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目的:探讨改良大骨瓣联合软通道微创介入逐渐减压术治疗重型颅脑损伤的疗效。方法方便选择自2009年12月—2014年11月该院收治的重型颅脑损伤病例70例,随机分为改良组和对照组2组,每组35例,改良组施行改良大骨瓣联合软通道微创介入逐渐减压术,对照组按标准大骨瓣开颅、硬脑膜一次性全切开,对比分析两组的并发症发生率及预后。结果改良组发生迟发性颅内血肿、大面积脑梗塞及弥漫性脑肿胀等并发症9例(25.7%,9/35),预后良好者23例(65.7%,23/35),对照组发生并发症19例(54.3%,19/35),预后良好者14例(40.0%,14/35),两组并发症发生率和预后差异具有统计学意义(P<0.05)。结论改良大骨瓣联合软通道微创介入逐渐减压术治疗重型颅脑损伤,效果良好,显著降低死亡率。  相似文献   
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Biostatisticians play an important role in medical research. They are co-responsible for an appropriate and efficient study design, they are involved in monitoring the study conduct, they plan and perform the data analysis, and they are involved in interpreting and publishing the results. However, how are the biostatisticians prepared for their tasks and responsibilities? Graduate programs in biostatistics are being offered, but some practicing biostatisticians completed their studies in a mathematical or epidemiological program, or obtained their degree in subject-specific fields (such as medicine or biology). Therefore, the expertise and the competencies can vary widely between the individual biostatisticians, also depending on the application field. In this article, focusing on European and US practices, we discuss the required professional expertise for the main areas of applications in the medical field as well as the necessary soft skill competencies of a biostatistician.  相似文献   
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Donor site morbidity following radial forearm flap (RFF) harvest remains a controversial issue. The aim of this meta-analysis was to answer the question “Are the range of wrist movements (range of motion, ROM) and hand strength affected after RFF harvesting?” The PubMed, Embase, Scopus, and Cochrane Library electronic databases were systematically searched (to December 2019). Self-controlled studies evaluating hand biomechanics after RFF harvest were included. Weighted mean differences with 95% confidence intervals were calculated using the random-effects model. The outcome variables were ROM, forearm movements, grip, and pinch strengths. Thirteen studies involving a total of 335 patients were included. With the exception of grip strength and supination, which showed statistically significant reductions of about 2.40 kg and 2.86° (P < 0.05), all other ROM, forearm movements, and pinch strengths showed an insignificant difference when the operated hand was compared to the non-operated hand (P > 0.05). Regression analysis showed that the method of donor site closure and size of the donor site defect had an insignificant impact on hand biomechanics. This study confirms the lack of discernible biomechanical morbidity after RFF transfer. The minimal reduction in hand biomechanics after RFF is considered to be clinically negligible.  相似文献   
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本文回顾了Er:YAG激光活化根管冲洗技术的最新研究进展,包括光子诱导光声流(photon initiated photoacoustic streaming,PIPS)技术和冲击波增强发射光声流(shock wave enhanced emission photoacoustic streaming,SWEEPS)技术,探讨Er:YAG激光预处理桩道的原理、优点以及对纤维桩粘接强度的影响,以期为临床选择适宜的桩道处理方法提供新思路。  相似文献   
