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71.
Ken Hui 《Early child development and care》2006,176(3):411-419
In 1993, Rauscher et al. reported a temporary increase in spatial-temporal ability after listening to Mozart's music. This led to numerous replication and extension studies with mixed findings in the past decade. This study investigated the 'Mozart effect' in preschool children. Forty-one boys and girls, aged three to five, attempted a series of pencil-and-paper maze tests after each of three listening conditions: Mozart's Piano Concerto in A Major (K488), age-appropriate popular music and silence. Overall, there were no statistically significant differences among the three interventions. The results are discussed in relation to the findings of other investigations of the Mozart effect, and the need for further investigation of possible trends. 相似文献
72.
目的探讨重组腺病毒相关病毒(rAAV)-阳离子脂质体(LyoVec)复合载体的构建方法及其转染率评价。方法构建rAAv~GFP,rAAv—LyoVec复合载体及rAAV—GFP—LyoVec。倒置荧光显微镜观察,测定rAAV—GFP,LyoVec—GFP及rAAV—GFP-LyroVec对定量C6细胞的转染率,筛选出高转染率载体。结果rAAV—GFP组24、48、72和96h转染率分别为16%、23%、21%和9%;LyoVec-GFP组为28.5%、33%、32%和11%;rAAV—GFP—Lyovec组为49%、59%、64%和20%。rAAV-GFP—LyoVec纽分别在24、48、72和96h的转染率显著高于rAAV—GFP组(P〈0.01)及LyoVec—GFP组(P〈0.01)。结论新构建rAAV—LyoVec复合载体基因的转染效率远远高于rAAV或LyoVec独立转染。 相似文献
73.
74.
目的评价牙冠延长术在牙体缺损达龈下的残根残冠修复中的临床疗效。方法自2004年5月至2005年6月,对32例患者的36颗牙体缺损达龈下的患牙,术前按断端位于龈下最深距离分为A组(20颗患牙,距离<3.0mm)和B组(16颗患牙,3.0mm≤距离≤4.0mm),均采用牙冠延长术暴露龈下牙体断面,术后6周行桩冠修复。分别记录和比较手术前、后牙周探诊深度(PD)、菌斑指数(PLI)、龈沟出血指数(SBI)和牙齿松动度,以观察临床疗效。结果术后随访患者6个月,两组病例术后6周牙体断端均暴露较好、龈缘颜色正常,术后修复效果有效率为100%,满意率为77.78%。A组术后无松动,修复效果满意;B组术后50.00%出现Ⅰ度松动,修复效果欠佳,两组修复效果比较差异有显著意义(P<0.05)。术后各阶段两组的PD、PLI、SBI均明显优于术前(P<0.05),但两组术后牙周指数比较差异无显著意义(P>0.05)。结论牙冠延长术有利于残根残冠的保存和修复,但要注意适应证的选择。 相似文献
75.
Three-dimensional diffusion tensor tract (DTT) is the newest imaging to describe the structure of white matter fiber in three-dimensions, it has great significance in dividing the concrete anatomic site of gray and white matter lesions, displaying the correlation with fibrous band and judging clinical prognosis, which is incomparable by other imagings.OBJECTTVE: To observe the conditions of corticospinal tract (CST) in acute cerebral ischemic stroke patients,and analyze the relationship between motor function and the severity of CST injury.DESIGN: A case-control observation.SETTTNG: Department of Medical Imaging, Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA.PARTTCTPANTS: Fifteen patients with acute cerebral infarction were selected from Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA from February to December in 2005. They all suffered from acute attack and motor disorder of hemiplegic limbs to different extent, and were conformed by CT or MRI.There were 9 males and 6 females, aging 16-87 years old, the median age was 51.7 years, and all were right handed. Fifteen right-handed normal subjects, who were matched by age and sex with the patients in the cerebral infarction group, were selected from the relatives of patients and physicians of the Imaging Department as the control group. All the subjects were informed and agreed with the study.METHODS: The patients with acute cerebral infarction and subjects in the control group received MR diffusion tensor imaging (DTI) with GE 1.5 T nuclear magnetic resonance system, fiber tracking with the software of dTV- Ⅱ. Fractional anisotropy (FA) maps and three-dimensional tractography of bilateral CST of all patients were created. Displacement, continuity and destroy of fibrous bands were observed. At the same time, muscle strength of ipsilateral hand of patients with cerebral infarction was measured with Brunnstrom standard. The correlation between the severity of CST injury and the muscle strength of ipsilateral hand was analyzed with spearman correlation analysis.MAIN OUTCOME MEASURES: ① FA values in the infarcted sites and those in the contralateral corresponding sites of patients with cerebral infarction; ② CST manifestations in the patients with cerebral infarction and the control group.RESULTS: All the 30 testees were involved in the analysis of results. ① The FA values in infarcted sites of white matter were significantly lower than those in the contralateral ones (t =4.570, P < 0.001 ). ② In the control group, bilateral CST were reconstructed, they originated from precentral gyrus, went downwards to internal capsule, and extended to pontine and medulla oblongata, each fiber had good uniformity in continuous form. In the patients with cerebral infarction, the forms of contralateral CST were consistent with those in the control group with good continuity. Due to the involvement by the infarcted site to different extents, the ipsilateral CST manifested as continuous interruption and loss of uniformity in anatomic structure and form. The CST involvements were divided into three grades: integrated CST for grade I (n =2); integrated CST but compressed or displaced for grade 2 (n =5); interrupted CST for grade 3 (n =8). ③ The severity of CST injury was obviously correlated with the muscle strength of the ipsilateral hand (r=0.888, P< 0.05=.CONCLUSION: ① CST is injured to different extents in patients with acute cerebral infarction, and the severity of injury is associated with muscle strength. It is indicated that it can be used to judge the prognosis of rehabilitative treatment. ②DTT can directly display the status of pyramidal tract more three-dimensionally. 相似文献
76.
