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11.
抑郁症的睡眠脑电图与人脑兴奋守恒假说 总被引:1,自引:0,他引:1
目的 探索抑郁症状与睡眠脑电图参数的相关性。方法 对 18例抑郁症和 10例正常人评定汉密尔顿抑郁评定量表 (HAMD)和检测睡眠脑电图。结果 HAMD总分与觉醒次数及REM密度分别呈显著正相关 (r分别等于 0 .4 0 8和 0 .4 4 5 ,P均 <0 .0 5 )。结论 抑郁症和正常人的白天中枢抑制与夜间中枢兴奋相关 ,从而支持人脑兴奋守恒假说。 相似文献
12.
Deborah G Murdoch Eaton David Wertheim Rowena Oozeer Lilly MS Dubowitz Victor Dubowitz 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(5):486-492
Murdoch Eaton DG, Wertheim D, Oozeer R, Dubowitz LMS, Dubowitz V. Reversible changes in cerebral activity associated with acidosis in preterm neonates. Acta Paediatr 1994;83:486–92. Stockholm. ISSN 0803–5253
Computerized online EEG monitoring in ventilated preterm infants less than 32 weeks' gestation enabled evaluation of the effect of acidosis on cerebral function. All episodes of acidosis were found to be associated with changes in the levels of cerebral activity. In 21 of the 32 episodes, EEG activity returned to pre-acidosis levels after therapeutic intervention. The duration of EEG abnormality was related to the severity of acidosis. However, the time to recovery of the EEG after therapeutic procedures was not related to duration of the EEG change. 相似文献
Computerized online EEG monitoring in ventilated preterm infants less than 32 weeks' gestation enabled evaluation of the effect of acidosis on cerebral function. All episodes of acidosis were found to be associated with changes in the levels of cerebral activity. In 21 of the 32 episodes, EEG activity returned to pre-acidosis levels after therapeutic intervention. The duration of EEG abnormality was related to the severity of acidosis. However, the time to recovery of the EEG after therapeutic procedures was not related to duration of the EEG change. 相似文献
13.
Lars Ohlson 《Neurourology and urodynamics》1988,7(4):365-376
This study was undertaken to determine the nature of pressure changes in manometric studies of renal pelvis and calyces. In previous studies in pigs it has been assumed that pressure increases occur in the contracting segments of the renal pelvis and calyces, but our observations suggested that these increases were actually due to distension of noncontracted segments. Pressures were recorded with two catheters introduced percutaneously into the pyelocalyceal system with simultaneous video recording of the fluoroscopic image. There was no pressure rise in the calyces or the renal pelvis when these segments contracted; however, pressure rose when the noncontracted calyces were distended by a remote contraction ring. These findings confirmed the observations at kinetic urography. They agreed with the hydrodynamic experience that the pressure in a ring-shaped contracted segment is lower than upstream and downstream of that segment. It was concluded that if the porcine pyelocalyceal system is a valid model of the human, the pressure increases, assumed to be contractions, were actually caused by the injection and distension of the noncontracted segments. 相似文献
14.
We have developed a new in vitro method of quantitatively analyzing ciliary movement in the ependymal wall of the aqueduct in rats. An axial slice of the midbrain containing ependymal wall was placed in a culture dish filled with a culture medium containing latex beads 1 m in diameter at a concentration of 107 beads/ml. The movement of the beads caused by flow of culture medium generated by the to-and-fro ciliary movement was recorded by a high speed video system attached to an inverted phase-contrast microscope. Ciliary movement was expressed by the speed of the latex beads (m/s). Aqueductal ciliary movement in congenitally hydrocephalic HTX rats, congenitally hydrocephalic WIC-Hyd rats, and other normal rats was evaluated. The results suggest that in congenitally hydrocephalic WIC-Hyd rats the degree of hydrocephalus related strongly to the degree of ciliary dyskinesia, but in congenitally hydrocephalic HTX rats it did not. Considering this discrepancy, we attempted to see whether or not hydrocephalus was caused by artificial disturbance of ependymal ciliary movement in vivo. We found that continuous infusion of metavana date, an inhibitor of ciliary movement, into the III ventricle of normal Sprague-Dawley rats for 7 days induced dilatation of the ventricular system. Although the question whether or not disturbance of aqueductal ependymal ciliary movement is related to the development of human congenital hydrocephalus is debatable, the results of the present in vitro and in vivo experimental investigations appear to suggest that the disturbance of ciliary movement in the aqueduct could at least be one of the factors contributing to the inducement of hydrocephalus in experimental conditions. 相似文献
15.
