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71.
72.
自锁式防旋自动滑动加压钉板的研制与生物力学研究 总被引:1,自引:1,他引:0
目的研制自锁式防旋自动滑动加压钉板(self—locking type pro-rotary auto-sliding&compression nail plate,LPSC—NP)用于股骨颈骨折内固定,对其进行生物力学性能测试,为临床应用提供依据。方法采集18具新鲜成年股骨近端标本,制成股骨颈骨折,分别用LPSC—NP、3枚空心钉、双头中空加压螺纹钉、动力髋螺钉内固定,并进行生物力学测试,用SPSS统计软件对实验数据进行分析。结果LPSC—NP的承载能力和抗扭转强度、刚度均明显大于后三者。结论LPSC—NP固定股骨颈骨折牢固可靠,符合生物力学要求。该器械结构合理,简单适用,有一定的临床价值。 相似文献
73.
Purpose: The aim of the study was to provide information about the characteristics of three main types of orthokeratology (ortho‐k) lenses used in Hong Kong and to report on their performance based on the clinical impressions of a group of ortho‐k practitioners. Method: Twelve ortho‐k practitioners were interviewed between 1 March and 30 June 2001. Results: Most ortho‐k lenses were ordered from three manufacturers: DreimLens, Fargo and Contex. The median maximum myopia reduction reported for DreimLens, Contex and Fargo lenses were 6.25 D, 6.00 D and 4.50 D respectively. The time to reduce myopia by up to 4.00 D could be up to three weeks for Contex and DreimLens and up to four weeks for Fargo. For reduction of myopia by up to 4.00 D, the treatment usually required only one or two lenses per eye for all three types of lenses. The incidence of lens binding and lens tightening after achieving the optimal reduction was reported to be higher with the DreimLens design. Good centration, less lens binding, relatively lower incidence of complications and lens tightening after achieving the optimal reduction were reported with the Fargo lenses. Conclusions: DreimLens tended to be more effective for myopia reduction. However, some practitioners were concerned with the aggressiveness of myopia reduction using this lens design and the higher potential for ocular complications. Selection of the lens design is dependent on various factors, in particular, practitioners need to be comfortable with the design they choose and to consider the needs of their patients and the final goal of the treatment. 相似文献
74.
Poststroke DNA immunization against neurite growth inhibitors is beneficial to the recovery from local cerebral ischemia in rats 总被引:1,自引:1,他引:0
Xingbao Zhu Jasmine Lee Jill Wong Wan Loo Tan Zhongtang Feng Tinghua Wang Zhicheng Xiao Ivan Ng 《中国神经再生研究》2007,2(2):65-69
BACKGROUND: Inhibitory signals, i.e. neurite growth inhibitors (NGIs), presenting on central nervous system (CNS) myelin have been shown to play a crucial role in inhibiting lesioned axonal sprouting and leading to less functional recovery. Vaccines targeting NGIs may provide multifactorial protection against brain insults by overcoming the inhibitory effects of these NGIs and boosting the body's immune repair mechanisms.
OBJECTIVE: To evaluate the effect of poststroke DNA immunization against NGIs on the rehabilitation for sensorimotor function of rat models of local cerebral ischemia.
DESIGN: Completely randomized grouping design, and controlled experiment.
SETTING: Brain Injury Research Laboratory, Department of Neurosurgery, National Neuroscience Institute, Singapore. MATERIALS: Sixty adult male Sprague-Dawley rats ranging in age from 45 to 120 days and in weight from 180 to 250 grams were provided by Animal Center of Department of Anatomy, Faculty of Medicine, National University of Singapore. pcDNA3.1(+)-neurite growth inhibitors (pcDNA-NGIs) a gift was provided by Dr. Xiao from Department of Clinical Research, Singapore General Hospital, Singapore. METHODS: The experiment was carried out at Brain Injury Research Laboratory, Department of Neurosurgery, National Neuroscience Institute, Singapore from August 2003 to April 2005. (1)The involved rats were randomized into 3 groups: pcDNA-NGIs group (group A), pcDNA3.1 (+) group (group B) and model group (group C), with 20 rats in each group. Left focal cerebral ischemia (FCI) was permanently induced through middle cerebral artery occlusion (MCAO) with the assistance of an operating microscope. Successful MCAO was determined by a 20% decrease to baseline in the ipsilateral cerebral blood flow. 100 μg of pcDNA-NGIs eluted in phosphate-buffered saline (PBS) was intramuscularly injected into the tibial muscle once a week after MCAO for 6 weeks in group A. As control, pcDNA3.1 (+) was also administrated in the same way in group B and nothing was administrated in group C. (2) The modified neurological severity score (mNSS), a composite of motor, sensory, reflex and balance tests, was used to test the sensorimotor deficit. The mNSS was graded on a scale of 0 - 18, i.e. normal score was 0, maximal deficit score was 18, and 1 point was warded for the inability to perform the tasks or the lack of a tested reflex. (3) The newly generated axons of corticorubral projection were traced by stereotaxic guided injection of 100 g/L biotinylated dextran amine. Rats were sacrificed two weeks after tracing, and cryostat coronal sections of midbrains (30μm) were reacted to BDA according to the manufacturer's instruction by the free-floating method. Images were captured on a DM RXA2 LEICA Microscope with a Spot Digital Camera system (Germany), and the numbers of labeled axons on the denervated side in four standard coronal sections including the red nucleus were manually quantified.
