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1.
Following exposure of CHO-K1 cells to 137Cs irradiation at doses up to 20Gy, a delay in G2 was observed to occur in cells permitted to divide normally, while cells induced to become giants by means of cytochalasin B demonstrated a minimal delay in the transition 2C-8C suggesting that the inhibition of cytokinesis results in modification of one or more cell cycle checkpoints. We postulate that this may occur as a consequence of damage tolerance, or by a feedback loop resulting from the reorganisation of the cytoskeleton that precludes cytokinesis.  相似文献   

2.
Patients with unilateral temporal epileptic foci were contrasted with normal subjects and patients with neuromuscular disorders in the evaluation of specific psychosocial aspects of behavior. Eighteen traits were assessed in equivalent questionnaires completed by both subjects and observers. The epileptic patients self-reported a distinctive profile of humorless sobriety, dependence, and obsessionalism; raters discriminated temporal lobe epileptics on the basis of circumstantiality, philosophical interests, and anger. The right temporal epileptic displayed emotional tendencies in contrast to ideational traits of left temporal epileptic. Right temporal epileptics exhibited "denial," while left temporal epileptics demonstrated a "catastrophic" overemphasis of dissocial behavior. The results support the hypotheses that sensory-affective associations are established within the temporal lobes, and that, in man, there exists a hemispheric asymmetry in the expression of affect.  相似文献   

3.
SPECT scanning with Tc99mHM-PAO was performed on 40 children with 'intractable' partial epilepsy; 27 patients had abnormalities on SPECT images consisting of areas of decreased cerebral blood flow. In 18 of these 27 subjects there was a good correlation between site of the abnormalities on SPECT scan and interictal EEG foci. 12 patients with regionally decreased CBF had also neuroimaging (C.T. and/or R.M.I.) abnormalities. The brain SPECT provides more precise detection of epileptogenic foci, when used to complement EEG, also in childhood-onset epilepsy.  相似文献   

4.
OBJECTIVE: To compare the antibiotic susceptibility of bacterial isolates from patients in the surgical intensive care unit (SICU) with hospital-wide bacterial susceptibility. DESIGN: Retrospective cohort analytic study. SETTING: Eight-bed SICU in a university-affiliated teaching hospital. PATIENTS: All hospitalized patients with culture results positive for microorganisms. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Antibiotic susceptibility data were collected retrospectively for all bacterial isolates from SICU patients during July 1, 1994, to June 30, 1995. All duplicate and surveillance cultures were eliminated from the data set. Susceptibility testing was conducted using our standard laboratory methods. Results were compared with the hospital-wide antibiogram (HWA) for the same time period. Comparisons were made using the chi(2) test with Yates correction or the Fisher exact test, as appropriate. Staphylococcus aureus (HWA, n=494; SICU, n=71) was significantly less susceptible to oxacillin (51% vs 28%; P<.001), ciprofloxacin (50% vs 25%; P<.001), erythromycin (46% vs 23%; P<.001), and clindamycin (51% vs 27%; P<.001) in the SICU. Coagulase-negative staphylococci (HWA, n=339; SICU, n=37) were significantly less susceptible to oxacillin (33% vs 16%; P=.04) and clindamycin (57% vs 34%; P=.02). Pseudomonas aeruginosa (HWA, n=513; SICU, n=96) was less susceptible to imipenem (85% vs 74%, P=.01) and more susceptible to ticarcillin-clavulanic acid (88% vs 100%, P<.001) in the SICU. Escherichia coli (HWA, n=474; SICU, n=36) was more susceptible to most penicillin-derivative antibiotics in the SICU (ampicillin [68% vs 83%, P=.06], ticarcillin [65% vs 86%, P=.01], mezlocillin [76% vs 95%, P=.01], and ticarcillin-clavulanic acid [88% vs 100%, P=.02]). CONCLUSIONS: The 2 most commonly isolated bacterial pathogens in the SICU (S aureus and P aeruginosa) had significantly different susceptibility patterns compared with the HWA. Surprisingly, E coli isolated in the SICU tended to be more susceptible to penicillin-derivative antibiotics. These data indicate that empiric antibiotic choices in the SICU may be better guided by unit-specific antibiograms.  相似文献   

