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Frameworks for deriving occupational exposure limits (OELs) and OEL-analogue values (such as derived-no-effect levels [DNELs]) in various regulatory areas in the EU and at national level in Germany were analysed. Reasons for differences between frameworks and possible means of improving transparency and harmonisation were identified. Differences between assessment factors used for deriving exposure limits proved to be one important reason for diverging numerical values. Distributions for exposure time, interspecies and intraspecies extrapolation were combined by probabilistic methods and compared with default values of assessment factors used in the various OEL frameworks in order to investigate protection levels. In a subchronic inhalation study showing local effects in the respiratory tract, the probability that assessment factors were sufficiently high to protect 99% and 95% of the target population (workers) from adverse effects varied considerably from 9% to 71% and 17% to 87%, respectively, between the frameworks. All steps of the derivation process, including the uncertainty associated with the point of departure (POD), were further analysed with two examples of full probabilistic assessments. It is proposed that benchmark modelling should be the method of choice for deriving PODs and that all OEL frameworks should provide detailed guidance documents and clearly define their protection goals by stating the proportion of the exposed population the OEL aims to cover and the probability with which they intend to provide protection from adverse effects. Harmonisation can be achieved by agreeing on the way to perform the methodological steps for deriving OELs and on common protection goals.  相似文献   
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BackgroundAmerican Society of Clinical Oncology guidelines recommend that patients ≥65 years of age starting chemotherapy undergo a geriatric assessment (GA) to inform and guide management; however, little is known about resources available in community oncology practices to implement these guidelines and to facilitate geriatric oncology research.Materials and MethodsOncology practices within the National Cancer Institute Community Oncology Research Program (NCORP) were electronically surveyed in 2017 regarding the availability of specialty providers, supportive services, and practice characteristics, as part of a larger survey of cancer care delivery research capacity.ResultsOf the 943 NCORP practices, 504 (54%) responded to the survey, representing 210 practice groups. The median new cancer cases per year ≥65 years of age was 457 (interquartile range 227–939). Of respondents, only 2.0% of practices had a fellowship‐trained geriatric oncologist on staff. Geriatricians were available for consultation or comanagement at 37% of sites, and of those, only 13% had availability within the oncology clinic (5% of overall). Practice size of ≥1,000 new adult cancer cases (ages ≥18) per year was associated with higher odds (1.81, confidence interval 1.02–3.23) of geriatrician availability. Other multidisciplinary care professionals that could support GA were variably available onsite: social worker (84%), nurse navigator (81%), pharmacist (77%), dietician (71%), rehabilitative medicine (57%), psychologist (42%), and psychiatrist (37%).ConclusionOnly a third of community oncology practices have access to a geriatrician within their group and only 5% of community sites have access within the oncology clinic. Use of primarily self‐administered GA tools that direct referrals to available services may be an effective implementation strategy for guideline‐based care.Implications for PracticeOnly a minority of community oncology practices in the U.S. have access to geriatric specialty care. Developing models of care that use patient‐reported measures and/or other geriatric screening tools to assess and guide interventions in older adults, rather than geriatric consultations, are likely the most practical methods to improve the care of this vulnerable population.  相似文献   
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Introduction

Coronary vasospasm associated with fluoropyrimidine (FP)-based chemotherapy is a potentially serious complication and reported to occur more often with infusional 5-fluorouracil (5-FU) or capecitabine than with bolus 5-FU. Given the additional benefit of oxaliplatin over FP alone in the management of colorectal cancer, retaining oxaliplatin in the treatment regimen is desirable, but the safety of combining bolus 5-FU with oxaliplatin in patients with FP-induced vasospasm is not well established. We performed a retrospective review to explore the safety of substituting FLOX (bolus 5-FU, oxaliplatin, leucovorin) for FOLFOX (infusional 5-FU, oxaliplatin, leucovorin) and CAPOX (capecitabine, oxaliplatin) in patients who had FP-induced coronary vasospasm.

Patients and Methods

The pharmacy database of Mayo Clinic was queried to identify patients who developed coronary vasospasm associated with FOLFOX or CAPOX between January 2011 and January 2018 and were subsequently treated with FLOX. Detailed information was obtained on these patients by retrospective electronic chart review.

Results

A total of 10 patients (median age, 56.5 years; range, 36-77 years) were identified, 9 with FOLFOX and 1 with CAPOX. Among the patients treated with FOLFOX, 8 patients had chest pain as the presenting complaint that had started within 48 hours of beginning of the 5-FU infusion. In 9 of 10 patients, coronary vasospasm occurred with the first cycle of therapy. All patients made full recovery after discontinuation of infusional 5-FU or capecitabine. All patients subsequently received FLOX with 7 median bolus 5-FU doses (range, 2-22 doses) and 7 median oxaliplatin doses (range, 2-12 doses) at 7 days to 18 months after the event, with 7 patients treated within 4 weeks of the event. FLOX did not cause any cardiovascular adverse events in any of the 10 patients.

Conclusion

Bolus 5-FU in combination with oxaliplatin is safe in patients who have experienced coronary vasospasm with infusional 5-FU or capecitabine.  相似文献   
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Zeitschrift für Psychodrama und Soziometrie - In diesem Artikel der Zeitschrift für Psychodrama und Soziometrie (ZPS) werden die Ergebnisse aktueller Forschung zu Supervision in der...  相似文献   
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