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81.
Ras farnesyltransferase inhibitors suppress the phenotype resulting from an activated ras mutation in Caenorhabditis elegans. 总被引:1,自引:0,他引:1
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M Hara M Han 《Proceedings of the National Academy of Sciences of the United States of America》1995,92(8):3333-3337
Attachment of Ras protein to the membrane, which requires farnesylation at its C terminus, is essential for its biological activity. A promising pharmacological approach of antagonizing oncogenic Ras activity is to develop inhibitors of farnesyltransferase. We use Caenorhabditis elegans vulval differentiation, which is controlled by a Ras-mediated signal transduction pathway, as a model system to test previously identified farnesyltransferase inhibitors. We show here that two farnesyltransferase inhibitors, manumycin and gliotoxin, suppress the Multivulva phenotype resulting from an activated let-60 ras mutation, but not the Multivulva phenotype resulting from mutations in the lin-1 gene or the lin-15 gene, which act downstream and upstream of let-60 ras, respectively, in the signaling pathway. These results are consistent with the idea that the suppression of the Multivulva phenotype of let-60 ras by the two inhibitors is specific for Ras protein and that the mutant Ras protein might be more sensitive than wild-type Ras to the farnesyltransferase inhibitors. This work suggests that C. elegans vulval development could be a simple and effective in vivo system for evaluation of farnesyltransferase inhibitors against Ras-activated tumors. 相似文献
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83.
目的 对比观察头孢噻肟(CTX)与其他两种抗菌药物治疗方案对30例血液病合并感染患者杀 菌活性(SBA)及临床疗效。方法SBA采用微量稀释法测定,临床疗效根据临床治疗登记表按三 级标准判定。结果与结论 头孢噻肟的临床反应最佳,杀菌作用时间维持较长,但对绿脓假单胞 菌和阴沟肠杆菌杀菌作用较差;呱拉西林(PIP)与阿米卡星(AN)方案的抗菌谱广,但PIP杀菌 作用时间较短,可考虑缩短给药间期,而AN可按一日一次给全日量的方案,以提高疗效减少不 良反应;头孢哌酮(CPZ)可主要用于绿脓假单胞菌感染,也可用于其它细菌的混合感染,但给药 间隔时间以一日三次为宜。 相似文献
84.
Jung Han Kim Sang Jun Lee Young Bok Han Jung Jo Moon Jong Bae Kim 《Archives of pharmacal research》1994,17(2):115-118
This paper describes the isolation of isoguanosine from Croton tiglium L. and its cytotoxic effect against several tumor cell lines in culture and newly reports that isoguanosine has an antitumor activity against implanted S-180 ascitic tumor mice. Isoguanosine is effective at the dose of 24 mg/kg/day x 5, with T/C value of 168%. Isoguanosine inhibits the growth of S-180 and Ehrlich solid tumor in mice at the optimal doses of 96 mg/kg/day x 12 and 48 mg/kg/day x 12, with 1-T/C values of 65% and 60%, respectively. 相似文献
85.
从芫花Daphne genkwa条的乙酸乙酯可溶部分分到3个结果性化合物,借助于波谱分析手段推断出Ⅱ为西瑞香素,Ⅲ为daphnodorin B。 相似文献
86.
山莨菪碱防治甘油所致急性肾功能衰竭的实验研究 总被引:2,自引:0,他引:2
在129只SD大鼠的实验中动态观察了山莨菪碱对甘油所致急性肾功能衰竭时不同时期的Bcr,BUN,pH病理改变及死亡率的影响,结果表明:山莨菪碱能降低ARF第5天大鼠死亡率以及Bcr,BUN水平。改善病理损害,对ARF起到预防及治疗效果,山莨菪碱的预防效果优于治疗效果,预防是ARF防治的关键,但山莨菪碱在治疗过程中要引起“冲刷综合征”导致洗脱性酸中毒,应引起注意。 相似文献
87.
用带血管的胎儿甲状旁腺移植术治疗甲状旁腺机能低下症,共行手术6次(腹腔内移植5次,股三角区移植1次),6次中有3例术后发生4次排斥反应。经1年8月至3.5年随防,疗效显著者2例,有效2例,失败1例。本文讨论了有关甲状旁腺移植的手术方法、注意事项、免疫抑制剂应用等问题。 相似文献
88.
89.
Jong-Moon Lee Kun-Woo Park Woo-Keun Seo Moon Ho Park Changsu Han Inho Jo Sangmee Ahn Jo 《Movement disorders》2007,22(16):2446-2449
There have been a few studies and inconsistent results regarding the coincidence of Parkinson's disease (PD) and atherosclerotic diseases, such as cerebrovascular disease. Carotid intima-media thickness (IMT) is a known marker for subclinical atherosclerosis. The aim of this study was to investigate the carotid IMT between PD patients and controls. We studied 43 patients with PD and 86 matched controls. The carotid IMT in PD patients was significantly smaller than in controls (0.796 +/- 0.179 mm vs. 0.913 +/- 0.237 mm, P < 0.05). In multivariate analysis, the carotid IMT was inversely associated with the duration of levodopa medication and the severity of PD. These results suggest that PD patients have a lower risk of atherosclerosis. 相似文献
90.
Paired kidney analysis of tacrolimus and cyclosporine microemulsion-based therapy in Chinese cadaveric renal transplant recipients 总被引:5,自引:0,他引:5
Chi Yuen Cheung Kim Ming Wong Hoi Wong Chan Yan Lun Liu Yiu Han Chan Ho Sing Wong Wai Leung Chak Koon Shing Choi Ka Foon Chau Chun Sang Li 《Transplant international》2006,19(8):657-666
Few studies used paired kidneys for comparison between tacrolimus and cyclosporine in renal transplantation. Most of the published data used whole blood trough levels for drug monitoring. However, the use of limited sampling strategy and abbreviated formula to estimate the 12-h area under concentration-time curve (AUC(0-12)) allowed better prediction of drug exposure. Sixty-six first cadaveric renal transplant recipients receiving paired kidneys were randomized to receive either tacrolimus-based (n = 33) or cyclosporine microemulsion (Neoral)-based therapies (n = 33). Abbreviated AUC(0-12) was used for drug monitoring and dose titration. Mean follow-up duration was 2.8 +/- 2 years. The patient and graft survival were comparable. Fewer incidence of acute rejection was observed in tacrolimus group (15% vs. 27.3%) though the difference was not significant (P = 0.23). The absolute value and the rate of decline of creatinine clearance were both significantly better in tacrolimus-treated patients. Prevalence of hypertension, post-transplant diabetes mellitus, infection, and malignancy were similar in both groups. Prevalence of hypercholesterolemia (11/33 vs. 4/33) and gum hypertrophy (6/33 vs. 1/33) was more common in cyclosporine-treated patients (P = 0.04 in both parameters). This was the first prospective, randomized study with paired kidney analysis showing the renal function was significantly better in tacrolimus-treated patients than in cyclosporine-treated patients. 相似文献