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51.
52.
Abstract Daan's two process model is known to be one of the most powerful models, covering various situations from free-running to sleep deprivation. In this study, bifurcation properties of the model dynamics as function of a gap, D , between the threshold processes are clarified using a circle map. As a function of D , we will show that the model has the different types of the mutual entrainment regions that are intervened by the tangent bifurcation. The variable behavior of human circadian rhythm is suggested to be systematically understood based on the bifurcation properties of the two process model. 相似文献
53.
Objective: To explore patterns in the practice of nursing and patient outcomes.
Design: Qualitative field research.
Population, Sample, Setting: Populations were critical care nurses and critically ill adult patients in the 10-bed medical critical care unit of a 900-bed teaching hospital. A convenience-purposive sample of 27 nurses and 31 patients was studied in 1985.
Methods: Six months of participant observation, unstructured interviews, and the constant comparison method of grounded theory.
Findings: Markedly different patterns were found in expert and nonexpert practice. The substantive theory of conversion helped explain how the majority of nonexpert nurses advanced their practice. The metaphor of catalyzed conversion captures how a unit-based expert nurse serves as a catalyst to advance the practice of nonexperts. Presence, defined as the way of being within a given clinical context, differentiated nurses.
Conclusions: (a) Expert and nonexpert practices are substantively different, (b) Expert and nonexpert practice results in different patient outcomes, (c) Conversion helps explain changes in nonexpert practice.
Clinical Implications: A unit-based expert nurse can increase patient-focused care. 相似文献
Design: Qualitative field research.
Population, Sample, Setting: Populations were critical care nurses and critically ill adult patients in the 10-bed medical critical care unit of a 900-bed teaching hospital. A convenience-purposive sample of 27 nurses and 31 patients was studied in 1985.
Methods: Six months of participant observation, unstructured interviews, and the constant comparison method of grounded theory.
Findings: Markedly different patterns were found in expert and nonexpert practice. The substantive theory of conversion helped explain how the majority of nonexpert nurses advanced their practice. The metaphor of catalyzed conversion captures how a unit-based expert nurse serves as a catalyst to advance the practice of nonexperts. Presence, defined as the way of being within a given clinical context, differentiated nurses.
Conclusions: (a) Expert and nonexpert practices are substantively different, (b) Expert and nonexpert practice results in different patient outcomes, (c) Conversion helps explain changes in nonexpert practice.
Clinical Implications: A unit-based expert nurse can increase patient-focused care. 相似文献
54.
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
55.
目的 探索基于层次分析评价和模糊综合评价模型的临床医学课程思政实施效果评价体系构建和应用。方法 利用Yaahp软件构建基于层次分析评价和模糊综合评价模型的临床医学课程思政实施效果评价体系。在西安交通大学第一附属医院185名学生的内科学课程中实施德医并举的课程思政清单式教学,并在课程结束时应用此评价体系得到定量的综合评价结果。结果 基于层次分析评价和模糊综合评价模型构建了临床医学课程思政实施效果评价体系,以德医双馨的育人目标为目标层,师德师风、课程设计、学生体会、发展评估为准则层,分13项方案层。利用此评价体系评价2020至2021学年第一学期内科学课程思政实施效果,结果显示德医并举的课程思政清单教学具有良好的育人效果,定量综合评价得分4.080分(1~5分)。结论 临床医学课程思政实施效果的评价可基于层次分析评价和模糊综合评价模型构建,具有科学、定量、综合和可改进等特点。 相似文献
56.
