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21.
A. Larsson Ch. Jensen M. Bilting S. Ekholm H. Stephensen C. Wikkelsö 《Acta neurochirurgica》1992,117(1-2):15-22
Summary Thirteen patients with normal pressure hydrocephalus were operated upon with an externally manoeuvrable shunt system (Sophy SU8) in order to investigate its influence on clinical outcome, intracranial pressure and cranial CT parameters. The opening pressure was set at high at surgery and lowered stepwise at intervals of three months to medium and low. The clinical condition, intracranial pressure and cranial CT parameters were examined at the end of the 3 months interval on each pressure level.The patients improved within the first 3 months inspite of an unchanged mean intracranial pressure and remained in a stable clinical condition during the rest of the study period. The intracranial pressure was significantly reduced at 9 months. The ventricular index, Evans index, temporal horn and third ventricle width were reduced 3 months post-operatively and did not change significantly during the rest of the study. The pre-operative third ventricle width was correlated to high psychometric test results after shunt surgery. Reduction in ventricular index, Evans index and third ventricle width after surgery correlated to improvement in psychometric scoring.The clinical improvement after shunt surgery for normal pressure hydrocephalus is seen within 3 months and is independent of the adjusted valve pressure. 相似文献
22.
M Ochsner 《European journal of medicinal chemistry》1996,31(12):939-950
Zinc(II) phthalocyanine is the active component of the liposomal formulation CGP 55847 which showed a high activity in photodynamic therapy in a variety of animal tumours. The photophysical properties of zinc(II) phthalocyanine have been studied in detail and compared to those of Photofrin, the only sensitizing agent approved so far for phase III/IV clinical trials. Since the efficacy of photodynamic therapy intrinsically depends on the spectroscopic features of the sensitizer, quantum chemical methods have proven to be an efficient means for optimizing chemical structures. As will be shown, a simple modification of the time-honoured INDO model of Pople allows a prediction of the singlet and triplet state properties of molecules of the size of zinc(II) phthalocyanine with an rms error of ≤ 1000 cm−1. 相似文献
23.
用橡胶木粉填充线性低密度聚乙烯(LLDPE),研究了酸、碱溶液预处理木粉的效果和硅烷偶联荆(KH-570)、MMA接枝的天然橡胶胶乳(MGL-30)两种改性剂对橡胶木粉表面改性的效果,以及未粉粒径和填充量等对木粉/LLDPE复合材料力学性能的影响,并用SEM对复合材料拉伸断面的形态结构进行了分析。结果表明:木粉的拉径、木粉填充量和改性荆用量对复合材料的力学性能有较大的影响,经碱溶液预处理再用改性荆改性后的木粉能有效地改善木粉与LLDPE的界面粘结强度,提高橡胶木粉/LLDPE复合材料的力学性能。 相似文献
24.
Most clinicians agree that psychological factors are important considerations in the evaluation and treatment of headache patients. There has been a lack of systematic research, however, that has examined the relationship between these variables. Attention to such factors may become a greater concern as the frequency of a patient's headaches increases, there is increased disability secondary to headaches, and/or there is an inadequate response to usually effective treatment. In addition, there is no consensus as to the proper method to assess psychopathology in headache patients. 相似文献
25.
包裹胰岛微囊的物理性能研究 总被引:2,自引:0,他引:2
用3%海藻酸钠及2.2%CaCl_2所制备的微囊在高流速及高浓度的蔗糖溶液冲击下未见破裂,且微囊包裹活细胞经过二小时的剧烈搅拌,亦无损漏。改进法所制备的微囊具有良好的机械强度,其物理性能已达到临床进行包膜胰岛移植治疗糖尿病的要求。 相似文献
26.
海藻硫酸多糖的制备及其性质研究 总被引:11,自引:0,他引:11
目的 建立一套从褐藻中提取海藻硫酸多糖(SP)简单可行的工艺流程。方法 采用乙醇分级提取和Sevage去除蛋白的方法分离、纯化SP,并用Molish反应、Fehling反应、茚三酮法和硫酸基法等鉴定SP产品,用苯酚硫酸法测定SP产品中的糖含量,硫酸基法测定SP产品中的硫酸基含量。结果 从褐藻中得到了SP产品,其得率为3%,SP产品的总糖含量高达85.4%,硫酸基含量为5.3%。结论 我们建立的SP制备工艺流程简单可行,所得产品确系硫酸酯化的海藻多糖。 相似文献
27.
由聚酯二元醇、异佛尔酮二异氰酸酯和二羟甲基丙酸合成聚氨酯预聚体,以氨乙基氨丙基聚二甲基硅氧(AEAPS)为扩链剂,制备了AEAPS改性聚氨酯水分散液。与未改性的聚氨酯水分散液相比,AEAPS改性聚氨酯水分散液的粒径增大,但粒径分布和表面张力基本不变,说明疏水的聚二甲基硅氧烷侧链被包裹于分散颗粒的内部;此外,改性聚氨酯水分散液的冻融稳定性显著增强。AEAPS改性聚氨酯水分散液成膜后,吸水率明显下降,水在膜表面的接触角增加,400℃时热失重下降,具有良好的疏水性和耐热性。 相似文献
28.
Clinically, phenol is used often as a neurolytic agent to treat pain and spasticity. The purpose of this study was to examine the time course of denervation and recovery in several hindlimb muscles following application of a 5% aqueous solution of phenol to the sciatic nerve. Phenol was applied to the sciatic nerve of adult female rats either by intraneural or perineural injection. Axonal degeneration was evident within the sciatic nerve 2 days following phenol application, although variable amounts of damage were observed. By 2 weeks, the soleus and tibialis anterior had atrophied to 63% and 51% of control. Reinnervation of hindlimb muscles occurred between 2 and 4 weeks following the nerve block. Following denervation, the soleus became slower in that all of the fibers expressed the slow myosin heavy chain (MHC). At 5 months, maximum tension of the soleus was 74% of control and the muscle consisted of more fast fibers on average, some of which expressed IIx MHC. These data suggest that 5% phenol causes an injury to the nerve that is more severe than a crush injury, and that reinnervation of denervated muscles may be by motoneurons other than those that originally innervated the muscles. © 1996 John Wiley & Sons, Inc. 相似文献
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