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41.
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   
42.
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   
43.
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   
44.
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   
45.
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   
46.
Research on gambling demonstrates that youths are involved in gambling activities. As they take part in these activities, young people develop and maintain irrational thoughts about gambling and become at risk for developing severe gambling problems. In a previous study, a French video was designed specifically to correct misconceptions and increase knowledge about gambling (Ferland, Ladouceur, & Vitaro, 2002). Findings indicated that the video significantly improves subjects' knowledge about gambling and corrects their misconceptions. The present study aims to evaluate the effectiveness of the English version of that video. The sample comprised 506 grade 7 and 8 English speaking students from Canada. The results confirmed the efficacy of the video in increasing knowledge of gambling and correcting misconceptions concerning the outcome of these games. The implications of these results for the prevention of gambling problems are discussed.  相似文献   
47.
目的 探讨隐匿抑郁症患者的脑电变化特点.方法 经神经内科门诊筛查选择86例以躯体化症状为主诉的隐匿抑郁症患者作为观察组,另设65例健康体检者作为正常对照组,两组均行脑电图、脑干听觉诱发电位和视觉诱发电位检查.结果 观察组脑电图异常率63.95%,正常对照组异常率仅为13.85%,两组比较有显著性差异(P<0.05).观察组脑电图以轻度异常为主,局限性异常多见于额叶,诱发电位以各主波及波间潜伏期较正常对照组显著性延长.结论 以躯体化障碍为主诉的抑郁症患者其脑电图异常率明显高于正常人,且诱发电位潜伏期延长.  相似文献   
48.
研制开发病房大楼手术摄像、内窥镜、电子显微镜、病理图像等医学声像信号与科教(培训交流)中心、阶梯教室、示教室、主任办公室等终端医学声像信号的实时双向同步传输示教系统,以弥补PACS系统单向、帧传、滞后的缺陷.为大型学术交流、现场教学示教观摩提供技术支持。  相似文献   
49.
SQL Server2000数据库与VC++6.0软件平台的医用手术显微镜视频专家系统,通过专业医用视频图像采集卡将显微镜视频信号引入计算机,实现手术图像的采集、显示;同时,病历管理系统对采集图像进行编辑、处理、管理、并自动生成病人电子病历,可打印图文兼备的报告单,它可与任何手术显微镜配套使用,实现显微镜手术和病灶诊断2种功能。  相似文献   
50.
West syndrome is a distinct, infantile onset, epileptic encephalopathy, associated with poor neurodevelopmental outcome. The present study was designed as a randomized, open-label, pilot study to evaluate the safety, feasibility, and effectiveness of oral zonisamide therapy in comparison with adrenocorticotropic hormone therapy in infants with West syndrome. Thirty infants with West syndrome were randomized to receive treatment with either synthetic, intramuscular adrenocorticotropic hormone (30–60 IU) or oral zonisamide (4–25 mg/kg/day). The study participants had a long treatment lag and preponderance of male sex (90%). The primary effectiveness outcome measure was the cessation of epileptic spasms at 2 weeks of initiation of therapy and persistent till 6 weeks as per West Delphi consensus statement recommendations. Comparison of efficacies of zonisamide versus adrenocorticotropic hormone was as following: the cessation of epileptic spasms (27% vs. 40%, p = 0.70), resolution of hypsarrhythmia at 14 days (20% vs. 33%, p = 0.68) and resolution of hypsarrhythmia at 6 weeks (36% vs. 71%, p = 0.14). Overall, the study observed a poor efficacy of both adrenocorticotropic hormone and zonisamide therapy, which is probably due to long treatment lag and a high proportion of structural aetiology. However, oral zonisamide appeared to be safe and tolerable in the study.  相似文献   
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