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81.
Bath application of
-fucose and
-fucosyllactose (
F1 increases the potentiation of the population spike amplitude (POP-spike) and the field excitatory postsynaptic potential (fEPSP) after tetanization of the Schaffer collaterals of the rat hippocampus. The ineffective isomers
-fucose and 3-fucosyllactose (3-F1) have no such effect. Since not only the maintenance of long-term potentiation LTP is influenced but also its induction is drastically improved, an effect of the sugars via the formation of glycoproteins but also via different actions on induction mechanisms is discussed. 相似文献
82.
French Donna L. Häglund Bert O. Himmelstein Kenneth J. Mauger John W. 《Pharmaceutical research》1995,12(10):1513-1520
Purpose. The objective of this study is to correlate drug release mechanism with measured drug concentration profiles in gel layers of Carbopol® matrices containing mesalamine or benzoic acid.
Methods. Release rate experiments with Carbopol® matrices were performed using a rotating disk apparatus. Matrices were frozen and the gel layer in the matrices was sliced using a microtome in a cryostat. Drug concentration profiles were determined by direct measurement of the concentration of the drug in the gel slices. The pH of the slices was measured using microelectrodes, and water content was measured by Karl Fisher titration.
Results. The concentration gradient in mesalamine matrices decreased over time and correlated with square root of time release rate kinetics. The concentration profiles of benzoic acid were unchanged over time and correlated with zero order release rate kinetics. Carbopol gel layers were highly hydrated (93–95% water). Gel layers in matrices with mesalamine had a more alkaline microenvironmental pH. This higher pH resulted in increased growth of the thickness of the gel layer and a reduction drug diffusivity in comparison to benzoic acid matrices.
Conclusions. The release rate kinetics of mesalamine and benzoic acid correlated to the measured concentration profiles. The shape of the concentration profiles is determined by the rate of growth of the Carbopol® gel layer and drug diffusivity. 相似文献
83.
Disc herniation in the lumbar spine during growth: Long-term results of operative treatment in 18 patients 总被引:1,自引:0,他引:1
M. Poussa D. Schlenzka S. Mäenpää J. Merikanto P. Kinnunen 《European spine journal》1997,6(6):390-392
We studied 18 patients who had undergone surgery for herniated lumbar discs between the ages of 11 and 17 years. The inclusion criteria for girls was an age of 15 years or below and for boys 17 or below at surgery. The mean follow-up time was 10 years and the clinical outcome was good. Age at surgery and length of the follow-up had no effect on the result. The radiological disc height at follow-up did not correlate with the follow-up time or age of the patient at operation. MRI scans at follow-up from ten patients operated at less than 15 years of age revealed multilevel disc degeneration but favourable clinical results. 相似文献
84.
Kazumasa Shindo MD Shin-ichi Tsunoda MD Zenji Shiozawa MD 《Clinical autonomic research》1994,4(6):299-302
Microneurography was performed in a 39-year-old woman with demyelination of the pontine white matter associated with muscle spasms in the lower extremities. Single bursts on the microneurogram were observed immediately after cessation of the spasm with no systemic changes in the blood pressure or heart rate. Voluntary tonic flexion of the lower extremities induced similar bursts with small amplitudes. These reflex bursts possessed a characteristic of muscle sympathetic nerve activity, because the latency between the peak of each burst and the prior R-wave on the electrocardiograph was constant. The occurrence of these bursts suggests that a segmental compensatory mechanism in the spinal cord may stabilize the muscle blood flow influenced by muscle contraction. 相似文献
85.
C.L. Richardson W.P. Tate S.E. Mason P.A. Lawlor M. Dragunow W.C. Abraham 《Brain research》1992,580(1-2):147-154
Expression of the immediate early gene zif/268 (also termed NGFI-A, Krox 24, TIS8 and Egr-1) was investigated in awake rats following various long-term potentiation (LTP) induction protocols.zif/268 mRNA (Northern blots) and protein (immunohistochemistry) levels sharply increased following LTP, and followed a time course characteristic of other immediate early genes. When measured across 3 tetanization protocols known to produce differing degrees of LTP persistence,zif/268 induction was found to be more highly correlated with LTP duration than with the magnitude of initial LTP. These data support the hypothesis that the immediate early gene zif/268 plays a role as a third messenger in the cascade of cellular and nuclear events that govern the persistence of LTP. 相似文献
86.
吴在东 《安徽卫生职业技术学院学报》2005,4(2):76-77,75
探索军工研究所发展民品产业之路.本文对军工研究所发展民品产业进行了优劣势分析,继而从机制转换,组织结构,产品战略,市场营销,人才队伍建设等方面提出了一些改革措施. 相似文献
87.
Laparoscopic colposuspension is one of many new operations for treating female urinary stress incontinence. With initially
reported success rates similar to those of the traditional open procedure, it appears to combine the advantages of laparoscopy
(such as minimal invasiveness and quicker return to normal activities) with the effectiveness of the standard procedure. Different
methods and approaches are used, but endoscopic suture techniques remain difficult and time-consuming. The use of endostapling
devices for fixation of alloplastic material has been a tempting alternative. We present a case during which laparoscopic
colposuspension was performed using staples and mesh. Incontinence did not improve, and the patient suffered severe chronic
pain for 18 months postoperatively. Removal of the alloplastic material and traditional abdominal resuspension led to complete
cure. 相似文献
88.
实施绩效考核的实践和体会 总被引:7,自引:0,他引:7
介绍绍兴市人民医院实施绩效考核的经验和体会.其经验在于:明确考核定位,把考核的首要目的定位于医院管理目标的实现和对管理过程的一种控制;运作方式是:制定考核标准、确立考核周期、明确考核部门及人员,使绩效考核真正落到了实处,收到了显著效果. 相似文献
89.
一氧化氮与胚胎异常发育的相关性研究 总被引:3,自引:0,他引:3
为了解开一氧化氮(NO)是否与畸胎发生有关这一谜团和进一步阐明砷致畸作用机理,本实验应用诱生型NO合成酶(iNOS)组织化学、扫描电镜(SEM)及体内致畸试验等方法研究了砷对小鼠卵黄囊胎盘(YSP)和胚胎发育的影响。结果表明YSP细胞iNOS表达与砷浓度之间存在明显的剂量—反应关系(P<0.05);SEM观察可见YSP内皮层和间皮层细胞受损;光镜下可见YSP变小、萎缩和微血管分化不良;随着染毒剂量的升高,畸胎率和死胎率亦逐步增加,最高分别达到56.8%和24.7%;畸胎的主要表现是神经管未闭,心包积液和体位异常等。研究结果率先提示过量NO与畸胎发生及致畸机理关系密切;推荐在致畸研究中iNOS可作为一种有效的生物标志物。 相似文献
90.
目的 研究电化学人工龋的电化学腐蚀机制。方法 采用循环伏安法研究牙片电极在K2SO4溶液中的氧化还原反应;以失重法并结合SPSS统计软件统计分析,评价牙片在KCl和K2SO4介质中恒电位腐蚀情况,并现场监测电解液氢离子浓度的变化情况。结果 在0.0-2.5V电位范围内,牙片电极与石墨电极具有波形类似的循环伏安曲线;在KCl和K2SO4介质中牙片的腐蚀速度无显著差异;2.0V恒电位腐蚀牙片8h后,阳极池本体溶液pH值由7.0平均下降到3.87,阴极池则由7.0平均升高到10.65。结论 在外电场作用下,牙片的阳极腐蚀与介质无关;水的阳极氧化引起阳极区氢离子浓度升高,致使牙齿发生酸溶是电化学人工龋形成的主要决定因素。 相似文献