枢椎齿突骨折的有限元分析 总被引:10,自引:3,他引:10
目的:建立枢椎的三维有限元(FE)模型,探讨在前、后方不同载荷下齿突的不同损伤机制和骨折类型。方法:对一例新鲜枢椎标本进行CT扫描,层厚1mm,扫描图像转换后输入微机,通过软件PRO/E重建枢椎的三维立体模型,再转入有限元软件MARK并赋予此模型物理材料属性,然后模拟齿突骨折的受力条件,在齿突中性矢状面对齿突施加不同角度的载荷,分析各种条件下枢椎模型的应力、应变分布,探讨相应条件下可能导致的枢椎齿突骨折类型。结果:(1)对于齿突前部斜向后下方载荷,应力集中区从齿突前上部斜贯穿至后下部;对于齿突前部斜向后上方载荷,应力集中区从齿突前下部斜贯穿至后上部;齿突腰部始终保持高应力;(2)在齿突后部载荷下,其应力集中情况与前部载荷相似,不过应力集中区位置有所偏下。结论:(1)在齿突中性矢状面,齿突前部载荷容易导致齿突腰部发生断裂,形成枢椎齿突Ⅱ型骨折,也可能导致基底部发生断裂,形成枢椎齿突Ⅲ型骨折;(2)齿突后部载荷更容易导致基底部发生断裂,形成枢椎齿突Ⅲ型骨折。 相似文献
57.
Potent inhibition of HIV-1 entry by (s4dU)35 总被引:2,自引:0,他引:2
Horváth A Tokés S Hartman T Watson K Turpin JA Buckheit RW Sebestyén Z Szöllosi J Benko I Bardos TJ Dunn JA Fésüs L Tóth FD Aradi J 《Virology》2005,334(2):214-223
58.
Koorengevel KM Beersma DG Den Boer JA Van Den Hoofdakker RH 《Journal of sleep research》2002,11(4):347-356
The majority of winter-type seasonal affective disorder (SAD) patients complain of hypersomnia and daytime drowsiness. As human sleep is regulated by the interaction of circadian, ultradian and homeostatic processes, sleep disturbances may be caused by either one of these factors. The present study focuses on homeostatic and ultradian aspects of sleep regulation in SAD. Sleep was recorded polysomnographically in seven SAD patients and matched controls subjected to a 120-h forced desynchrony protocol. In time isolation, subjects were exposed to six 20-h days, each comprising a 6.5-h period for sleep. Patients participated while being depressed, while remitted after light therapy and in summer. Controls were studied in winter and in summer. In each condition, the data of each subject were averaged across all recordings. Thus, the influence of the effects of the circadian pacemaker on sleep was excluded mathematically. The comparison of patients with controls and with themselves in the various conditions revealed no abnormalities in homeostatic parameters: sleep stage variables, relative power spectra and time courses of power in various frequency bands across the first three non-rapid eye movement-rapid eye movement (NREM-REM) cycles showed no differences. The data suggest that homeostatic processes are not involved in the disturbance of sleep in SAD. 相似文献
59.
介绍了一种新型生物组织微阵列芯片自动制备仪的研制。分析了组织微阵列制备过程中的操作任务和实现目标,进行了制备仪的结构设计和各功能模块研究开发。制备仪从结构上分为蜡块承载定位模块和三工位操作模块,控制系统的组成有操作空间精密定位子系统,组织蜡块图像识别子系统,蜡块打孔填埋作业子系统等。研制成功的制备仪样机具备了图像自动识别、精密定位、自动打孔填埋等功能,实现了生物组织微阵列芯片的自动化制备。 相似文献
60.
颈椎钩突邻近结构薄层断面与MRI对照研究 总被引:1,自引:1,他引:1
目的阐明颈椎钩突在薄层断面和MRI断面图像上与周围结构的毗邻关系,为颈椎退行性疾病提供影像学诊断依据。方法选取5例中国数字化可视人体(CVH)数据集中C3-C7椎体上缘清楚显示钩突的薄层断面图像,观察并测量钩突与邻近的椎动脉和颈神经的位置关系,选择对应平面的MRI断面图像对照分析。结果CVH数据集的薄层断面清晰显示颈椎钩突及其周围结构,在断面上测量并得出钩突与颈神经、钩突与椎动脉的距离的平均值,MRI清楚显示颈椎钩突及其邻近结构。结论将CVH数据集中的颈椎钩突平面的薄层断面与对应的MRI图像进行对照研究,可为颈椎病的影像学诊断和治疗提供形态学参考。 相似文献