1,720,972 research outputs found
Accuracy of transrectal ultrasound after preoperative radiochemotherapy compared to computed tomography and magnetic resonance in locally advanced rectal cancer.
No full textINTRODUCTION:
The aim of the present study was to compare the restaging results obtained by transrectal ultrasound (TRUS), computed tomography (CT), and magnetic resonance imaging (MRI) performed after preoperative chemoradiation with pathologic staging of the operative specimen.
METHODS:
From January 2008 to December 2009, all the consecutive patients with locally advanced rectal cancer that underwent neoadjuvant therapy at our department were evaluated. The results of diagnostic examinations and the definitive pathological examination were considered and compared.
RESULTS:
Thirty-seven patients were included in the study (27 males, 73%), mean age was 65.5 years (range 45-82 years). In all the patients TRUS and CT and in 20 patients MRI were performed before and after the treatment. Concerning the depth of invasion after treatment TRUS agreed with histopathology in 25/37 patients (67.5%), CT agreed in 22/37 cases (59.5%), and MRI in 12/20 cases (60%). Considering only neoplasia with stage T3, TRUS agreed in 23/24 cases (96%), CT in 19 cases (79%), and MRI in 10/12 cases (83.5%). Considering the tumors that did not exceed the rectal wall (T0, T1, and T2), TRUS agreed with histology in 2/13 cases (15.5%), CT in 3/13 cases (23%), and MRI 2/8 cases (25%). Concerning the presence of positive lymph nodes TRUS agreed with histology in 28/37 cases (75.5%), while CT agreed in 21/37 cases (56.5%) and MRI in 11/20 cases (55%). The concordance between the techniques was found to be low.
CONCLUSIONS:
Transrectal ultrasonography resulted as the most accurate method to determine neoplastic wall infiltration and lymph node involvement even after radiochemotherapy. In most cases, considering the poor correlation between the diagnostic procedures and the disagreement of the results, a restaging performed only with TRUS could be proposed, limiting the use of the other imaging methods to selected cases
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
Laparoscopy Versus Robotic Surgery for Colorectal Cancer: A Single-Center Initial Experience
No full textBackground. Minimally invasive approach has gained interest in the treatment of patients with colorectal cancer. The purpose of this study is to analyze the differences between laparoscopy and robotics for colorectal cancer in terms of oncologic and clinical outcomes in an initial experience of a single center. Materials and Methods. Clinico-pathological data of 100 patients surgically treated for colorectal cancer from March 2008 to April 2014 with laparoscopy and robotics were analyzed. The procedures were right colonic, left colonic, and rectal resections. A comparison between the laparoscopic and robotic resections was made and an analysis of the first and the last procedures in the 2 groups was performed. Results. Forty-two patients underwent robotic resection and 58 underwent laparoscopic resection. The postoperative mortality was 1%. The number of harvested lymph nodes was higher in robotics. The conversion rate was 7.1% for robotics and 3.4% for laparoscopy. The operative time was lower in laparoscopy for all the procedures. No differences were found between the first and the last procedures in the 2 groups. Conclusions. This initial experience has shown that robotic surgery for the treatment of colorectal adenocarcinoma is a feasible and safe procedure in terms of oncologic and clinical outcomes, although an appropriate learning curve is necessary. Further investigation is needed to demonstrate real advantages of robotics over laparoscopy
Porcelain gallbladder and its relationship to cancer
Full text linkBackground: Porcelain gallbladder (PGB) is defined as calcium deposits encrusting the internal visceral layer, which becomes hard, brittle, and bluish. Porcelain gallbladder is rare and has been found in less than 1% of routine cholecystectomy specimens. Several studies report an incidence of gallbladder carcinoma (GBC) associated with gallbladder calcification varying between 12.5 and 61%, data which have been known for 60 years. There is a lack of information concerning PGB and its association with GBC, and the aim of this study is to better define this relationship. Methods: A total of 10 patients were found to have PGB in 1050 consecutive routine surgical cholecystectomies. Clinical and laboratory findings, gallbladder histologic examination, bile culture, and bile pH were related to stone composition analysis performed by X‐ray diffraction using Perkin–Elmer (Perkin Elmer Corp. Norwalk, CT, US) 1625 FTIR. Results: Among the 10 patients with PGB, complete calcification of the entire gallbladder wall was present in six cases, while four patients had partial calcification. Gallstones were present in all cases of PGB, multiple stones in nine cases and a single stone in one case. Bile culture was performed in all patients of the series. Among the 10 cases with PGB, culture was positive in two cases. Conclusion: PGB is a disease as rare as it is subtle. Moreover, the chronic stimulation by stones can generate an initial dysplasia that will subsequently turn into a neoplasm: the cancerization risk is probably no different from long-standing cholesterol or combined stones, but as risk factor for cancer it requires early cholecystectomy
Assessing the feasibility of full robotic interaortocaval nodal dissection for locally advanced gastric cancer
No full textBackground: The clinical value of super-extended lymph node dissection (D2+) is still debated. This procedure has not been reported using the laparoscopic or robotic approach. Although this technique, in low-volume centres, could lead to an increased risk of morbidity, in high-volume centres morbidity and mortality are similar to those of the standard D2 lymphadenectomy. Robotic surgery could overcome the limitations of laparoscopic surgery, especially in the removal of posterior nodal stations. In this report we describe the feasibility of fully robotic interaortocaval lymphadenectomy, following similar steps to those of the traditional open approach. Methods: The procedure was a total gastrectomy with oesophago-jejunal Roux-en-Y reconstruction in a 73 year-old male patient with clinically advanced (cT3) gastric adenocarcinoma, located in the lesser curvature (middle-upper third). The da Vinci® Si HD with a double-docking robot set-up was employed. Results: The histological specimen examination showed a pT4aN3bM0, Borrmann type III, intestinal histotype, G3 gastric adenocarcinoma. No involvement of resection margins was found (R0 resection). The numbers of total harvested and positive nodes were 57 and 41, respectively; the number of harvested interaortocaval nodes was 14, and all of them were negative for tumour involvement. Operative time for lymphadenectomy was comparable with that of the traditional open approach. The postoperative period was uneventful and hospital stay was 11 days. Conclusions: Robotic-assisted interaortocaval lymphadenectomy is a feasible technique in high-volume centres for gastric cancer surgery, and should be considered in curative surgery for selected advanced cases, especially for the high-risk group of lymph node metastases in the posterior area
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
Robotic single docking total colectomy for ulcerative colitis: First experience with a novel technique
No full textIntroduction: We describe a novel technique that could aid the surgeon to perform a total proctocolectomy with a single docking position of the da Vinci Si HD System. Methods: Patients were positioned in 20° Trendelenburg lithotomy split legs position. A 12-mm trocar was for camera and 3 more trocars were placed: two robotics on left and right flanks and one laparoscopic in left iliac fossa. The robot was docked between the legs of the patients. Results: Four proctocolectomies were performed. Mean operative time was 235 min (range 215-255); mean blood loss was 100 cc (range 50-200). Median post-operative stay was 6 days. Overall morbidity was 75%, whereas major complications occurred in 25%. Post-operative mortality was null. Conclusions: The robotic single docking approach to perform total proctocolectomy for ulcerative colitis is a time-saving technique respect to the multiple docking approach
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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