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PURPOSE: Epstein-Barr virus (EBV) in Hodgkin's lymphoma (HL) cells has been considered as a prognostic marker for this heterogeneous disease, but studies have yielded mixed findings, likely because of selected patient series and failure to acknowledge an effect of age on outcome. This study assessed survival after HL in a population-based cohort large enough to examine the joint effects of EBV with other factors including age, sex, and histologic subtype. PATIENTS AND METHODS: Included were 922 patients with classical HL diagnosed between mid-1988 and 1997 in the Greater San Francisco Bay Area, with archived biopsy specimens assayed for EBV with immunohistochemistry and in situ hybridization. Vital status was followed through December 30, 2003 (median follow-up time, 97 months). Overall and disease-specific survival were analyzed with the Kaplan-Meier method and Cox proportional hazards regression models. RESULTS: In children less than 15 years old, EBV presence was suggestively associated (P = .07) with favorable survival. In adults aged 15 to 44 years, EBV did not affect HL outcome, although a protective effect was suggested. In older adults (45 to 96 years), EBV presence nearly doubled the risk of overall and HL-specific mortality but only for patients with nodular sclerosis (NS) histologic subtype (hazard ratio for death = 2.5; 95% CI, 1.5 to 4.3). CONCLUSION: In HL, EBV tumor cell presence is associated with better survival in young patients and poorer survival in older patients with NS, independent of other factors. Variation in outcome by age and histology could indicate biologically distinct disease entities. Evidence that EBV is a meaningful prognostic marker may have therapeutic relevance.  相似文献   
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BackgroundLong‐term follow‐up is necessary to understand the impact of perinatal interventions. Exploring parents'' motives and experiences in consenting to their children taking part in longitudinal studies and understanding what outcomes are important to families may enhance participation and mitigate the loss to follow‐up. As existing evidence is largely based on investigators'' perspectives using Western samples, the present pilot study explored parents'' perspectives in a multicultural New Zealand context.MethodsData were generated using semi‐structured interviews with parents whose children had participated in a longitudinal study after neonatal recruitment. Parents'' experiences of being part of the study were analysed thematically using an inductive approach.ResultsParents (n = 16) were generally happy with the outcomes measured. Additionally, parents were interested in lifelong goals such as the impact of parental diabetes. We identified three themes: (1) Facilitators: Research participation was aided by motives and parent and research characteristics such as wishing to help others and straightforward recruitment; (2) Barriers: A hesitancy to participate was due to technical and clinical research aspects, participation burden and cultural barriers, such as complex wording, time commitment and nonindigenous research and (3) Benefits: Children and parents experienced advantages such as the opportunity for education.ConclusionsParents reported positive experiences and described the unexpected benefit of increasing families'' health knowledge through participation. Improvements for current follow‐up studies were identified. Different ethnicities reported different experiences and perspectives, which warrants ongoing research, particularly with indigenous research participants.Patient or Public ContributionNo active partnership with parents of patients took place.  相似文献   
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Background

We report measurements of the temporal response of serum vasopressin concentrations in the period after reperfusion of the liver graft during orthotopic liver transplantation (OLT).

Methods

Vasopressin concentrations were determined in 11 adult patients undergoing OLT by radioimmunoassay of samples collected after induction, at 5 minutes prior to reperfusion, and at 10, 20, 30, 40, 50, 60, 90, and 120 minutes after reperfusion.

Results

Pre-incision vasopressin concentrations ranged from <0.5 to 2.6 pg/mL (reference serum vasopressin, <1.7 pg/mL). Overall, levels increased before reperfusion, but fell thereafter. Individual patients manifested elevated levels during the period after reperfusion. Values immediately before reperfusion exhibited most variability, ranging from 0.8 to 40 pg/mL (median, 15; interquartile range [IQR], 4-29) Median vasopressin concentrations 10 minutes postreperfusion were 7.6 pg/mL (IQR, 3-27). Only 3 of the 11 patients failed to generate vasopressin levels >20 pg/mL. In each of these patients, hemodynamics were satisfactory without the need for additional pressor infusion. Maximum vasopressin concentration measured in any patient was 85 pg/mL. There was no correlation between vasopressin concentration and mean blood pressure or systemic vascular resistance index.

Conclusion

Vasopressin concentrations during OLT vary widely and are elevated periodically during the anhepatic and postreperfusion stages, with no apparent relationship between vasopressin concentrations and blood pressure. Although vasopressin concentrations were not as high as those measured during some other clinical situations, these data suggest that a relative vasopressin deficiency is not a direct cause of hypotension during OLT.  相似文献   
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Opinion statement Providing adequate sedation in the neurologic intensive care unit (ICU) depends on determination of proper goals for sedation, adequate assessment of the level of sedation, and appropriate choice of drug based on the patient’s physiology. The management of sedation in the ICU will influence long-term outcome. Delirium, anxiety, and pain must be identified and treated separately. The use of protocols can improve compliance with published evidence-based recommendations. Propofol and dexmedetomidine may be used for rapidly titratable sedation, benzodiazepines for anxiolysis, neuroleptics for treatment of delirium, and opiates for analgesia. Unique aspects of patients with acute brain disease, such as elevated intracranial pressure or status epilepticus, require adaptation of sedative regimens. Processed EEG monitoring and volatile anesthetic agents have not yet proven beneficial or practical for use in the ICU.  相似文献   
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Risk factors for foot fracture among individuals aged 45 years and older   总被引:2,自引:0,他引:2  
A case-control study undertaken among members of five Northern California Kaiser Permanente medical centers sought to identify risk factors for foot fractures among persons aged 45 years and older. Foot fracture cases (n=920) and frequency matched controls (n=2366) were interviewed between October 1996 and May 2001 using a standardized questionnaire. Foot fractures occurred most often while walking or climbing stairs. While 60% of foot fractures resulted from falls, 20% were attributed to other causes, such as hitting the foot or tripping on sidewalks and curbs. Having a self-reported history of physician-diagnosed diabetes [adjusted odds ratio (OR)=1.45, 95% confidence interval (CI)=1.10–1.91] or cataracts (OR=1.40, 95% CI=1.07–1.83), having a self-reported foot problem (OR=1.38, 95% CI=1.06–1.78 for two or more foot problem versus no foot problems), having difficulty walking in minimum light (OR=1.86, 95% CI=1.14–3.05) and having had a prior fracture (OR=1.20, 95% CI=1.05–1.37) were associated with increased risk. Putative protective factors for osteoporotic fractures, such as menopausal hormone therapy use, thiazide or water pill use, high calcium intake, and high body mass index were not associated with foot fracture risk. These findings suggest that risk factors for foot fractures among older people differ in part from risk factors for other fracture sites generally considered to be osteoporotic, such as the hip, vertebrae, and forearm.  相似文献   
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