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排序方式: 共有8769条查询结果,搜索用时 31 毫秒
41.
Effect of Population Aging on the International Organ Donation Rates and the Effectiveness of the Donation Process 总被引:2,自引:2,他引:0
N. Cuende J. I. Cuende J. Fajardo J. Huet M. Alonso 《American journal of transplantation》2007,7(6):1526-1535
This study analyzed the effect of population aging on organ donation for transplants in 43 countries and on the effectiveness of the donation process by comparing the results between Spain and the United States. The percentage of the population aged 65 or over accounted for 33% of the difference in the donation rates between the countries and for 91% of the variation in the rates after age adjustment. However, the level of aging of the Spanish (16.5%) and American (12.3%) populations failed to account for the percentages of deceased donors 65 or over (28% vs. 10%), due to the different age-specific donation rates, much higher in Spain above 50 years. These differences lead to a higher effectiveness of the process in the United States (3.1 transplanted organs per donor vs. 2.5 in Spain), though at lower rates of transplant per million population (73 vs. 87). We conclude that older populations have a greater donation potential as donation rates are strongly associated with population aging. It should therefore be mandatory to adjust donation rates for age before making comparisons. Additionally, effectiveness decreases with older donors, so age should be considered when establishing standards relating to organ donation and effectiveness of the process. 相似文献
42.
目的研究基于计算机模糊智能识别运算的语言障碍诊治仪ZM2.1(简称:语言障碍ZM2.1)对失语流利性检测的效度与信度。方法采用ABC法和语言障碍ZM2.1两种方法分别对58例失语症患者进行流利性检测,两种方法检测间隔时间在3d之内。结果ABC法流利性内部一致性检验,整体克朗巴赫α系数(Cronbach α)=0.8732;语言障碍ZM2.1平均语速和ABC法流利性总分有正相关性趋势,Spearman系数为0.721(P〈0.01);语言障碍ZM2.1检测流利性的准确度为81%(以XABC法为标准);测得两者流利性结果一致性良好(P〈0.01)。结论语言障碍ZM2.1在评价失语症流利性方面具有良好的信度和效度,可用于临床进行失语症的流利性检测。 相似文献
43.
计算机导航下空心钉内固定治疗股骨颈骨折 总被引:7,自引:2,他引:5
目的 探讨计算机导航技术在股骨颈骨折空心钉内固定治疗中的应用,为骨折内固定提供一个新的手术技术。方法 8例股骨颈骨折,术前Garden分型为Ⅰ型3例,Ⅱ型4例,Ⅲ型1例。术中牵引复位后,通过一次C臂机透视正侧位,即可在计算机导航下完成内固定。术后常规透视复查。结果 8例病例全部在导航下完成空心钉的内固定,平均透视时间为15s,远远少于常规内固定所须的时间。结论 计算机导航技术成功应用于空心钉内固定手术,有效减少了手术中X射线的辐射,同时提高了手术的精度,可避免机械引导器的误差,随时反映操作的过程,使手术过程更方便、直观。 相似文献
44.
计算机辅助导航骨科手术及医用机器人技术在创伤骨科的应用 总被引:6,自引:0,他引:6
本文介绍了计算机辅助导航骨科手术(CAOS)及医用机器人技术在创伤骨科应用中的主要进展、当前在临床应用中存在的主要问题和相关对策,并对其未来的发展趋势进行了预测,同时简要介绍了北京积水潭医院创伤骨科在计算机辅助导航骨科手术及医用机器人技术方面的研究进展。当前骨科手术导航定位所应用的医学图象导引系统已经由使用单一的C型臂、CT等传统影像设备向应用三维C型臂、多模态图像处理系统等新型影像设备转变,基于多模态图像的导航系统将有可能成为导航手术的主流。医用机器人已经在自动化程度和人机交互模式方面,有了长足进展,摆脱了原有工业机器人的结构模式。医学图像后处理技术及其它相关信息技术极大地丰富了导航和机器人外科,只有在不断完善光学定位技术的同时,加大对其它定位方法的研究,才能够提高定位精度;要对相关设备进行开放式结构设计,使不同导航系统的注册软件能够互相兼容,手术器械能够通用,降低设备成本。骨科医生要正确认识计算机辅助导航骨科手术及医用机器人技术,在充分了解CAOS的技术特点、基本原理、操作程序的基础上,对要实施的手术具有深刻的理解,才能开展CAOS手术。目前,迫切需要建立CAOS技术标准、临床适应证和手术操作规范,进行CAOS产品之间的技术比较和评估,便于医生选择合适的CAOS产品。伴随快速发展的信息技术,数字化手术室、智能化微创导航手术系统、医用机器人辅助的远程医疗将有可能成为未来CAOS技术的主要组成部分。 相似文献
45.
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47.
Objective
Participation in evidenced‐based arthritis self‐management programs (SMPs) has not been well documented. The purpose of this study was to investigate the participation rate and participant characteristics in a closed cohort of subjects in a geographic region where arthritis SMPs have been offered multiple times and continuously for 2 decades.Methods
Data were from osteoarthritis (OA) and rheumatoid arthritis subjects participating in the Arthritis, Rheumatism, and Aging Medical Information System (ARAMIS) who resided in the San Francisco (SF) Bay area who had responded to questions about ever participating in an SMP. Differences between participants and nonparticipants were examined by t‐tests and chi‐square tests.Results
Questions added to the Health Assessment Questionnaire were returned by 1,176 patients; 618 resided in the SF Bay area. Of the SF Bay area sample, 41.9% had participated in an SMP. Small group SMPs, which had been offered multiple times, in diverse settings, continuously over the past 2 decades, were attended by the highest proportion (28%) of participants. Characteristics of participants and nonparticipants in the SF Bay area were similar (~70 years old, 15 years of education, and the majority had OA [~72%]). However, a higher proportion of participants were white (88% versus 82%; P = 0.046) and female (82% versus 73%; P < 0.05).Conclusion
When arthritis SMPs were offered multiple times in diverse settings and continuously over many years, >40% of the cohort was reached. More research is needed with larger samples and different geographic regions to identify participation rates in more diverse populations. 相似文献48.
A.J. Greenshaw 《Brain research bulletin》1986,16(5):759-761
A BASIC computer program is described which is useful for calculating filling concentrations for ALZET osmotic mini-pumps employed in studies of chronic drug and hormone administration. After the user has entered the required daily dose, the pump parameters and the animals' weights, the program gives the following information: The total quantity of the drug or hormone required for the experiment; the minimum volume and concentration of solution, allowing a 10% margin for error, to serve as a standard that, when diluted, will fill all pumps in the experiment; individual volumes of this solution that, when diluted to a constant volume will yield the required concentrations to fill each of the respective pumps. Use of this program will ensure reliably accurate and very rapid preparations of solutions for mini-pump use. 相似文献
49.
Thomas Ngele Uwe Klose Wolfgang Grodd Karsten Voigt Fridtjof Nüsslin 《Journal of magnetic resonance imaging : JMRI》1995,5(4):416-420
An RF excitation pulse for three-dimensional (3D) time-of-flight (TOP) MR angiography (MRA) with a nonlinear excitation profile was numerically calculated under the condition of uniform vessel signal across the excitation volume (slab), and the superiority of the optform pulse as compared with conventional RF pulses and TONE pulses was demonstrated. For this purpose we acquired MRA of the lower leg and of the carotid and vertebral arteries in a 30-year-old healthy volunteer. Although the flow velocity ranges in these two anatomic locations are different by about a factor of 10, in both cases the corresponding optform pulse provided the best signal homogeneity at the highest level. 相似文献
50.