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71.
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   
72.
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   
73.
任重  石阳  谷贺 《中国医科大学学报》2000,29(3):184-185,188
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   
74.
鼻咽癌咽旁间隙受侵面颈联合野照射疗效观察   总被引:2,自引:0,他引:2  
目的:评价鼻咽癌咽旁间隙受侵受面颈联合野照射长期疗效。方法:从1991年1月至1993年12月,经CT诊断咽旁间隙侵犯,实行面颈联合野照射的鼻咽癌病人49例,按临床分期分层随机抽取同时期非面颈联合野射49例病人为对照组。5年局控率、生存率计算用Kaplan-Meier法,Log-rank作显著性检验。计数资料用χ^2检验。结果:面颈联合野组生存率、局控率曲线图明显高于非面颈联合野组(P〈0.05)  相似文献   
75.
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   
76.
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   
77.
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   
78.
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   
79.
谷子种子经高空气球搭载后的遗传变异研究   总被引:11,自引:2,他引:9  
目的 选育出高产、蛋白质和用脂肪含量高的谷子品(系)种。方法 利用高空气球搭载谷子的干种子,在高空飘游8h后回收种植,对其植物学特性及进行分析研究。结果 种子发芽率比对照低5.2%,发芽热比对照高21.1%。SP1代植株高度比对照低6.8cm,旗叶面积比对照高25%,穗重比对照高15.9%;SP3代大穗型株系性状相对稳定,其中SP3-2的种子蛋白质和脂肪含量均高于对照经高空气球搭载后的SPE-35  相似文献   
80.
Exposure of the body to microgravity during space flight causes a series of well-documented changes in Ca2+ metabolism, yet the cellular and molecular mechanisms leading to these changes are poorly understood. Calbindins, vitamin D-dependent Ca2+ binding proteins, are believed to have a significant role in maintaining cellular Ca2+ homeostasis. In this study, we used biochemical and immunocytochemical approaches to analyze the expression of calbinding-D28k and calbindin-D9k in kidneys, small intestine, and pancreas of rats flown for 9 d aboard the space shuttle. The effects of microgravity on calbindins in rats from space were compared with synchronous Animal Enclosure Module controls, modeled weightlessness animals (tail suspension), and their controls. Exposure to microgravity resulted in a significant and sustained decrease in calbindin-D28k content in the kidney and calbinding-D9k in the small intestine of flight animals, as measured by enzyme-linked immunosorbent assay (ELISA). Modeled weightlessness animals exhibited a similar decrease in calbindins by ELISA. Immunocytochemistry (ICC) in combination with quantitative computer image analysis was used to measurein situ the expression of calbindins in the kidney and the small intestine, and the expression of insulin in pancreas. There was a large decrease of immunoreactivity in renal distal tubular cell-associated calbindin-D28k and in intestinal absorptive cell-associated calbindin-D9k of space flight and modeled weightlessness animals compared with matched controls. No consistent difference in pancreatic insulin immunoreactivity between space flight, modeled weightlessness, and controls was observed. Regression analysis of results obtained by quantitative ICC and ELISA for space flight, modeled weightlessness animals, and their controls demonstrated a significant correlation. These findings after a short-term exposure to microgravity or modeled weightlessness suggest that a decreased expression of calbindins may contribute to the disorders of Ca2+ metabolism induced by space flight.  相似文献   
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