1,720,972 research outputs found
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
Clinical and oncological value of preoperative BMI in gastric cancer patients: A single center experience
No full textIntroduction. The impact of preoperative BMI on surgical outcomes and long-term survival of gastric cancer patients was investigated in various reports with contrasting results. Materials & Methods. A total of 378 patients who underwent a surgical resection for primary gastric cancer between 1994 and 2011 were retrospectively studied. Patients were stratified according to BMI into a normal group (<25, group A), an overweight group (25-30, group B), and an obesity group (≥30, group C). These 3 groups were compared according to clinical-pathological characteristics, surgical treatment, and long-term survival. Results. No significant correlations between BMI and TNM (2010), UICC stage (2010), Lauren's histological type, surgical results, lymph node dissection, and postoperative morbidity and mortality were observed. Factors related to higher BMI were male gender P < 0.05, diabetes P < 0.001, and serum blood proteins P < 0.01. A trend to fewer lymph nodes retrieved during gastrectomy with lymphadenectomy in overweight patients (B and C groups) was observed, although not statistically significant. There was no difference in overall survival or disease-specific survival between the three groups. Conclusion. According to our data, BMI should not be considered a significant predictor of postoperative complications or long-term result in gastric cancer patients
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
Is robotic better than laparoscopic approach for right colectomy? A cohort study from two Tuscany centers
No full textLa chirurgia miniinvasiva sta sostituendo la chirurgia a cielo aperto in quasi tutte le discipline chirurgiche. L’uso del robot nella chirurgia laparoscopica invece sta diventando sempre più frequente. Ad esso vengono riconosciuti dei vantaggi come la migliore visualizzazione, maggiore stabilità, più grande amplitudine di movimento del polso robotico, la filtrazione del tremore e degli svantaggi come il più lungo tempo operatorio e il costo più alto. Alcuni studi hanno cercato di confrontare la chirurgia robotica e laparoscopica con risultati discordanti. La diffusione della tecnica CME per l’emicolectomia destra potrebbe beneficiare dalla piattaforma robotica. Lo scopo del nostro studio è stato il confronto ai risultati a breve termine dell’emicolectomia destra robotica e laparoscopica. I dati delle procedure di emicolectomia destra robotica e laparoscopica eseguite dal 1 gennaio 2013 al 31 dicembre 31 2019 in due ospedali toscani sono stati raccolti e analizzati retrospettivamente. Sono stati confrontati la degenza media, le complicanze, la canalizzazione ai gas, il tempo operatorio, la percentuale di conversione e il numero dei linfonodi asportati fra le due tecniche robotiche. Il numero totale dei pazienti sottoposti a emicolectomia destra robotica e laparoscopica è stato 211. Sedici pazienti sono stati esclusi dallo studio. Dei 195 pazienti inclusi, 143 sono stati operati con la tecnica robotica e 52 con la tecnica laparoscopica. Non ci sono state differenze riguardo la degenza media (7 giorni per entrambi), canalizzazione ai gas (4 giorni per entrambe te procedure), la deiscenza anastomotica (2 con la tecnica robotica e 2 in laparoscopia), e le complicanze Clavien- Dindo 3-5. Il tempo operatorio (215 vs 175 minuti) e il numero dei linfonodi asportati (19 vs 15) è stato significativamente più grande nell’approccio robotico.Robotic surgery is becoming more and more frequent. In colon surgery it can be used safely with similar results to laparoscopic surgery. The objective of our work is to retrospectively compare the short-term results (30 days) of robotic and laparoscopic right hemicolectomy. It will be helpful to understand if there are any advantages of robotic over laparoscopic surgery. METHODS: Data of miniinvasive (laparoscopic and robotic) right colectomy procedures performed from January 1, 2013 to December 31, 2019 in two Tuscany hospitals were retrospectively collected and analyzed. The mean hospital stay, complication rate, flatus pass, operative time, conversion rate and the number of removed lymph nodes, between the two methods have been compared. RESULTS: The total number of the patients that underwent right miniinvasive colectomy was 211. Sixteen patients were excluded from the study. Of the 195 included patients, 143 were operated with the robotic approach, and 52 with the laparoscopic one. There was no significant difference between the mean hospital stay (7 days in both), canalization to gas (4 days in both), anastomotic dehiscence (2 in robotic and 1 in laparoscopy), and Clavien Dindo 3 - 5 grade complications. The operation time (215 vs 175 min) and the number of retrieved lymph nodes (19 vs 15) were significantly greater in the robotic approach. CONCLUSION: The robotic approach may be advantageous in terms of surgical radicality with the price of a greater operative time. KEY WORDS: Laparoscopic, Right colectomy, Robotic
Recurrence after surgery in esophago-gastric junction adenocarcinoma: Current management and future perspectives
No full textRecurrent esophago-gastric junction adenocarcinoma is not a rare event and its correct management is still debated. Many approaches for the treatment of these patients exist, but only few studies compare the different techniques. Most of the studies are retrospectives series and describe the experiences of single institutions in the treatment of recurrent esophageal and esophago-gastric junction cancers. Nowadays surgery is still the main and only curative treatment. Other alternative palliative therapies could be endoscopic stent placement and balloon dilation, photodynamic therapy, thermal tumor ablation (laser photoablation and Argon plasma coagulation), radiation therapy and brachytherapy, and chemotherapy. The aim of this review is to investigate the different rates, patterns and timings of recurrence of this tumor, and to explain the various approaches used for the treatment of recurrent esophago-gastric junction cancer
Is sleeve gastrectomy a therapeutic procedure for all obese patients?
