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71.
Summary In this experimental study, a neodymiumyttrium-aluminium-garnet (NdYAG) laser was used to induce highly reproducible focal spinal cord lesions in anaesthetized guinea pigs. The efficacy of high dose amino acid solution (HDAAS) on this injury is investigated. Experiments were performed on 36 animals divided into three groups; sham operated controls, laser irradiated surgical controls, and amino acid groups. Acute responses to injury were evaluated with somatosensory (SSEP) and motor evoked potentials (MEP) and functional recovery was assessed for 8 weeks using the inclined plane technique.In the laser irradiated surgical control group, MEP disappeared one hour after the laser injury, but SSEP revealed changes of amplitude and latency. In this group, the average value of the inclined plane at 24 hours after the laser application was 45.3±1.4 degrees. In the amino acid group, at the sixth hour of injury, MEP and SSEP changes improved with infusion of HDAAS for 4 hours. This improvement was statistically significant (for latency of SSEP U=140 p<0.05). Inclined plane value at 24 hours after the laser application was 65.5±1.2 degrees in this group.This study showed that application of NdYAG laser irradiation on the spinal cord induced spinal cord injury which presented as paraparesis, HDAAS may provide significant therapeutic protection in secondary damage following this injury and may have a potential role in the treatment of acute spinal cord injury. 相似文献
72.
采用体积排斥色谱法/ 示差折光指数/ 直角激光光散射/ 示差粘度三检测联用技术表征了氘化聚苯乙烯、聚苯乙烯和氘化聚苯乙烯- 聚异戊二烯。结果表明,在θ条件下,虽然氘化聚苯乙烯的化学依赖性常数υT,DPS比聚苯乙烯的化学依赖性常数υT,PS大,但25 ℃时在四氢呋喃中,氘化聚苯乙烯的分子尺寸仍小于聚苯乙烯的分子尺寸。由于嵌段共聚物的淋洗体积随组成变化,所以用传统的SEC/RI得不到准确的分子量。经比较膜渗透、小角激光光散射和基质辅助激光脱吸与离子化时间飞行质谱等的实验结果,证明体积排斥色谱法/ 示差折光指数/ 直角激光光散射/ 示差粘度三检测技术能准确地得到氘化二嵌段共聚物的分子量以及其它重要信息。 相似文献
73.
观察机械性损伤的海马神经细胞在不同浓度高晶体- 高胶体渗透压溶液中容积的变化。取原代培养大白鼠胚胎的海马神经细胞,用超声波机械损伤细胞后暴露于含0.5 g/L、1 g/L和2.5 g/L氯化钠的细胞培养基中15 m in。结果显示机械性损伤的细胞明显肿胀(P< 0.05)。当细胞暴露于不同浓度的高晶体- 高胶体溶液15 m in 后, 细胞容积与同一实验时间的对照值相比明显下降, 并保持至第7 d (P< 0.05)。表明受到机械性损伤的海马神经细胞在高晶体- 高胶体渗透压环境中的容积调节功能丧失或减弱。 相似文献
74.
Gangwar Sanjeev Jois Seetharama D. S. Siahaan Teruna J. Vander Velde David G. Stella Valentine J. Borchardt Ronald T. 《Pharmaceutical research》1996,13(11):1657-1662
Purpose. To determine the different conformations of the acyloxyalkoxy-linked cyclic prodrug 1 of the model hexapeptide 2 in solution and to investigate the relationship between these solution conformations and the cellular permeability characteristics of this prodrug.
Methods. Two-dimensional Homonuclear Hartmann-Hahn spectroscopy, Rotating-Frame Overhouser effect spectroscopy, circular dichroism and molecular dynamics simulations were used to find the solution conformers of cyclic prodrug 1.
Results. Our spectroscopic findings suggest that cyclic prodrug 1 exhibits a major and a minor conformer in solution. The major conformer appears to have a well-defined secondary structure, which involves a -turn and 4 1 intramolecular hydrogen bond, creating a compact structure with a reduced average hydrodynamic radius compared to the model hexapeptide 2.
Conclusions. The increased ability of cyclic prodrug 1 to permeate membranes compared to the model hexapeptide 2 could be due to reduction in the average hydrodynamic radius of the molecule facilitating paracellular flux and/or the reduction in the hydrogen bonding potential facilitating transcellular flux. 相似文献
75.
