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Using an information-theoretic approach, causality between the systolic amplitude in blood pressure and the frequency of the heart beat was analyzed. Blood pressure and ECG were noninvasively recorded in young, healthy subjects. Three successive measurements were performed: during spontaneous breathing and during paced respiration—at frequencies both higher and lower than that of spontaneous respiration. We demonstrate that the amplitude and frequency of the cardiac rhythm are synchronized for most of the time. The synchronization is stronger during paced respiration at a frequency lower than that of spontaneous breathing. Episodes where the cardiac frequency was driven by the systolic pressure were also detected during slow, paced respiration. 相似文献
24.
现代中医药发展战略思考 总被引:1,自引:0,他引:1
建国几十年来,由于党和政府的大力提倡和扶持,中医药得到了很大发展,但相对于西医的发展势头仍显不足。尤其是近10多年来,由于现代科技及现代管理学的有力推动,西医获得了突飞猛进的发展,然而,中医却由于种种原因发展相对缓慢。在这各行各业竞相发展的现代社会,中医要生存,就蓝须发展,中医要发展,就妊须总揽全局,从战略高度克服中医药发展的各种不利因素,充分发挥各方面的有利条件。 相似文献
25.
Decisions about which health-care interventions represent adequate value to collectively funded health-care systems are as widespread as they are unavoidable. In the case of new pharmaceuticals, many countries now require formal cost-effectiveness analysis to inform this decision-making process. This requires evidence on parameters associated with health-related utilities, treatment effects, resource use, and costs, for which data from available regulatory trials are invariably absent or highly uncertain. This uncertainty results from a number of factors including the predominance of intermediate end points in the clinical evidence-base and the limited period of follow-up of patients in clinical studies. Despite these imperfections in the evidence base, decisions about whether new pharmaceuticals are sufficiently cost-effective for reimbursement cannot be side-stepped. Data limitations do, however, require the use of rigorous analytical methods to support decision making. Probabilistic decision models and value of information analysis offer a means of structuring decision problems, synthesizing all available data, characterizing the uncertainty in the decision, quantifying the cost of uncertainty, and establishing the expected value of perfect information. This analytical framework is important because it addresses two fundamental questions about new pharmaceuticals. First, is the product expected to be cost-effective on the basis of existing evidence? Second, is additional research concerning the product itself cost-effective? In addressing these questions, the analytical framework can establish when sufficient evidence exists to sustain a claim for a new pharmaceutical to be cost-effective. 相似文献
26.
N. M. van Schoor D. L. Knol C. A. W. Glas R. W. J. G. Ostelo A. Leplège C. Cooper O. Johnell P. Lips 《Osteoporosis international》2006,17(4):543-551
Introduction Vertebral deformities are a common consequence of osteoporosis and are known to decrease quality of life. The Qualeffo–41
is a quality-of-life questionnaire especially developed for measuring quality of life in patients with vertebral deformities.
It consists of 41 questions arranged in five domains: pain, physical function, social function, general health perception,
and mental function. The objectives of this study were: (1) to develop a shorter version of the Qualeffo–41 by removing redundant
questions; and (2) to investigate the scale characteristics, reliability, and validity of this shorter version.
Methods The study was performed using data from the Qualeffo validation study and the Multiple Outcomes of Raloxifene Evaluation (MORE)
study. The analyses were performed in patients with vertebral deformities (n=579). Factor analysis on polychoric correlations and an item response theory (IRT) model, i.e., the generalized partial credit
model (GPCM), were used to create a shorter version of Qualeffo–41. Using GPCM, scoring weights were computed for all items.
Results Three items were removed from the data set because of too many missing values. Factor analysis identified three instead of
five domains: (1) pain, (2) physical function, and (3) mental function. Five items had factor loadings <0.4 and were not included
in the GPCM. After excluding several items, the domains pain (four items), physical function (18 items), and mental function
(nine items) showed a good, reasonable, and excellent fit, respectively. This indicates that the mental function domain and
the pain domain are more unidimensional than the physical function domain. All three domains showed a very high correlation
(r ≥0.95) with the corresponding domains of the Qualeffo–41.
Conclusions Qualeffo–31 was developed, consisting of three domains with a reasonable to excellent fit to the GPCM. Although the fit to
the GPCM supports the construct validity of the Qualeffo–31, validation in a new study should be performed before using it
in practice. 相似文献
27.
夏桂成 《南京中医药大学学报》2003,19(4):204-206
阐述了时相与阴阳的关系,阴阳昼夜的盛衰转换与经脉循行、气血流注密切相关;对传统流注说和任督为主的阴阳循环说进行了分析,认为子午流注阴阳盛衰转换在妇科学中有重要意义,子午流注所指出的4个较重要的时期与月经周期中的4期(行经期、经后期、经间排卵期、经前期)相关。重视研究日相阴阳太极钟的变化,将能更加深入地认识月经周期中阴阳消长转化的规律变化,从而推动中医妇科学向前发展。 相似文献
28.
数字化校园构建之理论基础探讨 总被引:3,自引:3,他引:0
从总结数字化建设的实际出发,从建构主义教学理论、教育传播理论和管理科学理论三个方面,较为全面地论述了构建数字化校园的理论基础,并探讨了在数字化校园建设中如何应用理论来指导实际工作. 相似文献
29.
论中医病因、致病因素、邪气、邪之关系 总被引:2,自引:0,他引:2
张光霁 《浙江中医药大学学报》2007,31(6):676-677
邪是一切不正常、不正当的因素,邪气是邪的一部分,主要指六气异常以及疫疠之气等外感因素。两者可以独立于人体而存在,也可以进入人体,成为可能导致疾病的因素,即致病因素,邪(邪气)进入人体是致病因素,未进入人体不是致病因素。未导致疾痛的致病因素不是病因,已经引起疾病的致病因素是病因。 相似文献
30.
Michael S. Runyon MD Peter B. Richman MD Jeffrey A. Kline MD 《Academic emergency medicine》2007,14(1):53-57
Background Several clinical decision rules (CDRs) have been validated for pretest probability assessment of pulmonary embolism (PE), but the authors are unaware of any data quantifying and characterizing their use in emergency departments. Objectives To characterize clinicians' knowledge of and attitudes toward two commonly used CDRs for PE. Methods By using a modified Delphi approach, the authors developed a two‐page paper survey including 15 multiple‐choice questions. The questions were designed to determine the respondents' familiarity, frequency of use, and comprehension of the Canadian and Charlotte rules. The survey also queried the frequency of use of unstructured (gestalt) pretest probability assessment and reasons why physicians choose not to use decision rules. The surveys were sent to physicians, physician assistants, and medical students at 32 academic and community hospitals in the United States and the United Kingdom. Results Respondents included 555 clinicians; 443 (80%) work in academic practice, and 112 (20%) are community based. Significantly more academic practitioners (73%) than community practitioners (49%) indicated familiarity with at least one of the two decision rules. Among all respondents familiar with a rule, 50% reported using it in more than half of applicable cases. A significant number of these respondents could not correctly identify a key component of the rule (23% for the Charlotte rule and 43% for the Canadian rule). Fifty‐seven percent of all respondents indicated use of gestalt rather than a decision rule in more than half of cases. Conclusions Academic clinicians were more likely to report familiarity with either of these two specific decision rules. Only one half of all clinicians reporting familiarity with the rules use them in more than 50% of applicable cases. Spontaneous recall of the specific elements of the rules was low to moderate. Future work should consider clinical gestalt in the evaluation of patients with possible PE. 相似文献