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51.
目的:探讨复合负压吸引的外固定钢板治疗四肢开放性骨折的应用价值。方法:选择2014年1月到2017年1月到我院诊治的胫腓骨中下段开放性骨折患者共68例为研究对象,根据随机信封抽签原则分为观察组与对照组,每组34例。对照组给予负压封闭引流(vacuum sealing drainage,VSD)的常规外固定钢板治疗,观察组给予复合负压吸引的外固定钢板治疗,记录和比较围手术期严重并发症的发生情况、手术时间、骨折愈合时间、临床疗效和创口愈合情况。结果:两组患者都完成手术,围手术期并无严重并发症发生。观察组的手术时间与骨折愈合时间分别为38.24±8.16 min和8.83±1.01周,均明显少于对照组(49.50±9.87min和12.23±0.91周)(P0.05)。术后3个月,观察组和对照组的疗效优良率分别是97.1%、82.4%,观察组明显高于对照组(P0.05);观察组的创口甲级愈合28例,乙级愈合6例,丙级愈合0例;对照组甲级愈合21例,乙级愈合8例,丙级愈合5例,观察组创口愈合情况明细优于对照组(P0.05)。结论:复合负压吸引的外固定钢板治疗四肢开放性骨折能明显缩短手术时间,促进骨折愈合,提高创口愈合质量,提高临床疗效。 相似文献
52.
Mohsen Koohestani Richard Perdriau Yves Le Dréan Mauro Ettorre Maxim Zhadobov 《Bioelectromagnetics》2020,41(5):369-381
This paper presents the design of a resonant system for in vitro studies to emulate the exposure of a monolayer of cells to a wireless power transfer system operating at 13.56 MHz. The design procedure targets a system, which maximizes the specific absorption rate (SAR) uniformity on the plane where the layer is cultured, as well as SAR efficiency (defined as SAR over the input power), within the size constraints of a standard incubator. Three resonant wireless power transfer systems with different commonly used loop/coil geometries (cylindrical with circular and square cross-sections and annular) were compared with assess the configuration maximizing the considered design criteria. The system performance in terms of reflection and transmission coefficients, as well as generated E- and H-fields, was characterized numerically and experimentally inside the incubator. Moreover, SAR was computed at the monolayer level. The system equipped with cylindrical coils with square cross-sections led to a high electromagnetic field uniformity in in vitro biological samples. In particular, the uniformities in E and SAR at the layer level were within 7.9% and 5.5%, respectively. This was achieved with the variation in H below the usually considered ±5% limit. © 2020 Bioelectromagnetics Society 相似文献
53.
目的:探讨体外反搏联合言语训练治疗脑性瘫痪并语言发育迟缓儿童的临床疗效。方法:选择2015年12月至2017年12月在上海市儿童医院康复科普通门诊确诊的脑瘫并语言发育迟缓患儿52例,按照随机数字表法将其随机分为治疗组和对照组,每组26例。对照组仅给予言语训练治疗,治疗组给予体外反搏联合言语训练治,以4周1个疗程,两组均治疗3个疗程。治疗前后,采用中国康复研究中心汉语版儿童语言发育评定法s-s法、Gesell发育评分法评价和比较患儿言语发育商和认知发育商的变化。结果:治疗后,两组言语发育商和认知发育商均显著高于治疗前,且治疗组言语发育商和认知发育商均显著高于对照组,差异均有统计学意义(均P0.01)。结论:体外反搏联合言语训练较单纯言语训练可更有效改善脑瘫并语言发育迟缓患儿的言语发育和认知发育。 相似文献
54.
JNK is one of the key molecules regulating cell differentiation and migration in a variety of cell types, including cerebral cortical neurons. MUK/DLK/ZPK belongs to the MAP kinase-kinase-kinase class of protein kinases for the JNK pathway and is expressed predominantly in neural tissue. We have determined the expression pattern of MUK/DLK/ZPK and active JNK in the cerebellum at different stages of postnatal development. Quantitative analysis by Western blotting has showed that high expression levels of MUK/DLK/ZPK and active JNK are maintained during the postnatal development of the cerebellum, and that these levels decrease in the adult cerebellum. Immunohistochemical staining has revealed, however, that their distribution in the developing cerebellum is considerably different. Although active JNK is highly concentrated in the premigratory zone of the external germinal layer (EGL), high expression of MUK/DLK/ZPK has been observed in the molecular layer and in the premigratory zone. Neither the active JNK nor MUK protein has been detected in the proliferative zone of the EGL. These observations suggest that during the postnatal development of the cerebellum, the MUK-JNK signaling pathway contributes to the regulation of granule cell differentiation and migration; further, the activity of MUK/DLK/ZPK is tightly regulated by posttranslational mechanisms and by its expression level.This work was supported by a Ishizu Shun memorial scholarship and grants from the Ministry of Education, Culture, Sports, Science and Technology of Japan. 相似文献
55.