Shigeki Wakiyama Katsuhiko Yanaga Yuji Soejima Takashi Nishizaki Tomoharu Yoshizumi Keizo Sugimachi 《Transplant international》1996,9(4):359-363
We studied the significance of N-acetyl--glucosaminidase (-NAG) and type III procollagen peptide (P-III-P) in the effluent of rodent hepatic grafts. After total hepatectomy, the livers were preserved in chilled, lactated Ringer's solution and then divided into five groups (n=10 each): group 1, 4 h preservation only; group 2, 4 h preservation and rewarming; group 3, 6 h preservation only; group 4, 6 h preservation and rewarming; and group 5, minimal preservation only. The -NAG of groups 2 and 4 was significantly higher than that of groups 1 and 3 (0.98±0.5 U/l vs 0.21±0.12 U/l; P<0.01 and 1.76±0.67 U/l vs 0.38±0.25 U/l, respectively; P<0.01), while that of group 4 was significantly higher than that of group 2 (1.76±0.67 U/l vs 0.98±0.50 U/l; P<0.05). The P-III-P of group 4 was significantly higher than that of group 2 (0.133±0.008 U/ml vs 0.110±0.015 U/ml; P<0.01). We conclude that -NAG is a novel parameter of parenchymal and nonparenchymal cells, while P-III-P reflects the integrity of the hepatic sinusoidal extracellular matrix. 相似文献
76.
Naohiro Kajiwara Masahiko Taguchi Hiroshi Saito Shin Nakajima Aeru Hayashi Norihiko Kawate Chimori Konaka Hiromi Wada Harubumi Kato 《Transplant international》1996,9(3):194-200
We examined the efficacy of two new preservation solutions containing trehalose-an extracellular type (ET-K) of solution and an intracellular type (IT-K) of solution — in relation to that of Euro-Collins (EC) solution in 20-h canine lung preservation. Canine lungs were flushed with one of the three solutions (n=5 for each solution) after pretreatment with PGE1 (20 g/kg) and were stored for 20 h at 4°C. The left lungs were transplanted and evaluated to 6 h post transplant. In the ET-K group, the arterial oxygen tension after reperfusion was significantly higher than in the IT-K and EC groups. The pulmonary vascular resistance, wet/dry weight ratio, and histological evaluation of each transplanted lung in the ET-K group were also better than in the IT-K and EC groups. This indicates that ET-K solution is useful for 20-h preservation of canine lung grafts. 相似文献
77.
78.
RP-HPLC测定上感口服液中丹皮酚含量 总被引:2,自引:2,他引:2
应用RP -HPLC测定上感口服液中丹皮酚的含量。采用ODS色普柱 ( 2 5 0mm× 4 6mm ,5 μm) ,甲醇-水 -冰醋酸 ( 65∶35∶0 5 )为流动相 ,检测波长为 2 74nm。丹皮酚在 2 5~ 30 μg ml-1浓度范围内呈良好线性关系 (r =0 9999) ,平均回收率为 95 7%,RSD =2 1%(n =6)。方法准确、灵敏 ,回收率高。 相似文献
79.
高效液相色谱法测定岩舒注射液中苦参碱的含量 总被引:10,自引:0,他引:10
目的:建立岩舒注射液中苦参碱的反相高效液相色谱法。方法:采用C18柱,流动相为甲醇-水-氨水(195:60:2.25),检测波长为220nm。结果:苦参碱在0.052-1.04μg范围内线性关系良好(r=0.9985),日内和日间精密度RSD均小于2.0%,方法的平均回收率为99.5%。结论:本法简便、快捷,结果准确。 相似文献
80.
通天口服液治疗不同类型紧张型头痛的疗效比较 总被引:4,自引:0,他引:4
目的 :观察通天口服液治疗不同类型紧张型头痛的临床疗效。方法 :紧张型头痛病人 1 2 1例 ,分为发作性紧张型头痛组 44例和慢性紧张型头痛组 77例 ,口服通天口服液 1mo,治疗后 2mo内动态观察头痛程度、发作频率、持续时间的变化。结果 :治疗 1mo后 1 2 1例病人临床总有效率为90 .9% ,发作性紧张型头痛组临床有效率为 98% ,慢性紧张型头痛组为 87% (P <0 .0 1 )。停药 1mo后全组临床总有效率为 83 .5 % ,发作性紧张型头痛组临床有效率为 93 % ,慢性紧张型头痛组为 78%(P <0 .0 1 )。无效的 2 0例多为慢性紧张型头痛组病人。 2组病人未见不良反应发生。结论 :通天口服液治疗紧张型头痛安全、有效 ,对发作性紧张型头痛的疗效优于慢性紧张型头痛 相似文献