MAIN OUTCOME MEASURES: (1) The number of newly generated axons of corticorubral projection. (2)The improvement in sensorimotor deficit.
RESULTS: All the involved 60 rats entered the stage of final analysis. (1) The number of newly generated axons of corticorubral projection of rats: Only ipsilateral axons of CRP were noted with little evidence of fibers crossing to the contralateral red nucleus in rats of groups B and C. More BDA-positive fibers crossing the midline and terminating in the contralateral red nucleus in appropriate target areas mirroring the non-differentiated red nucleus were found in rats of group A. Quantitative analysis showed that BDA-labeled axons in the denervated side of rats in group A were more than those in group B (P 〈 0.05). (2) Improvement in sensorimotor deficit of rats: At 2 weeks after immunization, significant improvement in sensorimotor deficit was found in rats of group A. There were significant differences of improvement in sensorimotor deficit of rats between group A and group B or group C at 12 and 14 weeks after immunization (P 〈 0.05).
CONCLUSION: (1) Poststroke DNA immunization against NGIs leads to increased sensorimotor recovery following FCI and compensatory newly growth of axons from corticorubral projection. 相似文献
75.
探讨人的增强子结合蛋白(C/EBP)相关基因。方法以大鼠C/EBPcDNA为探针,筛选人胎盘cDNA文库。结果得到一个含有1975碱基命名为HP8的cDNA克隆,其中1~604位碱基属编码区。经基因数据库查对未发现同源基因。该基因编码的蛋白C-末端含有亮氨酸拉链结构(leucine zipper struceure)和C/EBP功能区(C-末端60个氨基酸)同源性高达97%,而上游编码区则与C/EBP及其已知家族同源性很低,表明该基因属C/EBP基因家族新成员。基因组Southern杂交证实该基因为单拷贝基因。在14种胎儿组织中显示小肠、皮肤高表达,肾上腺中度表达,肝、肺、肾、甲状腺、胆囊低表达。在3例正常成人肝组织中仅1例低表达,而在5对肝癌及癌旁肝组织中显示2例癌组织及1例癌旁组织高表达。结论以上结果提示该基因可能与细胞增殖有关。 相似文献
76.
77.
面肌痉挛显微血管减压术的诱发肌电图监测和评估 总被引:1,自引:0,他引:1
目的:探讨面神经诱发肌电图在显微血管减压(MVD)术中、术后对面肌痉挛治疗效果的监测和评估。方法:对26例典型面肌痉挛病人、探讨在MVD术前、术中、术后,经皮刺激痉挛侧(手术侧)面神经下颌缘支,记录诱发同侧眼轮匝肌肌电位(MD-OC反应)变化,并以正常侧作对照检查。结果:26例术前均记录到痉挛侧MD-OC反应,在术中操作不同阶段,21例均见MD-OC反应消失。术后1周~3个月随访复查21例中,12例痉挛完全消失,MD-OC反应不复存在,9例症状明显或部分减轻,但有4例再记录到MD-OC反应。另5例术中,术后均记录到MD-OC反应,症状未有改善。结论:面神经诱发肌电图运用于MVD术中监测和预后判断,可改善和提高面肌痉挛的治愈率。 相似文献
78.
79.
正常国人肺静脉血流多普勒频谱分析 总被引:23,自引:2,他引:21
运用彩色多普勒超声观察了107例正常国人的肺静脉血流(PVF)。结果:正负四相型(SIS2DA),占37%;正负三相型(SDA)占45%,正向两相型(SD)占18%。呼吸,性别不显著影响其表现,但心率、心律及取样容积位置均影响之。94%(101/107)正常者的SF>50%,表明正常国人前向性PVF主要是收缩期占主型,增龄使这一特征更明显。98%(105/107)正常者PVF的Ap<40cm/s,且其不受年龄影响。结论:正常国人PVF超声表现的多形性间有本质上的同一性,正确认识之有助于指导辨别病理性PVF频谱 相似文献
80.
云南省卫生资源配置标准的弹性系数研究 总被引:2,自引:1,他引:1
目的 在进行云南省区域分类基础上制定云南省区域卫生资源配置标准标志值后 ,根据云南省各个地区的特点增加不同弹性系数。方法 采用流行病学研究方法 ,收集和分析云南省不同地州市 1990~ 1999年有关人口、社会经济状况及卫生经费的投入、居民健康状况、居民文化、生活水平、少数民族状况、旅游地区、边境线长短及贫困状况等资料。结果 研究结果表明曲靖地区、玉溪市、保山地区增加弹性系数最少 ,分别为 0 67%、 1 5 8%和1 68% ,怒江州、迪庆州和西双版纳州增加弹性系数最多 ,分别为 11 15 %、 10 2 5 %和 9 84 %。其它地区的弹性系数分别为昆明市 5 88% ,昭通地区 2 3 1% ,楚雄州 2 3 0 % ,红河州 7 0 3 % ,文山州 5 5 3 % ,思茅地区 7 4 3 % ,大理州4 94 % ,德宏州 6 78% ,丽江地区 4 3 5 % ,临沧地区 6 13 %。结论 云南省区域卫生配置标准的弹性系数研究为云南省卫生资源区域分类配置标准提供了科学依据 ,不同弹性系数体现了云南省不同地区的卫生资源区域分类配置标准的公平性、合理性及实用性 相似文献