixation (94%), and all steroid eluting. The most frequently used mode of stimulation was VVIR (66.6%). No acute or chronic lead displacement, exit block, sensing problem, lead conductor fracture, insulation defect or infections were observed during the total follow-up of 709 pacing years (average 6.9, range 0–20 years).
Conclusion: Implantation of the endovenous leads by preparation of the cephalic or puncture of the axillary vein, with lead fixation by resorbable suture represents a method of choice. 相似文献
Methods: All implantations were performed in total endotracheal anesthesia, by the same surgeon. Implantations of ventricular leads were performed by cephalic vein cut down or by external jugular vein preparation. In dual-chamber pacing, atrial leads were implanted via cephalic vein (along with ventricular lead), by axillary vein puncture or via external jugular vein. All implanted leads were secured by resorbable suture.
Results: Over the 20-year follow-up period, 105 children of 5.7 years average age (range 1 day–15 years) were implanted with a permanent endovenous pacing system for congenital or postsurgical complete atrioventricular block or sinus node disease. Within the group, 27 patients (25.7%) weighed less than 10 kg on implantation. A total of 121 endovenous leads were implanted. All ventricular leads were with a passive fixation mechanism, and most of them unipolar (87.6%) and steroid eluting (94.2%). Leads implanted in atrial position were 82% bipolar, predominantly with active fixation (94%), and all steroid eluting. The most frequently used mode of stimulation was VVIR (66.6%). No acute or chronic lead displacement, exit block, sensing problem, lead conductor fracture, insulation defect or infections were observed during the total follow-up of 709 pacing years (average 6.9, range 0–20 years).
Conclusion: Implantation of the endovenous leads by preparation of the cephalic or puncture of the axillary vein, with lead fixation by resorbable suture represents a method of choice. 相似文献
62.
Parallel input makes the brain run faster 总被引:1,自引:0,他引:1
Raij T Karhu J Kicić D Lioumis P Julkunen P Lin FH Ahveninen J Ilmoniemi RJ Mäkelä JP Hämäläinen M Rosen BR Belliveau JW 《NeuroImage》2008,40(4):1792-1797
In serial sensory processing, information flows from the thalamus via primary sensory cortices to higher-order association areas. However, association cortices also receive, albeit weak, direct thalamocortical sensory inputs of unknown function. For example, while information proceeds from primary (SI) to secondary (SII) somatosensory cortex in a serial fashion, both areas are known to receive direct thalamocortical sensory input. The present study examines the potential roles of such parallel input arrangements. The subjects were presented with median nerve somatosensory stimuli with the instruction to respond with the contralateral hand. The locations and time courses of the activated brain areas were first identified with magnetoencephalography (MEG). In a subsequent session, these brain areas were modulated with single-pulse transcranial magnetic stimulation (TMS) at 15-210 ms after the somatosensory stimulus while electroencephalography (EEG) was recorded. TMS pulses at 15-40 ms post-stimulus significantly speeded up reaction times and somatosensory-evoked responses, with largest facilitatory effects when the TMS pulse was given to contralateral SII at about 20 ms. To explain the results, we propose that the early somatosensory-evoked physiological SII activation exerts an SII-->SI influence that facilitates the reciprocal SI-->SII pathway - with TMS to SII we apparently amplified this mechanism. The results suggest that the human brain may utilize parallel inputs to facilitate long-distance cortico-cortical connections, resulting in accelerated processing and speeded reaction times. This arrangement could also allow very early top-down modulation of the bottom-up stream of sensory information. 相似文献
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66.
Lei Zhang Yun Wang Jingjing Sun Hongye Ma Cheng Guo 《Pathology, research and practice》2019,215(9):152515
Long non-coding RNAs (lncRNAs) have been identified as crucial regulators in the tumorigenesis and progression of hepatocellular carcinoma (HCC). Recently, long intergenic non-protein coding RNA 205 (LINC00205) has been identified as a prognostic biomarker in HCC. However, the biological role of LINC0205 and its potential molecular mechanism are poorly investigated. Here, we found that the expression of LINC00205 was dramatically up-regulated in HCC tissues compared to adjacent nontumor tissues. Furthermore, the level of LINC00205 in both Hep3B and Huh7 cells was prominently higher than that in normal hepatic cell line LO2. Notably, the high expression of LINC00205 was strongly correlated with tumor size ≥5 cm, venous infiltration and advanced tumor stages. Functionally, LINC00205 knockdown obviously repressed the proliferation, migration and invasion of Hep3B and Huh7 cells in vitro. An inverse correlation between LINC00205 and miR-122-5p was detected in HCC tissues. Interestingly, LINC00205 knockdown increased the level of miR-122-5p in both Hep3B and Huh7 cells. Mechanistically, luciferase reporter assay demonstrated LINC00205 acted as a competing endogenous RNA (ceRNA) by directly interacting with miR-122-5p. More importantly, miR-122-5p overexpression significantly restrained the proliferation, migration and invasion of HCC cells. Collectively, our study provides solid evidence to support the oncogenic role of LINC00205 in HCC, which may be benefit for the improvement of HCC therapy. 相似文献
67.
