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91.
福建省鼠伤寒沙门氏菌病原学特征变迁趋势   总被引:1,自引:0,他引:1  
目的:了解福建省鼠伤寒沙门氏菌的病原学特征变迁情况。方法:采用噬菌体分型、质粒谱分析及耐药性测定的方法,对福建省1980~1995年15年鼠伤寒沙门氏菌的病原学特征进行动态监测。结果:福建省鼠伤寒沙门氏菌的噬菌体流行型别存在明显的变迁与更迭;质粒谱型有逐渐增多且分散趋势;菌株耐药率逐年大幅度上升,耐药谱逐年迅速增宽,多重耐药菌株逐年急剧增多,耐药现象日趋严重。结论:噬菌体分型、质粒谱分析及耐药性测定是监测福建省鼠伤寒沙门氏菌病原学特征变迁趋势的有效方法。  相似文献   
92.
此专家系统在修善顾博士行医经验和治疗原则的基础上 ,利用多媒体技术 ,结合声频、视频、图片和文本以治疗乳腺增生病。在医疗设计中 ,着重于顾博士的类型识别要点和乳腺增生病的自然规律。尤其 ,此医疗设计阐明了顾博士所总结的有价值的治疗经验 ,以突出此专家系统的科学性、实用性和可操作性。笔者曾将此专家系统应用于临床 1 30份病例的治疗中。其结果表明此专家系统的临床治疗正确率与顾博士临床治疗相对照达 98%。  相似文献   
93.
Short time delays change pattern induced flicker colors (PIFCs)   总被引:1,自引:0,他引:1  
Subjects decided on whether the colors of the rings on a modified Benham's top were the same or different. The cause of color differences was a variable time delay. Δt, of the black and white stimulus pattern on the disc. Time delays of Δt = 50 μsec and less caused detectable changes in color and brightness.  相似文献   
94.
Summary Plasma-levels of thioridazine, mesoridazine, sulphoridazine and two other metabolites were determined in ten older chronic psychotic patients on thioridazine therapy. The plasma-level before the morning dose of thioridazine was the most reliable parameter for clinical studies. An intra-individual relationship between lower doses of thioridazine and plasma-levels was found. The percentage contribution of psychoactive compounds to the total sum of thioridazine plus metabolites ranged from 43–74%. The mean early disappearance half-life of thioridazine was 5 hours, and its mean late disapperance half-life was 26 hours.  相似文献   
95.
Scale-invariant superiority of foveal vision in perceptual categorization   总被引:1,自引:0,他引:1  
The recognition of objects is exceedingly difficult in indirect view. This complication cannot be explained in terms of retino-cortical magnification, as size scaling fails to establish position invariance both for character recognition [Strasburger, H. & Rentschler, I. (1996) Eur. J. Neurosci., 8 1787-1791] and pattern classification [Jüttner, M. & Rentschler, I. (1996) Vision Res., 36, 1007-1021]. Thus we compared, for two tasks of discrimination learning and category learning with respect to a common set of grey-level patterns, how humans perform in foveal and extrafoveal vision. Observers learnt to discriminate (size-scaled) images equally well in foveal and extrafoveal view, whereas they displayed profound deficiencies in extrafoveal category learning for the same patterns. From the behavioural learning data, internal representations of the learning signals were reconstructed by means of computer simulations. For foveal view, these representations were found to be veridical to their physical counterparts for both learning tasks. For extrafoveal view, they were severely distorted for category learning but not for discrimination learning. A variance reduction of the pattern classes by a factor of 100 reduced the dissociation between extrafoveal categorization and discrimination but did not remove it. These observations suggest a scale-invariant superiority of foveal vision for learning object categories. This implies a high degree of space variance of visual cognition which is vastly underestimated by classical measures of visual performance, e.g. acuity, visual field and contrast sensitivity.  相似文献   
96.
聂磊  罗国安  曹进  王义明 《药学学报》2004,39(2):136-139
目的用二维信息数据表征中药指纹图谱样本,并对其进行模式识别。方法对一维信息数据和二维信息数据表征的中药指纹图谱进行聚类分析,并对分析结果进行比较。结果与一维信息数据相比,采用二维信息数据表征指纹图谱,各种聚类方法所得总体类别差异小,样本归属比较稳定。对未知样本的类别判定聚类分析和神经网络预测结果一致。结论二维信息数据较一维信息数据更能全面、特异地表征中药指纹图谱。  相似文献   
97.
