339 research outputs found

    Investigation of field induced trapping on floating gates

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    The development of a technology for building electrically alterable read only memories (EAROMs) or reprogrammable read only memories (RPROMs) using a single level metal gate p channel MOS process with all conventional processing steps is outlined. Nonvolatile storage of data is achieved by the use of charged floating gate electrodes. The floating gates are charged by avalanche injection of hot electrodes through gate oxide, and discharged by avalanche injection of hot holes through gate oxide. Three extra diffusion and patterning steps are all that is required to convert a standard p channel MOS process into a nonvolatile memory process. For identification, this nonvolatile memory technology was given the descriptive acronym DIFMOS which stands for Dual Injector, Floating gate MOS

    Cytology for PD-L1 testing : A systematic review

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    Medical writing support, which was in accordance with Good Publication Practice (GPP3) guidelines, was provided by Craig Turner, MSc, of Cirrus Communications (Macclesfield, UK), an Ashfield company, and was funded by AstraZenecaPeer reviewedPublisher PD

    Justification for a Nuclear Global Health Workforce: multidisciplinary analysis of risk, survivability & preparedness, with emphasis on the triage management of thermal burns

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    An assessment of the risks of nuclear conflict and the global preparedness to deal with such a catastrophe. Includes a proposal for triage and management of burn injuries based on a model of what would happen if there was a nuclear attack on Washington DC. Summarises the need for a global nuclear workforce to establish guidelines and strategies to address a nuclear event, the risk of which would appear to be increasingly likely given current world geopolitics

    PD-L1 testing for lung cancer in the UK: recognizing the challenges for implementation.

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    A new approach to the management of non-small-cell lung cancer (NSCLC) has recently emerged that works by manipulating the immune checkpoint controlled by programmed death receptor 1 (PD-1) and its ligand programmed death ligand 1 (PD-L1). Several drugs targeting PD-1 (pembrolizumab and nivolumab) or PD-L1 (atezolizumab, durvalumab, and avelumab) have been approved or are in the late stages of development. Inevitably, the introduction of these drugs will put pressure on healthcare systems, and there is a need to stratify patients to identify those who are most likely to benefit from such treatment. There is evidence that responsiveness to PD-1 inhibitors may be predicted by expression of PD-L1 on neoplastic cells. Hence, there is considerable interest in using PD-L1 immunohistochemical staining to guide the use of PD-1-targeted treatments in patients with NSCLC. This article reviews the current knowledge about PD-L1 testing, and identifies current research requirements. Key factors to consider include the source and timing of sample collection, pre-analytical steps (sample tracking, fixation, tissue processing, sectioning, and tissue prioritization), analytical decisions (choice of biomarker assay/kit and automated staining platform, with verification of standardized assays or validation of laboratory-devised techniques, internal and external quality assurance, and audit), and reporting and interpretation of the results. This review addresses the need for integration of PD-L1 immunohistochemistry with other tests as part of locally agreed pathways and protocols. There remain areas of uncertainty, and guidance should be updated regularly as new information becomes available

    Elevated P53 expression correlates with a history of heavy smoking in squamous cell carcinoma of the head and neck.

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    Expression of the tumour suppressor gene p53 was examined in squamous cell carcinoma of the head and neck using two p53 antibodies, PAb 421 and PAb 1801. Elevated p53 expression was found in 67% of the 73 patients investigated. P53 expression was not found to correlate with whether the patient had been previously treated or not, nor any of the clinico-pathological parameters. However a correlation was found between the patients smoking history and positive p53 staining. Six out of seven non-smokers did not express p53 whereas 29 of 37 heavy smokers were found to have elevated p53 expression (P less than 0.005). Also, of a group of ten patients who had given up smoking more than 5 years ago, nine had elevated expression. Epidemiological studies have shown a correlation between heavy smoking and head and neck cancer. The present study indicate a genetic link for this correlation

    Fractional allele loss data indicate distinct genetic populations in the development of non-small-cell lung cancer.

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    Allelic imbalance or loss of heterozygosity (LOH) has been widely used to assess genetic instability in tumours, and high LOH on chromosome arms 3p, 9p and 17p has been considered to be a common event in non-small-cell lung cancer (NSCLC). We have investigated allelic imbalance in 45 NSCLCs using 92 microsatellite markers on 38 chromosome arms. LOH of 38% was observed on 3p using nine markers, 58% on 9p using 15 markers and 38% on 17p using five markers. Fractional allele loss (FAL) has been calculated for each tumour (FAL is the number of chromosome arms showing LOH/number of informative chromosome arms) and a median FAL value of 0.09 was obtained in the 45 NSCLCs studied. The LOH data were examined on the basis of FAL scores: low FAL (LFAL) (0.00-0.04), medium FAL (MFAL) (0.05-0.13) and high FAL (HFAL) (0.14-0.45) based symmetrically around the median FAL value of 0.09. Tumours with HFAL values showed a very clear polarisation of the LOH data on chromosome arms 3p, 9p and 17p, such that 80% showed loss on 3p, 80% on 9p and 73% on 17p. These incidences of LOH were significantly higher than would be expected, since overall genetic instability in these HFAL tumours ranged from 14% to 45% LOH. Nine of the 14 patients in the LFAL group were found to have no LOH on 3p, 9p or 17p, but five of these had LOH at other sites: i.e. LOH on 5p, 5q, 8p, 13q, 16q and 19q. These results indicate that LFAL patients form a new subset of NSCLC tumours with distinct molecular-initating events, and may represent a discrete genetic population
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