4,849 research outputs found

    SCREENING FOR HEPATITIS C Response from Hepatitis C Trust, BASL, BIA, BVHG, BSG, and BHIVA to article asking whether widespread screening for hepatitis C is justified

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    This is the peer reviewed published version of the following article: Response from Hepatitis C Trust, BASL, BIA, BVHG, BSG, and BHIVA to article asking whether widespread screening for hepatitis C is justified, which has been published in final form at 10.1136/bmj.h998. This article may be used for non-commercial purposes in accordance with BMJ's Terms and Conditions for Self-Archiving.This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/ by/4.0

    Direct esterification of poly (ethylene glycol) with amino acid hydrochlorides

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    Diesters of poly (ethylene glycol) with various a amino acid hydrochlorides were synthesized using dicyclohexyl carbodiimide as coupling agent. The use of hydrochloride as amino protecting group in dicyclohexyl carbodiimide mediated condensation reactions of amino acids was demonstrated for the first time

    Reconstructing 3D x-ray CT images of polymer gel dosimeters using the zero-scan method

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    In this study x-ray CT has been used to produce a 3D image of an irradiated PAGAT gel sample, with noise-reduction achieved using the ‘zero-scan’ method. The gel was repeatedly CT scanned and a linear fit to the varying Hounsfield unit of each pixel in the 3D volume was evaluated across the repeated scans, allowing a zero-scan extrapolation of the image to be obtained. To minimise heating of the CT scanner’s x-ray tube, this study used a large slice thickness (1 cm), to provide image slices across the irradiated region of the gel, and a relatively small number of CT scans (63), to extrapolate the zero-scan image. The resulting set of transverse images shows reduced noise compared to images from the initial CT scan of the gel, without being degraded by the additional radiation dose delivered to the gel during the repeated scanning. The full, 3D image of the gel has a low spatial resolution in the longitudinal direction, due to the selected scan parameters. Nonetheless, important features of the dose distribution are apparent in the 3D x-ray CT scan of the gel. The results of this study demonstrate that the zero-scan extrapolation method can be applied to the reconstruction of multiple x-ray CT slices, to provide useful 2D and 3D images of irradiated dosimetry gels

    Reproducibility of measurements of oestrogen-receptor concentration in breast cancer.

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    The reproducibility of measurements of oestrogen-receptor activity has been examined in multiple specimens from a rabbit uterus, a rat mammary tumour and human breast tumours. The relationship between receptor concentration and tumour histology has also been investigated in 11 large primary tumours. In the animal tissues, receptor measurements were relatively reproducible (coefficient of variance: wet wt. basis 16-17%, protein basis 16-21%) but in human breast tumours receptor activity varied considerably (c.v.: wet wt. basis, 22-125%; protein basis, 28-72%). In addition to these variations in receptor activity within tumours, there was a difference between tumours, as demonstrated by an analysis of variance (P less than 0.01). In the 11 primary breast cancers selected for study, the level of receptor activity was related to menopausal status and the tumour content of the specimen. We conclude that the receptor activity detected varies within a tumour and depends upon the tumour content of the biopsy specimen. Predictions based on precise quantitation of receptor concentrations may therefore necessitate replicate tumour sampling and correction for the fraction of non-tumour tissue in each sample

    Controlling Light Through Optical Disordered Media : Transmission Matrix Approach

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    We experimentally measure the monochromatic transmission matrix (TM) of an optical multiple scattering medium using a spatial light modulator together with a phase-shifting interferometry measurement method. The TM contains all information needed to shape the scattered output field at will or to detect an image through the medium. We confront theory and experiment for these applications and we study the effect of noise on the reconstruction method. We also extracted from the TM informations about the statistical properties of the medium and the light transport whitin it. In particular, we are able to isolate the contributions of the Memory Effect (ME) and measure its attenuation length

    Trends in health sciences library and information science research: an analysis of research publications in the \u3cem\u3eBulletin of the Medical Library Association\u3c/em\u3e and \u3cem\u3eJournal of the Medical Library Association\u3c/em\u3e from 1991 to 2007

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    OBJECTIVE: This study analyzed trends in research activity as represented in the published research in the leading peer-reviewed professional journal for health sciences librarianship. METHODOLOGY: Research articles were identified from the Bulletin of the Medical Library Association and Journal of the Medical Library Association (1991-2007). Using content analysis and bibliometric techniques, data were collected for each article on the (1) subject, (2) research method, (3) analytical technique used, (4) number of authors, (5) number of citations, (6) first author affiliation, and (7) funding source. The results were compared to a previous study, covering the period 1966 to 1990, to identify changes over time. RESULTS: Of the 930 articles examined, 474 (51%) were identified as research articles. Survey (n = 174, 37.1%) was the most common methodology employed, quantitative descriptive statistics (n = 298, 63.5%) the most used analytical technique, and applied topics (n = 332, 70%) the most common type of subject studied. The majority of first authors were associated with an academic health sciences library (n = 264, 55.7%). Only 27.4% (n = 130) of studies identified a funding source. CONCLUSION: This study\u27s findings demonstrate that progress is being made in health sciences librarianship research. There is, however, room for improvement in terms of research methodologies used, proportion of applied versus theoretical research, and elimination of barriers to conducting research for practicing librarians

    Outcome of ATP-based tumor chemosensitivity assay directed chemotherapy in heavily pre-treated recurrent ovarian carcinoma

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    BACKGROUND: We wished to evaluate the clinical response following ATP-Tumor Chemosensitivity Assay (ATP-TCA) directed salvage chemotherapy in a series of UK patients with advanced ovarian cancer. The results are compared with that of a similar assay used in a different country in terms of evaluability and clinical endpoints. METHODS: From November 1998 to November 2001, 46 patients with pre-treated, advanced ovarian cancer were given a total of 56 courses of chemotherapy based on in-vitro ATP-TCA responses obtained from fresh tumor samples or ascites. Forty-four patients were evaluable for results. Of these, 18 patients had clinically platinum resistant disease (relapse < 6 months after first course of chemotherapy). There was evidence of cisplatin resistance in 31 patients from their first ATP-TCA. Response to treatment was assessed by radiology, clinical assessment and tumor marker level (CA 125). RESULTS: The overall response rate was 59% (33/56) per course of chemotherapy, including 12 complete responses, 21 partial responses, 6 with stable disease, and 15 with progressive disease. Two patients were not evaluable for response having received just one cycle of chemotherapy: if these were excluded the response rate is 61%. Fifteen patients are still alive. Median progression free survival (PFS) was 6.6 months per course of chemotherapy; median overall survival (OAS) for each patient following the start of TCA-directed therapy was 10.4 months (95% confidence interval 7.9-12.8 months). CONCLUSION: The results show similar response rates to previous studies using ATP-TCA directed therapy in recurrent ovarian cancer. The assay shows high evaluability and this study adds weight to the reproducibility of results from different centre
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