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OBJECTIVE: Left prefrontal transcranial magnetic stimulation has been reported to have ECT-like effects in depression; therefore, the authors planned a study of transcranial magnetic stimulation in mania. METHOD: Sixteen patients completed a 14-day double-blind, controlled trial of right versus left prefrontal transcranial magnetic stimulation at 20 Hz (2-second duration per train, 20 trains/day for 10 treatment days). Mania was evaluated with the Mania Scale, the Brief Psychiatric Rating Scale, and the Clinical Global Impression. RESULTS: Significantly more improvement was observed in patients treated with right than with left prefrontal transcranial magnetic stimulation. CONCLUSIONS: The therapeutic effect of transcranial magnetic stimulation in mania may show laterality opposite to its effect in depression.  相似文献   

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Animals engage in a startlingly diverse array of behaviours that depend critically on the time of day or the ability to time short intervals. Timing intervals on the scale of many hours to around a day is mediated by the circadian timing system, while in the range of seconds to hours a different system, known as interval timing, is used. Recent research has illuminated some of the neural mechanisms underlying the 'internal clocks' of these two different timing systems in both animals and humans. Therapeutic applications for humans with impairments in either timing system may ultimately result from these endeavours.  相似文献   

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The aim of the present study was to trace early intracellular changes induced in effector and target cells during their conjugation. This was performed by monitoring the intracellular fluorescein fluorescence polarization (IFFP), using the Cellscan apparatus. This apparatus permits the repetitive spectroscopic measurement of individual selected live cells within a population of many cells, while the location of each cell is known and preserved during the various cell manipulations and/or their suspending medium. Both natural killer (NK) and lymphocyte activated killer (LAK) cells were used as effector cells, while NK-sensitive K562 and NK-resistant Daudi cell lines were used as targets. In this study kinetic IFFP measurements were carried out for a period of approximately 4 h following cell attachment. Within minutes following effector-target conjugation, transient reduction of IFFP was observed consecutively, first in the effector and then in the target cells. A continuous reduction of IFFP occurring only in target cells was also found 50 min following conjugation. No reduction in IFFP was observed using NK- and LAK-resistant target cells. Good correlation was found between early stages of conjugation, as assessed by IFFP, and cytolytic efficiency as assessed by 51chromium release assay. When NK-resistant and LAK-resistant target cells were used, no reduction of IFFP was observed.  相似文献   

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OBJECTIVE: To evaluate stereotactic transcranial magnetic stimulation (TMS) as a tool for presurgical functional mapping of human motor cortex. METHODS: Transcranial magnetic stimulation using a frameless stereotactic system was performed in two patients with tumors near the central sulcus. TMS motor function maps were plotted on the patients' three-dimensional volumetric magnetic resonance imaging data and compared with direct electrical cortical stimulation at surgery with the patient under local anesthesia. RESULTS: Stereotactic TMS was well tolerated by both patients and was consistent with known somatotopic representation of human motor cortex. The results demonstrated a good correlation between the TMS and electrical cortical stimulation maps, with all TMS responses eliciting more than 75% of the maximum motor evoked potential falling within 1 cm of the electrical cortical stimulation site. CONCLUSIONS: Our findings indicate that stereotactic TMS is feasible and can provide accurate noninvasive localization of cortical motor function. It may prove to be a useful method for presurgical planning.  相似文献   

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When infants first learn to reach at about 4 months, their hand paths are jerky and tortuous, but their reaches become smoother and straighter over the first year. Here the authors consider the role of the underlying limb dynamics, which scale with movement speed, on the development of trajectory control. The authors observed 4 infants weekly and then biweekly from reach onset to 1 yr. Improvements in trajectories were not linear, but showed plateaus and regressions in straightness and smoothness. When infants' nonreaching movements were fast, their reaches were also fast, and faster reaches were also less straight. This is consistent with an equilibrium trajectory form of control, where development involves the increasing ability to stabilize the trajectory against self-generated movement perturbations. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