5.
OBJECTIVE: The aim was to investigate the feasibility of recording the electrical auditory brain stem response (EABR) evoked by electrical stimulation at the promontory (Prom-EABR) as a tool to assist selection of the ear for cochlear implantation in young children. STUDY DESIGN: The study group consisted of young children for whom the decision to proceed with implantation with the Nucleus mini 22-channel cochlear implant (Cochlear (UK) Ltd., London, UK) had already been made. SETTING: The Prom-EABR was recorded after the children had been anesthetised, but before the start of surgery. PATIENTS: A group of 25 children (11 boys and 14 girls), whose age at implantation ranged from 2 years 11 months to 6 years 8 months (mean age, 4 years 5 months), were investigated. INTERVENTION: Recordings of the Prom-EABR were used to determine which ear would receive the cochlear implant, providing there were no preexisting contraindications regarding selection of the ear. MAIN OUTCOME MEASURE: It has been suggested from earlier studies that the characteristics of the amplitude input/output (I/O) function of the EABR are related to neuronal survival. If the ear with the "better" I/O function is chosen for implantation, it might be expected that these children will perform better on average than those in whom the ear has been selected at random. RESULTS: Reliable recordings of the Prom-EABR were achieved in 40 ears (80%) of the 50 ears in the study. In 20 of the 25 children the technique was actively employed for selection of the ear for implantation. CONCLUSIONS: Recording of the Prom-EABR in the operating theater is a viable technique. Future analysis of long-term outcome measures of performance with the implant will confirm or dispute the benefit of ear selection using the Prom-EABR.  相似文献   

6.
Traditional T2-based imaging techniques are geared toward imaging long-T2 species. Traditional techniques are, therefore, not optimal in clinical situations where the information of interest lies in the short-T2 species. T2-selective RF excitation (TELEX) is a technique for obtaining a T2-based contrast that highlights short-T2 values while suppressing long-T2 values-opposite to traditional T2 contrast. Previously, TELEX has been demonstrated qualitatively to highlight only very short-T2 values (T2 approximately 0.001 s). When applied to longer T2 values (T2 > or = 0.01 s), TELEX becomes sensitive to deltaB0 non-uniformities. This restricts its application to problems in which the T2 of interest is very short. In this study, TELEX is characterized quantitatively. Furthermore, a bandwidth broadening scheme is developed that reduces the deltaB0 sensitivity of TELEX. This permits the technique to be applied to longer T2 values. The capabilities and limitations of a practical implementation of TELEX are discussed.  相似文献   

7.
Identification of epileptogenic foci in patients with refractory epilepsy remains a significant diagnostic challenge. Magnetic resonance imaging studies frequently fail to reveal an anatomic origin for the seizures, and scalp electroencephalography is often limited to identification of the involved hemisphere. Functional imaging modalities such as PET and SPECT are more promising tools for this application because they reflect the functional pathology associated with the seizure. These changes are more pronounced ictally, but until recently, no radiopharmaceutical was available that could be used routinely for ictal SPECT. The present study was therefore undertaken to determine whether 99mTc-bicisate could be used in ictal SPECT in pediatric patients with refractory epilepsy, to compare the patterns of ictal and interictal blood flow in these patients and to compare the localization information provided by ictal SPECT with that available from other techniques. METHODS: Technetium-99m-bicisate/SPECT was compared prospectively with scalp EEG for its ability to identify a possible seizure focus in pediatric patients with refractory epilepsy. Ictal and interictal SPECT studies were performed in 10 patients (3-19 yr old, mean age 10.9 +/- 4.3 yr; 7 female, 3 male) in whom MRI scans revealed no lesions that might be responsible for the seizures. RESULTS: Ictal SPECT was performed in all patients, and all ictal studies revealed focal perfusion abnormalities. By comparison, four of the interictal SPECT studies showed regional hypoperfusion that corresponded to the regions of hyperperfusion in the ictal studies, and three showed regional hyperperfusion corresponding to the hyperperfused regions in the ictal studies. Three interictal studies revealed no abnormal perfusion. Scalp EEG provided localization information in five patients. CONCLUSION: These initial results suggest that ictal SPECT with 99mTc-bicisate is a more promising tool for the identification of epileptogenic foci than interictal SPECT or scalp EEG in patients without focal abnormalities on MRI.  相似文献   

