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OBJECTIVE: To identify the clinical utility of obtaining blood, urine and cerebrospinal fluid for bacterial culture among febrile infants <90 days of age with clinical bronchiolitis. DESIGN: Retrospective chart review from 1995 to 2000. SETTING: Urban emergency department of a tertiary children's hospital. PARTICIPANTS: All infants <90 days of age presenting with fever and clinical bronchiolitis. MAIN OUTCOME MEASURES: Result of the cultures of blood, urine and cerebrospinal fluid. RESULTS: Of 3051 (11%) febrile infants, 329 met criteria for clinical bronchiolitis. Blood for culture was obtained from 309 (94%), urine for culture was obtained from 273 (83%) and cerebrospinal fluid for culture was obtained from 200 (61%). One hundred eighty-seven (57%) infants had all 3 specimens sent for culture. No cases of bacteremia [0%; 95% confidence interval (CI), 0, 1.1%] or meningitis (0%; 95% CI 0, 1.8%) occurred among these infants. However, 6 infants (2%; 95% CI 0.8, 5.7%), all male, had a culture of urine consistent with infection (4 Escherichia coli, 1 Staphylococcus aureus, 1 viridans streptococci). CONCLUSION: The risk of bacteremia or meningitis among infants <90 days with fever and bronchiolitis is low in this age group. The risk of urinary tract infection in this age group is also low, but not negligible, at 2%. 相似文献
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Studies from many laboratories have shown that overexpression of manganese superoxide dismutase (MnSOD) inhibits the growth of numerous tumor cell types. The inhibition of tumor cell growth can be attributed to the increase in the steady-state levels of H2O2 as a result of the increased dismuting activity of MnSOD. Here we demonstrate that overexpression of MnSOD enhances the activity of the superoxide (O2*-)-sensitive enzyme aconitase, decreases the intracellular GSH/GSSG ratio, and dose-dependently inhibits pyruvate carboxylase activity. Thus, alterations in the steady-state concentrations of mitochondrial O2*- and H2O2 as a result of MnSOD overexpression can alter the metabolic capacity of the cell leading to inhibition of cell growth. Furthermore, we propose that MnSOD overexpression can modulate the activity of nitric oxide (*NO) by preventing its reaction with O2*-. This hypothesis suggests that the redox environment of the mitochondria can be altered to favor the activity of *NO rather than peroxynitrite (ONOO-) and may explain the enhanced toxicity of *NO-generating compounds toward MnSOD-overexpressing cell lines. These findings indicate that therapeutic strategies targeted at overexpressing MnSOD in tumor tissue may be more effective when used in combination with agents that deplete the oxidant-buffering and enhance the *NO-generating capacity of the tumor and host, respectively. 相似文献
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Comparison of the human and mouse genes encoding the telomeric protein, TRF1: chromosomal localization, expression and conserved protein domains 总被引:11,自引:0,他引:11
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Roderik Metz Gino MMJ Kerkhoffs Egbert-Jan MM Verleisdonk Geert J van der Heijden 《BMC musculoskeletal disorders》2007,8(1):108
Background
We present the design of an open randomized multi-centre study on surgical versus conservative treatment of acute Achilles tendon ruptures. The study is designed to evaluate the effectiveness of conservative treatment in reducing complications when treating acute Achilles tendon rupture. 相似文献100.
PR Kamudoni K Maleta Z Shi MM De Paoli G Holmboe‐Ottesen 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(3):367-372
Aim: To investigate mothers’ perceptions of breastfeeding and influences from their social network. Methods: A cross‐sectional survey was carried out in Mangochi district, Malawi where questionnaire data from 157 rural and 192 semi‐urban mother–infant pairs were obtained. Results: The proportion of mothers who thought that exclusive breastfeeding should last for 6 months and those who reported to have actually exclusively breastfed were 40.1% and 7.5% respectively. Of those who reported practising exclusive breastfeeding for 6 months, 77.5% stated that exclusive breastfeeding should last for 6 months. This opinion was independently associated with giving birth in a Baby‐Friendly facility, OR = 5.22; 95% CI (1.92–14.16). Among the mothers who thought that exclusive breastfeeding should last for less than 6 months, 43.9% reported having been influenced in their opinion by health workers. Infant crying was the most common (62.4%) reason for stopping exclusive breastfeeding. Conclusion: The findings illustrate the positive impact health workers can have, as well as the need to raise awareness of the benefits of exclusive breastfeeding among both health workers and mothers. Furthermore, continued counselling of mothers on how to deal with stressful infant behaviour such as crying may assist to prolong exclusive breastfeeding. 相似文献