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2.
Veena Kumari Jeffrey A. Gray Philip J. Corr Owen F. Mulligan Paul A. Cotter Stuart A. Checkley 《Psychopharmacology》1997,129(3):271-276
The effects of an indirect dopamine-agonist, d-amphetamine, and a non-selective dopamine receptor antagonist, haloperidol, were investigated in normal male volunteers using
a between-subjects double-blind design in a procedural learning task, thought mainly to involve unconscious/automatic learning.
The results showed: (1) d-amphetamine facilitated response speed, whereas haloperidol inhibited it, in comparison to placebo; (2) the linear increase
in procedural learning corresponded with pharmacological manipulation of degree of dopaminergic activity, i.e. subjects given
haloperidol showed the least, and subjects given d-amphetamine the greatest, procedural learning. The implications of these findings are discussed in relation to investigation
of abnormalities of procedural learning processes in schizophrenia.
Received: 28 June 1996/Final version: 2 October 1996 相似文献
3.
The effect of lithium on slow wave sleep (SWS) was studied in ten normal male volunteers using home based cassette sleep recording and automatic sleep stage analysis. Lithium increased SWS, an effect consisten with a reduction in brain 5-HT2 receptor function. 相似文献
4.
本文设计的8模型血压自适应控制系统,试用于造成失血休克模型的家兔的血压自控治疗,22只休克家兔中18只能控制血压于预置水平。根据血压控制期间药物输注速率变化规律,可将22只家兔分为三类,剂量上升型、剂量下降型和迟钝型。实验表明多模型血压自适应控制系统应用于失血性休克家兔的血压控制治疗是可行的,能做到剂量个体化,按需给药。在血压控制期间显示的药物输注速率变化能在一定程度上反映机体休克状况,有可能为及 相似文献
5.
6.
Huupponen E Himanen SL Hasan J Värri A 《Medical & biological engineering & computing》2003,41(6):727-732
A fully automatic method to analyse electro-encephalogram (EEG) sleep spindle frequency evolution during the night was developed
and tested. Twenty allnight recordings were studied from ten healthy control subjects and ten sleep apnoea patients. A total
of 22 868 spindles were detected. The overall mean spindle frequency was significantly higher in the control subjects than
in the apnoea patients (12.5Hz against 11.7Hz, respectively; p<0.004). The proposed method further identified the sleep depth
cycles, and the mean spindle frequency was automatically determined inside each sleep depth cycle. In control subjects, the
mean spindle frequency increased from 12.0Hz in the first sleep depth cycle to 12.6Hz in the fifth cycle. No such increase
was observed in the sleep apnoea patients. This difference in the spindle frequency evolution was statistically significant
(p<0.004). The advantage of the method is that no EEG amplitude thresholds are needed. 相似文献
7.
白细胞图像自动识别系统的研究 总被引:2,自引:0,他引:2
我们所用的图像分割方法是在对图像距离变换的基础上,综合区域和边界方法,充分利用图像中包含的信息,实现白细胞图像的分割。根据细胞的形状、纹理、颜色等的特点选取并测定22个特征值,用统计分类的方法设计分类器。通过对560幅图像共831个细胞的测试表明,此系统的识别正确率为96%,经临床专家评估,本系统运用模式识别技术对外周血中的白细胞图像实现自动识别,具有较好的实用价值。 相似文献
8.
评价新型的双极和三极导管自动心室除颤系统电除颤对左心室收缩和舒张功能的影响。动物麻醉后,在X光机指导下,分别在10只犬心脏内装置双极导管自动除颤系统(组Ⅰ);在10只猪心脏内装置三极导管自动除颤系统(组Ⅱ);并行电除颤试验。使用食管超声心动图在电除颤前后记录二维、M型和多谱勒超声图像。组I动物接受4次电除颤,电量为64J;组Ⅱ接受平均8次电除颤,电量为210J。结果显示:左室收缩面积分数、左室等容舒张时间和二尖瓣血流E波与A波速度比值以及时间-流速积分比值等反映左室舒缩功能的指标在两组动物除颤后均无显著改变。研究表明:两种经静脉导管自动心室除颤系统中反复低能量心内膜电除颤对左室舒缩功能无明显损伤作用;研究结果为经静脉多极导管自动心室除颤系统在临床的应用和电生理研究提供了可靠的实验数据。 相似文献
9.
Arámbula Cosío F Márquez Flores JA Padilla Castañeda MA Solano S Tato P 《Medical & biological engineering & computing》2005,43(5):672-677
An automatic colour image segmentation and cell counting software system has been developed for immunocytochemical analysis
of stained tissue samples. The system was designed to count the total number of positive and negative cells in tissue samples
treated with cytokine DNA probes from pigs naturally parasitised with Taenia solium metacestodes, using in situ hybridisation.
A reaction index was calculated as the ratio of the number of cells with a positive reaction to the total number of cells
(positives plus negatives) for each of five different probes. The objectives of automatic counting were to improve the reproducibility
of the analysis and reduce the processing time of large image batches. A fast KNN classifier was used for colour segmentation.
Watershed segmentation combined with edge detection was used to isolate individual cells that were then automatically labelled,
using the results of the corresponding colour segmented image. Validation was performed on 122 non-training digital images
with a total of 1069 positive cells and 1459 negative cells, with the following results: a mean true positive rate of 90.2%
for positive cells and a mean true positive rate of 85.4% for negative cells. The corresponding mean false positive rates
were 9.6% and 6.6%. The mean reaction index error of the automatic analysis was 5.35%. The processing of each digital image
took 10 s on a Pentium IV PC. 相似文献
10.
Claes Lundsteen Beth Bjerregaard Erik Granum John Philip Kim Philip 《Clinical genetics》1980,17(3):183-190