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101.
神经网络分析方法用于心脏病诊断的研究 总被引:2,自引:1,他引:1
神经网络可以很好的拟合任意的非线性函数。我们从 QRS波群的高频三维频谱中提取出一些定量的特征参数 ,用神经网络的方法对这些参数进行有监督的学习训练 ,最终能在由这些特征参数张成的 m维空间中构建出一个 m维的曲面来区分病人和健康人的 QRS波群高频三维频谱 ,从而使得训练后的网络能基于 QRS波群的高频三维频谱自行诊断出病人和健康人 相似文献
102.
Recent changes in UK law have allowed UK-based optometrists to sell and supply fusidic acid viscous eyedrops, providing it is in the course of their professional activity and in an emergency. Alternatively, the optometrist may access fusidic acid viscous eyedrops, for a named patient, using a written order supplied to a pharmacy. This review provides details of the legal background to these changes, examines the common causes of a bacterial conjunctivitis, examines the mechanism of action of this narrow spectrum antibiotic as a bacteriostatic agent, reviews the susceptibility of common ocular isolates of bacteria to the drug and presents details of the expected pharmacokinetics of the viscous eyedrops. From this perspective, a systematic review is provided of the clinical studies which have investigated the use of fusidic acid viscous eyedrops and their outcome. The indicated use is generally for the treatment of bacterial conjunctivitis and/or blepharoconjunctivitis, especially that caused by Staphylococcus, but not Streptococcus or Haemophilus sp. (more likely associated with concurrent nasopharyngeal infections). The usual regimen for use is twice daily for 5-10 days, depending on severity, and can initially be used more intensively (four times per day). It may also be used for the management of corneal and conjunctival abrasions and foreign body injuries, or some cases of chronic blepharitis. 相似文献
103.
A. L. Rickards †‡ J. E. Walstab †‡ R. A. Wright-Rossi † J. Simpson† D. S. Reddihough†‡ 《Child: care, health and development》2009,35(5):593-602
Introduction There is debate about the type and intensity of early childhood intervention that is most helpful for children with developmental problems. The aim of the study was to determine whether a home‐based programme provided over 12 months resulted in sustained improvement in development and behaviour 12 months after the intervention ceased. The characteristics of the children and families who benefited most from the intervention were also studied. Method Randomized controlled trial. Participants A total of 59 children, aged 3–5 years, attending two early childhood intervention centres in Melbourne, Australia. Intervention Half of the subjects received an additional home‐based programme consisting of 40 weekly visits. Main outcome measures Bayley Scales of Infant Development and Wechsler Preschool and Primary Scale of Intelligence Revised, Preschool Behaviour Checklist, Bayley Behaviour Rating Scale and Behaviour Screening Questionnaire. All tests administered pre‐intervention, following the intervention and 12 months later. Secondary outcome measures Family stress, support and empowerment. Results Fifty‐four children completed the assessments 12 months after conclusion of the intervention. Compared with the control group, improvement in aspects of cognitive development in the children who received the extra intervention was sustained 1 year later (P= 0.007) while significant behavioural differences post intervention were not. Analyses of the data by the Reliable Change Index indicated improvement of clinical significance occurred in non‐verbal areas. In contrast to the control group who deteriorated, language skills in the intervention group remained stable. Improvements were significantly associated with higher stress in the families. Conclusion Improvements following the provision of a home‐based programme to preschool children with developmental disabilities were sustained 1 year later. Children from highly stressed families appeared to benefit most, reinforcing the importance of involving families in early childhood intervention programmes. 相似文献
104.
