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排序方式: 共有856条查询结果,搜索用时 15 毫秒
41.
BA DARLOW TE INDER KB SLUIS G NUTHALL N MOGRIDGE CC WINTERBOURN 《Journal of paediatrics and child health》1995,31(4):339-344
Objective: New Zealand soils are deficient in the essential micronutrient, selenium. New Zealand infants have low selenium levels at birth and experience a further decline if fed cows milk based formula. This study examined the selenium status of infants fed with a new commercially available selenium supplemented formula.
Methodology Forty-four newborn infants, whose mothers wished to formula feed, were randomized in an open controlled trial to be fed a commercially available selenium supplemented cows milk formula (containing 17 μg Se/L) or an unsupplemented formula (containing 4.6 μg Se/L). Cord, 1 and 3 month blood samples were obtained for selenium status (plasma and red cell selenium and glutathione peroxidase) and thyroid function.
Results Mean plasma selenium and glutathione peroxidase values were significantly higher in supplemented than unsupplemented infants at 1 month (unpaired t -tests; P <0.0001 and P = 0.001 respectively) and 3 months ( P <0.0001 and P = 0.0005). Analysis within treatment groups between time points (paired t -tests) showed that selenium supplementation prevented the fall in plasma selenium from birth to 1 month seen in unsupplemented infants and was associated with a rise in levels between 1 and 3 months ( P = 0.002).
Conclusions Supplementing cows milk formula with selenium to replicate the levels found in breast milk is nutritionally sound. Feeding from a few days of age with a formula containing 17 μg Se/L in infants with low selenium status at birth is sufficient to cause a rise to 80% of adult levels at 3 months of age. 相似文献
Methodology Forty-four newborn infants, whose mothers wished to formula feed, were randomized in an open controlled trial to be fed a commercially available selenium supplemented cows milk formula (containing 17 μg Se/L) or an unsupplemented formula (containing 4.6 μg Se/L). Cord, 1 and 3 month blood samples were obtained for selenium status (plasma and red cell selenium and glutathione peroxidase) and thyroid function.
Results Mean plasma selenium and glutathione peroxidase values were significantly higher in supplemented than unsupplemented infants at 1 month (unpaired t -tests; P <0.0001 and P = 0.001 respectively) and 3 months ( P <0.0001 and P = 0.0005). Analysis within treatment groups between time points (paired t -tests) showed that selenium supplementation prevented the fall in plasma selenium from birth to 1 month seen in unsupplemented infants and was associated with a rise in levels between 1 and 3 months ( P = 0.002).
Conclusions Supplementing cows milk formula with selenium to replicate the levels found in breast milk is nutritionally sound. Feeding from a few days of age with a formula containing 17 μg Se/L in infants with low selenium status at birth is sufficient to cause a rise to 80% of adult levels at 3 months of age. 相似文献
42.
Indomethacin-induced mitochondrial dysfunction and oxidative stress in villus enterocytes 总被引:6,自引:0,他引:6
Nonsteroidal anti-inflammatory drugs (NSAIDs) are known to cause small intestinal damage but the pathogenesis of this toxicity is not well established. Intestinal epithelial cells are thought to be affected by these drugs in the course of their absorption. These cells are of different types, viz. villus, middle and crypt cells. There is little information on which of these cells, if any, are particularly vulnerable to the effects of NSAIDs. This paper aimed to study the effects of indomethacin, an NSAID commonly used in toxicity studies, on different populations of enterocytes. Effects of the drug were assessed in terms of oxidative damage, mitotic activity, mitochondrial function and lipid composition in enterocytes isolated from the small intestine of rats that had been orally administered indomethacin. In addition, the effects of arginine and zinc in protecting against such changes were assessed. Cell viability, tetrazolium dye (MTT) reduction and oxygen uptake were significantly reduced in villus tip cells from rats dosed with the drug. Thymidine uptake was higher in the crypt cell fraction from these rats. Similarly, products of lipid peroxidation were elevated in the villus tip cells with a corresponding decrease in the level of the anti-oxidant, alpha-tocopherol. In isolated mitochondrial preparations from various enterocyte fractions, significant functional impairment and altered lipid composition were seen mainly in mitochondria from villus cells. Arginine and zinc pre-treatment were found to protect against these effects. These results suggest for the first time that the villus tip cells are more vulnerable to the damaging effects of indomethacin and that oxidative stress is possibly involved in this damage. 相似文献
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BACKGROUND/PURPOSE: Children with cyanotic congenital heart disease (CCHD) may require laparoscopic procedures. There are no data on the ability of capnography to predict arterial carbon dioxide concentrations (PaCO2) in patients with CCHD during pneumoperitoneum. METHODS: Seven patients (age 1 to 35 months) with CCHD undergoing laparoscopic Nissen fundoplication are presented. Standard general endotracheal anesthesia was administered. The operations were performed either by or in consultation with the cardiac anesthesia team. During each case, concomitant PaCO2 and end-tidal carbon dioxide (ETCO2) measurements were made via an arterial line and capnograph before and after insufflation of the abdomen. The PaCO2-ETCO2 gradients before and during pneumoperitoneum were then compared using a paired Student's t test. RESULTS: There was a statistically significant increase in the PaCO2-ETCO2 gradient (5.7 v 13.4) after insufflation compared with baseline (P <.015). CONCLUSIONS: These preliminary results show that ETCO2 is not a reliable monitor of PaCO2 in patients with CCHD undergoing laparoscopic procedures. The authors feel that close monitoring, including arterial blood gas measurements, and an experienced anesthesia team are necessary to perform laparoscopic procedures in patients with CCHD. 相似文献
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Mark J Schreiber Swee Hoe Ong Richard C G Holland Martin L Hibberd Subhash G Vasudevan Wayne P Mitchell Edward C Holmes 《Infection, genetics and evolution》2007,7(4):540-541
DengueInfo (http://www.dengueinfo.org) is a web portal and database that brings clarity to dengue research by integrating the growing number of complete genome sequences of dengue virus with relevant literature and curated epidemiological information. Additionally, it represents a repository of on-going prospective and retrospective studies of dengue disease severity. We intend the database to be a flagship resource for the dengue community, providing standardized and high quality information and facilitating research into key aspects of dengue biology and assisting in its control. To aid this process we also introduce a standard nomenclature for dengue isolates inspired by globally accepted system used for influenza virus. 相似文献
50.
A retrospective study was conducted in the Pediatric Intensive Care Unit (PICU) of a tertiary care hospital in northern India to profile neonatal admissions and to assess the validity of the Score for Neonatal Acute Physiology (SNAP) in predicting the outcome in terms of mortality and length of hospital stay (LOS). Neonatal sepsis (51%) and birth asphyxia (11.2%) were the commonest indications for admission. Thirty-seven (38.1%) of the neonates died. The mean SNAP score in babies who died was 18.8 +/- 9.8 and 10.1 +/- 6.4 in survivors (P<0.001). There was no correlation between SNAP score and mean length of stay in hospital (P=0.5). We conclude that SNAP correlates well with mortality in neonates admitted to the PICU. 相似文献