8.
9.
The effect of short-term discontinuation of antiepileptic drugs (AEDs) on spectral analysis of EEG background activity (spectral EEG) was studied in patients undergoing preoperative evaluation for epilepsy surgery. We also wished to clarify whether AED discontinuation would provide lateralizing evidence in spectral EEGs of patients with temporal lobe epilepsy (TLE). Spectral EEGs were performed in 15 patients receiving their regular medication regimen and again after a 1-week period during AED withdrawal. A subgroup of 9 patients who had previously undergone temporal lobectomies (TLE group) was studied separately. In this group, we evaluated the effect of preceding seizures on spectral EEG derived from temporal neocortical areas. In all patients, spectral EEG changes were detected even after a short-term AED withdrawal. The total amount of absolute delta activity was reduced and occipital peak frequency and relative alpha activity were increased as compared with baseline values. In TLE patients with habitual seizures occurring < 20 h before the spectral EEG recording, lateralization was correctly identified by the greater amount of absolute delta activity ipsilateral to the epileptogenic focus. Epileptic seizures are accompanied by subtle focal slowing in spectral EEG for a much longer period than has been assumed. In addition, postictal spectral EEG over the temporal lobes may have lateralizing value. Further studies in larger numbers of patients are needed to evaluate the role of spectral EEG in the preoperative evaluation of patients for temporal lobe surgery.  相似文献   

10.
Single photon emission tomography (SPECT) was performed in 27 patients with refractory complex partial seizures from the temporal lobes due to mesial temporal sclerosis. Independent blinded observers assessed the 28 interictal studies and 9 ictal/postictal studies. Visual analysis of interictal studies detected hypoperfusion in 22, ipsilateral to the epileptogenic zone in 19 (67%) and contralateral in 3 (10.7%). Quantified temporal lobe asymmetry, greater than a previously derived normal range, correctly identified the epileptogenic zone in 16 (61.5%) with false lateralization in 4 (15.3%). In all 9 cases in which they were performed, ictal/postictal studies showed hyperperfusion at the region of epileptic focus. In 3 patients with complex partial seizures followed by symmetric generalized tonic-clonic seizures, hyperperfusion restricted to the temporal lobe was demonstrated. In 5 of these patients the interical studies were unable to demonstrate localized changes. There were no significant correlations between SPECT findings and clinical parameters or EEG slowing in the temporal lobes.  相似文献   

11.
Thirty per cent of the iodine in thyroglobulin is present as iodothyronines. L-thyroxine (T4) represents 90-95% of hormonal iodine, 3,5,3'-triodo-L-thyronine (T3) contains at the most two per cent of it, 3,3'5'-triodo-L-thyronine (rT3) even less, as well as traces of 3,3'-diodo-L-thyronine. The plasma concentration of T4 is about 8 microgram per 100 ml, in the case of T3 it is 120 ng and 25 ng for rT3. The cell nucleus preferentially binds T3 and rT3 and there are also some specific mitochondrial proteins which possess a high affinity for T3. L-thyroxine is dehalogenated peripherically to T3, to take care of most of the requirements in T3. The enrichment of the plasma in rT3 has been shown to occur under various experimental and pathological conditoins. The blood level of T3 varies in inverse ratio to the level of rT3 and it shows that the peripheral formation of one is compensated for by the other. The excess of the prehormone T4 is metabolised as 3,5,3',5'-tetraiodothyroacetic acid (TetrAc); its level in the blood varies in the same way as the level of T3, in particular it decreases during starvation.  相似文献   

