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1The aim of this study was to assess the pharmacokinetics, clinical efficacy and safety of artemisinin alone and in combination with mefloquine. 2Thirty-eight adults with symptomatic Plasmodium falciparum malaria were randomly assigned to receive either artemisinin (500 mg single dose followed by another 500 mg on day 1 and then 250 mg twice daily for 4 days) or artemisinin (500 mg single dose followed by 750 mg on day 1 and then 250 mg three times daily for one more day) in co-administration with mefloquine (250 mg three times daily for the first day). All drug administration was by the oral route. Patients were hospitalized at the Kibaha Designated District Hospital, Kibaha, Tanzania, for 6 days and a follow up for 3 weeks was performed. 3Treatment with the artemisinin/mefloquine combination resulted in a shorter parasite clearance time (PCT) of 24 (22, 27; 95% confidence interval) h vs 31 (27, 36) h and fever subsidence time (FST) of 14 (12, 16) h vs 20 (18, 23) h compared with artemisinin monotherapy. The 95% CI for the difference of the PCT and FST were 1.7, 12 and 3, 10, respectively. Parasites were detected in 7 out of 17 patients (41%) receiving artemisinin monotherapy at the 3rd and 4th week follow up visits. No parasites were detected after the combination therapy. 4The maximum plasma concentrations ( Cmax) were similar after artemisinin monotherapy (615.4±387.0 ng ml−1) and in combination with mefloquine (851.8±523.6 ng ml−1). Elimination half-lives (t1/2) were also identical at 2.2±0.6 h and 2.5±0.7 h, respectively. However, the AUC values were higher ( P<0.05) after combination therapy (3252±1873 ng  ml−1 h) than after monotherapy (2234±1502 ng ml−1 h). The oral clearance values were lower ( P<0.05) after combination therapy (195.4±86.9 l h−1) than after monotherapy (314.3±189.4 l h−1). PCT and FST normalized to initial parasitaemia correlated with AUC(0,  t) (rs=0.56, P=0.02, rs=0.58, P=0.01, respectively) and with Cmax (rs=0.62, P=0.01, rs=0.68, P=0.005, respectively) in the artemisinin monotherapy only. 5One patient on the combination therapy developed a psychiatric condition and two patients on the monotherapy developed skin itch.  相似文献   
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Summary. Mitotane (o,p'-DDD) can be used for the treatment of various adrenocortical diseases such as Cushing's syndrome, but the usual doses of 6–8 g per day are often associated with severe adverse effects.This paper reports the results of much lower doses of o,p'-DDD (0.5–2 g per day) in two patients with Cushing's disease over periods of 8 and 5 years, respectively, under concomitant monitoring of the plasma levels of the parent drug and its major metabolite, o,p'-DDE.It became apparent that o,p'-DDD and o,p'-DDE have a strong tendency to accumulate in the body due to their high lipophilicity. As a consequence, changes in dose regimens had long lag times before they were reflected in plasma levels and once an increase or decrease had started one had to be careful not to cause overshoot.Steady state plasma levels of o,p'-DDD between 5–10 g/ml appeared sufficient to induce and to maintain remission of the disease, which was accompanied with normal cortisol levels in plasma and urine. DDD-levels below 5 g/ml for several weeks may lead to relapses, whereas DDD-levels over 10 g/ml gave rise to side effects. On the other hand, o,p'-DDE seemed inactive at levels up to 4 g/ml in plasma.  相似文献   
