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71.
R GOKAL 《Nephrology (Carlton, Vic.)》1996,2(S1):s159-s162
Summary: Current peritoneal dialysis solutions are not biocompatible, particularly in respect to low pH, high osmolality and use of lactate. In addition, glucose is not an ideal osmotic agent. Recent advances in the formulation of peritoneal dialysis fluids aim to provide a more physiological environment to preserve membrane integrity. the effects of pH and lactate have been overcome by the use of bicarbonate based solutions whilst icodextrin (glucose polymers) often prolonged ultrafiltration in spite of being isomotic to uraemic plasma. Future formulations will see a combination of osmotic agents (including amino acids) and bicarbonate to achieve a more biocompatible solution whilst still meeting the ultrafiltration needs of the patients. Additives (glycosaminoglycans, procysteine) may protect the peritoneum from free radical injury. 相似文献
72.
人工牛黄中胆酸和总胆酸含量测定方法探索 总被引:2,自引:0,他引:2
李隆康 《中国生化药物杂志》1996,17(1):22-24
根据胆酸和猪去氧胆酸与硫酸加效产生脱水反应,形成共轭双键,在不同条件下各自在紫外区产生相同特征吸收峰,试采用紫外分光光度法对照品比较法进行人工牛黄中胆酸和总胆酸的含量测定。经实验证明方法可行,较现行卫生部标准法简单、准确、重现性好,易于普及推广。 相似文献
73.
1-乙基-6-氟-1,4-二氢-4-氧代-7-(4-芳酰硫代氨甲酰基-1-哌嗪基)-3-喹啉羧酸的合成及抗菌作用 总被引:4,自引:1,他引:3
Thirteen new 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(4-aroyl-thiocarbamoyl- 1 piperazinyl)-3-quinoline carboxylic acids were prepared, Their structures were characterized by elemental analysis, IR, HNMR and MS spectra.Preliminary pharmacological tests indicated that some of compounds Ia~m possess strong inhibiting activity against Escherichia coli, Bacillus subtilis and Proteus at concentration of 100 μg/ml. 相似文献
74.
Introduction – Toxic phytanic acid concentrations in patients with Refsum's disease can be reduced by plasma separation, performed either as plasmapheresis, or as cascade filtration. The latter procedure is as efficient and safe as plasmapheresis, and eliminates the need for albumin replacement. This study investigates the loss of immunoglobulins associated with the procedure. Material and methods — Immunoglobulin- and phytanic acid serum concentrations before and after cascade filtration (n=16) were measured in a patient with Refsum's disease and their removal determined. Filters with sieving coefficients for immunoglobulin G of 70% and 30% were compared with each other and with historical data on plasmapheresis. Results — While differences in immunoglobulin M loss are negligible, the loss of immunoglobulin G in cascade filtration is significantly less than that reported for plasmapheresis and depends upon the pore size of the employed filters. The loss is least with larger pore size, but this advantage becomes statistically insignificant if immunoglobulin G loss is related to the lesser decrease in phytanic acid concentration that was achieved simultaneously in this study. Conclusion — Unless transplantation of a-hydroxylase containing tissue can be established as treatment for Refsum's disease, cascade filtration appears to be the treatment of choice in order to avoid loss of albumin and to reduce the loss of immunoglobulin G. 相似文献
75.
76.
目的:为设计维甲酸治疗神经母细胞瘤可能的有效方案,本文对9-顺式维甲酸(9-cis retinoic acid,9-cisRA)体外诱导分化神经母细胞瘤细胞(SK-N-SH)作用进行了研究。方法:SK-N-SH细胞经9-cisRA处理后,采用相差显微镜,神经纤维银染法,透射电镜观察等手段。观察9-cisRA对细胞生长的影响。结果:9-cisRA作用SK-N-SH细胞7d后,细胞形态发生变化;12d时出现神经原性表型,多个细胞形成“神经节”,节间形成粗而长的类神经纤维;尼氏小体和银染法亦证明细胞产生显著分化,透射电镜观察结果表明,9-cisRA对该细胞有分化作用。却无明显凋亡诱导作用。结论:9-cisRA对神经母细胞瘤细胞体外能产生明显诱导分化作用。 相似文献
77.