12.
13.
INTRODUCTION: Only the organic and cryptogenic forms of frontal lobe epilepsy have been admitted by the ILAE, but according to several reports in the literature, it probably exists also an idiopathic form, at present not well recognized. OBJECTIVE: To study the differences between the organic and the cryptogenic forms of frontal epilepsy in our patients, that might indicate the presence of idiopathic cases within the presumed cryptogenic group. MATERIAL AND METHODS: All patients diagnosed of frontal lobe epilepsy, EEG registered, at the neuropediatric clinic of our hospital during 1993-1996, were selected: 30 patients under 14 years of age that were classified as organic (10 cases) or cryptogenic (20 cases) according to CT or MRI findings. The Mann-Whitney test and the Fisher exact test were performed for statistical analysis. Five patients with peculiar neurocognitive symptoms, epilepsy-related, are described in detail. RESULTS: Significative differences between the organic and cryptogenic forms of frontal lobe epilepsy were not found except for the tendency of cryptogenic EEG foci to spread beyond the frontal lobe, to generalize and to be associated with foci of other localizations. Epileptic status, either convulsive or not convulsive, were a frequent complication in both groups. CONCLUSIONS: The identification of an idiopathic form of frontal lobe epilepsy is difficult by its low prevalence as compared to the cryptogenic and organic forms, by the tendency of frontal seizures to become epileptic status, which predicts an intractable epilepsy, and by the clinical characteristics essential to frontal discharges: heterogeneity, frequent impairment of consciousness and specially the neurocognitive semiology, including dementia, that occurs as a critic or paracritic phenomenon, and that sometimes may develop or be accentuated by antiepileptic medication.  相似文献   

14.
The goals of this study were to determine (1) the yield of magnetoencephalography (MEG) according to epilepsy type, (2) if MEG spike sources colocalize with focal epileptogenic pathology, and (3) if MEG can identify the epileptogenic zone when scalp ictal electroencephalogram (EEG) or magnetic resonance imaging (MRI) fail to localize it. Twenty-two patients with mesial temporal (10 patients), neocortical temporal (3 patients), and extratemporal lobe epilepsy (9 patients) were studied. A 37-channel biomagnetometer was used for simultaneously recording MEG with EEG. During the typical 2-3-hour MEG recording session, interictal epileptiform activity was observed in 16 of 22 patients. MEG localization yield was greater in patients with neocortical epilepsy (92%) than in those with mesial temporal lobe epilepsy (50%). In 5 of 6 patients with focal epileptogenic pathology, MEG spike sources were colocalized with the lesions. In 11 of 12 patients with nonlocalizing (ambiguous abnormalities or normal) MRI, MEG spike sources were localized in the region of the epileptogenic zone as ultimately defined by all clinical and EEG information (including intracranial EEG). In conclusion, MEG can reliably localize sources of spike discharges in patients with temporal and extratemporal lobe epilepsy. MEG sometimes provides noninvasive localization data that are not otherwise available with MRI or conventional scalp ictal EEG.  相似文献   

15.
Manual ventilation (MAV) or handbagging is a frequent and often life-saving procedure for neonates; however, few studies allow for an objective evaluation of techniques or possible risks. We compared parameters of ventilation and pulmonary mechanics obtained during routine pressure-limited MAV to those obtained during spontaneous breathing (SPB) in the same infant at approximately the same time. We selected 20 preterm neonates in the recovery phase of respiratory distress syndrome who received periodic MAV and were capable of optimum spontaneous minute ventilation (> 300 mL/kg/min). During MAV compared to SPB we measured higher tidal volume (8.1 +/- 0.5 SE vs. 5.4 +/- 0.4 SE mL/kg, P < 0.001), lower total pulmonary compliance (0.65 +/- 0.05 vs. 1.16 +/- 0.11 SE mL/cmH2O, P < 0.001), end-inspiratory compliance, higher pulmonary resistance (121 +/- 11 vs. 61 +/- 7 SE cmH2O/L/s, P < 0.001) and higher peak inspiratory airflow (2.8 +/- 0.2 vs. 1.6 +/- 0.1 L/s, P < 0.001). Inspiratory time (Ti) was consistently longer during MAV (0.49 +/- 0.02 vs. 0.36 +/- 0.02 SE, P < 0.001) such that during MAV the difference between actual Ti and minimal effective Ti (fivefold inspiratory time constant) was larger (0.29 +/- 0.03 vs. 0.13 +/- 0.03 s, P < 0.05). Our study suggests that operator-dependent ventilatory variables such as tidal volume, inspiratory time, frequency, and airflow need to be further evaluated in order to develop standardized guidelines for the safe administration of MAV. Until then the ventilator used for brief or augmented ventilatory support is a reasonable alternative to administering MAV by inconsistent standards.  相似文献   