Ten laboratories in an external quality assurance scheme used the same assay to measure anti-müllerian hormone concentration (Beckman Coulter Gen II) and received twenty serum samples distributed over a 15 month period. The mean bias for all results was only ?0.089%, but there was large coefficient of repeatability of 38.8% (sample bias ranged from ?37.9% to +54.7%). While each laboratory showed good reproducibility, there was a wide range of average values relative to the consensus value from ?24.0% to +22.7%. This between-laboratory variability suggests clinicians should use the same laboratory to avoid problems with result interpretation. 相似文献
56.
随着超声技术的发展和对心脏疾病治疗研究的深入,超声技术在心脏疾病治疗领域中的应用逐步成为研究热点。其中,体外超声作为一种无创物理疗法,尤为受到研究者们的关注。本文介绍了近年来体外超声在心脏疾病治疗中的应用进展,并对其存在的问题和发展前景进行了探讨。 相似文献
57.
Whole-body cryotherapy (WBC) involves exposing minimally dressed participants to very cold air (injecting liquid nitrogen with temperature −195 °C), either in a specially designed chamber (cryo-chamber) or cabin (cryo-cabin), for a short period of time. The aim of this study was to examine the actual temperature of the air in the cryo-cabin at different locations throughout the cabin by using human subjects and a manikin. Additionally, we monitored skin temperature before and for 60 min after the cryo-cabin session. Twelve subjects completed one 3 min cryo-cabin session. Temperature next to the skin was assessed during the session, while the skin temperature was monitored before, 3 min after and every 10 min for 60 min after completing the session. There was a statistically significant interaction (time×position) for temperature among the different body parts during the WBC, and for skin temperature among different body parts after the cryo-cabin session. Statistically significant time effects during and following cryo-cabin session were present for all body parts. We showed that actual temperature in the cryo-cabin is substantially different from the one reported by the manufacturer. Thermal response after cryo-cabin session is similar to response observed after cryo-chamber cold exposure reported in previously published studies. This could be of great practical value as cryo-cabins are less expensive and easier to use compared to cryo-chambers. 相似文献
58.
Defining a subject-specific model of the human body is required for motion analysis in many fields, such as in ergonomics and clinical applications. However, locating internal joint centers from external characteristics of the body still remains a challenging issue, in particular for the spine. Current methods mostly require a set of rarely accessible (3D back or trunk surface) or operator dependent inputs (large number of palpated landmarks and landmarks-based anthropometrics). Therefore, there is a need to provide an alternative way to estimate joint centers only using a limited number of easily palpable landmarks and the external back profile. Two methods were proposed to predict the spinal joint centers: one using only 6 anatomical landmarks (ALs) (2 PSIS, T8, C7, IJ and PX) and one using both 6 ALs and the external back profile. Regressions were established using the X-ray based 3D reconstructions of 80 subjects and evaluated on 13 additional subjects of variable anthropometry. The predicted location of joint centers showed an average error 9.7 mm (±5.0) in the sagittal plane for all joints when using the external back profile. Similar results were obtained without using the external back profile, 9.5 mm (±5.0). Compared to other existing methods, the proposed methods offered a more accurate prediction with a smaller number of palpated points. Additional methods have to be developed for considering postures other than standing, such as a sitting position. 相似文献
59.
60.
Ryan K. Chung Angela M. Wood Michael J. Sweeting 《Biometrical journal. Biometrische Zeitschrift》2019,61(2):454-466
To help prevent anaemia, it is a requisite for blood donors to undergo a haemoglobin test to ensure levels are not too low before donation. It is therefore important to have an accurate testing device and strategy to ensure donors are not being inappropriately bled. A recent study in blood donors used a selective testing strategy where if a donor's haemoglobin level is below the level required for donation, then another reading is taken and if this occurs again, a third and final reading is used. This strategy can reduce the average number of readings required per donor compared to taking three measurements for all donors. However, the final decision‐making measurement will on average be higher than a single measurement. In this paper, a selective testing strategy is compared against other strategies. Individual‐level biases are derived for the selective strategy and are shown to depend on how close a donor's true haemoglobin level is to the donation threshold and the magnitude of error in the testing device. A simulation study was conducted using the distribution of haemoglobin levels from a large donor population to investigate the effects different strategies have on population performance. We consider scenarios based on varying the measurement device bias and error, including differential biases that depend on the underlying haemoglobin level. Discriminatory performance is shown to be affected when using the selective testing strategies, especially when measurement error is large and when differential bias is present in the device. We recommend that the average of a number of readings should be used in preference to selective testing strategies if multiple measurements are available. 相似文献