The purpose of this study was to determine changes in nasal respiratory pattern with growth and development, particularly to determine the age where upper airway growth ceases. The results on 361 healthy subjects, aged 7 to 24 years, based on aerodynamic measurements during rest breathing, showed clear differences between inspiratory and expiratory phases. Nasal airflow rate and cross-sectional area increased and oral-nasal pressure and nasal resistance decreased with age up to the age of 16, levelling by the age of 20 years. The body size and gender had effect only on nasal airflow rate. This study suggests that the measurements of the nasal respiratory pattern, determining impaired nasal airway, should be done during inspiration and using age-related assesment from a healthy population until the age of 16 years. From then on, guidelines for adults are applicable.  相似文献   
98.
AIMS—To identify the patent ductus arteriosus (PDA) shunt flow pattern using Doppler echocardiography; and to assess whether it could be used to predict the development of clinically significant PDA.
METHODS—Premature infants weighing under 1500 g, who required mechanical ventilation, and in whom daily echocardiography could be performed from day 1 until the ductus closed, and on day 7 to confirm closure, were studied. The PDA shunt flow was identified from four Doppler patterns, and the closed pattern of a closed duct was also presented. Clinically significant PDA was diagnosed when there was colour Doppler echocardiographic evidence of left to right ductal shunt associated with at least two of the following clinical signs: heart murmur (systolic or continuous); persistent tachycardia (heart rate>160/min); hyperactive precordial pulsation; bounding pulses; and radiographic evidence of cardiomegaly or pulmonary congestion.
RESULTS—Of 68 infants enrolled into this study, clincally significant PDA developed in 31. The most recordable sequence of transition change of shunt flow pattern for clinically significant PDA was: pulmonary hypertension pattern, to growing pattern, to pulsatile pattern, to closing pattern, to closed pattern. And that for non-clinically significant PDA was: pulmonary hypertension pattern, to closing pattern, to closed pattern. The growing and the pulsatile patterns were mostly documented in infants with clinically significant PDA. The first documented growing pattern to predict clinically significant PDA gave a sensitivity of 64.5% and a specificity of 81.1%; the first documented pulsatile pattern gave a sensitivity of 93.5% and a specificity of 100%.
CONCLUSION—Doppler echocardiographic assessment of PDA shunt flow pattern during the first 4 days of life is useful for predicting the development of clinically significant PDA in premature infants. At that stage, the closing or closed Doppler pattern indicates that infants are not at risk of developing clinically significant PDA; the growing or pulsatile Doppler pattern indicates a continuing risk of developing clinically significant PDA.

  相似文献   
99.
人体寄生虫虫卵图像的自动识别   总被引:7,自引:0,他引:7  
本文对显微医学图像的自动识别进行了初步研究,在微型计算机上实现了血吸虫等十余种人体寄生虫虫卵显微图像的预处理、分割、特征提取及识别与分类。通过对一批检验样本的识别分类,取得了正确率为92%的较好结果。  相似文献   
100.
We calculated the standardized mortality ratios (SMRs) of biliary tract cancer (BTC) in Japan from 1981 to 1990 and statistically analyzed the results according to 333 Secondary Areas of Medical Care, as well as sex and subsite [gallbladder cancer (GBC) and extrahepatic bile duct cancer (BDC)], in order to examine geographic clustering patterns of BTC. In GBC in both sexes, the Secondary Areas of Medical Care with high SMRs were clustered in the eastern part of Japan. In BDC in both sexes, the Areas with high SMRs were clustered between the northern and eastern parts of Japan. In comparison with GBC, this clustering favored the northern part of Japan. In males, the clustering pattern in mortality from BTC was mainly due to the occurrence of BDC. In females, the clustering pattern in mortality from BTC reflected that of GBC. The clustering of BTC, especially GBC, seems to be related to the distribution of plains, basins, and rivers.  相似文献   
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