16.
We examined the influences of attachment orientations on within-person changes in affect as a function of perceptions of the interaction partner's agreeable behavior in interactions involving a romantic partner and other kinds of partners. Working adults reported affect, perceptions of the other person's behavior, and the relationship with the other in interpersonal events during 20 days. As expected, the within-person association between perceived partner's agreeable behavior and negative affect was stronger for individuals higher on attachment anxiety and was weaker for individuals higher on attachment avoidance. These effects were more pronounced in interactions with a romantic partner than with other persons. Findings demonstrate that attachment orientations are associated with differing within-person processes and that these processes are sensitive to kind of interaction partner. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

17.
PURPOSE: This study was undertaken to determine what changes, if any, occur in the electroencephalogram (EEG) and in neuropsychological test findings of adults with medically intractable complex partial epilepsy over a 10-year period. METHODS: We studied 35 adults, with a mean age of 32 years (range, 16-59 years) at time of initial testing. We compared the distribution of epileptiform patterns documented on the initial pair of waking and sleeping EEGs to those observed on another pair obtained 10 years later. During this same 10-year period, we also examined changes in the Wechsler Adult Intelligence Scale (WAIS) and on the tests from the Neuropsychological Battery for Epilepsy. RESULTS: The EEGs of 28 (80%) of patients at the tenth year were identical to those seen initially. Five (14%) of patients demonstrated EEGs after 10 years with either no discharges or only unilateral discharges, where bilateral discharges were seen a decade earlier. Only two (6%) of patients had EEGs at the tenth year that showed bilateral discharges where only unilateral discharges were seen originally. We found no general change in intelligence or neuropsychological functioning after 10 years, although a few subtle losses were noted on several neuropsychological measures. CONCLUSIONS: For most adults with medically intractable complex partial epilepsy, the EEG and neuropsychological test scores remain reasonably stable over a decade.  相似文献   

18.
Self-reported emotional experience does not differ between patients with schizophrenia and healthy individuals, suggesting that the anhedonia in schizophrenia instead reflects decoupling of affect from motivated behavior. In 2 behavioral conditions, participants with schizophrenia and healthy participants were able to prolong or decrease exposure to stimuli while stimuli were present or alter the likelihood of future exposure to stimuli on the basis of internal representations. They also provided self-reports of affective experience. Patients showed weaker correspondence between behavior and ratings than did comparison participants. The effect was amplified when patients responded on the basis of internal rather than evoked stimulus representations. These data suggest that the motivational deficits in schizophrenia reflect problems in the ability to translate experience into action. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

19.
We performed interictal FDG-PET- and MRI-based hippocampal volumetric measurements on 18 adult patients with complex partial epilepsy of temporal lobe origin in whom we had identified their ictal focus by video-telemetry EEG. Sixteen patients (89%) had regional hypometabolism, 11 (61%) had focal 1.5-tesla T2-weighted MRI (two structural abnormalities, nine hippocampal formation [HF] increased T2 signal), and nine (50%) had absolute HF atrophy ipsilateral to the temporal ictal focus. Ten (55%) had abnormal L/R HF ratios, nine ipsilateral to the EEG focus. All patients with abnormal MRI volumetric studies had focal PET abnormalities. Only seven had both abnormal HF volume ratios and T2 MRI (all increased HF T2 signal). There was a significant correlation between hippocampal volume and inferior mesial and lateral temporal lobe cerebral metabolic rate of glucose asymmetry index (p < 0.01), suggesting that hypometabolism may reflect hippocampal atrophy. PET is more sensitive than MRI volumetry in identifying the ictal focus but does not provide additional information when HF atrophy is present.  相似文献   

20.
Examined whether (1) loudness is a necessary component of the technique of voice control (i.e., the use of loud commands in response to disruptive behavior) in pediatric dentistry, (2) voice control actually reduces children's disruptive behavior, and (3) children's negative affect increases after treatment. Ss were 40 3.5–7 yr old children who were scheduled for cavity restoration. Ss were assigned randomly to either loud- or normal-voice groups and were classified as potentially disruptive or not, based on an initial screening. Prior to and after treatment, Ss reported their feelings, and disruptive behavior was scored. Following loud- but not normal-voice commands, Ss reduced their disruptive behavior. After treatment, Ss who received loud- but not normal-voice commands tended to report less arousal and more pleasure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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