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61.
目的建立完善的鼓膜-听骨链模型,利用有限元初步探讨镫骨前、后脚骨质缺损对听力传导的影响。方法实验数据源于对一名无中耳病史的成年男性左侧颞骨进行Micro-CT扫描,在医学影像处理软件Mimics上进行三维重建,利用Geomagic形成需要的曲面,最后在SolidWorks上将成型的鼓膜-听骨链模型进行切割组装,建立正常听骨链模型以及镫骨前、后脚骨质缺损模型,利用模型分析骨质缺损对听力传导的影响。结果建立的鼓膜-听骨链模型镫骨足板频振曲线符合相关文献报道,在镫骨前、后脚骨质缺损病理模型下,曲线与正常中耳模型曲线接近。结论利用多软件综合处理,可建立可信度较高的中耳听骨链模型;有限元模拟分析结果显示,镫骨前、后脚缺损部分骨质,未对听力传导产生明显影响。  相似文献   
62.
PURPOSE: To describe the clinic-pathological analysis of the visually significant opacification of the Cirrus International Hydroflex foldable hydrophilic acrylic intraocular lens (IOL) (model SC600-2, Medical Developmental Research Inc., Clearwater, Florida) and to highlight that this IOL is the same model as the Acryflex SC600-2 IOL, by the same manufacturer. METHODS: Retrospective review of five eyes of four patients with opacification of their Cirrus International Hydroflex foldable hydrophilic acrylic IOLs (model SC600-2) after uncomplicated phacoemulsification and IOL implantation. Two IOLs were explanted from two patients 14 to 24 months after initial implantation. Each explanted lens was divided into equal halves, one half for scanning electron microscopy (SEM) study and the other half for transmission electron microscopy (TEM) examination. SEM and TEM samples were also subjected to energy dispersive X-ray analysis (EDX). RESULTS: The IOL opacification was detected 14 to 24 months after uncomplicated phacoemulsification and IOL implantation. EDX analysis showed that the crystals contained calcium and phosphorus, presumably calcium phosphate. CONCLUSIONS: The Cirrus International Hydroflex foldable hydrophilic acrylic IOL (model SC600-2) is associated with opacification, that appeared worse centrally than peripherally. This is the same model as the Acryflex SC600-2 IOL, made by the same manufacturer. The opacification consists of calcium and phosphate.  相似文献   
63.
??OBJECTIVE To study preliminarily the cadmium absorption and accumulation in Ligusticum Wallichii to provide a scientific basis for solving the problem of cadmium excess. METHODS The aboveground and underground parts of Ligusticum Wallichii in different growth periods and the rhizosphere soil were collected from Aoping Town, Pengzhou City and Yongshou Town, Meishan City. The cadmium content was determined, and the enrichment coefficient and transfer coefficient were calculated. RESULTS The average cadmium content in the underground part was 77.21% higher than that in the aboveground part. The cadmium enrichment coefficients and cadmium transfer coefficients of different parts were both greater than 0.5, and the enrichment coefficient of the underground part was 64.75% higher than the aboveground part. CONCLUSION Ligusticum Wallichii has a certain capacity to absorb and transfer cadmium, and most cadmium is enriched in the medicinal roots.  相似文献   
64.
65.
目的 构建Trappin-2的真核表达体系,初步探讨Trappin-2对HaCaT细胞及银屑病跨膜模型增殖的影响.方法 采用DNA重组技术构建Trappin-2的表达载体pIRES2-EGFP-Trappin-2,通过脂质体法转染入宫颈癌HeLa细胞.将Trappin-2高表达上清加入HaCaT细胞及银屑病跨膜模型中,通过3H-TdR掺入法、MTT法、流式细胞术及组化染色Ki67检测对增殖的影响.结果 Trappin-2作用后MTY和cpm值变化率显示Trappin-2可抑制HaCaT细胞的代谢与DNA合成,同时可使HaCaT细胞G2 S期细胞比例下降,而G1期细胞比例增加.Trappin-2可下调银屑病皮损Ki67表达水平.结论 成功将Trappin-2基因转染HeLa细胞,并进行有效表达,初步证实Trappin-2具有抑制HaCaT细胞及银屑病跨膜模型增殖的特性.  相似文献   
66.
