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1.
Background. The National Heart, Lung, and Blood Institute (NHLBI) guidelines recommend that patients receive a follow-up outpatient asthma visit after being discharged from an emergency department (ED) for asthma. Objective. To measure the frequency of follow-up outpatient asthma visits and its association with repeat ED asthma visit. Design. We conducted a retrospective cohort study of children with asthma using claims data from a university-based managed care organization from 01 1998 to 10 2000. We performed a multivariate survival analysis using Cox proportional hazards model to determine the effect of follow-up outpatient asthma visits on the likelihood of a repeat ED asthma visit, after controlling for severity of illness, patient age, gender, insurance, and the specialty of the primary care provider. Results: A total of 561 children had 780 ED asthma visits. Of these, 103 (17%) had a repeat ED asthma visit within 1 year. Almost two-thirds of children (66%) did not receive outpatient follow-up for asthma within 30 days of an ED asthma visit. Outpatient asthma visits within 30 days of an ED asthma visit are associated with an increased likelihood (relative risk = 1.80; 95% confidence interval 1.19, 2.72) for repeat ED asthma visits within 1 year. Conclusions. Most patients do not have outpatient follow-up after an ED asthma visit. However, those patients that present for outpatient follow-up have an increased likelihood for repeat ED asthma visits. For the primary care provider, these outpatient follow-up visits signal an increased risk that a patient will return to the ED for asthma and are a key opportunity to prevent future ED asthma visits.  相似文献   
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目的 探讨创伤后迟发性脑肿胀的临床特点、发病机制与治疗。方法 回顾性分析1998年1月~2005年6月年收治的17例迟发性脑肿胀患者的临床特点和救治情况。结果 所有颅脑损伤患者采用保守治疗后均有好转,但于伤后5-10d出现恶化,CT复查有脑肿胀,经加强综合脱水等治疗后16例治愈,1例死亡。结论 迟发性脑肿胀好发于对冲性额、颞叶挫裂伤伴明显蛛网膜下腔出血、硬膜下薄层血肿及早期CT有脑肿胀者。其发病机制可能与创伤后的迟发性脑血管痉挛、微循环障碍、静脉回流障碍及甘露醇作用下降等因素有关。此类患者病情隐蔽性强,应加强观察、积极行CT复查,如能早期明确诊断,保守治疗多数效果良好。  相似文献   
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Retrorenal colon: implications for percutaneous diskectomy   总被引:1,自引:0,他引:1  
Helms  CA; Munk  PL; Witt  WS; Davis  GW; Morris  J; Onik  G 《Radiology》1989,171(3):864-865
It has been recommended that computed tomography (CT) with the patient prone be performed in every patient undergoing percutaneous diskectomy; this would enable detection of a retrorenal location of the colon, which could interfere with the percutaneous procedure. In this evaluation of 346 prone CT studies, only one patient (0.29%) was found to have retrorenal or retropsoas bowel that would have been perforated at diskectomy. Because of this extremely low prevalence, the performance of prone CT in every patient undergoing percutaneous lumbar diskectomy is not believed to be necessary.  相似文献   
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BACKGROUND: In a previous investigation we reported on magnetic forces in the static magnetic field of a 1.5 Tesla MRI system. The aim of the present investigation was to assess forces on orthodontic wires in a high field strength MRI system at 3 Tesla. MATERIALS AND METHODS: Thirty-two different orthodontic wires (21 archwires, eight ligature wires and three retainer wires) were investigated in a 3 Tesla high field strength MRI system (Intera, Philips Medical Systems, Best, The Netherlands). Translational forces were measured by the deflection angle test (ASTM F2052-02), and rotational forces assessed on a 5-point qualitative scale. RESULTS AND CONCLUSION: Translational forces ranged between 43.5 mN and 136.1 mN for retainer wires and between 0.6 mN (Noninium) and 208.4 mN (Orthos Stainless Steel) for steel archwires. Translational forces were up to 53.8 times as high as gravitational forces for retainer wires and up to 54.5 times as high for steel archwires, associated with marked rotational forces for the most part. Archwires manufactured from nickel-titanium, titanium-molybdenum and cobalt-chromium and different ligature wires showed no or negligible forces in the magnetic field. Carefully ligated wires should not present a risk due to translational and rotational forces in the high field MRI system at 3 Tesla.  相似文献   
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采用间接ELISA检测23名肾移植受者血清巨细胞病毒(CMV)抗体,共检出18名(78%)活动性CMV感染,其中10名(44%)为原发性感染。结果证实CMV-IgE和-IgA具有较好的血清学诊断价值,优于CMV-IgM。  相似文献   
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The beta-amyloid (Abeta) precursor protein (APP) is cleaved sequentially by beta-site of APP-cleaving enzyme (BACE) and gamma-secretase to release the Abeta peptides that accumulate in plaques in Alzheimer's disease (AD). GGA1, a member of the Golgi-localized gamma-ear-containing ARF-binding (GGA) protein family, interacts with BACE and influences its subcellular distribution. We now report that overexpression of GGA1 in cells increased the APP C-terminal fragment resulting from beta-cleavage but surprisingly reduced Abeta. GGA1 confined APP to the Golgi, in which fluorescence resonance energy transfer analyses suggest that the proteins come into close proximity. GGA1 blunted only APP but not notch intracellular domain release. These results suggest that GGA1 prevented APP beta-cleavage products from becoming substrates for gamma-secretase. Direct binding of GGA1 to BACE was not required for these effects, but the integrity of the GAT (GGA1 and TOM) domain of GGA1 was. GGA1 may act as a specific spatial switch influencing APP trafficking and processing, so that APP-GGA1 interactions may have pathophysiological relevance in AD.  相似文献   
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