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21.
Previous studies have demonstrated an increase in a low molecular weight angiogenic factor (ESAF) present in the retinae of kittens with oxygen induced retinopathy. The present paper describes differences in the quantity of ESAF extracted from the vitreous humour of control and oxygen treated animals and proposes a mechanism for the induction of intravitreal neovascularisation.  相似文献   
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Free vascularized fibular bone grafts were used in nineteen children, seen consecutively, who had congenital pseudarthrosis of the tibia. The average age was 5.1 years (range, 1.4 to 11.4 years). Sixteen of the patients had been treated with electrical stimulation for at least one year, and the tibia had not united. All but four patients had had at least one previous operative procedure. At an average follow-up of 6.3 years (range, 2.0 to 11.0 years), eighteen (95 per cent) of the nineteen pseudarthroses had healed. The leg-length discrepancy averaged 1.6 centimeters (range, 0 to 4.0 centimeters), but ten tibiae had residual or progressive valgus or anteroposterior malalignment despite bracing. There was minimum morbidity at the donor site.  相似文献   
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OBJECTIVE: Surgery for Crohn's disease (CD) is associated with a high recurrence rate and quality of life (QOL) in these patients is controversial. The aim of this study was to assess QOL in patients after laparoscopic and open surgery for CD by two different validated instruments, a generic nonspecific score and a specific gastrointestinal QOL index. PATIENTS AND METHODS: Patients with CD who underwent elective laparoscopic or open ileocaecal resection with primary anastomosis between 1992 and 2000 were followed for recurrence and surgery-related complications. QOL was assessed by the SF-36 Health Survey containing a mental (MCS) and a physical (PCS) component summary score and by the Gastrointestinal Quality of Life Index (GIQLI) developed by Eypasch. RESULTS: Thirty-seven patients with a mean age of 48.8 +/- 18.4 years including 23 females and 14 males were evaluated at a mean follow-up of 42.6 +/-25.8 months (minimum of 8 months). Twenty-one (57%) patients underwent laparoscopic resection and 16 (43%) open surgery. Both groups were well matched for age, gender, ASA class and body mass index. Fourteen (38%) patients developed recurrent disease and 3 (8%) had postoperative incisional hernias. Overall, QOL scores were 103 +/- 26.8 for the GIQLI, 47.2 +/- 11.8 for the PCS, and 49.2 +/- 11.5 for the MCS. The GIQLI correlated well with the SF36, correlation coefficient = 0.68 for GIQLI vs PCS (95% CI, 0.41,0.95) and 0.67 for GIQLI vs MCS (95%CI, 0.39, 0.95), respectively. When compared to the general US population, mean GIQLI scores (-13.8, P = 0.002) and mean PCS scores (-4.7, P = 0.001) were significantly lower in these patients than in healthy individuals. In a multivariate analysis of impact factors on QOL, recurrence within the follow-up period was the single significant determinant reducing the PCS (-35.1, P = 0.026) and the GIQLI (-36.1, P = 0.018). CONCLUSION: QOL is significantly reduced in patients with CD at long-term follow-up after both laparoscopic and open surgery. Recurrence is the only factor adversely affecting QOL of CD patients in remission irrespective of the operative technique applied.  相似文献   
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Early intervention with budesonide is an effective strategy for mild persistent asthma, which has been shown to provide additional clinical benefits at a low incremental cost using USA cost data. The present authors analysed whether this strategy would be cost-effective using cost data for other countries. Based on the 3-yr prospective, randomised, double-blind inhaled Steroid Treatment As Regular Therapy (START) in early asthma study (comparing budesonide and placebo combined with usual asthma therapy), the cost-effectiveness was estimated separately for eight different countries, from both healthcare payer and societal perspectives, of adding budesonide to usual asthma therapy. Local unit costs were applied to data for the total trial population. Incremental cost-effectiveness ratios (ICER) were estimated as cost per symptom-free day (SFD) gained. Budesonide increased SFDs by an average of 14.1 days annually. From a healthcare payer perspective, budesonide would reduce the total cost of asthma care in Australia. In Sweden, Canada, France, Spain, UK, China and the USA, the ICER ranged from US$2.4-11.3 per SFD. From a societal perspective, budesonide would be cost-saving in Australia, Canada and Sweden. In conclusion, for countries where costs with budesonide are higher, the policy implication has to be determined by that health system's willingness to pay for an additional symptom-free day. However, where budesonide therapy increases symptom-free days and reduces total costs, the policy conclusion clearly favours early intervention.  相似文献   
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The insulin receptor substrate-2/phosphoinositide 3-kinase (PI3K) pathway plays a critical role in the regulation of β-cell mass and function, demonstrated both in vitro and in vivo . The serine threonine kinase Akt is one of the promising downstream molecules of this pathway that has been identified as a potential target to regulate function and induce proliferation and survival of β cells. Here we summarize some of the molecular mechanisms, downstream signalling pathways and critical components involved in the regulation of β-cell mass and function by Akt.  相似文献   
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