INTRODUCTIONFluorescence imaging (FI) with indocyanine green (ICG) is increasingly implemented as an intraoperative navigation tool in hepatobiliary surgery to identify hepatic tumours. This is useful in minimally invasive hepatectomy, where gross inspection and palpation are limited. This study aimed to evaluate the feasibility, safety and optimal timing of using ICG for tumour localisation in patients undergoing hepatic resection.METHODSFrom 2015 to 2018, a prospective multicentre study was conducted to evaluate feasibility and safety of ICG in tumour localisation following preoperative administration of ICG either on Day 0–3 or Day 4–7.RESULTSAmong 32 patients, a total of 46 lesions were resected: 23 were hepatocellular carcinomas (HCCs), 12 were colorectal liver metastases (CRLM) and 11 were benign lesions. ICG FI identified 38 (82.6%) lesions prior to resection. The majority of HCCs were homogeneous fluorescing lesions (56.6%), while CLRM were homogeneous (41.7%) or rim-enhancing (33.3%). The majority (75.0%) of the lesions not detected by ICG FI were in cirrhotic livers. Most (84.1%) of ICG-positive lesions detected were < 1 cm deep, and half of the lesions ≥ 1 cm in depth were not detected. In cirrhotic patients with malignant lesions, those given ICG on preoperative Day 0−3 and Day 4−7 had detection rates of 66.7% and 91.7%, respectively. There were no adverse events.CONCLUSIONICG FI is a safe and feasible method to assist tumour localisation in liver surgery. Different tumours appear to display characteristic fluorescent patterns. There may be no disadvantage of administering ICG closer to the operative date if it is more convenient, except in patients with liver cirrhosis.  相似文献   
67.
蓝布正补血作用的实验研究   总被引:1,自引:0,他引:1  
目的:探讨蓝布正的补血作用。方法:建立小鼠急性失血性"血虚"模型,采用蓝布正不同剂量水煎液灌胃治疗,治疗后第9天测定Hb和RBC值。结果:蓝布正高、中、低三个剂量组的Hb含量和RBC值与"血虚"开始治疗时相比,明显升高(P〈0.01),并高于模型组(P〈0.01),但低于当归阳性对照组(P〈0.05或P〈0.01)。结论:蓝布正具有补血效果。  相似文献   
68.
叶天士络病学说初探   总被引:14,自引:0,他引:14  
对散见于《临证指南医案》一书中有关“络病”的论述,进行了系统的整理和总结。强调了叶氏关于新病、久病皆可入络的观点,总结了络病当分气血,脏腑的辨证原则,概述了络病当以通络为主的治疗原则,介绍了络病通络的具体方法和有关病案。  相似文献   
69.
生后早期大鼠下丘脑核团发育的形态学变化   总被引:2,自引:0,他引:2  
目的 了解生后早期大鼠下丘脑核团发育情况 ,为相应行为变化提供解释证据。方法 采用 10、13、16d龄雄性大鼠各 10只 ,制作火棉胶连续切片 ,应用计算机分析系统对下丘脑核团进行观察结果。结果  13d龄组大鼠下丘脑核团各项体视学数据均大于 10d龄组 ,而与 16d龄组相比左别无显著性 ;13d龄组大鼠细胞密度高于 10d龄组 ,而 16d龄组比 13d龄组增高程度更为明显。结论 生后 13d左右的大鼠下丘脑显著发育阶段与大鼠行为改变有明显的变化  相似文献   
70.
BAG-1 is an anti-apoptotic protein that interacts with a variety of cellular molecules to inhibit apoptosis. It is also important in the prognosis of several human malignancies such as breast cancer. We have previously cloned the human BAG-1 promoter. Using BAG-1 promoter as a probe, we identi ed a cDNA clone that encodes a novel BAG-1 promoter-binding protein, termed FLJ20420. The FLJ20420 protein speci cally bind to BAG-1 promoter (-353 to -128 bp) and decreased BAG-1 promoter activity ~30% by cotransfect...  相似文献   
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