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41.
目的:探讨3D打印技术辅助前侧微创入路手术治疗不稳定型骨盆骨折的临床疗效及安全性。方法:选择2014年8月到2017年2月在我院诊治的骨盆骨折患者78例作为研究对象,按照随机信封抽签原则分为观察组与对照组,每组各39例。对照组采用常规X线与CT进行手术设计,观察组采用3D打印技术进行手术设计,两组都给予前侧微创入路手术治疗,比较两组的手术时间、切口长度、骨折愈合时间、术中出血量、术中和术后并发症的发生情况及术后3个月的骨盆功能优良率。结果:所有患者都完成手术,无术中严重并发症发生,两组手术时间及切口长度对比差异无统计学意义(P0.05)。对照组的骨折愈合时间、术中出血量显著高于观察组(P0.05)。观察组术后并发症的发生率(5.1%)显著低于对照组(25.6%)(P0.05),术后3个月的骨盆功能优良率(97.4%)显著高于对照组(74.4%)(P0.05)。结论:与常规X线与CT前侧微创入路手术治疗比较,3D打印技术辅助前侧微创入路手术治疗不稳定型骨盆骨折可为患者提供安全、有效、个性化的治疗,减少术后并发症的发生,改善患者的骨盆功能。  相似文献   
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The use of microsatellite DNA markers for soybean genotype identification   总被引:36,自引:0,他引:36  
Conventional morphological and pigementation traits, as well as disease resistance, have been used to distinguish the uniqueness of new soybean cultivars for purposes of plant variety protection. With increasing numbers of cultivars and a finite number of conventional characters, it has become apparent that such traits will not suffice to establish uniqueness. The objective of this work was to provide an initial evaluation of microsatellite or simple-sequence-repeat (SSR) DNA markers to develop unique DNA profiles of soybean genotypes. Microsatellites are DNA sequences such as (AT) n /(TA) n and (ATT) n /(TAA) n that are composed of tandemly repeated 2–5-basepair DNA core sequences. The DNA sequences flanking microsatellites are generally conserved allowing the selection of polymerase chain reaction (PCR) primers that will amplify the intervening SSR. Variation in the number of tandem repeats, n, results in PCR product length differences. The SSR alleles present at three (AT) n /(TA) n and four (ATT) n /(TAA) n loci were determined in each of 96 diverse soybean genotypes. Between 11 and 26 alleles were found at each of the seven loci. Only two genotypes had identical SSR allelic profiles and these had very similar pedigrees. The gene diversity for the seven markers averaged 0.87 for all 96 genotypes and 0.74 for a subset of 26 North American cultivars. These are much higher than soybean gene diversity values obtained using RFLP markers, and are similar to the average values obtained for human microsatellite markers. SSR markers provide an excellent complement to the conventional markers that are currently used to characterize soybean genotypes.  相似文献   
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Screen printing technology provides a cheap and easy means to fabricate disposable electrochemical devices in bulk quantities which are used for rapid, low-cost, on-site, real-time and recurrent industrial, pharmaceutical or environmental analyses. Recent developments in micro-fabrication and nano-characterization made it possible to screen print reproducible feature on materials including plastics, ceramics and metals. The processed features forms screen-printed disposable biochip (SPDB) upon the application of suitable bio-chemical recognition receptors following appropriate methods. Adequacy of biological and non-biological materials is the key to successful biochip development. We can further improve recognition ability of SPDBs by adopting new screen printed electrode (SPE) configurations. This review covers screen-printing theory with special emphasis on the technical impacts of SPE architectures, surface treatments, operational stability and signal sensitivity. The application of SPE in different areas has also been summarized. The article aims to highlight the state-of-the-art of SPDB at the laboratory scale to enable us in envisaging the deployment of emerging SPDB technology on the commercial scale.  相似文献   
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目的:探讨基于医疗数据信息集成系统的3D打印技术在治疗肺癌中的应用。方法:2014年10月~2015年10月收治的符合肺癌临床路径,进入医疗数据信息集成系统,并接受320排螺旋CT扫描三维重建,3D打印出实体1:1大小的患侧肺血管及肺病灶模型,术前制定手术方案且模拟手术过程的42例非小细胞肺癌(NSCLC)患者,经电视胸腔镜应用内镜缝合切割器切除病灶,术中快速冰冻切片明确诊断,行肺段切除术,肺叶切除术。观察术中肺血管与3D打印符合程度。记录手术时间、术中出血量、切除淋巴结数量、有无术中死亡、病理结果、并发症、引流时间和引流量及术后生存情况。结果:术中证实95%以上的肺血管可被3D打印出来。手术时间(51.4±18.1)min,术中出血量(40.2±20.3)mL。切除淋巴结(7.1±2.8)枚。无术中死亡。术后病理回报示肺鳞癌13例,肺腺癌29例。病理分期:T1aN0M0 12例,T1aN1M0 10例,T1bN0M0 3例,T1bN1M0 3例,T2aN0M0 2例,T2aN1M0 12例。术后患者无严重并发症,其中肺感染6例、肺膨胀不全6例、房颤5例,所有患者经积极后痊愈;术后引流时间(3.0±1.2)d,引流量(200.7±66.1)mL/d。42例随访2~12个月,中位随访时间8.0月,40例无瘤生存,术后6个月发生转移脑转移2例,分别于术后7和10个月死亡。结论:基于医疗数据信息集成系统的3D打印技术可以应用于肺癌手术。  相似文献   
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目的:揭示3D生物打印产业技术研发态势和专利布局,以期为相关机构提供竞争情报,为行业发展提供数据支撑。方法:基于3D生物打印领域产业调研和技术分解,构造检索式获取数据,多维度量化分析领域专利。结果:3D生物打印产业发展可分为孕育期、萌芽期和高速发展期;该产业集中度较低,处于分散竞争阶段;申请人多依据地缘因素选择合作对象,合作方之间多为不同类型的机构;中国申请人的专利申请量占全球的比重已接近50%,但美国申请人的专利篇均被引频次仍远超中国;美国申请人更关注海外市场。结论:3D生物打印产业尚未形成规模效应,有必要整合业内资源,打造产业集群;中、美两国在该产业都具有优势地位,中国亟待加强海外专利布局;综合权衡专利数量和质量,美国申请人的专利竞争力仍高于中国,中国需培育更多核心专利。  相似文献   
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Acoustic-based monitoring has proved useful for many birds and seems promising for the endangered red-crowned crane. However, its validity in crane conservation is unclear in the absence of knowledge concerning the long-term stability of pair-specific duets. The red-crowned crane is monogamous and long-lived, with stable pair bonding both within and between years. Pair mates perform loud duets—a succession of male and female calls emitted with definite temporal coordination. We examined the stability of duets for five captive pairs over five years (2003–2007) on the basis of analysis of the syllables within the duets. MANOVA showed that the effect of pair identity on syllable characteristics was always stronger than the effect of the year of recording. Cross-validation of duets from 2004, 2005, 2006, and 2007 with discriminant analysis (DFA) functions derived, respectively, from pooled samples from 2003, 2003–2004, 2003–2005, and 2003–2006 resulted in comparably high percentages of correct classification into pairs. The pairs could be reliably identified by their duets and pair-specific differences in syllable characteristics were stable with time. These data suggest acoustic monitoring is a feasible alternative to more invasive methods of identification.  相似文献   
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