Release of cholecystokinin from rat cerebral cortex in vivo: role of GABA and glutamate receptor systems 总被引:1,自引:0,他引:1
Using cortical cups in chloralose-urethanized rats, the in vivo release of cholecystokinin-like immunoreactivity (CCK-LI) from cerebral cortex was examined. Resting levels of cholecystokinin-like immunoreactivity ranged from 20 to 30 pg/20 min sample. The addition of potassium (40 mM) in excess, resulted in a highly significant elevation in the levels of CCK-LI in the cortical superfusate. Deletion of calcium and the substitution of cobalt (10 mM), resulted in a significant reduction in both resting release and the release otherwise evoked by the addition of potassium. Focal electrical stimulation of the cortex (20 Hz), resulted in a significant (1.9 +/- 0.2-fold, n = 8) increase in the levels of CCK-LI. The addition of glutamate (10(-6)-10(-4) M) of kainic acid (10(-8)-10(-6) M), also resulted in significant elevations in the levels of CCK-LI. The co-administration of a putative glutamate receptor antagonist, kynurenic acid (10(-4) M) resulted in a significant reduction in the levels of release otherwise evoked by the addition of glutamate, but not by electrical stimulation. The addition of GABA (10(-5)-10(-3) M) resulted in a dose-dependent decrease in the resting release of CCK-LI, and the release evoked by glutamate. Picrotoxin (10(-6)-10(-4) M), resulted in a highly significant increase in the levels of CCK-LI in the cortical effluent. These results are consistent with a tonic GABAergic inhibition of CCK-releasing neurons. The treatment of the animal with diazepam (30 mg/kg, i.p.) also resulted in a significant reduction in resting release and the release otherwise evoked by focal cortical stimulation. 相似文献
78.
本文报道用高效液相色谱-电化学检测器方法,研究了罂粟碱对大鼠脑内及心脏单胺神经递质代谢的影响。结果表明:罂粟碱能显著增加大鼠纹状体及边缘区多巴胺代谢物二羟苯乙酸(DOPAC)和高香草酸(HVA),升高约50-70%。5-羟色胺代谢物5-羟吲哚醋酸(5HIAA)增加约30%,而对脑及心脏内的单胺递质本身含量未见有明显影响。 相似文献
79.
对14例 Graves 患者行碳酸锂~(131)碘—硫番酸三联疗法是放射性药物与非放射性药物联合应用的一种尝试,目的在不影响治愈率,又减少远期甲减发生率。本疗法是通过三个环节降低血 T_3、T_4水平控制甲状腺毒症。14例患者三联疗法一年结果治愈率为78.6%,有效率为100%。 相似文献
80.
目的 探讨不同器官保存液对大鼠肝脏透明质酸吸收率的影响 ,以评价它们对肝窦内皮细胞的保护作用。方法 大鼠肝脏原位灌洗后 ,分别在UW液、Celsior液或Histidine Tryptopan Ketoglutarate液 (HTK液 )中低温保存 16和 2 4h ,然后用含透明质酸的Kreb Henseleit液在 37℃下连续循环灌注 90min ,分别于灌注 0、15、30、6 0和 90min时检测肝脏对外源性透明质酸的吸收率。结果 低温保存 16h ,再灌注 0、15、30、6 0和 90min时 ,3种保存液保存的肝脏对外源性透明质酸的吸收率均为负值 ,表明肝窦内皮细胞受到一定程度的损伤 ,但UW液和Celsior液对肝窦内皮细胞的保护作用较HTK液为优 (P <0 .0 1) ;保存 2 4h者 ,UW液对肝窦内皮细胞的保护作用优于Celsior液和HTK液。结论 UW液对肝窦内皮细胞具有较强的保护作用 相似文献