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21.
Dr W. Q. Ge Z. C. Luo J. Jin Y. C. Huang S. Wang S. J. Lui 《Medical & biological engineering & computing》1998,36(1):22-26
A novel cardiokymograph system is introduced. The new system features a capacitance transducer with increased sensitivity
and can be used in multichannel measurements. The novelty of this technique is the injection of a current into the patient
coupled with the use of a capacitive displacement transducer and the possibility of multichannel monitoring. It provides for
the possibility of removing breath noise when some signal processing technique, such as adaptive filtering, is used. Further
investigation is needed to demonstrate clinical significance and pathologies. 相似文献
22.
胎儿声振动刺激反应的研究 总被引:5,自引:0,他引:5
目的:了解不同孕龄胎儿对声振动刺激的反应。方法:对435例次正常中、晚期妊娠妇女进行声振胎心试验(VAS-T)、声振胎动试验(SPFM),并对声振动刺激前、后胎心率变化规律进行前瞻性研究。结果:(1)从24周开始,胎儿对声振刺激有反应,但大部分未能达到VAS-T诊断标准,而胎动反应良好。(2)妊娠28周开始,声振刺激后,90%以上的胎儿出现显著的胎动、胎心率加速反应,足月胎儿反应率在98%以上。(3)SPFM阳性率的显著提高早于VAS-T。提示:28周后胎儿神经系统发育已趋完善。胎儿运动神经的发育成熟早于植物神经。 相似文献
23.
When administered systemically, glucose attenuates deficits in memory produced by several classes of drugs, including cholinergic antagonists and opiate agonists. Glucose also enhances memory in aged rats, mice, and humans. In addition, glucose ameliorates age-related reductions in paradoxical sleep. Because deficits in paradoxical sleep are most marked in those individual aged rats that also have deficits in memory, treatments which improve one of these functions may similarly improve the other. The present experiments show that glucose attenuates deficits in paradoxical sleep and memory after atropine administration, with similar dose-response curves for both actions. In the first experiment, rats received saline, atropine (1 mg/kg), glucose (100 mg/kg) or combinations of atropine + glucose (10, 100, 250, and 500 mg/kg) 30 min before assessment on a spontaneous alternation task. In the second experiment, 3-h EEGs were assessed for spontaneous daytime sleep in rats administered saline, atropine (1 mg/kg), glucose (100 mg/kg) or combinations of atropine + glucose (10, 100 and 250 mg/kg). In both experiments, glucose significantly attenuated deficits at an optimal dose of 100 mg/kg. A third experiment assessed blood glucose levels after injections of atropine + glucose (100 mg/kg) and determined that blood glucose levels were similar to those produced by other treatments which enhance memory. These results are consistent with the view that paradoxical sleep and at least one test of memory are similarly influenced by atropine and glucose. 相似文献
24.
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
25.
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
26.
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
27.
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
28.
Introduction Suprasellar arachnoid cysts are uncommon developmental anomalies that are most often diagnosed in childhood. Because the natural history and pathogenesis of these remain poorly defined, optimal treatment guidelines are not yet established.Case report We report a case of spontaneous disappearance of a suprasellar arachnoid cyst that persisted after a ventriculoperitoneal shunt performed 10 years earlier. A 5-year-old boy presented with impaired visual acuity and urinary incontinence. Magnetic resonance (MR) imaging showed a large suprasellar cyst with noncommunicating hydrocephalus. A ventriculoperitoneal shunt was put in place to alleviate current aggravation of hydrocephalus symptoms. Because of the persistent size of the cyst and signs of brainstem compression on a repeat computed tomography (CT), we recommended surgical exploration and decompression. However, the boy’s parents declined any further surgical treatment, and the patient was subsequently lost to follow-up for 10 years. When the patient returned to our clinic at the age of 15 years, a repeat MR scan showed a complete disappearance of the cyst. His family denied any significant interval history.Discussion This case represents only the third reported case of spontaneous disappearance of a suprasellar arachnoid cyst. We discuss possible mechanisms and clinical characteristics of the disappearance of the arachnoid cyst with review of the literature. 相似文献
29.
目的探讨老年人自发性气胸的诊断及治疗,以提高老年人自发性气胸的诊治水平。方法回顾性分析我科1996年2月3日~2006年2月23日我科89例老年人自发性气胸的诊治经过。结果老年人自发性气胸的临床症状易被原发病掩盖,其临床特点有:(1)临床表现多不典型,症状以紫绀、气急多见,无明显胸痛;(2)以继发性气胸为多;(3)老年自发性气胸并发症、伴发病多;(4)肺复张时间长,负压吸引效果差;(5)交通型和张力型在老年自发性气胸当中较为多见;(6)易误诊;(7)由于基础疾病存在,肺功能差,发生气胸后易出现肺部感染、呼吸衰竭等并发症,死亡率高。结论老年人各器官储备功能差,肺功能差,同时多并存基础疾病,老年人自发性气胸后易出现肺部感染、呼吸衰竭等并发症,死亡率高,早期诊断和积极合理的治疗是降低老年人自发性气胸病死率的关键。 相似文献
30.
自然流产患者滋养细胞肝素表皮生长因子的表达及意义 总被引:11,自引:0,他引:11
目的 探讨自然流产患者滋养细胞肝素表皮生长因子 (HB EGF)的表达及其与滋养细胞增殖细胞核抗原 (PCNA)的关系。方法 选择自然流产患者和正常妊娠者各 2 0例 ,采用免疫组织化学法分析滋养细胞HB EGF和PCNA的表达。结果 HB EGF主要存在于细胞质 ,合体滋养层和细胞滋养层均有表达 ,部分流产滋养细胞不表达。自然流产患者滋养细胞HB EGF和PCNA的表达显著低于正常妊娠者 (P <0 .0 1) ,成正相关 (r =0 .4 5 4 ,P <0 .0 1)。结论 HB EGF的表达和滋养细胞增殖相关 ,HB EGF下降可能与自然流产的发生相关 相似文献