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101.
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
102.
白花前胡丙素与类似物的化学沟通 总被引:1,自引:1,他引:0
目的:将白花前胡丙素与其类似物进行化学沟通,为进一步进行结构修饰奠定基础。方法:控制碱水解条件,得到白花前胡丙素的三个水解产物,采用在二氯甲烷溶剂中与相应的酸直接酰化的方法得到各种类似物。结果:合成了三种白花前胡有类似物,即3‘(S)-当归酰氧基-4‘(R)-异戊酰氧基-3‘,4‘-二氢邪蒿内酯、3‘(S),4‘(S)-二乙酰氧基-3‘,4‘-二氢邪蒿内酯和3‘(S),4‘(R)-二乙酰氧基-3‘,4‘-二氢邪蒿内酯。结论:合成的三个白花前胡丙素的类似物中,两个为新化合物,一个为已知的天然产物。 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.
目的:评价三种药物防治胃肠肿瘤化疗所致呕吐的价值。方法:90名患者随机分成三组,灭吐灵组(A组),吗丁啉组(B组),枢丹组(C组)。应用5-Fu+LV方案化疗5天,观察5天内三种药物的止吐效果。结果:A和B、C组比较有显著性差异(P〈0.05),B和C比较无显著性差异(P〉0.05)。结论:B组副作用少,疗效高,建议临床推广使用吗丁啉。 相似文献
108.
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
109.
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
110.
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