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111.
In vitro metabolic study of temsirolimus: preparation, isolation, and identification of the metabolites. 总被引:1,自引:0,他引:1
The in vitro metabolism of temsirolimus, (rapamycin-42-[2,2-bis-(hydroxymethyl)]-propionate), an antineoplastic agent, was studied using human liver microsomes as well as recombinant human cytochrome P450s, namely CYP3A4, 1A2, 2A6, 2C8, 2C9, 2C19, and 2E1. Fifteen metabolites were detected by liquid chromatography (LC)-tandem mass spectrometry (MS/MS or MS/MS/MS). CYP3A4 was identified as the main enzyme responsible for the metabolism of the compound. Incubation of temsirolimus with recombinant CYP3A4 produced most of the metabolites detected from incubation with human liver microsomes, which was used for large-scale preparation of the metabolites. By silica gel chromatography followed by semipreparative reverse-phase high-performance liquid chromatography, individual metabolites were separated and purified for structural elucidation and bioactivity studies. The minor metabolites (peaks 1-7) were identified as hydroxylated or desmethylated macrolide ring-opened temsirolimus derivatives by both positive and negative mass spectrometry (MS) and MS/MS spectroscopic methods. Because these compounds were unstable and only present in trace amounts, no further investigations were conducted. Six major metabolites were identified as 36-hydroxyl temsirolimus (M8), 35-hydroxyl temsirolimus (M9), 11-hydroxyl temsirolimus with an opened hemiketal ring (M10 and M11), N- oxide temsirolimus (M12), and 32-O-desmethyl temsirolimus (M13) using combined LC-MS, MS/MS, MS/MS/MS, and NMR techniques. Compared with the parent compound, these metabolites showed dramatically decreased activity against LNCaP cellular proliferation. 相似文献
112.
J F Cai 《中华整形烧伤外科杂志》1989,5(3):190-2, 238
Since 1985, on the basis of anatomic study of dorsal pedal artery, thumb and radial side of palm reconstruction have been successfully performed in one stage by using opposite composite dorsal pedal flap including the second toe, the second metatarsal and the first toe web. Because they were all distributed by dorsal pedal artery and great saphenous vein, dissecting these tissues was not difficult. Good function and cosmetic appearance were achieved following reconstruction. 相似文献
113.
氧化亚氮联合利多卡因行无痛人工流产术280例临床分析 总被引:1,自引:0,他引:1
目的: 探讨吸入 50%氧化亚氮 (N2O) 与 50%氧气 (O2 ) 的混合气体联合宫颈注射 2%利多卡因进行无痛人工流产术 (人流术) 的有效性和安全性。方法: 将人流术 580例分为A、B两组。其中A组 280例吸入 50%氧化亚氮 (N2O)与 50%氧气的混合气体联合宫颈注射 2%利多卡因进行无痛人流术, 称为联合组; B组 300例, 不用任何药物, 为对照组, 分析比较两组手术中镇痛效果, 宫口松弛情况, 手术出血量, 人流综合反应。结果: 联合组镇痛完全, 有效率达 97 5%。宫口完全松弛率 97 9%。两组比较有显著性差异 (P<0 05)。结论: 吸入氧化亚氮联合宫颈注射利多卡因进行无痛人流术, 镇痛效果确定, 人流时受术者意识处于朦胧状态, 安静, 无痛苦, 不良反应少, 苏醒快等。 相似文献
114.
[目的]为进行自体外周血造血干细胞移植的病人提供优质护理,采集足够数量的造血干细胞,降低术中及术后不良反应。[方法]采用COBE Spectra血细胞分离机采集造血干细胞在采集前严密观察病人心理和血常规的变化,维持病人心理状态的稳定,掌握干细胞采集的最佳时机;术中严密观察生命体征、意识、四肢口唇是否有麻木感;术后监测病人外周的穿刺部位是否有出血,有无手足抽搐。[结果]20例病人均采集足够数量的造血干细胞,无不良反应发生:[结论]优质护理为自体外周血造血干细胞移植的成功奠定了基础。 相似文献
115.
