1,721,010 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
Tumorile gastrointestinale stromale gastrice (Revista literaturii)
Full text linkTumorile gastrointestinale stromale (GIST) sunt cele mai frecvente tumori mezenchimale ale tractului gastrointestinal, derivate din celulele Cajal sau precursorii acestora. Conform incidenței stomacul este cea mai frecventă localizare primară. Procesele cheie responsabile de patogenia maladiei rezidă în expresia mutațiilor, mai ales, ale genei c-KIT și rareori ale genei PDGFRA. Diagnosticul se bazează pe caracteristicile morfologice și imunohistochimice ale tumorii care de cele mai multe ori exprimă pozitivitate pentru markerul c-KIT (CD117). Prezentarea clinică a GIST este variabilă, dar simptomele cele mai uzuale includ prezența unei mase abdominale palpabile sau hemoragie gastrointestinală. Pilonul de bază în tratament îl reprezintă rezecția chirurgicală radicală a bolii locale, dar ratele de recurență sunt mari. Managementul modern al bolii GIST combină utilizarea manipulațiilor chirurgicale împreună cu noile direcții ale terapiei țintite
Clnical presentation and surgical treatment of small bowel gastrointestinal stromal tumors: retrospective analisys of 13 cases
Full text linkState University of
Medicine and Pharmacy “Nicolae Testemitanu”, Chişinău, Republic of MoldovaIntroduction: Small bowel tumors are rare malignancies that account for 1-5% of all
gastrointestinal tumors. Despite the progress in recent years in the treatment of small bowel tumors,
their diagnosis is difficult to date because of nonspecific symptoms. To analyze the
clinicopathologic characteristics, diagnostic options and complex treatment of 13 cases of small
bowel gastrointestinal stromal tumors (GIST).
Materials and Methods: 13 consecutive patients with small bowel G ISTs, 5 males (38.5%)
and 8 females (61.5% ), male: female ratio 1:1.6, median age of 55.1 ± 3.3 (95% CE47.90-62.25) years (28-71 years), who underwent surgery from 2008 to 2014, were included in this study. The
clinical records of the patients were analyzed retrospectively.
Results: Abdominal pain (11 cases, 84.6%) was the most common complaint. Abdominal CT
was routinely performed on 9 (69.2%) patients. The preoperative diagnosis was established in 7
(53.8%) cases by abdominal CT. In 5 cases the tumors manifested clinically with complications:
hemorrhage - 2 (15.4% ) patients, obstruction - 2 (15.4%) patients and perforation - 1 (7.7%)
patient. In 3 (23.1% ) patients the tumor was localized in the duodenum, in 8 (61.5%) - in the
jejunum and in 2 (15.4%) - in the ileum. All patients received surgery: 2 - cephalic
pancreatoduodenectomy, 9 - small bowel resection, 1 - duodenal resection and 1 - wedge
resection. The distribution of stages of the disease was as follows: IA=23.1% (n=3), 11=7.7% (n=l),
IIIA=30.7% (n=4), IIIB=23.1% (n=3) and I V= 15.4% (n=2). The mean number of tumors was 2.5 ±
0.7 (from 1 to 9). The mean maximum diameter of the tumors was 9.5 ± 1.3 (from 3.7 to 20) cm.
All 13 patients (100% ) showed positivity for c-KIT(CD l l 7). The overall median number of
mitoses/50HPF was 8.8 ± 1.2 (95% 0 :6 .1 5 -1 1 .5 4 ). The median number of mitoses/50HPF in
patients with high risk of recurrence was 11.1 ± 1.1 (95% 0:8.60-13.62) (from 7 to 18) (n=9) and
3.7 ± 0.5 (95% 0 :2 .2 2 7 - 5.273) (from 3 to 5) (n=4) in patients with low risk of recurrence. A total
of 9 (69.2%) patients received adjuvant treatment with imatinib mesylate 400mg/day.
Conclusion: Clinical manifestations of small bowel GISTs are non-specific and preoperative
diagnosis is difficult. Surgery is the only curative option in the complex treatment of this disease
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
Gastrointestinal autonomic nerve tumor: report of a case
Full text linkIntroduction: Gastrointestinal autonomic nerve tumors (GANT) are a rare subgroup of gastrointestinal stromal tumors (GIST). Their histological appearance is similar to that of other GISTs. Up to date
only about 200 cases were published in English literature.
Aim: We report an additionally case of gastric GANT.
Methods: A 72 years old female patient was admitted with abdominal tumor mass which occurred
in the stomach according CT scan. She underwent a surgery and subtotal gastrectomy was performed.
Results: Postoperative recovery was uneventful. Histological examination and immunohistochemical
analysis revealed the diagnosis of a gastrointestinal autonomic nerve tumor. The immunohistochemical profile of the tumor revealed positive staining to c-kit (CD117), CD34, vimentin and S-100, positive
staining to neuron-specific enolase (NSE) and negative staining to desmin. Three months after initial
diagnosis and surgery the patient is asymptomatic and was scheduled for very close follow up.
Conclusion: Radical surgical resection of gastrointestinal autonomic nerve tumors seems to be the
only available curative approach to date in patients with no metastasis
Tumorile gastrointestinale stromale ale duodenului. Revista literaturii
Full text linkTumorile gastrointestinale stromale (GIST) sunt cele mai frecvente tumori mezenchimale ale tractului gastrointestinal, derivate din celulele Cajal sau precursorii acestora. Conform incidenței, duodenul este una dintre cele mai puțin frecvente localizări primare. Diagnosticul se bazează pe caracteristicile morfologice și imunohistochimice ale tumorii care de cele mai multe ori exprimă pozitivitate pentru markerul c-KIT(CD117). Prezentarea clinică este variabilă, dar cel mai frecvent simptom în GIST duodenal este hemoragia gastrointestinală, urmat de durerea abdominală și, mai puțin frecvent, descoperirea incidentală în cadrul altor investigații de diagnostic. Pilonul de bază în tratament îl reprezintă rezecția chirurgicală radicală a bolii locale, dar ratele de recurență sunt mari. Managementul modern al bolii GIST combină utilizarea intervenției chirurgicale în asociere cu noile direcții de terapie țintită
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
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