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71.
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It is widely believed that the improved survival of young people with chronic diseases will be associated with the development of appropriate services within the adult healthcare domain. There is, however, little evidence to suggest that this is happening at a rate commensurate with clinical requirements. This paper highlights the multiplicity of barriers that impede the development of transition services to facilitate the transfer of medical care from the paediatric to the adult domain. Different models of transition care are described, and the terms 'transfer' and 'transition' are differentiated. The clinical demand for service development is highlighted, as well as the need for specific research in this area of healthcare delivery. 相似文献
73.
Guest AR Helvie MA Chan HP Hadjiiski LM Bailey JE Roubidoux MA 《AJR. American journal of roentgenology》2000,175(3):805-810
OBJECTIVE: The purpose of our study was to show that compressed breast thickness on mammograms in overweight and obese women exceeds the thickness in normal-weight women and that increased thickness results in image degradation. SUBJECTS AND METHODS: Three hundred consecutive routine mammograms were reviewed. Patients were categorized according to body mass index. Compression thickness, compressive force, kilovoltage, and milliampere-seconds were recorded. Geometric unsharpness and contrast degradation were calculated for each body mass index category. RESULTS: Body mass index categories were lean (3%), normal (36%), overweight (36%), and obese (25%). Body mass index was directly correlated with compressed thickness. In the mediolateral oblique view, the mean thickness of the obese category exceeded normal thickness by 18 mm (p < 0.01), corresponding to a 32% increase in geometric unsharpness. Mean obese thickness exceeded lean thickness by 33 mm (p < 0.01), corresponding to a 79% increase in unsharpness. Similar trends were observed for the craniocaudal view. In the mediolateral oblique projection, there was an increase of 1.0 kVp (p < 0.01) for obese compared with normal and 1.7 kVp (p < 0.01) between lean and obese, corresponding, respectively, to a 16% and a 25% decrease in image contrast because of scatter and kilovoltage changes. Milliampere-seconds increased by 47% on the mediolateral oblique images in the obese category compared with normal body mass index. CONCLUSION: An increased body mass index was associated with greater compressed breast thickness, resulting in increased geometric unsharpness, decreased image contrast, and greater potential for motion unsharpness. 相似文献
74.
Mariani J Ou R Bailey M Rowland M Nagley P Rosenfeldt F Pepe S 《The Journal of thoracic and cardiovascular surgery》2000,120(4):660-667
BACKGROUND: Recovery of cardiac function after cardiac surgery and other interventional cardiac procedures in elderly patients is inferior to that in younger patients, suggesting that the aged myocardium is more sensitive to ischemia and other stresses. Although convincing data from animal studies of senescence now exist, there is a dearth of controlled in vitro studies that examine the specific response of aged human myocardium to the stress of hypoxia or ischemia. OBJECTIVE: We sought to determine the effect of age on the capacity of human atrial trabeculae to recover contractile function after in vitro hypoxic or ischemic stress. METHODS: Atrial pectinate trabeculae were dissected from the tip of 58 right atrial appendages harvested during an operation in patients aged between 34 and 89 years and electrically stimulated at 1 Hz in oxygenated Ringer's solution at 37 degrees C. Tissues experienced 30 minutes of either hypoxia (N(2) and perfusate) or simulated ischemia (humidified N(2) without perfusate) and were returned to normoxia for recovery of function for 30 minutes. Developed force and other contractile variables were determined during each period. RESULTS: Under normoxic conditions, no significant age difference was observed for any contractile function variable. However, after hypoxia, the old (70-89 years) and intermediate age groups (60-69 years) showed reduced recovery of developed force (48.5% +/- 22.2% [n = 11] and 44.9% +/- 19% [n = 12], respectively) compared with that found (66.4% +/- 19.7% [n = 15]) in the younger (34-59 years) group (mean +/- SD, P =.02). Similarly, after simulated ischemia, the groups of 70- to 89-year-old and 60- to 69-year-old subjects showed reduced recovery of developed force (35.7% +/- 17% [n = 5] and 51.1% +/- 11.8% [n = 9], respectively) compared with that found (68.2% +/- 10.4% [n = 6]) in the group of 34- to 59-year-old subjects (P =.01). Multivariable analysis, comparing 20 factors of surgical patient characteristics and recovery of developed force, found that only age (P =.01) and hypertension (P =.01) were predictors of reduced recovery of developed force after either hypoxia or simulated ischemia. CONCLUSIONS: In aged human atrial myocardium, the capacity to recover contractile function after in vitro hypoxia or simulated ischemia is reduced compared with the younger myocardium of mature adults. These findings suggest that enhanced myocardial protective strategies may be indicated for elderly patients undergoing cardiac surgery. 相似文献
75.
Our understanding of the actions of extracellular ATP in controlling kidney function via stimulation of P2 receptors is still at an early stage. Recently, several groups, including our own, have begun to address this subject: in this brief review, we discuss some of these effects and speculate on likely function of extracellular nucleotides in the kidney. 相似文献
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Joe E.Acker Ⅲ Todd J.Crocco Marc K.Eckstein Edward C.Jauch Neil M.Meltzer John W.Munn Charles Sand Jeffrey L.Saver Brian Eigel Brian R.Gilpin Mark Schoeberl Penelope Solis Katie B.Hortort 曹勇军 李瑞霞 刘芳 刘春风 《国际脑血管病杂志》2008,16(7):481-498
尽管卒中的预防、诊断、治疗和康复已取得一些进展,但卒中在美国仍然是第三大死亡原因和长期残疾的主要原因.每年约有70万人新发或复发卒中[1].在过去10年里,急性卒中诊治的一些进展,包括纤溶和其他短期疗法的引入,突出显示了急诊医疗服务(emergency medical services,EMS)机构和急诊医疗服务体系(emergency medical services systems,EMSS)在优化卒中医疗中的关键作用[2-7]. 相似文献
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The efficacy of thickened feedings for the treatment of gastroesophageal reflux in infancy was evaluated. Fifty-two infants were examined with prolonged pH monitoring of the distal esophagus after feedings of apple juice or apple juice thickened with rice cereal. All infants had a minimum of three feedings of both thickened and unthickened juice. The recordings of distal esophageal pH were analyzed for the percent of time the pH was less than 4 in the first 2 hours after each feeding. The infants were maintained in the following positions after feeding: prone (n = 29), prone-board with the head elevated 30 degrees from horizontal (n = 29), supine (n = 7), and unrestricted (n = 21). We found no significant difference in the percent of time with reflux with thickened versus unthickened feedings except in those infants maintained in the 30-degree prone position. In the first 2 hours after eating thickened juice, infants maintained in this position had increased esophageal reflux time (P less than 0.006). Further analysis revealed that 33% of the infants had a greater than 30% increase in esophageal reflux time after thickened feedings. Our study suggests that the immediate effect of thickened feedings on gastroesophageal reflux in infants is unpredictable. 相似文献