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51.
A program called “An Epidemiological Approach to Computerized Medical Diagnosis” (AEDMI) is presented. Using an interactive questionnaire, physician-patient interviews are conducted and a summary of the relevant clinical data is provided. Standard items, obained on a multi-centre basis, form a large-scale data base. Simultaneously, the reasoning of clinical experts in each real case is analyzed to obtain a knowledge-rules data base. The methodology of the program combines Bayesian systems, expert systems, and other new lines of researcg such as neural networks or case-based reasoning. The general concepts of clinical decision making aid systems are reviewed. This publication is aimed at obtaining international cooperation.  相似文献   
52.
为了研究不同心电序列转换方式及不同谱估计方法对心率变异性(HRV)信号谱分析结果的影响,本文对积分脉冲频率调制(IPFM)模型及修正积分脉冲频率调制(MIPFM)模型在输入不同振幅与频率的正弦信号时所产生的随机点过程,用两种心电序列转换方法进行转换得到仿真HRV信导;然后,采用周期图与自回归(AR)谱估计方法计算这种厉真HRV信号的功率谱。研究结果表明:①对于MIPFM模型产生的随机点过程,同一心电序列转换方法所得出的仿真HRV信号的AR谱与周期图的谱峰功率估计基本一致;而对IPFM模型则不完全一致。②MIPFM模型仿真实验表明,对实际HRV信号谱分析,使用低,高频谱峰功率比(RF)作为反映心脏自主神经张力平衡的指标时,除心电序列传换及谱估计方法可能造成的误差外,当低频谱峰靠近极低频谱峰时,根据RF值解释生理实验结果会有校大误差。③座分析实际HRV信号的工作中,不同心电序列转换方式产生的伪谐波对HRV谱分析结果的影响不大。  相似文献   
53.
本文用计算机图象处理技术对细胞显微图象进行处理和定量分析,求出了细胞面积在低温保存中极其重要的参数。实验证明,计算机测量比人工精度高,误差小,同时新颖的标号去噪方法也非常有效。  相似文献   
54.
外科手术计算机辅助导航技术   总被引:10,自引:0,他引:10  
外科手术计算机辅助导航即利用计算机图形图像技术对放射影像学资料进行处理 ,重建二维或三维的医学图像模型 ,同时结合各种空间定位技术 ,在医师的双眼、手术工具及患者的头部之间建立一个实时的环路 ,实现手术过程中器械位置的实时或准实时显示。我们综述了外科手术计算机辅助导航系统的发展历史和研究现状 (重点阐述了其系统结构和关键技术 ,包括空间定位技术、图像处理与显示技术、系统配准技术、头部定位技术等 (最后给出了手术导航系统的发展趋势  相似文献   
55.
Fluctuating asymmetries are small random deviations from perfect symmetry in bilateral traits caused by the inability of individuals to cope with stress during development. The degree of asymmetry of secondary sexual characters is supposed to convey information about a male's phenotypic and/or genetic quality, and females are thus expected to use bilateral symmetry as a cue in mate choice. We offered female three-spined sticklebacks (Gasterosteus aculeatus L.) that had been inbred for one generation and outbred control females the choice between computer-animated male models differing exclusively in the symmetry of their pelvic spines. Inbred females exhibited a significantly stronger preference for the symmetric model than outbred females, suggesting that females of relatively poor quality are more prepared to pay the costs of choosiness and obtain higher marginal benefits from their discrimination than females of better quality.  相似文献   
56.
The core curriculum in the education of medical informaticians remains a topic of concern and discussion. This paper reports on a survey of medical informaticians with Master's level credentials that asked about computer science (CS) topics or skills that they need in their employment. All subjects were graduates or "near-graduates" of a single medical informatics Master's program that they entered with widely varying educational backgrounds. The survey instrument was validated for face and content validity prior to use. All survey items were rated as having some degree of importance in the work of these professionals, with retrieval and analysis of data from databases, database design and web technologies deemed most important. Least important were networking skills and object-oriented design and concepts. These results are consistent with other work done in the field and suggest that strong emphasis on technical skills, particularly databases, data analysis, web technologies, computer programming and general computer science are part of the core curriculum for medical informatics.  相似文献   
57.
National Taiwan University College of Medicine (NTUCM) introduced small groups of teaching and basic-clinical integrated courses for medical students in 1992. By using computer network and multimedia techniques, this study tried to overcome barriers to learning in small group teaching. The Department of Medical Informatics of NTUCM established campus networking and computer classrooms and provided Internet and intranet network services including mail, netnews, bulletin board systems (BBS), world wide web (WWW), gopher, ftp and local file servers. To implement an interactive learning environment, the authors first tried mail lists, newsgroups and BBS. Next an integrated learning system prototype on the WWW was developed to provide functions including online syllabus, discussion boards simulated to BBS, online talk, interactive case studies, virtual classroom with video on demand (VOD) and Internet medical resources. The results showed that after the medical students completed the required course of medical informatics and had good network access using a network to communicate with each other became a daily practice. In the future, the system will extend to the tutoring of clinical practice and continuing medical education. The authors expect a national medical education network and more international cooperation and exchange.  相似文献   
58.
An experimental animal hypoxia model has been developed. It consists of two sensors (an in vitro and in vivo model), an experimental device and a computer signal processing system. This method can easily be applied to determine and analyse blood oxygen saturation at various hypoxia levels. It can also be used to evaluate the accuracy of pulse oximetry over a wide range of oxyhemoglobin desaturation levels. The DC and AC components of recorded red and infra-red signals, the dual-wavelength ratio R12 and the reading of a pulse oximeter (SpO2) can be automatically calculated and displayed on a computer screen. Preliminary results of the animal hypoxia test indicate that the measurements made by the instrument correlate well with the oxygen saturation readings of the automatic blood gas analyser AVL945. The computer analysis system is suitable for repeated estimations in the animal model.  相似文献   
59.
A PC-AT based program for conversion of magnetic resonance imaging (MRI) scans into coordinate input for finite element mesh generation is presented. The program is written in Borland C + +3.1 and is compatible with every general-use personal computer, permitting the use of MS-DOS 3.0 or higher with a Microsoft mouse. The program is menu driven and does not demand specialised knowledge from the user. The system and memory requirements are minimal -- 640 kB RAM -- and it runs as a stand-alone program. A second program allows the construction of a three-dimensional representation of the limb sub-structure and generation of the FE mesh from the converted cross-sectional scans. The capabilities of the program are demonstrated using cross-sectional scans of the upper arm; the fat, muscle and bone contours were obtained to a very high level of precision (0.4 mm).  相似文献   
60.
髋臼CT图像轮廓跟踪方法   总被引:2,自引:2,他引:2  
目的为重建和测量髋臼的解剖结构,需要大量地读取CT图像的信息,以获得髋臼轮廓的坐标值。方法本研究采用直方图阈值图像分割、kirsh边缘提取法获得髋臼的二值化轮廓图像。轮廓坐标的提取应用了“迷宫”边缘跟踪算法。结果本方法可大量、快捷、正确的提取图像轮廓信息。  相似文献   
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