1,720,958 research outputs found
Sigmoid resection for diverticular disease – to ligate or to preserve the inferior mesenteric artery? Results of a systematic review and meta-analysis
No full textAim: In colorectal cancer, ligation of the inferior mesenteric artery (IMA) is a standard surgical approach. In contrast, ligation of the IMA is not mandatory during treatment of diverticular disease. The object of this meta-analysis was to assess if preservation of the IMA reduces the risk of anastomotic leakage. Method: A search was performed up to August 2018 using the following electronic databases: MEDLINE/PubMed, ISI Web of Knowledge and Scopus. The measures of treatment effect utilized risk ratios for dichotomous variables with calculation of the 95% CI. Data analysis was performed using the meta-analysis software Review Manager 5.3. Results: Eight studies met the inclusion criteria and were included in the meta-analysis: two randomized controlled trials (RCTs) and six non-RCTs with 2190 patients (IMA preservation 1353, ligation 837). The rate of anastomotic leakage was higher in the IMA ligation group (6%) than the IMA preservation group (2.4%), but this difference was not statistically significant [risk ratio (RR) 0.59, 95% CI 0.26–1.33, I2 = 55%]. The conversion to laparotomy was significantly lower in the IMA ligation group (5.1%) than in the IMA preservation group (9%) (RR 1.74, 95% CI 1.14–2.65, I2 = 0%). Regarding the other outcomes (anastomotic bleeding, bowel injury and splenic damage), no significant differences between the two techniques were observed. Conclusion: This meta-analysis failed to demonstrate a statistically significant difference in the anastomotic leakage rate when comparing IMA preservation with IMA ligation. Thus, to date there is insufficient evidence to recommend the IMA-preserving technique as mandatory in resection for left-sided colonic diverticular disease
Is a drain necessary after anterior resection of the rectum? A systematic review and meta-analysis
No full textObjective: The anastomotic leak rate in colorectal surgery is highest in patients receiving anterior rectal resections. The placement of prophylactic pelvic drains remains a routine option for preventing postoperative leaks, despite increasing evidence suggesting no clinical benefit. The present study seeks to identify a consensus on the use of prophylactic drains in anterior rectal resections. Methods: A systematic search was conducted of MEDLINE, Scopus, EMBASE, and Cochrane Library databases to identify clinical trials comparing the use of drainage to non-drainage in cases of colorectal anastomosis. Results: Three randomized clinical trials (RCTs) and two controlled clinical trials (CCTs) were identified that met the inclusion criteria, with a total of 1702 patients with rectal cancer who underwent anterior resection: 1206 with a pelvic drain and 496 without a pelvic drain. Meta-analysis showed that the use of a drain did not significantly improve the outcomes of anastomotic leaks; the overall reoperation rate during the 30-day postoperative period and the postoperative mortality were statistically lower in the drained group (OR 2.82, 95% CI 1.33 to 5.97; I 2 = 0%). Conclusions: The use of prophylactic pelvic drainage after anterior rectal resections does not provide significant benefits with respect to anastomotic leaks and overall complication rates. However, an approximately threefold reduction of the postoperative mortality of the drained patients was observed. Given the limitations of the present study, these findings warrant the use of a drain after anterior rectal resection. Nevertheless, due to the low quality of the available data, further multicenter trials with uniform inclusion criteria are needed to evaluate drain usage in the anterior rectal resection
Aberrant left hepatic arteries arising from left gastric arteries and their clinical importance
No full textBackground: The Aberrant Left Hepatic Artery (ALHA) is replaced when it does not originate
from the hepatic artery proper and it is the only supply to that part of the liver, while an
accessory artery coexists with a normal artery. The aim of this systematic review is to
evaluate the incidence of ALHAs including the one arising from the Left Gastric Artery, also
named Hyrtl's artery.
Methods: A literature search in PubMed, SCOPUS,WOS andGoogle Scholarwas performed. The
risk of biaswas assessed bymeans of the AQUA tool. Themain outcomewas the prevalence of
ALHA. Secondary outcomes were the prevalence of the accessory and replaced left hepatic
arteries. A subgroup analysis was conducted by geographic region and type of evaluation.
Results: This review included 57 studies, with a total of 19,284 patients. The majority of the
studies involved the use of radiological techniques -especially Angio-CT-and were performed
in Asia. The overall risk of bias was moderate. The overall prevalence of the ALHA
was 13.52%; the overall prevalence was 8.26% for the Replaced ALHA and 5.55% for the
Accessory ALHA. In the 18 studies that employed Michels' classification, Type II had the
lowest prevalence (0.36%) and Type VII the highest prevalence (6.62%).
Discussion: Some of the studies included did not distinguish between the ‘‘replaced’’ and
‘‘accessory’’ ALHA (34.25%). Some surgical dissection techniques proved insufficient for the
localization of other hepatic arteries. These results suggest that an accurate preoperative
radiological evaluation is needed to localize replaced arteries
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
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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