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Tolk.  KA 《中国新药杂志》2000,9(8):565-569
目的:确定塞来昔布对于经常服用稳定剂量甲氨喋呤(MTX)治疗类风湿性关节炎(RA)患者的肾脏清除率和血浆药代动力学方面的影响。方法:选取14例至少已服用MTX3个月,且每个星期的剂量稳定在5-15mg,有类风湿关节炎的成年妇女,随机给予塞来昔布(200mg.bid)或安慰剂单盲治疗,每一阶段7,分二阶段交叉试验,研究MTX的药代动力学和肾脏平均清除率。结果:当MTX和塞来昔布或安慰剂合用时,MTX  相似文献   
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To determine the optimal dose of gamma radiation necessary to inhibit T- lymphocyte function and prevent transfusion-acquired graft-versus-host disease (TA-GVHD), a donor plateletpheresis component was initially divided into ten 20-mL samples. One sample was not irradiated, while the other nine samples were treated with gamma radiation at doses ranging from 500 to 4500 cGy. T-lymphocyte function was subsequently measured by mixed lymphocyte cultures and mitogen stimulation assays. The results were assessed in each test by calculating the percentage of inhibition of each irradiated sample as compared to that of the unirradiated sample. The accuracy of the delivered dose of gamma radiation was measured with thermoluminescent dosimeters. It was concluded that a nominal dose of 3000 cGy (actual dose delivered, 2898 cGy) is the appropriate amount of gamma radiation needed to eliminate T- lymphocyte-mediated graft-versus-host disease.  相似文献   
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Data from a 1980, community-based survey of adult residents of Edgecombe County, North Carolina were analyzed to examine differences between Blacks and Whites in the reported use of medical care after experiencing chest pain. Of all adults (N = 302) with chest pain in the year prior to interview, 49 percent of Blacks and 27 percent of Whites did not see a physician following the chest pain (difference = 22%, 95% CI = 12, 33). A multivariable analysis found that although the association between race and utilization was reduced at poverty levels of income, it was not explained by differences in demographic characteristics, health status or other dimensions of access to care.  相似文献   
99.
邵刚  吴芳  王德胜  朱荣  罗旭 《药学学报》1995,30(5):384-389
l-麻黄碱和d-伪麻黄碱是生药麻黄中早为人知而至今仍被广泛用于临床的一对手性异构生物碱。由于二者为生药麻黄中的主要成分但药理活性不同,为便于临床监控及有效用药,高分辨高灵敏度的检测方法的开发迫在眉睫。本文以易于得到的dansylchloride为柱前荧光标识试剂,在确定了最佳衍生化及分离条件的基础上,建立了理想的色谱分析系统(线性检测范围1~800ng·ml-1)。同时运用此方法,完成了对静注l-麻黄碱和d-伪麻黄碱后豚鼠血浆内该对手性异构体水平的考查,并且定量检测了服用中成药小青龙合剂后人血浆中的该对手性异构体。  相似文献   
100.
Wood  GA; Korkola  JE; Lee  VM; Sarma  DS; Archer  MC 《Carcinogenesis》1997,18(9):1745-1750
Copenhagen (Cop) rats are completely resistant to the chemical induction of mammary adenocarcinomas, but their susceptibility to hepatocarcinogenesis is virtually unknown. Rat liver is a well- characterized and easily manipulated tissue in which to study carcinogenesis. Therefore, if Cop rats are resistant to hepatocarcinogenesis, studies into resistance mechanisms may be feasible. Male Cop and F344 rats, 7-8 weeks old, were initiated using either N-nitrosodiethylamine (DEN) (200 mg/kg, i.p.) or a two-thirds partial hepatectomy (PH) followed by N-methyl-N-nitrosourea (MNU) (60 mg/kg, i.p.). The rats were then promoted using a modified resistant hepatocyte (RH) protocol (a combination of four doses of 2- acetylaminofluorene (2-AAF) and a single dose of CCl4 that provides a selective mitotic stimulus for initiated cells). Six weeks after initiation the rats were killed and liver sections were stained for glutathione S-transferase 7-7 (GST 7-7), a marker for putative preneoplastic hepatocytes. Cop rats were found to be highly resistant, having a approximately 9- and approximately 27-fold smaller percentage of liver area occupied by GST 7-7-positive foci than susceptible F344 rats following initiation by DEN and MNU respectively. Furthermore, gross liver nodules did not form in any of the Cop rats, whereas all F344 rat livers contained nodules. Hepatic necrosis caused by DEN during initiation, and CCl4 during promotion is necessary to stimulate compensatory hepatocyte division. We demonstrated that these agents do indeed increase serum transaminase levels and produce histologic evidence of necrosis in Cop rats. In order for liver foci to grow rapidly in the RH protocol, the surrounding normal hepatocytes must be mito-inhibited by 2-AAF. We found that the degree of mito-inhibition of normal hepatocytes by 2-AAF is the same in Cop and F344 rats. These results show that the Cop rat is highly resistant to the chemical induction of putative preneoplastic liver foci and nodules.   相似文献   
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