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11.
中药药性量化方法对补虚药功效归类预测的研究 总被引:6,自引:0,他引:6
目的对中药药性依其重要性进行更深层次的多值量化分析,将比定性的文字表述和简单的二值量化表示更有意义.方法以补虚药为研究对象,药性为基本特征,在对其进行二值量化和多值量化的基础上,采用应用人工神经网络和决策树等数据库知识发现技术,进行对补虚药功效归类判别结果的影响研究.结论结果表明药性的不同量化方法对补虚药的功效归类预测有一定影响,多值量化比二值量化具有更为理想的判别结果. 相似文献
12.
The use of biochemical markers of bone turnover has been advocated to improve follow-up of women receiving antiresorptive
therapies for osteoporosis, but this strategy is not yet supported by trials showing it improves effectiveness of treatments.
To explore the potential value of markers of bone turnover to monitor antiresorptive treatments of osteoporosis, we conducted
a decision analysis using a decision tree and Markov modeling. We have compared two strategies: treatment of a woman without
specific monitoring; and treatment of this woman with measurement of a serum marker of bone resorption after 3 months of treatment,
with change of treatment if response to treatment assessed by this marker was not satisfactory. The base case is the treatment
of a 60-year-old osteoporotic woman with a total hip T-score of −3, using a second generation bisphosphonate during 5 years. We found that follow-up produced slightly greater quality
adjusted life years (QALYs) than no follow-up (8.1560 vs 8.1532, i.e. a one day difference). In a two-way sensitivity analysis,
the follow-up option produced higher QALYs so long as adherence rate with follow-up was equal or superior to the proportion
of women who adhered without follow-up. For example, if the proportion of women adherent to treatment was increased from 50%
to 60% by follow-up, then the expected value of the follow-up branch was increased from 8.1560 QALYs to 8.1800 QALYs (i.e.
a difference of 9 days). In addition, the higher the non-response rate, the greater the benefit from monitoring with a biochemical
marker. In conclusion, our decision analysis model suggests that follow-up of osteoporotic women treated with a second generation
bisphosphonate during a 5-year period using an early measurement of a serum marker of bone resorption may increase effectiveness
of the treatment on quality of life, but the effect is very small. So, the use of follow-up measures of bone turnover may
be based on patient and physician preferences.
Received: 6 July 2001 / Accepted: 1 April 2002 相似文献
13.
Objective
This study investigated how health care provider communication of risk information, and women’s role in decision-making, influenced women’s preferences for mode of birth after a previous caesarean birth.Methods
Women (N?=?669) were randomised to one of eight conditions in a 2 (selectivity of risk information) × 2 (format of risk information) × 2 (role in decision making) experimental design. After exposure to a hypothetical decision scenario that varied information communicated by an obstetrician to a pregnant woman with a previous caesarean birth across the three factors, women were asked to decide their preferred hypothetical childbirth preference.Results
Women provided with selective information (incomplete/biased toward repeat caesarean) and relative risk formats (ratio of incidence being compared e.g. 2.5 times higher), perceived lower risk for caesarean and were significantly more likely to prefer repeat caesarean birth than those provided with non-selective information (complete/unbiased) and absolute risk formats (incidence rate e.g. 0.01 per 100). Role in decision-making did not significantly influence childbirth preferencesConclusions
Modifiable aspects of healthcare provider communication may influence women’s decision-making about childbirth preferencesPractice implications
Optimised communication about risks of all options may have an impact on over-use of repeat CS. 相似文献14.
Second Thoughts: Multiple P300s Elicited by a Single Stimulus 总被引:3,自引:0,他引:3
In a previous report (Johnson & Donchin, 1978), we manipulated the discriminability of tone pairs that delivered feedback information in a time-estimation paradigm. As in other experiments using feedback stimuli, the event-related potentials elicited by these stimuli did not return to baseline in the 800-ms poststimulus interval. Since we were interested in this “Slow Wave'’activity, the poststimulus interval was lengthened to 1500 ms. Averages revealed that a second positive peak was present for some of the individual subjects. To investigate this activity further, the filtered singletrial waveforms were inspected visually. These data were characterized by the presence of one, and occasionally two, positive peaks, with highly variable latencies, following the P300. These peaks were indistinguishable in frequency and general appearance from the P300s elicited by the feedback stimuli. After latency adjusting the waveforms on the peak of the second positive wave, amplitude and latency were quantified. Whereas P300 amplitude was directly related to stimulus discriminability and positive feedback elicited larger P300s than negative feedback, the amplitude of the second positive wave was constant across levels of discriminability and the same for both types of feedback. In contrast, the latencies of both waves were inversely related to stimulus discriminability and shorter following positive feedback than negative feedback. Evidence is presented to support our contention that these additional positive peaks represent P300 activity. The data are discussed in terms of what these multiple P300s reveal about human information processing. 相似文献
15.
A computerized decision support system is presented. The system is used to aid in the situation of patient selection for the purpose of dental education and utilizes the PERT/CPM methodology and decision tables. It runs on a microcomputer and written in Basic. The input is a list of patient's needs, and the output is a tentative treatment plan, the chair time needed to complete the treatment, its cost, and the probability that the student will finish it on time. 相似文献
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This paper constructs a unified framework to survey most of the work done to date on decision 1 decision horizon replaces the term planning horizon used in the literature in the context of this paper. This is done because of an alternate and more popular use of the term planning horizon as simply the given length of the horizon in a finite horizon problem. and forecast horizons in a stochastic environment. The paper is divided into sections by type of model. For each model type, the issues of existence of these horizons and of derivation of sufficient conditions for their determination are studied. Appropriate examples are presented. 相似文献
18.
目的基于主成分分析(PCA)-决策树模型分析脑卒中肺部感染的危险因素及血清免疫炎性因子的预测价值。方法回顾性分析2014年12月-2019年12月江西省上饶市人民医院确诊的176例脑卒中患者,根据是否发生肺部感染,分为感染组40例和未感染组136例。记录患者临床特征,检测血白细胞(WBC)计数、血清C-反应蛋白(CRP)、降钙素原(PCT)和可溶性白细胞介素-2受体(SIL-2R)水平。采用Logistic回归和卡方自动交叉检验(CHAID)模型分析影响脑卒中后肺部感染的危险因素;受试者工作特征曲线(ROC)分析血WBC、CRP、PCT、SIL-2R预测肺部感染的价值。结果脑卒中肺部感染与患者年龄、卒中类型、是否合并糖尿病、吸烟史、吞咽困难、意识障碍、侵入性操作有关(P<0.05);感染组患者血WBC、CRP、PCT和SIL-2R水平高于未感染组(P<0.05);糖尿病、侵入性操作、CRP和PCT均为影响脑卒中患者肺部感染的独立危险因素(P<0.05);PCA-ROC分析显示,血WBC、CRP、PCT、SIL-2R和联合预测主成分1(PC1)的曲线下面积(AUC)分别为0.670、0.816、0.854、0.686、0.918;PCA-卡方自动交互检测(CHAID)模型分析显示,WBC、CRP、PCT、SIL-2R和PC1预测肺部感染的准确率为77.33%、84.72%、86.90%、79.02%和89.24%。结论血清PCT水平可用于预测脑卒中患者肺部感染的发生,临床可重点关注合并糖尿病、意识障碍和侵入性操作的患者。 相似文献
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