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Zusammenfassung  Die Chemotherapie hat sich zu einer wesentlichen Säule der Hirntumortherapie entwickelt. Ihr Stellenwert in der Therapie der Gliome ist nicht mehr nur auf die Rezidivtherapie beschränkt. Die Chemotherapie mit Temozolomid ist heute Standard in der Primärtherapie des Glioblastoms. Zur Optimierung der Chemotherapie werden derzeit zahlreiche große Studien durchgeführt, die sich auf den Nachweis einer Methylierung der Promoterregion des MGMT-Gens und eines Verlusts genetischen Materials auf den Chromosomenabschnitten 1p und 19q stützen. Außerhalb solcher Studien wird die Chemotherapie sowohl als Zusatztherapie als auch als Alternative zur Strahlentherapie vor allem bei anaplastischen oligodendroglialen Tumoren und niedriggradigen Gliomen eingesetzt. Primäre Lymphome des Zentralnervensystems sind vermutlich die einzigen Hirntumoren, die mit alleiniger Chemotherapie kurativ behandelt werden können. Bei Hirnmetastasen folgen die Konzepte für die Chemotherapie der für den jeweiligen Primärtumor indizierten Chemotherapie. Zudem werden Strategien der kombinierten Radiochemotherapie mit Temozolomid und mit Topotecan verfolgt. Bei der Meningeosis neoplastica werden je nach Ausbreitungsmuster der Tumorerkrankung Strahlentherapie, systemische Chemotherapie und intrathekale Chemotherapie kombiniert. [ABSTRACT FROM AUTHOR]

Background The Mini-Clinical Evaluation Exercise (Mini-CEX) is a workplace-based assessment tool of potential value in anaesthesia to assess and improve clinical performance. Its reliability and positive educational impact have been reported in other specialities, but not, to date, in anaesthesia. In this study, we evaluated the psychometric characteristics, logistics of application, and impact on the quality of supervision of the Mini-CEX in anaesthesia training. Methods A Mini-CEX encounter consisted of a single specialist anaesthetist observing a trainee over a defined period of time, completing an online Mini-CEX form with the trainee, and providing written and verbal feedback. We sought trainee and supervisor perspectives on its value and ease of use and used Generalizability Theory to estimate reliability. Results We collected 331 assessments from 61 trainees and 58 assessors. Survey responses strongly supported the positive effect of the Mini-CEX on feedback, its relative feasibility, and acceptance as a potential assessment tool. In this cohort, we found variable assessor stringency and low trainee variation. However, a feasible sample of cases and assessors would produce sufficiently precise scores to decide that performance was satisfactory for each trainee with 95% confidence. To generate scores that could discriminate sufficiently between trainees to allow ranking, a much larger sample of cases would be needed. Conclusions The Mini-CEX in anaesthesia has strengths and weaknesses. Strengths include: its perceived very positive educational impact and its relative feasibility. Variable assessor stringency means that large numbers of assessors are required to produce reliable scores. [ABSTRACT FROM AUTHOR]

We investigate the dynamics of ultra-low kinetic energy photoelectrons. Many experimental techniques employed for the detection of photoelectrons require the presence of (more or less) weak electric extraction fields in order to perform the measurement. Our studies show that ultra-low energy photoelectrons exhibit a characteristic shift in their apparent measured momentum when the target system is exposed to such static electric fields. Already fields as weak as 1 V cm–1 have an observable influence on the detected electron momentum. This apparent shift is demonstrated by an experiment on zero energy photoelectrons emitted from He and explained through theoretical model calculations. [ABSTRACT FROM AUTHOR]