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Approximately 8–11% of all organ donors are classified by Public Health Service (PHS) as increased‐risk. The proportion of PHS increased‐risk donors is on the rise. At the University of Washington Medical Center, in 2014, the proportion of transplants from PHS increased‐risk donors was 28% of liver transplants and 23% of kidney transplants. Nationally, transplant providers have been reluctant to use organs from PHS increased‐risk donors because of concern for transmission of HIV, HCV, or HBV. There is also patient apprehension when these organs are being offered, and thus the discard rate of these otherwise good quality organs is high. Because of the organ shortage, preventing underutilization of such organs is essential. We provide data and considerations that should be used to guide the use of organs from PHS increased‐risk donors.  相似文献   
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Introduction

The aim of the study was to compare the K3 and K3XF systems (SybronEndo, Glendora, CA) after 1 and 2 uses by evaluating apical transportation, working length loss, and working time in a manikin model.

Methods

Mesial canals of 40 extracted first mandibular molars were instrumented. Radiographs taken after instrumentation with #25, #30, #35, and #40 files were superimposed on the preoperative image in both mesiodistal and buccolingual angulations. AutoCAD (Autodesk Inc, San Rafael, CA) was used to measure working length loss and apical transportation at 0, 0.5, and 1 mm from the working length (WL). The working time was measured. Group comparison was analyzed using post hoc Tukey honestly significant difference tests (P < .05).

Results

No significant differences were found in apical transportation, working length loss between K3 and K3XF systems, or between the number of uses. Significant differences were found when canal enlargement was performed to a #35–40 (P < .05). K3 instrumentation performed significantly faster (29.6 ± 15.4) than with the K3XF system (40.2 ± 17.7) (P < .05). No differences were observed in working time when comparing the number of uses.

Conclusions

K3 and R-phase K3XF rotary systems shaped curved root canals safely with minimal apical transportation, even up to a 40/04 file.  相似文献   
15.
A small cohort of 410 office workers (263 men and 147 women, ever employed) exposed to strong magnetic fields by three 12 kV transformers located beneath their first-floor office developed eight incident cancers over a 15 year exposure period. Only one cancer was ascertained in the 254 workers employed for less than 2 years, compared to seven cancer cases ascertained in the 156 workers employed for 2 years or more (p = 0.0057; Fisher's exact test). An analysis of linear trend of cancer incidence using average years employed as an exposure score was positive (p = 0.00337) with an odds ratio of 15.1 in workers employed over 5 years. A positive trend of cancer cases with duration of employment is seen for males and females separately and together (p < 0.05). For workers employed more than 2 years, the standardized cancer incidence ratio was 389 (95% confidence interval 156–801). Cumulative magnetic field exposure may be of etiologic importance in explaining the cancer incidence pattern in this cohort. © 1996 Wiley-Liss, Inc.  相似文献   
16.
子宫腔碘水加压法输卵管再通术的临床研究   总被引:6,自引:0,他引:6  
目的寻求一种简便快速、安全有效、经济实用,将造影诊断与输卵管再通治疗结合起来的新方法。方法应用双腔球囊胶管插入子宫腔,充盈球囊堵塞子宫颈内口,用助推器注入碘海醇充盈子宫腔及输卵管,电视动态观察实时点片,完成造影诊断。当发现输卵管阻塞时,用手助推加压,逐渐增高宫腔内压力,使阻塞输卵管被造影剂压力钝性开通。结果本组2698例,插管成功2685例。其中,原发不孕806例,继发不孕1868例,其他24例,输卵管阻塞3082支(右1561支、左1521支),占实有输卵管的59%,加压开通率为77.8%(2397/3082);通而不畅343支(右175支、左168支),加压开通率:93.9%(322/343),出现静脉逆流27例。除局部疼痛及少量阴道流血外,无严重并发症病及病死率。结论该法简便快速,安全有效,经济实用,将造影诊断与输卵管再通相结合,深受患者欢迎,值得推广应用。  相似文献   
17.
臧佳佳  高艳锋  韩书芝  平芬 《临床荟萃》2022,37(10):931-933
目的 探讨急性嗜酸性粒细胞肺炎的临床特点及诊疗方法。方法 对该患者行经气管肺部灌洗和肺组织活检,并给予糖皮质激素治疗,观察患者肺部影像学变化趋势。结果 经气管肺部灌洗和肺组织活检确诊后,给予糖皮质激素治疗,患者症状明显好转,胸部炎症渗出完全吸收。结论 急性嗜酸性粒细胞肺炎的临床症状不典型,可经气管肺部灌洗和肺组织活检确诊,且糖皮质激素治疗快速有效,一般预后良好。  相似文献   
18.
In this, the third paper of the series, the loudness of low-rate bursts of electrical pulses was measured as a function of the burst duration, in subjects implanted with the Nucleus® 24 cochlear implant system (three with straight and two with Contour™ electrode arrays). In order to help distinguish between the contributions of peripheral and more central effects, the ECAP was recorded to the individual pulses comprising the bursts, using the Neural Response Telemetry™ (NRT™) system. At a pulse rate of 250 pulses/s, the ECAP amplitude did not decrease greatly during the bursts: the mean reduction factor was 0.89. The time-constant for summation of the loudness contributions from the pulses comprising a burst was found to be larger than that associated with normal hearing. In addition, the first pulse of a pulse train was found to contribute much more to the overall loudness than did the subsequent pulses, although a corresponding difference was not observed in the ECAP recordings. These results establish a necessary connection between the essentially single-pulse model, developed in the fourth and fifth papers of the series, and the psychophysical data for pulse bursts, but they also have broader implications.  相似文献   
19.
目的:探讨急性脑血管病早期血糖升高对预后的影响。方法:回顾性分析56例急性脑血管病患者的临床资料,对早期血糖升高组(32例)和血糖正常者(24例)的预后进行比较。结果:急性脑血管病患者早期血糖升高组神经功能损害恢复程度分别为a组21.88%,b组28.13%,c组40.63%,d组9.36%,血糖正常组神经功能损害恢复程度分别为a组66.67%,b组16.67%,c组12.50%.d组4.16%。结论:急性脑血管病早期血糖升高的患者预后明显差于血糖正常的患者。  相似文献   
20.
The Experience Corps® program was designed to harness the social capital of an aging society to improve outcomes for public elementary schools. The objectives of this article are (1) to model the cost-effectiveness of the Experience Corps Baltimore using data from a pilot randomized trial, including costs, older adults’ health status, and quality of life and cost data from the Medical Expenditure Panel Survey, and (2) to describe the relationship between children experiencing increased expected lifetime earnings through improved educational attainment resulting from exposure to the Experience Corps Baltimore volunteers and the program’s costs and cost-effectiveness. On average, each quality adjusted life year (QALY) gained by older adults in Experience Corps Baltimore costs $205,000. The lower bound of the 95% confidence interval for the cost-effectiveness is $65,000/QALY. The upper bound is undefined as 15% of the simulations indicated no QALY improvements, If 0,3% of students exposed to the Experience Corps Baltimore changed from not graduating to graduating, the increased lifetime earnings would make the incremental cost-effectiveness ratio $49,000/QALY. If an additional 0,1% changed to graduating from high school, the program would be cost-saving. Using conservative modeling assumptions and excluding benefits to teachers, principals, and the surrounding community, the Experience Corps Baltimore appears expensive for the older adults’ health improvements, but requires only small long-term benefits to the target children to make the program cost-effective or cost-saving.  相似文献   
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