1,721,496 research outputs found
Gallbladder contractility : in vitro and in vivo studies
No full textEThOS - Electronic Theses Online ServiceGBUnited Kingdo
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
[Accepted Manuscript] Cancer subtypes in aetiological research.
Full text linkResearchers often attempt to categorize tumors into more homogeneous subtypes to better predict prognosis or understand pathogenic mechanisms. In clinical research, typically the focus is on prognosis: the tumor subtypes are intended to be associated with specific responses to treatment and/or different clinical outcomes. In aetiological research, the focus is on identifying distinct pathogenic mechanisms, which may involve different risk factors. We used directed acyclic graphs to present a framework for considering potential biases arising in aetiological research of tumor subtypes, when there is incomplete correspondence between the identified subtypes and the underlying pathogenic mechanisms. We identified two main scenarios: (1) weak effect, when the tumor subtypes are identified through combinations of characteristics and some of these characteristics are affected by factors that are unrelated with the underlying pathogenic mechanisms; and (2) lack of causality, when the set of characteristics corresponds with a mechanism that is actually not a cause of the tumor of interest. Examples of the magnitude of bias that can be introduced in these situations are provided. Although categorization of tumors into homogenous subtypes may have important implications for aetiological research and identification of risk factors, the characteristics used to classify tumors into subtypes should be as close as possible to the actual pathogenic mechanisms to avoid interpretative biases. Whenever our knowledge of these mechanisms is limited, research into risk factors for tumor subtypes should first aim to causally link the characteristics to the pathogenic mechanisms
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Feasibility of recruiting a birth cohort through the Internet: the experience of the NINFEA cohort
No full text"Stretching the limits of laparoscopic surgery": two-stage laparoscopic liver resection
No full textIntroduction: the safety and feasibility of laparoscopic liver resections have recently been confirmed. This has encouraged laparoscopic surgeons to widen the indications and push the boundaries in laparoscopic liver resections. However, a complete laparoscopic two-stage liver resection has not been reported previously.Aim: the aim of this work was to assess the feasibility and safety of the two-stage laparoscopic liver resection for metastatic disease.Methods: the two-stage laparoscopic liver resection was safely performed in a 58-year-old man with colorectal liver metastasis (one in segment 2/3 and one in the right lobe). A left lateral sectionectomy was first performed, followed by right portal vein embolization 1 week later, and a nonanatomic resection of the right liver was performed after 6 weeks.Conclusions: laparoscopic liver surgery is gaining popularity and major procedures can now be performed in centers with wide experience. The laparoscopic approach should always be considered for left lateral sectionectomy, and in selected cases, a complete laparoscopic two-stage resection can safely be performe
Escalation related decision-making in acute deterioration: A retrospective case note review
No full textAim To describe how decision making inter-relates with the sequence of events in individuals who die during admission and identify situations where formal treatment escalation plans (TEPs) may have utility. Design and methods A retrospective case note review using stratified sampling. Two data analysis methods were applied concurrently: directed content analysis and care management process mapping via annotated timelines for each case. Analysis was followed by expert clinician review (n=7), contributing to data interpretation.Sample 45 cases, age range 38–96 years, 23 females and 22 males. Length of admission ranged from <24 hours to 97 days.Results Process mapping led to a typology of care management, encompassing four trajectories: early de-escalation due to catastrophic event; treatment with curative intent throughout; treatment with curative intent until significant point; and early treatment limits set. Directed content analysis revealed a number of contextual issues influencing decision making. Three categories were identified: multiple clinician involvement, family involvement and lack of planning clarity; all framed by clinical complexity and uncertainty.Conclusions The review highlighted the complex care management and related decision-making processes for individuals who face acute deterioration. These processes involved multiple clinicians, from numerous specialities,often within hierarchical teams. The review identified the need for visible and clear management plans, in spite of the frame of clinical uncertainty. Formal TEPs can be used to convey such a set of plans. Opportunities need to be created for patients and their families to request TEPs, in consultation with the clinicians who know them best, outside of the traumatic circumstances of acute deterioration
Oncological outcomes of laparoscopic surgery of liver metastases: a single-centre experience
No full textIn the era of multimodal management of liver metastases, surgical resection remains the only curative option, with open approach still being referred to as the standard of care. Currently, the feasibility and benefits of the laparoscopic approach for liver resection have been largely demonstrated. However, its oncologic adequacy remains to be confirmed. The aim of this study is to report the oncological results of laparoscopic liver resection for metastatic disease in a single-centre experience. A single-centre database of 413 laparoscopic liver resections was reviewed and procedures for liver metastases were selected. The assessment of oncologic outcomes included analysis of minimal tumour-free margin, R1 resection rate and 3-year survival. The feasibility and safety of the procedures were also evaluated through analysis of perioperative outcomes. The study comprised 209 patients (294 procedures). Colorectal liver metastases were the commonest indication (67.9%). Fourteen patients had conversion (6.7%) and oncological concern was the commonest reason for conversion (42.8%). Median tumour-free margin was 10 mm and complete radical resections were achieved in 211 of 218 curative-intent procedures (96.7%). For patients affected by colorectal liver metastases, 1- and 3-year OS resulted 85.9 and 66.7%. For patients affected by neuroendocrine liver metastases, 1- and 3-year OS resulted 93 and 77.8%. Among the patients with metastases from other primaries, 1- and 3-year OS were 83.3 and 70.5%. The laparoscopic approach is a safe and valid option in the treatment of patients with metastatic liver disease undergoing curative resection. It does offer significant perioperative benefits without compromise of oncologic outcomes
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