No full textBackground: Laparoscopic sleeve gastrectomy (LSG) is a worldwide surgical procedure for morbid obesity. However patients selection is still anecdotal. The aim of this study is to analyse clinical and anthropometric parameters correlated with LSG and to check the validity of this procedure for different categories of obese patients. Methods: Two-hundred one consecutive patients were submitted to LSG as a primary bariatric procedure between 2008 and 2014. One year follow-up was completed in 159 patients. Smaller groups of patients completed 2 and 3 years follow-up (78, 46 patients respectively). Median preoperative body mass index (BMI) was 45.4 kg/m2 (range: 34.8-73.8); 135 patients (80%) had one or more comorbidities. Potential correlations between age, gender, preoperative BMI, preoperative excess weight, early excess weight loss (EWL) and 1 and 3 year-EWL were investigated. Results: All procedures were regularly completed with laparoscopic approach without conversion to laparotomy. Postoperative complications occurred in six patients (3.7%); no postoperative mortality was observed. Median one-year BMI and EWL were 32.8 kg/m2 and 55.34%, respectively. Three year-EWL was significantly influenced by age, and early EWL. A complete normalization of glycemic levels after the three-year follow-up was also observed in high percentage of diabetic patients. In patients with preoperative BMI>50 kg/m2 we observed most failure cases in terms of EWL and the worst metabolic results. Conclusions: Our experience indicates that LSG is a safe procedure with satisfactory three-year late weight loss in patients with preoperative BMI <50 kg/m2. Promising results, in terms of improvements of comorbidities, were also observed. These results make LSG one of the most attractive first stage surgical procedure for morbid obesity
The pattern of lymph node metastases in microsatellite unstable gastric cancer
No full textBackground Microsatellite instability (MSI) is one of the new groups of molecular divisions of gastric cancer (GC). The aim of this study was to investigate the pattern of lymph node metastasis according to MSI status. Methods MSI analysis of 361 GC patients with information about lymph node stations was performed using 5 quasimonomorphic mononucleotide repeats. The metastasis rates for each lymphatic station was analyzed, combined with clinicopathologic characteristics. Stations were divided into compartments 1–3 on the basis of Japanese Classification. A median number (interquartile range, IQR) of 33 (18–50) lymph nodes were removed and analyzed. Results N0 status was observed in 53.7% MSI patients, and in 29.7% microsatellite stable (MSS) (p < 0.001).The median value of involved nodes was 1 in MSI vs. 5 in MSS (p < 0.001). Furthermore, the number of involved node stations was significantly lower in the MSI group (p < 0.001). MSS tumors showed a higher propensity to spread to second and third compartment nodes. In absence of lymphovascular invasion only 3.2% cases demonstrated positive nodes beyond the first compartment. Skip metastases were seen in 6.1% MSS patients and 0% MSI (p = 0.011). No difference in the 10-year cancer related survival among MSI and MSS patients was found, for both those with 1st compartment (p = 0.223) and with 2nd compartment involvement (p = 0.814). Conclusions MSI GC shows a high rate of N0 stage, a lower number of lymph node metastases, and a less extensive spread to lymph node stations than MSS tumors. These data indicate that tailored lymphadenectomy may be investigated for these patients
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
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