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21.
22.
本文用OMEGA 500型Υ相机和MCS 560计算系统,即SPECT,R波门控采集心血池图象,在此基础上进行曲线分析,编制BASIC程序计算11项心功能指标。临床应用结果表明:PFR、LVFF、FFR是舒张期功能的优选指标,其它指标对心功能评价也都有显著意义。 相似文献
23.
童家明 《中国医学物理学杂志》2006,23(3):233-235
根据七年制医学生培养要求,在“生物物理技术”教学中,除介绍有关物理方法与技术的原理及在生物医学中的应用外,还尝试了小论文写作和渗透科研思路、方法培养的探索。 相似文献
24.
W. Hening M. Favilla C. Ghez 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1988,71(1):116-128
Summary This study was undertaken in order to determine the time course of the process by which information derived from a visual target is used to accurately set the amplitude of a simple motor response. We refer to this process as response specification. Separate auditory and visual cues were given to the subjects in order to independently control the moment of response initiation and the time available for processing amplitude information from the target. Six subjects initiated impulses of isometric force in synchrony with the last of predictable series of regular tones. Response amplitudes were to match one of three visual target steps occurring at random times between 0 and 400 ms before the response-synchronizing tone. Using these separate auditory and visual cues, we were able to systematically vary the time interval between target presentation and response onset, termed here Stimulus-Response or S-R interval. Target steps were presented in blocks of either predictable (simple condition) or unpredictable (choice condition) amplitudes. The peak forces and the peaks of their time derivatives were analyzed to determine how subjects achieved accuracy under the different conditions and at different S-R intervals. The trajectories of responses produced in the simple condition were independent of the S-R interval. In contrast, when targets were presented in unpredictable order, the distribution of the peak forces of the subjects' responses depended on the S-R interval. At short S-R intervals (<125 ms), subjects made responses whose peak forces were distributed around the center of the range of target steps. These responses formed a unimodal, but broad distribution which was independent of actual target amplitude. With increasing S-R interval (>125 ms), the distributions of peak forces gradually shifted toward the correct target amplitudes, with the means reaching the appropriate amplitudes at S-R intervals of 250–400 ms. At S-R intervals comparable to a reaction time, the range of peak forces was constricted to a similar extent as previously observed in a reaction time task (Hening et al. 1988). We found that the gradual improvement of accuracy was not achieved through changes in trajectory control: at all S-R intervals, subjects utilized a pulse-height control policy (Gordon and Ghez 1987a). Different peak forces were achieved by varying the rate of rise of force, while force rise time was held relatively invariant. We did find, however, that within the constraints imposed by rise time regulation, compensatory adjustments to the force trajectories (Gordon and Ghez 1987b) were greatest during the period of specification. We conclude that (1) subjects can initiate their responses independent of the degree of specification achieved and that the normal process of specification of amplitude begins earlier and continues longer than the latency of responses in a reaction time task; (2) before target presentation, subjects prepare a default response whose amplitude is biased by prior experience with the targets presented in the task. We hypothesize that the central mechanisms that specify response amplitude do so by a progressive adjustment of the default parameters. 相似文献
25.
Y. Nose M. Nakamura T. Inoue O. Nakagaki Y. Watanabe M. Yokota T. Tajimi A. Kuroiwa J. Hattori M. Miura 《Medical & biological engineering & computing》1980,18(6):727-730
The reliability of the Japanese public telephone facilities to transmit electrocardiograms (e.c.g.) for computer interpretation
was assessed. The International Business Machine's (IBM) e.c.g. computer program by Bonner was used. No appreciable distortion
of e.c.g. was observed following repeated transmission from hospitals separated by 1000 km. Thirty-four normal and 66 abnormal
e.c.g.s. were transmitted twice. Identical results were observed in 97% of normals and 92% of abnormals.