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唐钢1号高炉开炉及快速达产实践   总被引:1,自引:0,他引:1  
对唐钢1号高炉扩容大修改造、开炉及快速达产经验进行了总结。唐钢1号高炉经过精心的开炉准备和合理的开炉方案制订,在开炉7天内利用系数突破2.0,10天开始喷煤富氧,15天煤比达70kg/t,实现了快速开炉快速达产。  相似文献   

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We report results from a patient in whom we obtained converging evidence from positron emission tomography (PET) and intraoperative stimulation mapping to support a one-way dissociation between the functional areas involved in word repetition and synonym generation. Intraoperative stimulation mapping interfered with synonym generation but did not disturb word repetition at the same left inferior frontal site at which a cerebral blood flow (CBF) increase had been observed for a synonym generation task. The results for this single subject suggest that the functional areas involved in different aspects of linguistic processing are dissociable and that specific disruption under conditions of cortical stimulation can be correlated with the brain regions identified via PET as the most active during performance of a specific task.  相似文献   

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包钢4号高炉于1995年11月14日建成投产,有效容积为2 200m3.2003年2月22日停炉中修,2003年3月31日22:58点火送风,经过精心操作,合理调剂,第8天利用系数即达到2.023 t/(m3·d).  相似文献   

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BACKGROUND AND PURPOSE: The wide application of embolization in the treatment of aneurysms has created the need for an intraprocedural means to anticipate a poor outcome by monitoring hemodynamic changes in the brain. METHODS: Transcranial Doppler sonography was used to monitor flow velocity in the middle cerebral artery (MCA) in 23 patients undergoing embolization with Guglielmi detachable coils (GDCs) of either incidental or symptomatic intracranial aneurysms. Sonographic values were recorded from the ipsilateral MCA at the beginning, middle, and end of the interventional procedure and 24 hours afterward. RESULTS: No complications occurred in 15 patients. In these cases, sonography showed an average decrease in MCA flow velocity of 2.7% after GDC application, returning to baseline at the end of treatment and then increasing by about 17% 24 hours later. In four patients with vasospasm on posttreatment angiograms, MCA flow velocity increased to values higher than 120 cm/s after GDC application, returning to baseline after 24 hours. In four patients with ischemic complications (two transient ischemic attacks, one stroke, one vascular death), MCA flow velocity decreased more than 30% and did not return to preoperative values within 24 hours. CONCLUSION: The application of transcranial Doppler sonographic monitoring during endovascular treatment may help to identify patients at risk for posttreatment cerebral ischemia.  相似文献   

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INTRODUCTION/OBJECTIVE: The introduction of the technique of magnetic stimulation for the study of motor disorders has led to a better understanding of the pathophysiological mechanisms involved in amyotrophic lateral sclerosis (ALS). MATERIAL AND METHODS: Thirty two patients with ALS were studied in order to describe the behaviour of the variables: central conduction time (CCT), amplitude ratio (Ar) and motor threshold (MT) evaluated by means of motor evoked potentials (MEP). RESULTS: Analysis of these variables showed the great sensitivity of MEP for the detection of abnormalities in the corticospinal tract with 95% of the results being abnormal. Subclinical abnormalities were detected in 22.4% of recordings. Axonal degeneration was the commonest kind of conduction disorder seen. A significant lineal relationship between the evolution time and the variables MT, Ar and CCT (p < 0.05) was demonstrated. This suggests that there is a progressive deterioration of the voluntary motor pathway which begins with an excitotoxic mechanism at the onset of the disease and ends with the death of motor neurones. CONCLUSIONS: The electrophysiological results discussed, together with observations on isolated cases provide evidence in favour of the hypothesis of degeneration of the upper motor neurone. Although it is recognized that this alone does not explain the whole degenerative phenomenon of the motor system which occurs in ALS.  相似文献   

