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21.
Contradictory results have been reported about the inhibitory input to the medial rectus subdivision of the oculomotor nucleus of the cat. In the present ultrastructural study, we quantified the GABAergic and glycinergic terminals in the various subdivisions of the rabbit oculomotor nucleus with the use of post-embedding immunocytochemistry combined with retrograde tracing of horseradish peroxidase. The density of the GABAergic input to the medial rectus subdivision was as substantial as that to the other subdivisions and the postsynaptic distribution of the GABAergic and glycinergic innervation did not differ among the different oculomotor subdivisions. 相似文献
22.
Minzhong Yu Lezheng Wu Dezheng Wu 《Documenta ophthalmologica. Advances in ophthalmology》1990,76(1):37-46
The visual pursuit test is a method that collects and analyzes the characteristics of pursuit eye movements and examines the function of the eye movement system. This paper analyzes the model parameters of the smooth pursuit eye movement system in order to explore a method for improving the analysis. The input-output relationship of the smooth pursuit system can be expressed by a quasilinear model. We compute the model parameters (gain, phase, spectral purity, cross covariance) by digital signal processing. Eye movement is recorded by electrooculogram. Both eyes are tested individually. The visual target moves at frequencies of 0.2, 0.4, 0.8, 1.2, and 1.6 Hz. Ranges are gain, 1.01 to 0.70; phase, -0.1 ° to -66 °; spectral purity, 0.97 to 0.70; and cross covariance, 0.99 to 0.26. We tested 40 normal subjects as well as patients with ataxia (8), vertigo (18), and ophthalmoplegia (9). The oculomotor system of normal subjects functions as a linear system in the performance of this test at 0.2 to 0.8 Hz. The spectral purity dropped to about 0.70 at 1.6 Hz. The variability of all measures increases greatly at 1.6 Hz, which indicates that this target motion exceeds the tracking ability of many normal subjects and that the oculomotor system of normal subjects functions as a nonlinear system in this condition. Statistical tests show no significant differences between sex, age, and the two eyes. The model parameters tentatively proved effective in clinical application. 相似文献
23.
目的:研究紧咬、叩齿运动中松动牙牙合力的动态变化特征。方法:选择19例单侧下颌第一磨牙松动的患者,用PVDF动态牙合力仪测量健侧和患侧下颌第一磨牙节律性叩齿和紧咬运动中牙合力动态变化曲线,分析最大牙合力峰值和到达峰值的时间,对两侧的测量结果进行分析。结果:叩齿运动中健侧下颌第一磨牙牙合力峰值平均为25kg,到达峰值的时间为108ms;患侧的分别为21kg和126ms;紧咬运动中健侧下颌第一磨牙牙合力峰值平均为27kg,到达峰值的时间为768ms;患侧的分别为23kg和1023ms;经配对t检验,健侧与患侧的峰值及到达峰值的时间差异均有显著性。结论:牙齿松动导致咀嚼功能降低,牙合力值和牙合力上升的速度均降低。 相似文献
24.
胰、胆疾病患者血清GLS含量测定 总被引:3,自引:0,他引:3
目的 研究胰、胆疾病患者血清GLS含量及其临床意义。方法 测定胰、胆癌症与非癌患者GLS含量 ,然后分组统计分析。结果 胰癌组GLS(973± 32 2mg/L)显著高于胰脏非癌组 (5 75± 2 18)和糖尿病组 (5 37± 87) ;胆道癌组GLS(90 8± 2 73)显著高于胆道非癌组 (5 2 1± 10 9)。该五组GLS阳性率 (>6 6 0mg/L)依次为 93.8%、2 6 .7%、4 .1%、85 .7%、9.3% ;胰、胆癌症组均显著高于非癌疾病组。结论 胰、胆癌症患者血清GLS显著增加 ;测定GLS对癌症诊断具有显著临床意义 相似文献
25.
Tetsuo Kida Yoshiaki Nishihira Toshiaki Wasaka Yukie Sakajiri Toshiki Tazoe 《Clinical neurophysiology》2004,115(10):2223-2230
OBJECTIVE: We investigated modulation of the short- and long-latency somatosensory evoked potentials (SEPs) in a forewarned reaction time task. METHODS: A pair of warning (auditory) and imperative stimuli (somatosensory) was presented with a 2 s interstimulus interval. In movement condition, subjects responded by grip movement with the ipsilateral hand to the somatosensory stimulation when the imperative stimulus was presented. In counting condition, they silently counted the number of imperative stimuli. The SEPs in response to the imperative stimuli were recorded. RESULTS: Frontal N30 and central N60 amplitudes were significantly smaller in the movement than in the counting or rest conditions. None of the short-latency components differed between the counting and rest conditions. In contrast to the short-latency components, P80 was significantly larger in the counting than in the rest condition, and showed a further increase from the counting to the movement condition. The N140 amplitude was significantly larger in the movement than the rest condition, but was not changed between the counting and the rest conditions. CONCLUSIONS: The attenuation of the frontal N30 and central N60, and the enhancement of the P80 and possibly the N140 resulted from the centrifugal mechanism. The present findings may show the different effects of voluntary movement on the early and subsequent cortical processing of the relevant somatosensory information requiring a behavioral response. SIGNIFICANCE: The present study demonstrated the differential modulation of short- and long-latency components of SEPs in a forewarned reaction time task. 相似文献
26.
