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Background: Volatile anesthetics have protective effects against cytokine-induced injury in endothelial and vascular smooth muscle cells. The authors hypothesized that isoflurane pretreatment may trigger immediate and delayed protection that is modulated by adenosine triphosphate-sensitive potassium channels.

Methods: Human and bovine endothelial cells and rat vascular smooth muscle cells were pretreated with isoflurane (1.5% for 30 min) and then exposed to cytokines (tumor necrosis factor-[alpha], interferon-[gamma], and interleukin-[beta]) for 72 h. Cytokine exposure was initiated immediately after isoflurane pretreatment or after a delay of 1-48 h. Cell survival and viability were evaluated by trypan blue exclusion and lactate dehydrogenase release. The role of mitochondrial and cell membrane adenosine triphosphate-sensitive potassium channels, or both, were evaluated with the antagonists 5-hydroxydecanoate, HMR-1098, or glybenclamide.

Results: Immediate isoflurane pretreatment was approximately 70% effective in increasing cell survival and prevented lactate dehydrogenase release in all cell lines. However, cellular protection was completely lost if the time between isoflurane and cytokine exposure was extended to 2-12 h, depending on the cell type. Delayed protection was equal to immediate protection when the interval was extended to 12-24 h, with protection being sustained at 48 h in human endothelial and rat vascular smooth muscle cells. The immediate and delayed protection was inhibited by glybenclamide and 5-hydroxydecanoate but not by HMR-1098, whereas diazoxide, a mitochondrial adenosine triphosphate-sensitive potassium channels agonist, mimicked the time course of isoflurane-induced immediate and delayed protection in all cell lines.  相似文献   

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OBJECTIVES: To examine ventilatory support for the VLBW infant over the past 10 years in a single academic NICU and determine factors that predicted length of ventilation, death, and CLD. STUDY DESIGN: A retrospective cohort review of neonatal blood gases, ventilatory support, and clinical outcomes. RESULTS: From 1992 through October 2002, 6254 infants were admitted, of whom 2388 required intubation for mechanical ventilation. Of these, 837 were <1500 g at birth (VLBW) infants and 453 were less than 1000 g (ELBW). Total duration of ventilation decreased in all weight groups. Noninvasive ventilatory support increased from 20 to 55% of total ventilation from 1997 to 2002. During this same period, CLD decreased from 20 to 11% in ventilated VLBW infants. Duration of total ventilation was best predicted by birth weight, with each 100 g increment decreasing the duration of ventilation by 71 hours. Lower birth weight, male sex, and a longer total duration of ventilatory support were significant factors in predicting the occurrence of CLD. Death alone was best predicted by lower birth weight and maximum oxygen index (OI). Transported infants had significantly increased maximal OIs, durations of ventilation, and incidence of death. A total of 48% of infants with a single OI >10 either died or survived with CLD. CONCLUSIONS: Birth weight is the best predictor of duration of ventilation, and CLD is best predicted by birth weight, duration of ventilation and male sex. The increasing use of noninvasive strategies has not been associated with an observable increase in respiratory morbidity. VLBW infants with a single OI>10 may benefit from inclusion in future interventional rescue studies.  相似文献   
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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   
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BACKGROUND: The mainstay of treatment for pemphigus is systemic corticosteroids. Different adjuvants have been used to reduce side-effects of long-term corticotherapy. Gold is an anti-inflammatory drug used in autoimmune diseases, whose use has waned with the advent of new immunosuppressive agents. OBJECTIVE: To study the outcome of the use of intramuscular gold treatment of pemphigus vulgaris refractory to previous therapies. METHODS: Thirteen patients with pemphigus vulgaris who had failed to respond to several prior therapies were treated with aurothiomalate, as a steroid-sparing agent. Patients were monitored to assess disease activity and gold toxicity. RESULTS: Seven patients achieved complete remission. Four patients were able to taper prednisone doses, although pemphigus flared when prednisone was discontinued or reduced. Toxicity was observed in the other two patients. CONCLUSIONS: In 53.4% of the patients, the use of chrysotherapy resulted in the complete clearing of the disease, discontinuation of all systemic therapies and induced a long-term clinical remission. Prednisone doses were able to be reduced in the remaining 46.6%. Any side-effects were reversible with drug discontinuation. Gold therapy showed efficacy as a secondary line treatment in refractory pemphigus vulgaris.  相似文献   
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One-hundred and six male children aged 6-23 months with a history of acute watery diarrhoea of less than 72 h duration were randomized to receive either folic acid in a dose of 5 mg at 8-h intervals or placebo for 5 d. There were 54 children in the folic acid group and 52 in the placebo group. The admission characteristics were comparable between the two groups. No significant differences were observed in the intake of oral rehydration solution or stool output between the groups. The mean ± SD of total stool output (g kg−1) was 532 ± 476 vs 479 ± 354 and the duration (h) of diarrhoea was 108 ± 68 vs 103 ± 53 in the folic acid vs placebo group, respectively. The findings, therefore, should have a positive influence on preventing the inappropriate use of folic acid in acute diarrhoea.  相似文献   
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