1,720,956 research outputs found
Molecular genetic features and risk assessment in a series of 30 patients who underwent an operation for gastrointestinal stromal tumours
Full text linkBackground: The objective of the study was to investigate the relationship between molecular genetic features and the standard criteria of risk assessment in patients affected by gastrointestinal stromal tumours (GISTs).
Methods: A review was conducted of a series of 30 patients, with a mean age of 67 years, who underwent surgery for primary GISTs. R0 resection was accomplished in 27 patients. CD117, CD34 desmin, vimentin, S-100 and smooth muscle actin were immunohistochemically tested to achieve a diagnosis of GIST. The loss of wild-type KIT or platelet-derived growth factor receptor alpha (PDGFRα) genes was investigated by sequencing the tumour DNA.
Results: Tumour genes mutations were reported in 23 patients (77%), and wild-type in seven. Mutations on the KIT gene occurred in 18 patients, and mutations on the PDGFRα gene in five. The average sizes of the GIST were 8.7 cm, 5.4 cm and 5.9 cm for KIT gene-mutated, PDGFRα gene-mutated and wild-type tumours, respectively. KIT gene mutations were detected in 50% of gastric and in 70% of extragastric GISTs. Moreover, 70% of tumours with a mitotic rate ≥ 5 x 50 highpower fields (HPFs) underwent KIT gene mutations. Conversely, PDGFRα mutations were observed only in gastric GISTs with a mitotic rate ≤ 5 x 50 HPFs. By stratifying GISTs according to classes of risk, KIT mutation was shown in most of the high-risk tumours. PDGFRα mutations occurred exclusively in lower classes of risk.
Conclusion: Molecular analysis data might have a role as a prognostic variable in models of risk assessment for patients with GISTs
Le lesioni del tenue e del mesentere nel trauma addominale chiuso. Esperienza monocentrica.
No full textle lesioni del tenue e del mesentere sono difficili da riconoscere precocemente se non associate ad emoperitoneo importante. Tuttavia un trattamento tardico non impatta negativamente sulla prognosi
THE MANAGEMENT OF SMALL BOWEL AND MESENTERIC INJURIES IN BLUNT ABDOMINAL TRAUMA: LATE DOES NOT MEAN WORSE
No full textIntroduction: Blunt traumatic injuries to small bowel (SB) and its mesentery could be misdiagnosed. Specific symptoms due to perforation and/or ischaemia may develop hours after trauma. Associated abdominal injuries may represent a confounding factor but also mandate surgery through an early diagnosis of SB trauma is cleared. Aim of this study was to detect if a delayed diagnosis of SB blunt trauma may worsen the surgical outcome.
Material and methods: We reviewed 43 patients undergone surgery for SB and mesenteric blunt trauma. Two groups were identified. Group A included 35 patients (69 %) in which SB/mesenteric injuries were recognized and fixed within 12 hrs from admission. of these, 19 pts had immediate laparotomy for hemoperitoneum and shock due to severe multiple abdominal injuries and SB injuries were diagnosed occasionally. Group B included 8 patients (31 %) with isolated SB injuries in which diagnosis and surgery was accomplished more than
12 hrs from admission. Results: Group A patients presented with higher OIS grades. Among these 19 patients had multiple abdominal injuries and 16 of them had isolated SB injuries. Morbidity (34 % group A; 25 % group B, p[0.01) and mortality (14 % group A, nihil group B, p\0.01) were lower in Group B. However, no fatality was related to the SB trauma itself.
Conclusion: In blunt abdominal trauma, the presence of multiple
severe abdominal injuries requiring laparotomy makes possible a
prompt diagnosis of SB/mesenteric lesions. When injuries are isolated,
a delay in diagnosis and surgery could be expected. In these
circumstances however late surgery does not seem to affect the
outcome
Le lesioni del tenue e del mesentere nel trauma addominale chiuso. Esperienza monocentrica decennale.
No full textIntroduzione : Le lesioni del tenue e del mesentere nei traumi addominali chiusi sono di difficile diagnosi clinica, spesso clinicamente sovrastate dai segni relativi alle lesioni associate (traumi splenici, epatici..). La Tc addome che attualmente rappresenta l’esame radiologico di scelta per ottenere un bilancio lesionale fornendo, nelle lesioni entero-mesenteriche in particolare, un’indicazione sulla significatività di tali lesioni. Il trattamento è chirurgico, per via laparotomica o eventualmente laparoscopica e consiste nella resezione-anastomosi o nella riparazione con semplice sutura. Queste lesioni sono temibili soprattutto perché evolvono subdolamente e frequentemente presentano una latenza sintomatologica di 24-48 ore.
Materiali e metodi : 45 pazienti sono stati ricoverati presso l’U.O.Chirurgia d’Urgenza di Pisa tra il 2001 e il 2015 con lesioni del tenue mesenteriale da trauma addominale chiuso di cui 43 trattati chirurgicamente dopo identificazione precoce dagli esami pre-operatori o tardiva dopo la comparsa di segni clinici nelle lesioni isolate o per riscontro intraoperatorio nel corso di interventi eseguiti per le lesioni addominali associate. Il nostro lavoro ha lo scopo di studiare l’outcome clinico nei pazienti con lesioni isolate del tenue e del mesentere, rispetto ai pazienti con lesioni addominali associate per stabilire quanto incide sull’esito terapeutico del paziente il ritardo diagnostico spesso riscontrato nelle lesioni isolate. A tal fine, abbiamo analizzato il grado di lesione del tenue, il tipo di diagnostica effettuata, tempo intercorso prima dell’intervento, la morbidità e la mortalità nei due gruppi di pazienti considerati.
Risultati : 24 pazienti con lesioni isolate del tenue e del mesentere sono stati confrontati con 19 pazienti con interessamento concomitante di più organi intraddominali. Il gruppo delle lesioni associate presenta complessivamente un ISS maggiore, un tempo minore tra evento traumatico e intervento chirurgico, mentre quello delle lesioni isolate richiede esami radiologici complementari con morbidità (30% vs 50%) e mortalità (4% vs 26%) minori. Il ritardo diagnostico e terapeutico nelle lesioni isolate non sembra compromettere in maniera rilevante l’outcome del paziente mentre la presenza di multiple lesioni intraddominali è fortemente correlata con una prognosi peggiore
Conclusione : La diagnosi delle lesioni mesenterico-intestinali è fortemente influenzata dalle lesioni associate: le lesioni di grado più avanzato si associano, per le loro stesse caratteristiche, a segni clinici inequivocabili che portano al’intervento chirurgico immediato mentre è più ambigua l’apparenza delle lesioni di grado I e II. La tendenza al trattamento conservativo del trauma addominale chiuso rende ancora più importante l’identificazione precoce all’imaging di una lesione traumatica maggiore dell’intestino tenue o del mesentere, in particolare conviene mantenere un alto indice di sospetto nei traumi addominali a dinamica maggiore in presenza di “seat belt sindrome” o versamento addominale non associato a lesioni di organi parenchimatosi
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
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