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Long-chain polyunsaturated fatty acids (LCP) are thought to be required for optimal nervous system development in the newborn. A commercial milk formula containing LCP (Aptamil-LCP) with a fatty acid profile closely resembling breast milk, has recently been introduced for term infants. The absorption of fatty acids in term infants was examined in a double-blind randomized controlled trial comparing Aptamil-LCP ( n = 20) and standard Aptamil ( n = 20). Formula-fed newborn infants were studied from birth for 14 d. Fat balances (3 d) were performed from d 10. A 3-d stool collection was performed from d 10 in a parallel breastfed group ( n = 21). Plasma samples were taken on d 6. Median fat excretion (mg kg−1) was 897.1, 615.0 and 355.2 with Aptamil, Aptamil-LCP and breastfeeding, respectively. The median total fat absorption coefficient in Aptamil-LCP-fed infants was higher than in those fed standard Aptamil ( p < 0:01). These findings were accounted for by differences in the excretion and absorption of long-chain saturated fatty acids (C14:0, C16:0 and C18:0). Higher fat excretion was associated with bulkier and firmer stools. Only trace amounts of LCP were detected in the stools of all groups. This accounted for less than 4% of dietary intake in Aptamil-LCP-fed infants. No differences in the utilization of LCP from Aptamil-LCP and breast milk feeding were apparent. Plasma phospholipid fatty acid composition data reflected differences in dietary LCP intake. Thus, PL LCP levels were highest in the breastfed infants and lowest in the Aptamil-fed infants, with values for the Aptamil-LCP-fed group falling in between.  相似文献   
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To investigate the mechanism of chronic cell death following postischemic hypothermia, the change of N-methyl- -aspartate receptor (NMDAR) were examined by immunohistochemistry of NMDAR1 and long-term potentiation (LTP) in the CA1 subfield of the gerbil hippocampus. At 1 week following postischemic hypothermia (32°C×4 h), all CA1 neurons survived; however, immunoreactivity of NMDAR1 increased in neuronal perikarya whereas decreased in dendrites in the CA1 neurons. The abnormality was still observed in remaining CA1 neurons at 1 month after hypothermia. LTP was also significantly depressed at 1 week after hypothermia. These results suggest that some abnormalities in the glutamate receptor may be caused by ischemia; such abnormality would persist in spite of hypothermia treatment, resulting in the depression of LTP.  相似文献   
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目的:观察柴黄益肾方提取物(CYE)对大鼠的长期毒性,为临床安全用药提供依据.方法:将大鼠随机分为4个组,3个剂量组分别按8.8g/kg、4.4g/kg、2.2g/kg连续灌胃给予CYE 6个月,对照组给予同体积生理盐水.停药后继续观察4周,测试大鼠体重、血液学指标、血液生化学指标、脏器指数及病理组织学变化.结果:高剂量组大鼠体重增长缓慢,3个剂量组与红细胞相关指标与对照组比较小幅下降,尿素氮与对照组比较小幅上升,高中剂量组肝脏指数小幅上升,与对照组比较有显著性差异,以上改变均在正常生理范围之内.结论:CYE在临床推荐剂量下有一定的安全性.  相似文献   
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目的探讨美宝湿润烧伤膏(MEBO)配合微波治疗宫颈糜烂的效果。方法2005年10月~2007年6月,173例宫颈糜烂患者随机分为A、B两组,月经干净后3~7天,均采用WNZ普通型微波治疗仪治疗,微波输出功率为50W。A组(89例)单纯采用微波治疗,B组(84例)先用微波治疗,治疗后创面局部涂抹MEBO,2个月内避免盆浴,4个月内禁止性生活。结果A、B两组中,轻度糜烂Ⅰ°组单纯采用微波治疗有效率94.7%,合用MEBO有效率100%,两组无明显差异,而痊愈率A组为71.0%,B组加用MEBO高达86.8%,经x2检验P<0.05,差异有显著性。在Ⅱ°、Ⅲ°单纯微波治疗中,A组有效率分别为62.2%和42.9%,痊愈率分别为16.2%和0%,B组经加用MEBO,其有效率分别为100%和85.7%,痊愈率分别为75%和35.7%,经x2检验P<0.01,差异有高度显著性。结论MEBO配合微波治疗可明显提高宫颈糜烂临床治疗效果。  相似文献   
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