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From a review of 131 children with arthrogryposis, we studied 18 patients with hip dislocations. Fourteen patients (10 unilateral, four bilateral) were treated by open reduction. Mean age at surgery was 9.7 months, and follow-up ranged from 9 to 245 months. Range of motion of patients treated by open reduction following the medial approach was greater than in those treated by anterolateral incision and greater than in bilateral cases treated by closed reduction. Acetabular development was satisfactory following the medial approach and there were no re-dislocations, but one hip developed avascular necrosis. 相似文献
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进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关 相似文献
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The purpose of this study was to determine the conditions for optimum synergistic efficacy of the two-drug combination of trimetrexate and 5-fluorouracil. Synergistic cell killing of Chinese hamster ovary cells in these clonogenic survival assays was observed only when the cells had been exposed to trimetrexate (25 microM) for 2 to 4 h prior to 5-fluorouracil exposure (either 125 or 250 microM). The schedule dependence of the observed synergy in vitro was closely linked to trimetrexate-induced changes in cellular 5-phosphoribosyl 1-pyrophosphate (PRPP) pools. Exposure to 25 microM trimetrexate induced increases in PRPP pools to 398% and 761% of control values at 2 and 4 h, respectively. Methotrexate (20 microM) also increased Chinese hamster ovary cell PRPP content in a time-dependent fashion to values of 280 and 511% of control after 2 and 4 h of drug exposure. Previous in vivo studies demonstrated a modest degree of therapeutic synergy between trimetrexate and 5-fluorouracil against P388 leukemia. Our in vitro results suggested that the degree of synergy seen in vivo could be increased with appropriate schedule changes. Mice were implanted i.p. with 10(6) P388 leukemia cells on Day 0 and were treated with trimetrexate (every 3 h for eight injections; Days 1, 5, and 9) and 5-fluorouracil (Days 1, 5, and 9) as single agents or in combination on one of two schedules; 5-fluorouracil was administered with either the first or the last of the eight trimetrexate doses on Days 1, 5, and 9. Both treatment regimens demonstrated therapeutic synergy but, as predicted from the in vitro data, the "5-fluorouracil last" was superior to the "5-fluorouracil first" sequence. Treatment with the optimal doses on the "5-fluorouracil last" sequence (trimetrexate, 31; 5-fluorouracil, 33 mg/kg/injection) produced an increased life span of 183% and a net reduction in tumor cell burden of 6.7 logs compared with a 111% increased life span (net reduction in tumor burden of 2.6 logs) produced by the most active of the single agents, 5-fluorouracil. Thus the efficacy of the combination of trimetrexate with 5-fluorouracil was sequence and time dependent both in vitro and in vivo. The synergy, observed in vitro and probably in vivo, was linked to a trimetrexate-induced elevation of intracellular PRPP, thus facilitating the production of 5-fluoropyrimidine nucleotides. These data are similar to the sequence and schedule dependency of the methotrexate/5-fluorouracil combination with important differences.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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Hydrolysis of peptides within lumen of small intestine 总被引:2,自引:0,他引:2
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Inhibition of Dugbe nairovirus replication by human MxA protein 总被引:6,自引:0,他引:6
Sensitivity to the interferon-induced protein, MxA, has previously been demonstrated for viruses belonging to the Orthobunyavirus, Hantavirus and Phlebovirus genera of the Bunyaviridae family. We have extended these findings to a member of the fourth and remaining genus containing viruses that infect man and other animals, the nairovirus Dugbe virus (DUGV). Indirect immunofluorescence experiments using VA9 cells (Vero cells permanently transfected with MxA cDNA) revealed strongly reduced DUGV antigen expression, suggesting that MxA inhibited DUGV replication. Western and Northern blot analyses showed significantly lower DUGV nucleocapsid (N) protein expression and DUGV genomic RNA, respectively, in the presence of MxA. Viral titres were also reduced by more than two orders of magnitude in VA9 cells compared with control VN36 cells. This finding may have application to nairovirus therapeutics. 相似文献
59.
Owens EB Hinshaw SP Kraemer HC Arnold LE Abikoff HB Cantwell DP Conners CK Elliott G Greenhill LL Hechtman L Hoza B Jensen PS March JS Newcorn JH Pelham WE Severe JB Swanson JM Vitiello B Wells KC Wigal T 《Journal of consulting and clinical psychology》2003,71(3):540-552
Using receiver operating characteristics, the authors examined outcome predictors (variables associated with outcome regardless of treatment) and moderators (variables identifying subgroups with differential treatment effectiveness) in the Multimodal Treatment Study of Children with Attention-Deficit/Hyperactivity Disorder (ADHD; MTA). Treatment response was determined using parent- and teacher-reported ADHD and oppositional defiant symptoms, with levels near or within the normal range indicating excellent response. Among 9 baseline child and family characteristics, none predicted but 3 moderated treatment response. In medication management and combined treatments, parental depressive symptoms and severity of child ADHD were associated with decreased rates of excellent response; when these 2 characteristics were present, below-average child IQ was an additional moderator. No predictors or moderators emerged for behavioral and community comparison treatments. The authors discuss conceptual and clinical implications of research on treatment moderators. 相似文献
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