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71.
72.
目的 观察在腕关节尺桡偏运动时,舟月骨间韧带(scapholunate interosseous ligament,SLIL)及其各亚区分级切断后对舟骨与月骨三维运动的影响,从亚区水平对SLIL在舟月骨三维运动中的作用进行研究.方法 取12例新鲜冰冻成人上肢标本(左、右侧各6例),共分为正常对照组、断SLIL近侧组、断SLIL近+背侧组、断SLIL近+掌侧组、SLIL全断组(每组6例).采用三维激光扫描及图像重建技术,测定在腕关节尺桡偏时舟骨与月骨的三维运动数据,并进行统计学处理.结果 在正常腕关节做尺桡偏运动时,舟、月骨同时也做尺桡偏运动,但还伴有明显的屈伸方向上的运动;与此同时,舟、月骨还做一定的旋前、旋后活动.在切断近+掌和近+背侧亚区组,舟月骨的活动受到影响.全切断SLIL会导致舟骨掌屈度增加,月骨掌屈活动减弱.结论 采用三维激光扫描及图像重建技术可准确测定腕舟月骨的三维活动度,从SLIL亚区水平上进行的研究表明,部分或全部切断SLIL后会对舟月骨的掌屈程度产生明显影响,但SLIL近侧亚区在控制舟、月骨的活动上不起主要作用.  相似文献   
73.
The evolution of the accommodative function and development of ocular movement are evaluated in a non-clinical paediatric population (1056 subjects) aged 6-12 years, providing means for each age in the optometric tests that evaluate the accommodative amplitude, accommodative facility, accommodative response (lag), and saccadic movements. A comparison of these values between ages (anova) established three distinct trends in the behaviour of these parameters. The accommodative amplitude, measured by modified dynamic retinoscopy, and the evaluation of the saccadic movements by the development of ocular movements [developmental eye movement (DEM)] test showed continuous change with age. The values for monocular and binocular accommodative facility, measured by +/-2.00 D flippers, indicated the need to divide the population into two age groups (6-7 and 8-12 years). Finally, the means of accommodative response, measured by monocular estimation model (MEM) retinoscopy, and the direct observation of saccadic movement revealed no significant differences between ages, establishing a single mean reference value for the age group studied.  相似文献   
74.
Psychogenic gait disorders can present in many different ways. Among patients with a pure psychogenic gait disorder, buckling of the knee is the most common feature, followed by astasia-abasia. Here, we describe one such patient with a very unusual gait disturbance that might be regarded as a variant of astasia-abasia. The patient characteristics are described and discussed in a historical context.  相似文献   
75.
76.
局部注射VEGF对大鼠正畸牙齿移动的影响   总被引:3,自引:1,他引:2  
目的:观察局部注射重组鼠的血管内皮生长因子(rrVEGF)对大鼠正畸牙齿移动的影响,探讨VEGF在正畸牙齿移动中的作用机制。方法:45只雄性SD大鼠,牵引其上颌第一磨牙近中移动,实验中分别将rrVEGF及生理盐水注射入实验组及对照组大鼠右侧上颌第一磨牙腭侧的骨粘膜下,于实验前3天开始注射,每3天一次。分别在加力l、3、7、14、2l天后记录上颌第一磨牙移动距离。然后将各组动物处死,用HE染色观察牙周组织变化情况并采用免疫组织化学方法对组织中表达的VEGF进行分析。结果:实验组大鼠压力侧破骨细胞教和成骨细胞数在实验全过程中均多于对照组,而且,实验组大鼠牙齿移动距离明显大于对照组。结论:进一步证实VEGF作为旁分泌因子,参与了牙齿移动过程中的牙周组织改建,内源性VEGF和注射VEGF都使牙齿移动量显著增加。因此,VEGF在正畸牙齿移动的机制中具有重要意义。  相似文献   
77.
Summary 15 normal volunteers were treated over three weeks with haloperidol (HAL) and in the third week additionally with biperidene (BIP). The order of the EEG spectra at different topographical locations and in different frequency bands during a movement task was analyzed using uncertainty analysis (UA), a multivariate analysis technique based on informationtheoretical methods. Different patterns of drug-induced changes were found. HAL decreases the theta and alpha band order at the fronto-central lateral areas but increases it at the fronto-central midline in the theta band and at the parietal areas in the alpha band. With the exception of the fronto-central midline locations, BIP more or less counterbalances the effect of HAL. Volunteers felt unwell and had motor disturbances during HAL and felt well again during HAL + BIP. Reaction time values were increased during HAL and normalized during HAL + BIP.  相似文献   
78.
The activity of single neurons in the superior colliculus was recorded while a rhesus monkey made arm movements to visual targets located on a screen in front of him. It was found that the activity of a subpopulation of cells was clearly related to these arm movements. The neurons began to discharge either with the onset of the movement, during the movement period, or well before the onset of electromyogram (EMG) activity and movement, and could be active for the entire duration of EMG activity. While the discharge pattern of some of these'reach'neurons was not different for movements to different target positions, other cells showed graded changes in activity depending on the direction of movement. The peak discharge rate could rise to > 100 impulses/s. Some units received somatosensory input; other reach cells exhibited a visual response and/or presaccadic activity. It is likely that the primate superior colliculus is not only involved in the initiation and control of orientating movements of the eyes but also in reaching movements of the arms.  相似文献   
79.
The Barthel Index (BI), the Modified Barthel Index (MBI) and the Functional Independence Measure (FIM) are all widely used by occupational therapists as assessment tools for clinical decision-making and outcome measurement. All of these tools have demonstrated validity and the BI and the FIM have demonstrated inter-rater reliability. The MBI has been modified to increase sensitivity; however, there have been no publications on the inter-rater reliability of this tool following the changes. The purpose of this research was to examine the inter-rater reliability of two versions of the Barthel Index, and draw some comparisons between this assessment tool and the FIM. Twenty-five patients with neurological and orthopaedic conditions were assessed by three occupational therapists using the three tools. The method of analysis selected was percentage agreement and intraclass correlation coefficient. The results indicated that both the original and modified versions of the Barthel Index possess good inter-rater reliability. As all three tools have demonstrated adequate reliability and validity, it is suggested that clinicians select the most sensitive tool that best meets their clinical needs, and use this assessment tool in its standardized format.  相似文献   
80.
损毁家兔单、双侧室旁核,观察迷走神经对皮层诱发的下颌运动抑制性影响的变化,发现损毁单侧室旁核不影响刺激迷走神经中枢端对皮层诱发的下颌运动的抑制作用;损毁双侧室旁核,迷走神经对皮层诱发的下颌运动的抑制作用消失。  相似文献   
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