BackgroundIn 2020 the coronavirus disease 19 (COVID-19) pandemic imposed a total and sudden lockdown. We aimed to investigate the consequences of the first COVID-19 lockdown (mid-March – mid-April 2020) on motor and non-motor symptoms (NMS) in a cohort of French people with Parkinson's disease (PwP).MethodsPwP were enrolled either by an on-line survey sent from the national France Parkinson association (FP) to reach the French community of PwP or as part of outpatients' telemedicine visits followed by an hospital-based Parkinson Expert Center (PEC). All patients were evaluated using the same standardized questionnaire assessing motor and NMS (including a list of most disabling, new or worsened symptoms and Patient's Global Impression-Improvement scales [PGI-I]) psycho-social queries and quality of life.Results2653 PwP were included: 441 (16.6%) in the PEC group and 2122 (83.4%) in the community-based group. Physiotherapy was interrupted among 88.6% of the patients. 40.9% referred a clinical modification of their symptoms. Based on the questionnaire, pain (9.3%), rigidity (9.1%) and tremor (8.5%) were the three most frequently new or worsened reported symptoms. Based on the PGI-I, the motor symptoms were the most affected domain, followed by pain and psychic state. PwP in community-based group tended to have more frequent worsening for motor symptoms, motor complications, pain and confusion than those of the PEC group.ConclusionsThe first COVID-19 lockdown had a negative impact on motor and NMS of PwP. Efforts should be allocated to avoid interruption of care, including physiotherapy and physical activities and implement telemedicine. . 相似文献
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69.
Roohollah Massoudi Marc M. Van Wanrooij Sigrid M. C. I. Van Wetter Huib Versnel A. John Van Opstal 《The European journal of neuroscience》2014,39(9):1538-1550
We characterised task‐related top‐down signals in monkey auditory cortex cells by comparing single‐unit activity during passive sound exposure with neuronal activity during a predictable and unpredictable reaction‐time task for a variety of spectral‐temporally modulated broadband sounds. Although animals were not trained to attend to particular spectral or temporal sound modulations, their reaction times demonstrated clear acoustic spectral‐temporal sensitivity for unpredictable modulation onsets. Interestingly, this sensitivity was absent for predictable trials with fast manual responses, but re‐emerged for the slower reactions in these trials. Our analysis of neural activity patterns revealed a task‐related dynamic modulation of auditory cortex neurons that was locked to the animal's reaction time, but invariant to the spectral and temporal acoustic modulations. This finding suggests dissociation between acoustic and behavioral signals at the single‐unit level. We further demonstrated that single‐unit activity during task execution can be described by a multiplicative gain modulation of acoustic‐evoked activity and a task‐related top‐down signal, rather than by linear summation of these signals. 相似文献
70.
L. Hippolyte K. Iglesias M. Van der Linden K. Barisnikov 《Journal of intellectual disability research : JIDR》2010,54(8):714-726
Background Although the prevalence of mental illness and behaviour problems is lower in adults with Down syndrome (DS) than in other populations with intellectual disabilities, they do present emotional and relational problems, as well as social integration difficulties. However, studies reporting on specific competences known to be central in developing appropriate social relationships (e.g. social reasoning, emotion processing, theory of mind) remain rare in the adult DS population and the mechanisms underlying these people's emotional and relational difficulties are unclear. Method The present study investigated the ability to understand the appropriateness of others' social behaviour in 34 adults with DS, using the Social Resolution Task (SRT). Their results were compared with those of 34 typically developing (TD) children matched for gender and receptive vocabulary. The relationships among the SRT experimental task, cognitive competences (receptive and productive vocabulary, non‐verbal reasoning, inhibition, selective attention) and a caregiver‐rated measure of socio‐emotional behaviour were examined in the DS group. Results The DS participants' global SRT scores did not differ from those of the controls. However, analyses of the SRT subscores revealed that the DS group identified significantly fewer inappropriate situations than the control group. Nevertheless, when they correctly identified the behaviour as inappropriate, they were as well as the controls to explain the rules underlying their responses. Regression analyses showed that receptive vocabulary and selective attention and a specific dimension of the socio‐emotional profile (social relating skills) constituted the best predictors of the DS adults' performance on the SRT. Conclusions The main findings show that the DS participants demonstrate relatively good social reasoning skills in comparison with TD children matched for verbal age. However, the two groups present distinctions in their response patterns, and the influence of cognitive variables on success on the SRT also appears different. While selective attention skills are found to be significant predictors for both groups, the influence of receptive vocabulary level is much stronger in the DS group. The implications of particular cognitive and socio‐emotional factors for success on the SRT in this group are considered in more detail. 相似文献