Following these fundamental experiments, 1236 patients' e.c.g.s. were transmitted for computer intepretation. The study showed
that 98·6% (1219 cases) were technically satisfactory and 1·4% (17 cases) were not. The 17 unsatisfactory cases were classified
into ten unreceivable data formats, six inconsistent measurements and one unacceptable noise level.
The authors concluded that the Japanese public telephone facilities were acceptable for the transmission of e.c.g.s. for computer
interpretation. 相似文献
26.
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
27.
教育心理学和教学效益相关性的研究 总被引:1,自引:0,他引:1
陈峰 《中国健康心理学杂志》2005,13(1):1-3
本研究在罗马尼亚Oradea大学医药学院进行,始于1998年,结束于2003年。研究的出发点为该学院的学生们提出不少的教师,包括一些国内外知名的学者和医生,因缺乏教育心理学知识,不能很好地理解学生,组织教学和传授知识。因此,本研究设置了问卷调查,学院向教员开设了教育心理学课程(1998年10月~1999年7月),与学生和教师座谈,统计并比较学生的考试成绩,特别地跟踪研究全国年度(1999年~2003年)医学证书汇考结果。研究结果客观地证实了教育心理学能够提高学习(工作)效益和成果,因为教育心理学知识使得教师(和医师)更好地与学生(或病人)沟通、理解和组织、合作。 相似文献
28.
Nienke Van Der Stoep Wouter Korver Ton Logtenberg 《European journal of immunology》1994,24(6):1307-1311
Molecular analysis of circular excision products and composite genomic switch regions has demonstrated that in mice, immunoglobulin (Ig) isotype switching from IgM to IgE often proceeds sequentially via IgG1. Based on analysis of Ig production in cell cultures, it has been suggested that human B cells may switch to IgE via IgG4, whereas limited molecular data from in vitro switched B cells suggest a direct IgM to IgE switch program. To obtain a quantitative assessment of direct versus sequential IgE switching in humans, we have analyzed the nucleotide sequences of 29 composite Sμ/S? switch regions from freshly isolated human B lymphocytes from patients with atopic dermatitis and from B lymphocytes induced to switch to IgE synthesis in vitro. The data show that in these B cells IgE isotype switching progressed directly from IgM to IgE. We conclude that, in contrast to the murine IgM/IgE switch program, the IgM to IgE switch in B lymphocytes from patients with atopic dermatitis as well as in vitro stimulated B cells from healthy donors preferentially proceeds via direct Sμ to S? switch recombination. 相似文献
29.
M. Neri G. B. Migliori A. Spanevello D. Berra E. Nicolin C. V. Landoni L. Ballardini M. Sommaruga P. Zanon 《Allergy》1996,51(5):313-319
The aims of the present study were as follows:
- 1). to evaluate the medical outcomes of two treatment and educational asthma programs
- 2). to determine by cost-analysis both cost and economic outcome of the programs
- 3). to perform a cost-benefit analysis (determining the net cost-benefit) and a cost-effectiveness analysis (determining the cost per unit of effect and the incremental cost-effectiveness ratio) from the perspective of health program policy makers (HPP; indirect costs, i.e., loss of productivity, excluded) and of society as a whole (Saw; all costs included).
30.
William R. Gillespie Peter Veng-Pedersen 《Journal of pharmacokinetics and pharmacodynamics》1985,13(3):289-307
A new deconvolution algorithm (DCON) suitable for pharmacokinetic applications is presented. It requires that both the impulse and input responses, typically systemic drug levels, be well described by polyexponential equations. DCON has a wider range of applications than an earlier method (DECONV) from which it is derived. A FORTRAN program is provided, making implementation of the technique a simple matter. DCON is demonstrated to evaluate the GI bioavailability, defined as the rate and the extent of gastrointestinal drug release, of various ibuprofen dosage forms. The GI drug release kinetics exemplifies a pharmacokinetic system which cannot be evaluated using the previous deconvolution algorithm (DECONV) because of an initial zero drug level response. This limitation is not found in DCON. It is also demonstrated how the mean in vivo dissolution time MDT can be evaluated by deconvolution. 相似文献