Nancy J Keuthen Nikos Makris John E Schlerf Brian Martis Cary R Savage Katherine McMullin Larry J Seidman Jeremy D Schmahmann David N Kennedy Steven M Hodge Scott L Rauch 《Neuropsychopharmacology》2007,61(3):374-381
BACKGROUND: Limited knowledge exists regarding the neurobiology of trichotillomania (TTM). Cerebellum (CBM) volumes were explored, given its role in complex, coordinated motor sequences. METHODS: Morphometric magnetic resonance imaging (MRI) scans were obtained for 14 female subjects with DSM-IV diagnoses of TTM and 12 age-, education-, and gender-matched normal control (NC) participants. Parcellation was performed utilizing a recently developed methodology to measure subterritory volumes of the CBM. Regions were defined based on knowledge of the structural and functional subunits of the CBM. RESULTS: As predicted, significant group differences were reported for CBM raw cortical volumes (p = .008) that survived correction for total brain volume (TBV; p = .037) and head circumference (HC; p = .011). A priori and post hoc group raw volume comparisons for CBM subterritories and functional clusters revealed many significant differences. However, most differences failed to withstand correction for total CBM volumes (TCV). Smaller volumes were consistently reported for the TTM versus NC cohorts. Total Massachusetts General Hospital Hair Pulling Scale (MGHHPS) scores were significantly inversely correlated with left primary sensorimotor cluster volumes (p = .008), with smaller volumes associated with more severe TTM symptoms. CONCLUSIONS: These findings implicate the CBM in the neurobiology of TTM, with reduced subterritory volumes reported for the TTM versus NC groups. 相似文献
105.
W. F. Harris 《Ophthalmic & physiological optics》2003,23(3):251-261
Traditional treatments of spectacle magnification for distant objects consider only stigmatic spectacle lenses and they compare the retinal image size in a refractively fully compensated eye with the image size in the uncompensated eye. Spectacle magnification is expressed as a product of two factors, the power and shape factors of the lens. The power factor depends on the position of the entrance pupil of the eye. For an eye with an astigmatic cornea, however, the position of the entrance pupil is not well defined. Thus, the traditional approach to spectacle magnification does not generalize properly to allow for astigmatism. Within the constraints of linear optics and subject to the restriction that the eye's iris remains the aperture stop, this paper provides a complete, unified and exact treatment for optical instruments in general. It compares retinal image size in a generalized sense (including image shape and orientation) for any instrument in front of an eye with that of the eye alone irrespective of whether the instrument compensates or not. The approach does not make use of the concept of the entrance pupil at all and it allows for astigmatism and for non-alignment of refracting elements in the instrument and in the eye. The concept of spectacle magnification generalizes to the concept of instrument size magnification. Instrument size magnification can be expressed as the product of two matrix factors one of which can be interpreted as a power factor (as back-vertex power) and the other factor for which the name dilation factor is more appropriate in general. The general treatment is then applied to a number of special cases including afocal instruments, spectacle lenses (including obliquely crossing thick bitoric lenses), contact lenses, stigmatic systems and stigmatic eyes. In the case of spectacle lenses, the dilation factor reduces to the usual shape factor. 相似文献
106.
W. F. Harris 《Ophthalmic & physiological optics》2003,23(6):561-565
A general expression is derived for the proximity factor in near image size magnification for an arbitrary instrument in front of an arbitrary eye. The proximity factor is a 2 x 2 matrix. The instrument and eye may be astigmatic and have decentred elements. The image on the retina may be blurred or not. The analysis is exact within the limitations of linear optics. The general results are specialized for the case of a stigmatic instrument and a stigmatic eye. The results are applied to the case of a thick, possibly bitoric, spectacle lens. The Appendix treats two numerical examples. 相似文献
107.
基于RFID的病人用药安全管理新技术探讨 总被引:1,自引:0,他引:1
目前,我国在病人用药安全方面存在的主要问题是:病人本人用药安全意识淡漠、政府和卫生机构管理乏力、医院内部管理不规范、缺乏合适且有效的高新技术的支持。针对这些问题,提出基于先进的RFID技术的病人用药安全管理的新技术和解决方案,从而提高病患在用药过程中的安全系数,辅助相关医疗管理人员对药物进行准确有效的使用,防止用药安全事故的发生。 相似文献
108.