单纯下颌骨磨削法矫治下颌角肥大 总被引:7,自引:0,他引:7
目的 探讨下颌角肥大骨磨削法治疗的临床效果。方法 在局部肿胀麻醉下,采用口内切口入路,常规分离显露下颌骨,在预定需要矫正的下颌骨区域,使用特殊器械磨削下颌骨体外侧皮质骨、下颌骨下缘及下颌角骨质,同时对部分肥大的咬肌进行处理,矫治下颌角肥大。结果 对58例下颌角肥大患者均行下颌骨磨削法矫治,除1例术中损伤下齿槽血管引起出血外,无其他并发症发生。术后随访6~18个月,全部病例取得良好的矫治效果。结论 下颌骨磨削法矫治下颌角肥大是一种并发症少、安全有效的好方法。与截骨矫治下颌角肥大的方法相比,该术式保留了下颌骨的内板。维持了颌颈区的立体感。 相似文献
27.
三维重建单(双)靶点定向置管引流术治疗高血压壳核出血 总被引:1,自引:0,他引:1
目的回顾性分析三维重建单(双)靶点定向置管引流术治疗高血压壳核出血的疗效,验证该方法的有效性和可行性。方法将133例壳核脑出血病人的CT定位扫描资料输入计算机工作站,对血肿进行三维重建,根据血肿量的大小和形状设计1~2个靶点和引流管路径。应用立体定向技术将引流管(外径5mm,内径3mm)送至颅内预定靶点,术中应用10ml注射器轻柔抽吸血肿液化部分,术后将尿激酶(1~2万IU)注入血肿腔内,夹闭引流管2h后自然引流,每12h重复1次。复查CT证实剩余血肿量为最初的10%~15%时拔除引流管。结果平均置管1.5 d(1~3d),平均血肿排空率92.8%。术后1个月病死率6.0%,远期随访(平均22个月)病死率11.3%,优良率74.4%。结论该方法治疗高血压壳核脑出血,血肿排空较彻底,疗效可靠,尤其适用于血肿量较大(>25ml)且形态不规则的颅内血肿。 相似文献
28.
下颌骨髁状突骨折的CT诊断 总被引:12,自引:0,他引:12
通过对比下颌骨髁状突骨折患者的普通X线和CT检查结果,着重提出CT诊断下颌骨髁状突骨折的方法及重要意义。 相似文献
29.
H. Ono R. Akiyama Y. Sakamoto J. T. Pearson H. Tazawa 《Medical & biological engineering & computing》1997,35(4):431-435
As an avian embryo grows within a eggshell, the whole egg is moved by embryonic activity and also by the embryonic heartbeat.
A technical interest in detecting minute biological movements has prompted the development of techniques and systems to measure
the cardiogenic ballistic movement of the egg or ballistocardiogram. (BCG). In this context, there is interest in using an
electromagnetic induction coil (solenoid) as another simple sensor to measure the BCG and examining its possibility for BCG
measurement. A small permanent magnet is attached tightly to the surface of an incubated egg, and then the egg with the magnet
is placed in a solenoid. Preliminary model analysis is made to design a setup of the egg, magnet and solenoid coupling system.
Then, simultaneous measurement with a laser displacement measuring system, developed previously, is made for chicken eggs,
indicating that the solenoid detects the minute cardiogenic ballistic movements and that the BCG determined is a measure of
the velocity of egg movements. 相似文献
30.
观察18例32眼下蹲运动与高眼压的关系,分为下蹲120次,100次及80次三且,每组分别观察10眼、11眼及11眼,结果各组运动后眼压均见下降,平均为1.027±0.486kPa,1.355±0.770kPa及1.325±0.422kPa,运动前后有非常显著性差异,但各组之间差异不显著。同时观察3小时内眼压动态变化,下蹲120次组眼压下降维持时间最长,在运动后3小时与运动前眼压比较及与其余两组第3 相似文献