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The clinical, electrophysiological and haemodynamic effects of precentral gyrus stimulation (PGS) as a treatment of refractory post-stroke pain were studied in 2 patients. The first patient had a right hemibody pain secondary to a left parietal infarct sparing the thalamus, while the second patient had left lower limb pain developed after a right mesencephalic infarct. In both cases, spontaneous pain was associated with hyperpathia, allodynia and hypoaesthesia in the painful territory involving both lemniscal and extra-lemniscal sensory modalities in patient 1, extra-lemniscal sensory modality only in patient 2. Both patients were treated with electrical PGS by means of a 4-pole electrode, the central sulcus being per-operatively located using the phase-reversal of the N20 wave of somatosensory evoked potentials. No sensory side effect, abnormal movement or epileptic seizure were observed during PGS. The analgesic effects were somatotopically distributed according to the localization of electrode on motor cortex. A satisfactory long-lasting pain control (60-70% on visual analog scale) as well as attenuation of nociceptive reflexes were obtained during PGS in the first patient. Pain relief was less marked and only transient (2 months) in patient 2, in spite of a similar operative procedure. In this patient, in whom PGS eventually evoked painful dysethesiae, no attenuation of nociceptive RIII reflex could be evidenced during PGS. Cerebral blood flow (CBF) was studied using emission tomography (PET) with O-labeled water. The sites of CBF increase during PGS were the same in both patients, namely the thalamus ipsilateral to PGS, cingulate gyrus, orbito-frontal cortex and brainstem. CBF increase in brainstem structures was greater and lasted longer in patient 1 while patient 2 showed a greater CBF increase in orbito-frontal and cingular regions. Our results suggest that PGS-induced analgesia is somatotopically mediated and does not require the integrity of somatosensory cortex and lemniscal system. PGS analgesic efficacy may be mainly related to increased synaptic activity in the thalamus and brainstem while changes in cingulate gyrus and orbito-frontal cortex may be rather related to attentional and/or emotional processes. The inhibitory control on pain would involve thalamic and/or brainstem relays on descending pathways down to the spinal cord segments, leading to a depression of nociceptive reflexes. Painful dysesthesiae during stimulation have to be distinguished from other innocuous sensory side effects, since they may compromise PGS efficacy.  相似文献   

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Area and depth penetration of transcranial stimulation methods such as transcranial electrical stimulation (TES) are poorly defined. We investigated the feasibility of a simultaneous TES and fMRI measurement. The aim was to compare the signal intensity changes measured using BOLD fMRI during sequential finger movement with the signal response during artificial transcranial stimulation. Tes induced contralateral finger contractions and in T2* weighted images a transient signal increase was observed in the area underlying the electrodes. Compared with the signal obtained during sequential finger movements, the area activated by TES was more localized, signal amplitude, was smaller and there was no post-stimulus undershoot. These data indicate that TES induces a local blood flow increase associated with a drop in the concentration of deoxyhaemoglobin.  相似文献   

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Tn10, like several other transposons, exhibits a marked preference for integration into particular target sequences. Such sequences are referred to as integration hotspots and have been used to define a consensus target site in Tn10 transposition. We demonstrate that a Tn10 hotspot called HisG1, which was identified originally in vivo, also functions as an integration hotspot in vitro in a reaction where the HisG1 sequence is present on a short DNA oligomer. We use this in vitro system to define factors which are important for the capture of the HisG1 target site. We demonstrate that although divalent metal ions are not essential for HisG1 target capture, they greatly facilitate capture of a mutated HisG1 site. Analysis of catalytic transposase mutants further demonstrates that the DDE motif plays a critical role in 'divalent metal ion-dependent' target capture. Analysis of two other classes of transposase mutants, Exc+ Int- (which carry out transposon excision but not integration) and ATS (altered target specificity), demonstrates that while a particular ATS transposase binds HisG1 mutants better than wild-type transposase, Exc+ Int- mutants are defective in HisG1 capture, further defining the properties of these classes of mutants. Possible mechanisms for the above observations are considered.  相似文献   

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