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71.
Michael S. Sacks David B. Smith Erik D. Hiester 《Annals of biomedical engineering》1997,25(4):678-689
The planar fibrous connective tissues of the body are composed of a dense extracellular network of collagen and elastin fibers
embedded in a ground matrix, and thus can be thought of as biocomposites. Thus, the quantification of fiber architecture is
an important step in developing an understanding of the mechanics of planar tissues in health and disease. We have used small
angle light scattering (SALS) to map the gross fiber orientation of several soft membrane connective tissues. However, the
device and analysis methods used in these studies required extensive manual intervention and were unsuitable for largescale
fiber architectural mapping studies. We have developed an improved SALS device that allows for rapid data acquisition, automated
high spatial resolution specimen positioning, and new analysis methods suitable for large-scale mapping studies. Extensive
validation experiments revealed that the SALS device can accurately measure fiber orientation for up to a tissue thickness
of at least 500 μm to an angular resolution of∼1o and a spatial resolution of±254 μm. To demonstrate the new device’s capabilities, structural measurements from porcine aortic
valve leaflets are presented. Results indicate that the new SALS device provides an accurate method for rapid quantification
of the gross fiber structure of planar connective tissues. 相似文献
72.
Susan Kirk MSc BNurs RGN RM RHV DNCert Caroline Carlisle MSc BA RGN RM DNCert DipCouns RNT Karen A. Luker PhD BNurs RGN RHV DNCert 《Journal of advanced nursing》1997,26(5):1036-1044
A national study was conducted between 1991 and 1994 to explore and describe the changing role of the nurse teacher following the introduction of Project 2000 pre-registration nursing courses. Multiple methods were used to collect data from a wide variety of respondents (nurse teachers, midwife teachers, clinical nurses, health service managers and higher education lecturers). This paper presents the findings relating to the impact of Project 2000 and the move into higher education on the continuing educational needs of nurse teachers. Views on college strategies for staff development, the changing nature of teachers'academic and professional development needs and the problems of the conflicting demands experienced are reported. The research highlights the need for clinical credibility to be clearly defined in relation to nurse teachers and for educational institutions to place more emphasis on teachers'clinical development if the rhetoric of policy is to become a reality. 相似文献
73.
家兔右室乳头肌在含3mM EDTA、5mM Na_2ATP、10mM Tris、140 mM KCl的溶液中浸浴150min,其Ca~(2+)通透性显著增高。Ca~(2+)浓度为10~(-7)M时,便可产生张力,10~(-4.6)M时,张力达到最大。相对张力-pCa(Ca~(2+)浓度的负对数)关系近似一S形曲线,产生50%最大张力的Ca~(2+)(pCa_(50))约为10~(-6.6)M。同法制备的大鼠乳头肌Ca~(2+)通透性未见增高。 相似文献
74.
本文报道了肠系膜上静脉与下腔静脉侧侧分流术7例,并介绍了手术的体会,认为应解剖、暴露肠系膜上静脉“外科干”与相应平面的下腔静脉,清除两者间的增生组织,缩短两者的间距,才易取得手术成功。本术既可使门静脉压下降适中,又对门静脉向肝血流干扰较小,且对组织损伤较轻。 相似文献
75.
Alexander Poznyak Francisco Javier Bejarano Leonid Fridman 《Optimal control applications & methods.》2007,28(4):289-300
The minimax linear quadratic problem, where ‘max’ is taken over a finite set of indices (models) and ‘min’ is taken over the set of admissible controls, is considered. The solution is obtained by the robust optimal control application. The control turns out to be a linear combination of the controls optimal for each individual model. This paper develops a numerical method for the optimal weights adjustment. An example shows a quick convergence of the proposed procedure. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
76.
目的观察不同治疗方法在急诊剖宫产术中恶心呕吐的应用。方法选择ASAI~II级104例急诊剖宫产手术患者,随机分为五组:指揉组(n=21)、恩丹西酮组(n=21)、甲氧氯普胺组(n=21)、氟哌利多组(n=21)和生理盐水组(n=20)。采用腰-硬联合阻滞麻醉,术毕实施术后镇痛(patient controlled epidural analge-sia,PCEA)。结果指揉组、恩丹西酮组与甲氧氯普胺组与氟哌利多组VAS评分基本相当,与生理盐水组比较(P>0.01),各实验组之间比较(P>0.05),表明指揉组、恩丹西酮组、甲氧氯普胺组和氟哌利多组疗效相同。结论指揉法在防治急诊剖宫产恶心呕吐中,简便易行,效果确切,副作用少,适用于术中轻度恶心呕吐;而甲氧氯普胺和恩丹西酮更适于程度较重的恶心呕吐;氟哌利多抗恶心呕吐的作用时间相对较长。 相似文献
77.
Zhang Deli Chen Shulan 《宁夏医科大学学报》1987,(2)
Sinoatrial node electrogram (SNE) was recorded successfully in recent years, using transvenous electrode catheter. Via SNE and intratrialelectrogram (IEG), one could measure sinoatrial conduction time(SACT) directly, observe sinoatrial node (SN) potential changes in cadiac cycles, diagnose some sinus arrhythmias which couldn't be confirmed by surface ECG. All these could offer accurate evidence for differential diagnosis of sick sinus syndrome (SSS). The authors recommend a modified method for the location of the electrode catheter, by which one can increase success rate of obtaining stable SNE. Using this method, the authors recorded SNE in 10 cases with SSS successfully. 相似文献
78.
The aim of this study was to estimate the incidence of morbidity and mortality due to injuries in the population over the age of 14 years in Barcelona, Spain. Injury distribution according to sex, age, external cause, place of occurrence of the injury and severity was also obtained. A one-year survey was conducted in the emergency departments of the six main hospitals in Barcelona, based on a multistage sampling. Information was collected prospectively in emergency services by specially trained non-staff interviewers. Mortality data were drawn from death certificates. The incidence rate was 74.7 injury cases per 1,000 person-years over 14 years of age, higher in males than in females. Injury rates were highest in the youngest age-group and progressively lower until people over 75 years of age. Main external causes of injury were falls, being struck or caught by objects, and traffic-related injuries. The leading specific causes of injury mortality were traffic injuries, suicides and poisonings. While the overall admission incidence was 3.34 cases per 1,000 inhabitants, the proportion of hospitalized cases was 45.0 per 1,000 injury cases admitted to emergency rooms, higher for females, for traffic injuries and in the elderly population. Ninety-six percent of injury cases had an ISS value of 8 or less, mean ISS being highest for traffic injuries and falls. Injury morbidity and mortality amongst residents of Barcelona follow sex, age and cause of injury patterns which are, overall, comparable to those observed in other industrialized countries, suggesting that similar etiologic factors might be operating in those areas. The results should enable the orientation of injury prevention policies in the urban environment targeted on the young and the elderly population. 相似文献
79.
80.
田宝 《中国健康心理学杂志》2003,11(4):284-285,292
目的 探讨心理疗法对防治SARS的作用,方法 本文综合国内外心理疗法研究成果,提出了应对非典的心理处方:“接纳恐惧,顺其自然;平衡思维,端正认识;积极暗示,增强信心;切已体察,心理常态”;结果 从原理上解释其发生作用的机制,明确心理处方的实际操作,提出具体的步骤和要点,并对日常生活中的不妥做法进行了剖析。结论 采用心理疗法可增强抗击“非典”的信心及提高免疫功能。 相似文献