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101.
Gulyakov MB 《Neuroscience and behavioral physiology》2004,34(3):259-264
Studies were performed on five dogs. Chronic experimental conditions were used to study the responses of individual neurons in the caudate nucleus to the spatial characteristics of an acoustic signal. The results showed that 92% of sound stimulus-responsive neurons in the head of the caudate nucleus in dogs generated asymmetrical responses to contra- and ipsilateral monaural stimulation, with contralateral stimulation being more effective. In 50% of caudate nucleus neurons, simultaneous stimulation of both sound inputs was more effective than contralateral stimulation. A total of 77% of sound-responsive caudate neurons demonstrated sensitivity to changes in the magnitude and sign of the interaural delay. 相似文献
102.
目的:探讨连续硬膜外阻滞治疗腰椎间盘突出的适应证和疗效相关因素。方法:经腰(骶)部穿刺,1%利多卡因连续硬膜外腔阻滞法。结果:随访151例,随访8~31个月,优良83例(55.0%),疼痛明显改善,以中央型和腰痛为主的椎间盘突出较为有效。结论:本封闭法疗效与椎问盘突出部位、类型有关,可适用于疼痛严重的椎间盘突出。 相似文献
103.
先秦社会时空方位观对中医理论的影响 总被引:1,自引:0,他引:1
先秦社会的五行阴阳以及四风系统的时空方位观对中医理论发展有着很大影响 ,说明中医理论是在接受先秦时期科学技术思想及社会观念发展起来的 ,有许多内容尚待探讨 ,如仅用秦汉后的观点去认识是会有偏误的。 相似文献
104.
目的:探讨面神经麻痹面肌运动点的兴奋性与运动科板次级突触间隙的关系方法岙神经麻痹模型,应用盐酸消化法制作口轮匝肌招揽世镜标本者观察。结果:压10s组镒级突触间隙隙沟数量比对照侧减少而变浅。压榨30s组次级突触间隙隙沟明显减少平坦。结论:运动点失神经支配程度表明次级突触间隙病变程度,也表明面神经受损伤程度。 相似文献
105.
106.
在 32具成人尸体 (男、女各半 )正中矢状断面上 ,选取脊柱C2 -T1段进行观测 ,取相邻椎骨的前缘、中份、后缘测量它们之间的距离 ,以及解剖左、右侧椎间孔 ,测量椎间孔的最大垂直高度及最大宽度。结果 :椎体间间隙的高度、前缘为 3 48~ 5 .38mm ,中份为 4 84~ 7 14mm ,后缘为 3 0 5~ 3 84mm ;椎间孔的高度为 7 0 0~ 8 10mm ,宽度为 5 0 0~ 7 35mm。以上对颈椎间隙的定量研究为颈椎病变的影像诊断和临床手术提供解剖学依据。 相似文献
107.
A. C. M. Schrikker H. Wesenhagen S. C. M. Luijendijk 《Pflügers Archiv : European journal of physiology》1995,430(5):862-870
In this study we have investigated the effects of breath holding and of the physical properties of gases on four different respiratory dead spaces (V
D): the Fowler, the physiological, the washout and the inert gas dead space. The experiments were performed with dogs which were ventilated artifically with breathing patterns with different post-inspiratory breath holding times (t
a) of 0, 0.5, 1.0 and 2.0 s. Tracer amounts of acetone, ether and enflurane were infused continuously into a peripheral vein and a bolus of a mixture of krypton, Freon12 and SF6 was introduced into the peritoneal cavity. After reaching steady state, samples of arterial blood, mixed venous blood and mixed expired air were taken simultaneously. From the partial pressures (P
a, P
¯V and P
respectively) we determined the excretion (=P/P¯V), retention (R=Pa/P¯V) and the physiological dead space fraction (V
D,phys/V
T=(1 P/Pa) for each gas, where V
T is tidal volume. Further, we recorded the expirograms of the six tracer gases and of CO2 from which the Fowler dead space fractions (V
D,Fowler/V
T) of the different gases were determined. Also the washout dead space fractions (V
D,washout/V
T) for He and SF6 were determined as well as the inert gas dead space fraction (V
D,MIGET/V
T) with the use of the multiple inert gas elimination technique (MIGET).With the exception of V
D,phys/V
T for SF6, all dead space fractions decreased with increasing t
a. V
D,phys/V
T for the poorly soluble gas SF6 was considerably larger than V
D,phys/V
T for the remaining gases. For the highly soluble acetone V
Fowler/V
T was considerably smaller than V
D,Fowler/V
T for the other gases. V
D,washout,SF6/V
T was always larger than V
D,washout,He/V
T and V
D,Fowler,SF6/V
T. Further, V
D,phys/V
T was larger than V
D,Fowler/V
T for SF6 and acetone. However, for gases with intermediate solubility in blood V
D,phys/V
T tended to be smaller than V
D,Fowler/V
T. We conclude that the respiratory dead spaces are affected by the breathing pattern and by the physical properties of gases, i.e. their diffusivity in alveolar gas and their solubility in blood or lung tissue. 相似文献
108.