目的构建抑制黑色素瘤抗原-1(MAGE-1)的siRNA表达载体,鉴定其在人恶性胶质瘤细胞系SHG-44细胞中对MAGE-1基因表达的干涉作用。方法化学合成2对编码短发夹RNA序列的靶向MAGE-1基因寡核苷酸链,克隆到经BglⅡ、HindⅢ双酶切的pSUPER载体上,重组构建RNA干涉(RNAi)质粒载体。利用逆转录多聚酶链反应(RT-PCR)、流式细胞术和荧光显微镜,检测经稳定转染后SHG-44细胞中MAGE-1的表达,以了解siRNA的干扰效果。结果重组构建的pSUPER-MAGE-1载体经双酶切电泳及插入基因片段序列分析,表明寡核苷酸链成功插入到预计位点,并且序列与预期完全一致。稳定转染后G418筛选出的SHG-44多克隆细胞MAGE-1的表达经RT-PCR、流式细胞术和荧光显微镜检测,2对siRNA均有较明显的干涉作用。结论成功构建了针对MAGE-1基因的siRNA表达载体,抑制SHG-44细胞中的MAGE-1分子的表达。 相似文献
77.
78.
79.
目的:检测神经纤维瘤蛋白在先天性脊柱侧凸患者成骨细胞和软骨细胞中的表达。方法:6例先天性脊柱侧凸患者,在后路手术时取髂骨及髂骨生长板,分离、培养成骨细胞和软骨细胞,分别行碱性磷酸酶染色和甲苯胺蓝染色。逆转录-多聚酶链反应(RT—PCR)检测神经纤维瘤蛋白mRNA.间接免疫荧光和Westemblot检测神经纤维瘤蛋白在成骨细胞和软骨细胞中的表达。结果:先天性脊柱侧凸患者成骨细胞和软骨细胞中存在Ⅱ型神经纤维瘤蛋白表达,该蛋白主要分布在细胞浆,所表达蛋白为三磷酸鸟苷酶活化蛋白(GAP)活性较弱的Ⅱ型异构体。结论:先天性脊柱侧凸患者成骨细胞和软骨细胞中存在神经纤维瘤蛋白表达,但该蛋白是否通过对成骨细胞和软骨细胞的影响导致骨骼系统异常还有待于进一步研究。 相似文献
80.
计算机导航关节镜下前十字韧带重建术 总被引:1,自引:0,他引:1
目的介绍计算机导航技术辅助关节镜下前十字韧带重建术的术前规划和手术方法,比较导航技术辅助与单纯关节镜技术中股骨、胫骨隧道位置的优良率。方法根据术前标准正侧位X线片设计股骨、胫骨隧道的理想位置。术中“C”型臂X线机获得正侧位影像后输入计算机,形成虚拟工作界面。膝关节周围分别于股骨、胫骨侧安置“患者追踪器”。前十字韧带胫骨及股骨导向器上分别装配“工具追踪器”。经过注册及校准后,导航系统识别并捕获上述追踪器发射的信号,确定膝关节的位置,实时跟踪手术工具的位置和方向,并将隧道的虚拟路径叠加在工作界面上,供术者实时调整导向器的位置与方向,直至达到术前规划的要求。临床上完成计算机导航关节镜下前十字韧带重建术46例。对其中40例进行术后X线片测量,确定胫骨及股骨隧道的位置,并与同期进行的40例单纯关节镜下重建术隧道位置的测量结果进行比较。结果导航组胫骨隧道位置平均为45.35%±3.827%(37% ̄53%),股骨隧道位置平均为62.25%±5.610%(52% ̄73%);关节镜组胫骨隧道位置平均为41.05%±6.008%(25%~54%),股骨隧道位置平均为56.62%±7.316%(46% ̄77%)。导航组的股骨及胫骨隧道位置较关节镜组偏后,差异有统计学意义(P<0.05),导航组的标准差小于关节镜组。结论计算机导航技术可以使关节镜下前十字韧带重建手术中胫骨及股骨隧道的位置更偏后,提高了手术准确性及可重复性。 相似文献