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European Journal of Nutrition - The French Nutri-Bébé 2013 study aimed to assess the nutritional intake of infants and young children in comparison with the recommendations of the 2013...  相似文献   
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The objective of this study was to assess the in vivo fate of poly(2-(dimethylamino)ethyl methacrylate) (pDMAEMA)-based polyplexes after intravenous administration into mice. Circulation kinetics and tissue distribution in terms of plasmid localization and transfection efficiency were assessed. To gain more insight into the observed biodistribution and gene expression profile, the interaction of pDMAEMA-based polyplexes with blood components (erythrocytes and albumin) was investigated in vitro. In the case of i.v. injection of positively charged polyplexes at a dose of 30 microg DNA most of the radioactivity was found in the lungs and the liver 60 min after injection. In the case of pDMAEMA/DNA polyplexes with a negative charge, uptake occurred mainly by the liver. Administration of positively charged complexes at a 30 microg DNA dose resulted in reporter gene expression primarily in the lungs. Injection of negatively charged complexes and naked plasmid did not result in luciferase expression in any of the organs examined. In vitro turbidity experiments showed the induction of a charge dependent aggregation process upon addition of albumin to the polyplexes pointing out to the involvement of aggregate formation in the dominant lung uptake of the positively charged polyplexes. Also, incubations of polyplexes after pre-incubation with a physiological concentration of albumin with washed erythrocytes confirmed that polyplexes induce the formation of extremely large structures. This paper underlines the need for the design of systems with reduced interaction with blood components to promote the delivery of DNA to target tissues outside the lungs.  相似文献   
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A randomized two-way crossover study was conducted in 12 healthy volunteers to assess the effect of food on the pharmacokinetics of quinapril (CI-906) and its active metabolite, CI-928, after quinapril dosing. Forty-milligram oral quinapril doses were administered in a fasted or a fed state with a one-week washout period between treatments. No significant treatment differences were observed in quinapril and CI-928 values for maximum plasma concentration, area under the plasma concentration-time curve, or percentage of dose excreted in the urine. Small but significant increases of less than 0.5 hour in quinapril and CI-928 tmax values were observed after consumption of food. The pharmacokinetic profiles of quinapril and CI-928 were not significantly altered by the administration of food.  相似文献   
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硫酸多糖对体外人脐静脉内皮细胞损伤的保护作用   总被引:8,自引:1,他引:7  
研究表明,硫酸多糖体外对多聚阳离子和氧自由基损伤的人脐静脉内皮细胞有保护作用。肝素、硫酸软骨素A抗多聚阳离子损伤作用比同浓度低分子肝素和甘糖酯强。肝素、硫酸软骨素A、甘糖酯抗氧自由基损伤作用优于同浓度低分子肝素。结果显示硫酸多糖有保护血管内皮的作用,其作用可能与所带阴离子基团有关。  相似文献   
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A simple, precise method has been developed for assessing neutrophil secretory responses (release of vitamin B12 binding protein from specific granules) to challenge of aliquots of whole blood with the bacterial chemotactic peptide N-formylmethionyl-leucyl-phenylalanine (fMLP). Dose-response studies performed on blood from normal healthy volunteers showed higher maximal secretory responses in males than females (33.3 +/- SEM 2.2 vs. 27.4 +/- 2.5, P less than .005) a left shift in dose-response curves after feeding compared to fasting (P less than .005), spontaneous up-regulation of responses in blood incubated at 37 degrees C for 1 h, and marked upregulation in response to preincubation with endotoxin. This whole blood challenge method may be used to study neutrophil responses in groups of individuals or patients without the confounding effects of changes in cell responses resulting from cell isolation procedures. The method may also be used as a bioassay for neutrophil-activating factors.  相似文献   
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Cisplatin and its analogs have become important components of chemotherapeutic regimens for the treatment of solid tumors, however, their overall effectiveness is limited by the emergence of drug-resistant tumor cells. Resistance to the platinum drugs is multifactorial consisting of mechanisms that prevent the formation of lethal platinum-DNA adducts and mechanisms that operate downstream of the drug/target interaction to promote cell survival. Continued progress in the study of the drug resistance phenotype as well as the development of new platinum analogs may eventually lead to improved therapies and increased survival rates.  相似文献   
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Summary: The objective of this study was to assess the efficacy and safety aspects of performing transcervical endometrial resection (T.C.R.E.) on a selected group of 278 patients with menstrual disorders under local analgesia (intracervical block) only. Patient acceptance of the procedure was high, with only 3 cases not completed due to insufficient analgesia (1.07%), although a further 9 (3.2%) were completed with the help of intravenous sedation. Patient satisfaction at 4 months was 90%. There were 4 perforations (1.4%), but no laparotomy was required. Five cases (1.7%) of haemorrhage required a Foley catheter, with 1 needing a transfusion. There was no case of clinically evident glycine overload. Twelve patients required an overnight stay.
Patient acceptance of T.C.R.E. under local analgesia, and the incidence of major complications, compared favourably with other published series, including a series of 330 cases performed concurrently by the same operators under general anaesthesia.  相似文献   
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