G. Nakos A. Lachana A. Prekates J. Pneumatikos M. Guillaume K. Pappas H. Tsagaris 《Intensive care medicine》1995,21(11):904-912
Objective To evaluate the effect of tracheal gas insufflation (TGI) in spontaneously breathing, intubated patients with chronic obstructive pulmonary disease (COPD) undergoing weaning from the mechanical ventilation.Design A prospective study in humans.Setting Polyvalent intensive care unit (14-bed ICU) in a 700-bed general university hospital.Patients Twelve patients with chronic obstructive pulmonary disease (COPD) who required intubation and mechanical ventilation were studied. All patients met standard criteria for weaning from mechanical ventilation. Seven patients (group 1) had been transorally intubated during episodes of acute respiratory failure. Five patients, all men (group 2), had previously undergone tracheostomy and had a transtracheal tube in place.Interventions Intratracheal, humidified, O2-mixture insufflation (TGI) was given via a catheter placed in distal or proximal position. Gas delivered through the intratracheal catheter was blended to match the fractional of inspired gas through the endotracheal tube. Continuous flows of 3 and 6 l/min in randomized order were used in each catheter position. Prior to data collection at each stage, an equilibration period of at least 30 min was observed, and thereafter blood gases were analyzed every 5 min. A new steady state was assumed to have been established when values of bothP
aCO2 and
CO2 changed by less than 5% between adjacent measurements. The last values of blood gases were taken as representative. The new steady state was confirmed within 35–50 min. Baseline measurements with zero
were made at the beginning and end of the experiment.Results This study shows that VT, MV,P
aCO2, and VD/VT are reduced in a flow-dependent manner when gas is delivered through an oral-tracheal tube (group 1). The distal catheter position was more effective than the proximal one. In contrast, when gas was delivered through tracheostomy (group 2), TGI was ineffective in the proximal position and less effective than in group 1 in distal position.Conclusion Under the experimental conditions, tracheal gas insufflation decreased dead space, increased alveolar ventilation and possibly reduced work of breathing. From the preliminary data reported here, we believe that TGI may help patients experiencing difficulty during weaning. 相似文献
109.
Identification of the central vestibular projections in man: a positron emission tomography activation study 总被引:4,自引:0,他引:4
Gabriella Bottini Roberto Sterzi Eraldo Paulesu Giuseppe Vallar Stefano F. Cappa Francesco Erminio Richard E. Passingham Chris D. Frith Richard S. J. Frackowiak 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1994,99(1):164-169
The cerebral representation of space depends on the integration of many different sensory inputs. The vestibular system provides one such input and its dysfunction can cause profound spatial disorientation. Using positron emission tomography (PET), we measured regional cerebral perfusion with various vestibular stimulations to map central vestibular projections and to investigate the cerebral basis of spatial disorientation. We showed that the temporoparietal cortex, the insula, the putamen, and the anterior cingulate cortex are the cerebral projections of the vestibular system in man and that the spatial disorientation caused by unilateral vestibular stimulation is associated with their asymmetric activation. 相似文献
110.
目的:观察斜外侧椎间融合(oblique lateral interbody fusion,OLIF)治疗腰椎病变术后融合器沉降现象,总结融合器沉降特点,并分析其原因,提出预防性措施。方法:回顾性分析2015年10月至2018年12月收治的144例腰椎病变资料,其中男43例,女101例;年龄20~81(60.90±10.06)岁;腰椎间盘退行性病变17例,巨大型腰椎间盘突出12例,椎间盘源性腰痛5例,腰椎管狭窄症33例,腰椎退行性滑脱26例,腰椎椎弓峡部裂伴椎体滑脱28例,腰椎内固定术后邻椎病11例,炎症转归期原发性椎间隙炎7例,腰椎退行性侧后凸5例。术前双能X线骨密度检查提示存在骨量减少或骨质疏松57例,骨密度正常87例。融合节段数:单节段124例,2节段11例,3节段8例,4节段1例。采用Stand-alone OLIF 40例,OLIF联合后路椎弓根螺钉固定104例。记录术后融合器沉降的发生情况,对可能风险因素进行单因素分析,观察融合器沉降对于临床结果的影响。结果:所有手术顺利完成,手术时间中位数99 min,术中出血量中位数106 ml;术中发生终板损伤30例,合并椎体骨折5例。所有患者获得随访,时间6~30(14.57±7.14)个月。随访过程中除原发性腰椎间隙炎病例、部分腰椎椎弓峡部裂伴椎体滑脱病例,其余出现不同程度的融合器沉降现象,其中正常沉降119例,异常沉降25例(Ⅰ级23例,Ⅱ级2例)。未出现椎弓根螺钉系统松动或断裂现象,椎间隙高度由术前的(9.48±1.84) mm恢复至术后3~5 d的(12.65±2.03) mm及末次随访时的 (10.51±1.81) mm,术后3~5 d与术前比较、末次随访与术后3~5 d比较差异均有统计学意义(P<0.05)。椎间融合率为94.4%(136/144)。腰痛和腿痛视觉模拟评分(visual analogue scale,VAS)分别由术前的(6.55±2.29)、(4.72±1.49)分降低至末次随访时的(1.40±0.82)、(0.60±0.03)分(P<0.000 1);ODI由术前的(38.50±6.98)%恢复至末次随访时的(11.30±3.27)%(P<0.05)。并发症发生率为31.3%(45/144),再手术率9.72%(14/144),其中因融合器沉降或移位而再次手术8例,占再手术的57.14%(8/14)。单因素分析结果显示:在骨量减少或骨质疏松组、Stand-alone OLIF组、2节段或以上融合组、终板损伤组中其异常沉降例数分别高于骨量正常组、OLIF联合椎弓根螺钉固定组、单节段融合组、终板无损伤组。结论:融合器沉降是OLIF术后较为常见的现象,术前骨量减少或骨质疏松、Stand-alone OLIF应用、2节段或以上融合和术中终板损伤可能是术后融合器沉降的重要因素。虽然融合器沉降程度与临床症状无明显相关,但存在融合器移位的风险,需要加强预防,以降低因融合器沉降而带来的严重并发症,包括再手术。 相似文献