中医药干预治疗难治性肾病综合征研究进展 总被引:1,自引:0,他引:1
难治性肾病综合征(RNS),是指原发性肾病综合征经过强的松标准治疗无效者或经强的松的标准疗程治疗能缓解,但经常复发(1年内复发3次或半年内发作超过2次以上)者,约占原发性肾病综合征的39.9%-53.8%,目前西医常采用激素和细胞毒药物治疗,虽近期取得一定的疗效,但易复发并存在诸多副作用。鉴于此,临床医学研究者对中医药干预治疗难治性肾病综合症的研究越来越多,并积累大量的经验,本文就近5年来其有关文献综述如下。 相似文献
116.
留置导尿管引起的相关感染(CAUTI)是临床上常见的医源性感染。由于肾移植病人的免疫抑制状态以及肾移植术后常规留置导尿管,导致CAUTI的发生率一直较高。而CAUTI的早期发现,病原菌的早期分离成为临床护理工作中需要高度再视的问题。回顾性分析我中心2004年8月-2005年8月72例肾移植病人的CAUTI检出情况,报道如下。 相似文献
117.
目的评价美国强生VITROS250全自动干化学分析仪器。方法运用相关统计学方法对VITROS250全自动干化学分析仪的精密度、相关性、抗胆红素干扰方面进行分析。结果VITROS250全自动干化学分析仪精密度高,回收率高,相关性好,抗干扰能力强。结论VITROS250全自动干化学分析仪适用于临床实验诊断中心(检验科)急诊化验室生化项目的检测。 相似文献
118.
A Batak Indonesian from North Sumatra with hemoglobin (Hb) D Punjab (alpha 2 beta 2 121----Gln) and hemoglobin Constant Spring (Hb CoSp) is described. The 24-year-old man did not have clinical symptoms, and his hematological indices were normal. However, he had a persistent slight elevation of fetal hemoglobin level. His mother and his brother were heterozygous for Hb D Punjab; his father had Hb CoSp trait. A sister did not have any abnormal hemoglobin. To show the exact molecular defect leading to the synthesis of Hb CoSp in this family, genomic DNA from the father was analyzed by hybridization with synthetic oligonucleotides. Genomic DNA was digested with Sst I and Hind III producing a 1.05-kb fragment from the 3' end segment of the alpha 2-globin gene, including the termination codon. Two nonadecamers were synthesized to serve as probes: one, entirely homologous to the normal 3' end of alpha 2A-globin gene sequence, including the termination codon TAA, the other different from it by a replacement of the T in the termination codon TAA with C, changing it to CAA, the codon for the amino acid glutamine. DNA from normal controls gave a positive signal with the normal alpha 2TAA oligonucleotide probe but negative with the alpha 2 CAA probe. The father of propositus who had Hb CoSp trait gave a positive signal with the normal alpha 2TAA oligonucleotide probe as well as with the alpha 2CAA oligonucleotide probe, showing him to be heterozygous for the alpha 2CAA-globin gene. This result shows that the Hb CoSp in the Batak family is indeed due to a replacement of T by C in the TAA termination codon of the alpha 2-globin gene changing it to CAA the condon for glutamine. This explains the resulting readthrough of the untranslated sequence of the mRNA. 相似文献
119.
CAILU LIUSHUZHENG 《Biomedical and environmental sciences : BES》1992,5(1):46-52
Human lymphocytes pre-exposed to 10 mGy or 50mGy of X-rays become less sensitive to subsequent large dose irradiation,exhibited lower rate of chromosome aberration than expected.This adaptive response could be inhibited by cycloheximide,a protein synthesis inhibitor for successive 2h period ranging from 0.5h before to 4h after the low dose exposure,indicating that the adaptive response was directly related with the protein synthesis. 相似文献
120.
动态观察实验性糖尿病大鼠于发病后2、4、6、12、和16周肾脏损害指标和肾脏脂质过氧化物(LPO)水平的变化。结果表明,发病后各观察时间.或糖尿病大鼠24h尿Alb、β2──MG排泄量和尿NAG活性均明显增高,而24h尿THP排泄量显著降低,肾脏LPO水平明显升高。其中尿NAG活性、THP排泄量和肾脏LPO水平均随病程延长而更趋明显。这些结果提示,在糖尿病早期除有肾小球功能损害外,肾小管也明显受损,过氧化损伤在糖尿病肾病发病中可能是重要因素之一。尿Alb、β2──MG、THP含量和NAG活性可作为糖尿病肾病早期肾损害的敏感指标。 相似文献