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The lung is the preferred site of metastasis from soft tissue sarcoma (STS). This systematic review aims to evaluate the outcomes of stereotactic body radiotherapy (SBRT) and metastasectomy (MTS) for the treatment of lung metastases from STS. A systematic review was carried out according to the PRISMA protocol. PubMed, Medline, EMBASE, Cochrane Library, Ovid and Web of Knowledge databases were searched for English-language articles to December 2018 using a predefined strategy. Retrieved studies were independently screened and rated for relevance. Data were extracted by two researchers. In total, there were 1306 patients with STS: 1104 underwent MTS and 202 had SBRT. The mean age ranged from 40 to 55.8 years in the MTS group and from 47.9 to 64 years in the SBRT group. The cumulative death rate was 72% (95% confidence interval 59–85%) in the MTS group and 56% (38–74%) in the SBRT group. The cumulative mean overall survival time was 46.7 months (36.4–57.0%) in the MTS group and 47.6 months (33.7–61.5%) in the SBRT group. The cumulative rate of patients alive with disease was 5% (2–9%) in the MTS group and 15% (6–36%) in the SBRT group. Finally, the cumulative rate of patients alive without disease in the two groups was 19% (9–29%) and 20% (10–50%), respectively. Our study showed that local treatment of pulmonary metastases from STS with SBRT, compared with surgery, was associated with a lower cumulative overall death rate and similar overall survival time and survival rates without disease. By contrast, SBRT was associated with a higher survival rate with disease than MTS. Large randomised trials are necessary to confirm these findings and to establish whether SBRT may be a reliable option for early stage disease.  相似文献   
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文题释义:跑:跑是双脚交替接触地面的周期性运动,但跑有一个双脚都离开地面的腾空期。幼儿在 1 岁多开始学习跑步,最初是走跑结合的移动方式,由于身体发育不完善,下肢力量弱,平衡能力差,容易摔倒;到 2.5岁,幼儿跑步的腾空阶段明显;到 6岁,早期跑步的特点基本消失。 着地方式:指的是人体在跑步着地阶段足部接触地面的方式,一般分为3种方式:分别为足跟着地(fore foot strike),跟骨先接触地面;全足着地(mid foot strike),全脚掌着地,即足跟与前足同时接触地面;前足着地(rear foot strike):前足部首先接触地面。 背景:成年人跑步着地方式一直是国内外学者研究的重点,而幼儿跑步的着地方式也是不容忽视的内容。 目的:运用生物力学方法探究幼儿在跑步过程中,不同着地方式下的运动学和动力学指标的差异,为幼儿正确的跑步着地方式提供科学依据。 方法:在北京市海淀区某公立幼儿园中随机抽取幼儿74名,按年龄分为3岁组、4岁组、5岁组,采用BTS红外动作捕捉系统、Kistler三维测力台和VIXTA录像解析系统同步采集幼儿跑步过程中不同着地方式下的运动学、动力学数据;运用Anybody 5.2仿真建模软件计算下肢肌肉力量指标。试验前向受试者父母详细解释并签署知情同意书,试验方案符合北京师范大学的相关伦理要求。 结果与结论:①3岁组全足着地的比例最高,足跟着地的比例最低,5岁组全足着地的比例最低,足跟着地的比例最高;前足着地者的蹬伸时间大于足跟着地(P < 0.01)和全足着地(P < 0.05);②着地时刻,踝屈曲角度足跟着地者大于前足着地(P < 0.01)和全足着地者(P < 0.05),全足着地者大于前足着地(P < 0.05);前足着地者髋内收-外展角度、最大髋内收-外展角、髋内-收外展的关节变化量及最大膝内收-外展角速度大于足跟着地(P < 0.01)和全足着地者(P < 0.05);前足着地者的踝屈伸最小值大于足跟着地者(P < 0.05),而最大髋内收-外展角速度小于足跟着地者(P < 0.05);③足跟着地和全足着地者的腓骨短肌、腓骨长肌、第三腓骨肌的肌力大于前足着地者(P < 0.05),前足着地者的股中间肌、股外侧肌下束、股外侧肌上束、股内侧肌下束、股内侧肌上束、股内侧肌中束肌力均大于足跟着地(P < 0.01)和全足着地者(P < 0.05);④结果提示:在3-6岁阶段,幼儿多采用足跟或全足着地模式进行奔跑,以满足自己在跑步过程的稳定性,随着年龄的增长,逐渐出现前足着地方式的跑步模式;前足着地能够动用更多髋关节和膝关节额状面的运动来维持人体运动中的稳定,足跟着地和全足着地能够动用更多的小腿前侧和后侧的肌力,而前足着地动用更多的大腿前侧肌力。 ORCID: 0000-0002-8337-3931(赵盼超) 中国组织工程研究杂志出版内容重点:组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程  相似文献   
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