N H Barmack 《Experimental neurology》1978,59(2):304-321
Studies of bilateral hemispheric somatosensory evoked potentials (SEP) were carried out on 17 comatose patients following closed-head injury. Control evoked potentials were obtained from 74 normal volunteers. A prognosis of potential recovery or nonrecovery from coma was made in all 17 patients based on the SEP analyses. All subjects underwent bilateral median and peroneal nerve stimulation and responses were averaged from scalp electrodes placed over the somatotopic sensory cortex for the wrist and leg. The prognostic outcome of all 17 patients was accurately predicted following SEP analysis. Results show that 4 of 17 patients with prognoses of “positive recovery” had eight defined SEP peaks present within a time base analysis of 300 ms. Twelve patients with prognoses of “negative recovery” had five or less SEP peaks present within a time base of 500 ms. The majority of the “negative recovery” patients showed only SEP primary waveform components consisting of two peaks. The data suggest a potentially useful method using SEP analysis to prognosticate the possible recovery from clinical coma. 相似文献
16.
The case of a patient with reappearing stupor, accompanied by auditory hallucinations and persecutory ideas during the periods and not with alternating excitement, is reported. After 24 years of neuroleptics medication with little effect, the lithium carbonate regimen was started, which showed a remarkable prophylactic effect. The implications of lithium carbonate treatment for recurrent psychosis are discussed. 相似文献
17.
To determine spindle activity during sleep in congenitally blind subjects, electroencephalogram sleep recordings were done on two or three consecutive nights in five subjects aged in their 20s and 30s. The number per minute and the duration of sleep spindles, scored visually, were compared with the data of sighted persons of comparable ages. The results indicated that the total number of sleep spindles a night was ranged from 117 to 585, and the number per minute ranged 0.52 to 2.06 during stage 2. Both values were much less than the values of sighted persons. 相似文献
18.
M.J. Edel P.D. Robbins J.M. Papadimitriou M.F. D'Antuono J.M. Harvey C.A. Mitchel H.J.S. Dawkins 《Breast cancer research and treatment》1998,47(1):17-27
Case-control methodology was used to evaluate the significance of vascularity in small breast carcinomas with regard to the presence or absence of axillary lymph node metastases. Vascularity was assessed in 32 axillary node positive primary breast tumours (LN+ve) less than 2 cm in size and compared with 56 control axillary node negative primary tumours (LN–ve), which were matched for histological type and grade and tumour size. This study design employed computer-assisted video analysis (CAVA) to assess the total blood vessel perimeter (BVP), total blood vessel area (BVA), and total blood vessel density (BVD) throughout a tissue section that encompassed an entire cross section of the tumour and its immediate periphery. The BVA and BVD in these tumours were not significantly different between LN+ve and LN–ve groups. The LN–ve carcinomas had, on average, a significantly (P < 0.05) higher total BVP (3355 µm/mm2) than LN+ve tumours (2771 µm/mm2). 'Hot spot' areas were also independently assessed by two pathologists and the same areas measured by CAVA. A strong correlation (P < 0.001) between the two methods of assessment of BVD of the neovascular 'hot spots' was found; however, no association with axillary lymph node metastasis was found using either method of assessment. In conclusion, vascularity assessed by either blood vessel density or blood vessel size in primary invasive breast cancers less than 2 cm in diameter showed no association with axillary lymph node metastasis; in fact a negative association was found with total BVP of whole tumour sections and BVD in 'hot spots' using CAVA. Further, this study has established a computer-assisted method of quantifying vascularity in solid neoplasms and is a positive step towards a standardised approach to this diverse and methodologically variable area. 相似文献
19.
20.
Granular materials are widespread in nature and human production, and their macro-mechanical behavior is significantly affected by granule movement. The development of computer vision has brought some new ideas for measuring the numerical information (including the amount of translation, the rotation angle, velocity, acceleration, etc.) of dynamic granular materials. In this paper, we propose a numerical measurement method for dynamic granular materials based on computer vision. Firstly, an improved video instance segmentation (VIS) network is introduced to perform end-to-end multi-task learning, and its temporal feature fusion module and tracking head with long-sequence external memory can improve the problems of poor video data quality and high similarity in appearance of granular materials, respectively. Secondly, the numerical information can be extracted through a series of post-processing steps. Finally, the effectiveness of the measurement method is verified by comparing the numerical measurement results with the real values. The experimental results indicate that our improved VIS obtains an average precision (AP) of 76.6, the relative errors and standard deviations are maintained at a low level, and this method can effectively be used to measure the numerical information of dynamic granular materials. This study provides an intelligent proposal for the task of measuring numerical information of dynamic granular materials, which is of great significance for studying the spatial distribution, motion mode and macro-mechanical behavior of granular materials. 相似文献