1,721,546 research outputs found
Urinary epidermal growth factor (EGF) levels and epidermal growth factor receptor (EGF-R) expression in human cerebral tumors. Clinical considerations
No full textThe levels of Epidermal Growth Factor (EGF) in urine samples collected from 58 patients (22 low grade gliomas, 13 anaplastic gliomas, 15 glioblastomas and 8 meningiomas) with cerebral tumors admitted at our Institute during 1994 were determined. EGF levels were measured by a specific RIA method. A preoperative and one or two postoperative determinations were performed. Further samples were collected before and at three weeks after postoperative radiotherapy and/or chemotherapy. EGF-Receptor (EGF-R) was determined by an immunohistochemical method on specimens of the same tumor. Preoperative levels showed a positive correlation with the degree of tumor anaplasia. A decrease of the postoperative levels of EGF was observed in all patients who underwent surgery and the entity of the decrease seemed to be well correlated with the extent of the tumoral resection. A strict correlation between EGF levels fluctuations and clinical and neuroradiological features was documented in patients submitted to radiotherapy and/or chemotherapy. The preliminary results on EGF-R expression suggest the existence of a correlation between EGF levels and the receptor expression. In 4 cases of glioblastoma low preoperative levels were associated to an high receptor expression in 2 cases while in the remainder the receptor was not detectable. An high receptor expression is pathognomonic of meningiomatous tissue, even if is not correlated to the biological behaviour and histological features of the neoplasia. These preliminary data suggest the reliability of EGF levels/EGF-R determination in the diagnosis and follow-up of patients with cerebral tumors particularly for those of glial origin. Our data confirmed the role of the EGF system in the development and growth of human gliomas and meningiomas
Low-grade glioma management : a contemporary surgical approach
No full textPURPOSE OF REVIEW:
The primary treatment of low-grade gliomas is still claimed to lack robust supporting evidence. Yet, several investigations were performed in the last 2 decades. To critically review these studies could help in further clarifying the role of surgery aimed at maximal resection.
RECENT FINDINGS:
Despite the lack of randomized clinical trials hampering the performance of appropriate meta-analyses, the increasing amount of evidence pointed toward an aggressive surgical strategy to low-grade glioma. Low-grade glioma surgery has to be performed with the appropriate armamentarium, which is the availability of intraoperative stimulation mapping, especially for those lesions occurring in cortical and subcortical eloquent sites.
SUMMARY:
According to the recently published guidelines, surgical treatment has been increasingly recognized as the initial therapeutic act of choice for patients diagnosed with a presumed low-grade glioma, given that total resection can improve seizure control, progression-free survival and overall survival, while reducing the risk of malignant transformation and preserving patients' functional status
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
Wilson 3D lingual arch during incisors’ advancing orthodontic movement
No full textAIM: To quantify and evaluate the orthodontic movements of incisors and molars during treatment of lower crowding by means of Wilson 3D lingual arch.
MATERIALS AND METHODS: Were considered 70 patients (43 female and 27 male) mean age 12,1 years, during permanent dentition, with Ist class molar relationship and average crowding of lower incisors of 3,6 mm. The orthodontic treatment has been performed without extractions and patient collaboration. The device consisted of a 3 D lingual arch 0.18 thru-crome wire and 2 double vertical connections to solidarize and control tridimensionally lower molar bands by lingual tube, inserted passively to incisors’ cingulum.
RESULTS: It has been showed an average advancement of incisors of 2.38 mm with an unexpected increase of lower molars distalization of 1.32 in 27 cases and with moderate extrusion.
CONCLUSION: This type of lingual arch is very well tollerated by patients; it is not visible, besides it is very easy to activate it. It is very efficaciuos to treat lower incisors crowding without need of patient collaboration
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
- …
