1,720,975 research outputs found
Thalamic changes in mesial temporal sclerosis: a limbic system pathology. A case report
No full textHippocampal abnormalities correlated with mesial temporal sclerosis (MTS) are well documented. MTS may be associated with extrahippocampal anomalies involving limbic structures along a known neuroanatomic pathway (Papez circuit). We report a patient with MTS and thalamic changes. Seizure-related thalamic damage could have been caused by abnormal electric discharges from the mamillary body to the anterior thalamus through the mamillothalamic tract. This suggests that MTS is not limited to the temporal lobe but could represent a limbic system pathology
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Spinal dural arterio-venous fistulae lacking spinal cord signal abnormalities: cases reports and literature review.
No full textVariations on the Author
Get PDF“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
Get PDFWe 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
The diagnostic potential of 3-Tesla Magnetic Resonance imaging of brain tumours.
No full textThe clinical application of high magnetic field systems has changed the approach to the diagnosis of brain tumours. Diffusion, perfusion and spectroscopy yield information, respectively, on the degree of cellularity,
neoangiogenesis, presence/absence of necrosis and specific metabolites. Functional magnetic resonance imaging allows the presurgical planning and evaluation of risk and enables the patient to be fully aware at the time of informed consent. All these techniques represent an invaluable tool, otherwise unavailable in vivo, in the diagnosis of brain tumours
Wall motion at 4D-CT angiography and surgical correlation in unruptured intracranial aneurysms: a pilot study.
No full textBACKGROUND:
Unruptured intracranial aneurysms (UIAs) are reported more frequently nowadays but their management is not well established; it depends on different structural features of the aneurysms and on multiple patient's risk factors. With this prospective observational study we report our preliminary experience by using four-dimensional (4D) computed tomographic (CT) angiography with ECG-gated reconstructions in the evaluation of dynamic modifications of the aneurysm wall, as a potential predicting factor of growth or rupture. The novelty of this study consists in correlation between Angio 4D-CT angiography images and surgical findings; only few scientific papers, in fact, have studied this issue.
METHODS:
Thirty-one patients (1 male, 30 females; 59.0±12.7 years old) with 43 unruptured aneurysms (medium size: 5.2±3.0 mm) were studied. ECG-triggered 4D-CT angiography was performed with a 320-detector CT system (Aquilion ONE; Toshiba Medical Systems Corporation, Japan); ECG-gated reconstruction was performed for visualizing local displacement of the aneurysmal wall over a heart cycle. In the aneurysms surgically treated in our institution we were able to compare the macroscopic features of the aneurysm wall with 4D-CTA findings. We performed long-term follow-up on untreated patients.
RESULTS:
Pulsation was detected in 13 of 43 unruptured aneurysms. Eighteen aneurysms were treated: thirteen were surgically treated and five underwent embolization with detachable coil placement. In nine aneurysms surgically treated in our institution (5 with pulsation and 4 without) we observed a significant correlation between 4D-CTA findings and macroscopic features of the aneurysms wall, in particular the pulsations detected at 4D-CTA study have shown to correspond to dark-reddish thinner wall at surgery.
CONCLUSION:
Our data confirm the previous reports concerning the reliability of 4D-CT angiography with ECG-gated reconstructions in defining the dynamic and structural features of the aneurysm wall. Moreover, optimal correlation rate between the findings provided by the 4D-CTA and the macroscopic surgical evaluation support a possible role of this technique to identify aneurysms with a higher risk of rupture
MRI findings in low grade tumours associated with focal cortical dysplasia
No full textMagnetic resonance imaging (MRI) is mandatory to identify the epileptogenic zone in refractory temporal lobe epilepsy (TLE). The correct identification of lesions is essential to obtain good post-surgery seizure control. Low grade tumors (LGT) and focal cortical dysplasia (FCD) ore common findings in symptomatic TLE, and frequently coexist. The aim of thid study was to identify the MRI characteristics in the diagnosis of FDC associated with LGT. We analyzed 24 subjects with TLE who underwent tailored surgery. They all had LGTs. Two expert neuroradiologists analyzed the imaging data and compared them with histological results, hypothesizing the cases of diagnostic errors in the identification of FCD. We selected three exemplary cases to report the most important causes of errors. An incomplete MRI protocol, the large dimensions of the tumour, infiltration and related oedema were the most important factors limiting MRI accuracy. MRI can be limited by an incomplete protocol. In addition, the presence of an LGT may limit the neuroradiological diagnosis of FCD in the temporal lobe. Advanced MRI techniques could help reveal subtle lesion that eluded a previous imaging inspection
- …
