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991.
Arzamastsev A. P. Kondratenko S. N. Starodubtsev A. K. Blinkov I. L. Serebrova S. Yu. 《Pharmaceutical Chemistry Journal》2003,37(3):128-131
Pharmaceutical Chemistry Journal - 相似文献
992.
993.
Arzamastsev A. P. Sadchikova N. P. Luttseva T. Yu. Ramenskaya G. V. Korolev A. V. Brown W. Williams R. 《Pharmaceutical Chemistry Journal》2003,37(10):550-555
Pharmaceutical Chemistry Journal - 相似文献
994.
ZHANG Guang-Qin HAO Xue-Mei DAI De-Zai FU Yu ZHOU Pei-Ai WU Cai-Hong Research Division of Pharmacology China Pharmaceutical University Nanjing China ~National Laboratorv of Biomembrane Membrane Biotechnology College of Life Sciences Peking University Beijing China 《Acta pharmacologica Sinica》2003,(12)
AIM: To study the effect of puerarin (Pue) on Na~+ channel in rat ventricular myocytes. METHODS: Whole-cell patch-clamp technique was applied on isolated cardiomyocytes from rats. RESULTS: Pue inhibited cardiac I_(Na) in a positive rate-dependent and dose-dependent manner, with an IC_(50) of 349 μmol/L. The kinetics of blockage of cardiac sodium channel by Pue resembled the ClassIa/Ic of antiarrhythmic agents. Pue 300 μmol/L did not alter the shape of the I-V curve of I_(Na), but markedly shifted the steady-state inactivation curve of I_(Na) towards more negative potential by 15.9 mV, and postponed the recovery of I_(Na) inactivation state from (21.9±1.6) ms to (54.4±3.4) ms (P<0.01 ). It demonstrated that the steady state of inactivation was affected by Pue significantly. CONCLUSION: Pue protected ventricular myocytes against cardiac damage and arrhythmias by inhibiting recovery from inactivation of cardiac Na~+ channels. 相似文献
995.
Interleukin-6 activates phosphatidylinositol-3 kinase, which inhibits apoptosis in human prostate cancer cell lines 总被引:8,自引:0,他引:8
BACKGROUND: A number of recent studies have identified interleukin (IL)-6 as an important regulator of prostate cancer growth. Here, we investigate the potential interaction of IL-6 with phosphatidylinositol (PI)-3 kinase, a key growth regulatory enzyme, in prostate cancer cell lines. METHODS: Tyrosine phosphorylation of p85, the regulatory subunit of PI-3 kinase, in the human prostate cancer cell lines LNCaP and PC-3 was assessed by sequential immunoprecipitation with anti-p85 antibody and immunoblotting with anti-phosphotyrosine. The effects of wortmannin, an inhibitor of PI-3 kinase, and/or IL-6 on cell growth were assessed by MTT assays. DNA laddering experiments were performed to assay for programmed cell death. RESULTS: Tyrosine phosphorylation of p85 is upregulated by IL-6 in both LNCaP and PC-3. IL-6 promotes coprecipitation of p85 with gp130, the signal-transducing component of the IL-6 receptor. Inhibition of PI-3 kinase with wortmannin induces programmed cell death in PC-3 cells. In contrast, wortmannin has no effect on LNCaP growth when used alone; however, combined with IL-6, wortmannin promotes apoptosis in these cells. CONCLUSIONS: PI-3 kinase is involved in IL-6 signal transduction and delivers an antiapoptotic signal in human prostate cancer cell lines. 相似文献
996.
Time-dependent astroglial changes after gamma knife radiosurgery in the rat forebrain 总被引:11,自引:0,他引:11
OBJECTIVE: Using an experimental rat model and a clinically relevant treatment dose, we performed gamma knife radiosurgery to define the hyperacute radiation effects in normal rat forebrain, the time dependence of the astrocytic reaction, and the participation of astrocytes in the healing process after single-dose gamma radiation injuries. METHODS: Seventy-one rats underwent radiosurgical treatment (4-mm collimator) of the caudate-putamen nucleus (single-fraction maximal dose of 100 Gy) and were killed at times ranging from 3 hours to 90 days. Serial cryostat brain sections were processed with the immunohistochemical avidin-biotin complex technique, using anti-glial fibrillary acidic protein as the primary antibody (to identify astrocytes). RESULTS: Vascular changes, including endothelial hyperplasia and vessel wall thickening, were identified as the earliest postradiation manifestations and continued throughout the observation period. Astrocytes reacted to the radiation injury with hyperplasia and hypertrophy. At earlier time points (3-24 h), proliferation was the predominant reaction. The expression of glial fibrillary acidic protein in the proliferating and hypertrophic astrocytes formed an initial peak in the adjacent corpus callosum 3 days after radiosurgery and peaked within the target site between 14 and 30 days. Astrocytic proliferation and hypertrophy were also observed in distant cortices (frontal, parietal, insular, and piriform cortices) and in the hippocampus. No necrosis was observed less than 30 days after irradiation. By Day 90, necrotic lesions with a mean diameter of 4 mm were identified, with glial scar at their peripheries. Astrocytic morphological features varied according to the distance from the necrosis. The irradiated side contained more glial fibrillary acidic protein-containing cells than did the nonirradiated contralateral side. CONCLUSION: During the early phase after radiation, vasculopathy was the first morphological change and may serve as the initiating factor for subsequent changes. Reactive astrocytes appeared not only at the target site but also in the surrounding regions; the severity of injury was determined by the distance from the target. 相似文献
997.
针药结合治疗周围性面瘫200例 总被引:1,自引:0,他引:1
目的观察针药结合治疗周围性面瘫的疗效。方法将200例周围性面瘫病人按病位、病程、年龄、是否用药饼灸分为4组。观察以上闪素对疗效的影响。结果病位越低、病程越短、年龄越小。用药饼灸疗效越好。 相似文献
998.
999.
新型药物开发制备过程中,需要对药物颗粒进行粒子设计,通过多层微胶囊化而得到复合包覆药物颗粒。药物包覆、微胶囊制备方法很多,可分为化学法、物理化学法、物理法。本文着重介绍了制备复合多层包覆药物颗粒的几种物理机械方法:复合杂化系统,高速椭圆转子混合法、喷流床包覆法。简要分析了该技术用于中药现代化加工的可能性。 相似文献
1000.
目的 探讨胃肠术后 1号治疗急性弥漫性腹膜炎的疗效。方法 测定 2 0例急性弥漫性腹膜炎患者 (随机分为 2组 :对照组 10例 ,治疗组 10例 )血中乳酸、DAO水平。结果 急性弥漫性腹膜炎患者血中乳酸、DAO呈现不同程度升高 ,经治疗随病情好转 ,血中乳酸、DAO呈现不同程度下降 ,而治疗组血中乳酸、DAO下降幅度显著 ,优于对照组 (P <0 .0 5 )。结论 血中乳酸、DAO在急性弥漫性腹膜炎患者病理过程中起重要作用 ,可作为评估急性弥漫性腹膜炎患者严重程度的指标 ,胃肠术后 1号使乳酸、DAO水平下降 ,促进疾病恢复 相似文献