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41.
At birth, the mammalian nervous system must adapt rapidly to the new conditions it encounters in the extra-uterine environment. One aspect of this adaptation, known as arousal, is mediated by catecholamines, the levels of which in the brain increase rapidly after birth. The pattern of gene expression also changes. Shortly after birth, expression of the immediate early gene c-fos, known to reflect general neural activity, is up-regulated. Furthermore, asphyxia often occurs in connection with birth. In order to examine the effects of this phenomenon on the expression of c-fos, as well as on the rate of noradrenaline (NA) turnover, asphyxia was induced in rat pups delivered by caesarean section. Northern blot analysis and in situ hybridization revealed that the increase in expression of c-fos in certain areas of the brain was greatly enhanced by asphyxia of moderate duration; whereas more prolonged asphyxia lowered the level of c-fos mRNA. Asphyxia had a similar effect on the rate of NA turnover. Adrenergic receptor antagonists administered prior to birth attenuated the birth-related induction of c-fos mRNA. However, the potentiation of c-fos expression by asphyxia was not altered by these antagonists. Therefore, we propose that while catecholamines play an important role in the induction of c-fos in the brain at birth, the effects of asphyxia involve a different mechanism. 相似文献
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Jean-Michel Liet Soizic Paranon Louis Baraton Jean-Marc Dejode Jean-Christophe Rozé 《Pediatric critical care medicine》2006,7(6):541-544
OBJECTIVE: An adult trial reported the efficacy of recombinant human erythropoietin in critically ill patients with a 19% decrease in red blood cell transfusion. Our aim was to evaluate the relevance of this prophylactic treatment in children hospitalized in a pediatric intensive care unit (PICU). DESIGN: Cohort study from January 1995 to December 2004. SETTING: University hospital PICU. PATIENTS: Children between 1 month and 18 yrs of age. INTERVENTIONS: We searched through a prospective databank for all children hospitalized in the PICU for > or =4 days (potential recipients of erythropoietin, as proposed in the adult trial) and transfused with red blood cells after day 7 following PICU entry (in whom erythropoietin might prevent anemia, according to results of the adult trial). MEASUREMENTS AND MAIN RESULTS: We found that 799 of 2,578 children (31%) were hospitalized for > or =4 days. The study group comprised 787 patients who were hospitalized for > or =4 days in the PICU and for whom full records were available. One hundred eighty-three children in this study group were transfused during their stay in the PICU (median age, 7 months; weight, 6.60 kg). Hemoglobin levels before transfusion (mean +/- sd) were 7.7 +/- 1.5 g/dL. These transfused children represented 23% of the study group and 7% of the total PICU admissions. Forty-seven children (6% of the study group, 2% of the total PICU admissions) were transfused with red blood cells after 7 days of hospitalization and could have benefited from a prophylactic treatment with erythropoietin. Relative risk to benefit of a prophylactic treatment by erythropoietin was higher in cases of mechanical ventilation (relative risk, 1.18) and inotropic treatment (relative risk, 1.72) and if the main diagnosis involved dermatological (relative risk, 3.03) or oncologic disease (relative risk, 3.94). CONCLUSIONS: If we applied the results of the adult trial to our PICU, we would have to treat 31% of the children with prophylactic erythropoietin and thereby expect a reduction of one red blood cell transfusion for every 17 treated patients. 相似文献
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Asma Sassi Lotfi Loucif Sushim Kumar Gupta Mazouz Dekhil Houria Chettibi Jean-Marc Rolain 《Antimicrobial agents and chemotherapy》2014,58(9):5606-5608
Here, we report the first autochthonous cases of infections caused by blaNDM-5 New Delhi metallo-β-lactamase-producing Escherichia coli strains recovered from urine and blood specimens of three patients from Algeria between January 2012 and February 2013. The three isolates belong to sequence type 2659 and they coexpress blaCTX-M-15 with the blaTEM-1 and blaaadA2 genes. 相似文献
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A relative immunosuppression is observed in patients after sepsis, trauma, burns, or any severe insults. It is currently proposed that selected patients will benefit from treatment aimed at boosting their immune systems. However, the host immune response needs to be considered in context with pathogen-type, timing, and mainly tissue specificity. Indeed, the immune status of leukocytes is not universally decreased and their activated status in tissues contributes to organ failure. Accordingly, any new immune-stimulatory therapeutic intervention should take into consideration potentially deleterious effects in some situations. 相似文献
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H Chappuy P Taupin J Dimet YE Claessens JM Tréluyer G Chéron;the GFRUP 《Acta paediatrica (Oslo, Norway : 1992)》2012,101(10):1089-1094
Aim: We evaluated the extent to which parents understood the medical information about hospitalization of their child in an emergency department and looked for characteristics likely to increase the risk of poor comprehension. Methods: Prospective multicenter study in thirteen paediatric emergency departments. The parents and doctors completed questionnaires based on closed‐ended questions with a common core of four items: reasons of hospitalization, diagnosis, treatment and seriousness of child condition. We evaluated concordance between parents and doctor answers for these items by comparing their responses. Results: This study included 380 parents. Percentage of concordance was 55% for the reason of hospitalization, 78% for the diagnosis, 92% for the treatment, 48% for the seriousness of the condition and 19% for all four items. The mean number of concordant items was 2.76 (CI 95%, 2.66–2.86). Parents whose children seemed not in pain and parents who received additional information from the nurse showed significantly slightly higher levels of concordance with doctor’s answers (2.98 vs 2.66, p = 0.006 and 2.89 vs 2.60, p = 0.004, respectively). Conclusion: This study shows that improvements are required in the clarity of the information delivered to the parents. The assistance of nurses and optimal pain management may help to improve communication. 相似文献
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