Analysis of count data from clinical trials using mixed effect analysis has recently become widely used. However, algorithms
available for the parameter estimation, including LAPLACE and Gaussian quadrature (GQ), are associated with certain limitations,
including bias in parameter estimates and the long analysis runtime. The stochastic approximation expectation maximization
(SAEM) algorithm has proven to be a very efficient and powerful tool in the analysis of continuous data. The aim of this study
was to implement and investigate the performance of a new SAEM algorithm for application to count data. A new SAEM algorithm
was implemented in MATLAB for estimation of both, parameters and the Fisher information matrix. Stochastic Monte Carlo simulations
followed by re-estimation were performed according to scenarios used in previous studies (part I) to investigate properties
of alternative algorithms (Plan et al., 2008, Abstr 1372 []). A single scenario was used to explore six probability distribution models. For parameter estimation, the relative bias
was less than 0.92% and 4.13% for fixed and random effects, for all models studied including ones accounting for over- or
under-dispersion. Empirical and estimated relative standard errors were similar, with distance between them being <1.7% for
all explored scenarios. The longest CPU time was 95 s for parameter estimation and 56 s for SE estimation. The SAEM algorithm
was extended for analysis of count data. It provides accurate estimates of both, parameters and standard errors. The estimation
is significantly faster compared to LAPLACE and GQ. The algorithm is implemented in Monolix 3.1, (beta-version available in
July 2009). 相似文献
109.
Steven J. Davidson MD MBA Frank L. Zwemer Jr. MD MBA Larry A. Nathanson MD Kenneth N. Sable MD Abu N.G.A. Khan MD MS 《Academic emergency medicine》2004,11(11):1127-1134
Physician-generated emergency department clinical documentation (information obtained from clinician observations and summarized decision processes inclusive of all manner of electronic systems capturing, storing, and presenting clinical documentation) serves four purposes: recording of medical care and communication among providers; payment for hospital and physician; legal defense from medical negligence allegations; and symptom/disease surveillance, public health, and research functions. In the consensus development process described by Handler, these objectives were balanced with the consideration of efficiency, often evaluated as physician time and clinical documentation system costs, in recording the information necessary for their accomplishment. The consensus panel session participants and authors recommend that 1) clinical documentation be electronically retrievable; 2) selection and implementation be evidence-based and grounded on valid metrics (research is needed to identify these metrics); 3) the user interface be crafted to promote clinical excellence through high-quality information collection and efficient charting techniques; 4) the priorities for integration of clinical information be standardized and implemented within enterprises and across health and information systems; 5) systems use accepted standards for bidirectional, real-time clinical data exchange, without limiting the location or number of simultaneous users; 6) systems fully utilize existing electronic sources of specific patient information and general medical knowledge; 7) systems automatically and reliably capture appropriate data that support electronic billing for emergency department services; and 8) systems promote bedside documentation and mobile access. 相似文献
110.
Y. Ikemoto S. Demura S. Yamaji M. Minami M. Nakada M. Uchiyama 《Sport Sciences for Health》2007,2(2):64-70
Although explosive isometric contraction provides little work toward the outside, force-time parameters of the rising phase
of the force-time curve may be able to predict muscle power. The purpose of this study was to examine the relationship between
muscle power with work (power grip) and force-time parameters during the rising phase in explosive isometric grip. Fifteen
healthy young adult males participated in this study. Power grip was measured using loads of 20%–50% of maximal voluntary
contraction (MVC) (peak isometric force). Subjects pulled explosively on a grip bar held with the second digital joints without
the thumb. Peak power was calculated from peak velocity and load. Explosive isometric grip was measured using a hand dynamometer.
Time-series data of both tests were sampled by an analog-to-digital interface. Both tests were performed with the subjects
seated with a sagittal and horizontal position of the arm supported by an armrest. Peak power in the power grip test tended
to be larger with an increase of the load, but there was no significant difference between 40% and 50% MVC. Only the peak
power in 50% MVC significantly correlated with peak grip force (r=0.52, p<0.05). The force-time parameters related to the peak rate of the rising force phase in explosive isometric grip significantly
correlated with the peak powers (30%–50% MVC, r=|0.58−0.78|). Peak rate of the rising force phase in explosive isometric grip
may be useful for predicting muscle power with loads between 30%–50% MVC. 相似文献