1,721,049 research outputs found
The role of gastrin and CCK-B/gastrin receptor in hepatocellular and pancreatic cancers
No full textThe in vitro effects of gastrin, glycine-extended gastrin, anti-gastrin antibodies and the CCK-B receptor antagonist PD135,158 were assessed on hepatoma cell lines. This study demonstrated that amidated gastrin and glycine-extended gastrin stimulated some hepatoma cell lines and that this could be abrogated by anti-gastrin agents. Tissue sections from patients with hepatocellular carcinoma, fibrolamellar carcinoma, cholangiocarcinoma as well as normal liver biopsies were assessed for expression of CCK-B receptor and gastrin isoforms. The results showed that most liver tumours express CCK-B receptor and precursor forms of gastrin. There appears to be little expression of the receptor and no expression of precursor forms of gastrin in normal liver. Tissue sections from patients with pancreatic cancer and normal pancreas were assessed for expression of CCK-B receptor and gastrin isoforms. The results showed that the normal pancreas showed no expression of receptor or gastrin isoforms except for occasional cells in the islets. The pancreatic cancer patients showed definite expression of CCK-B receptor and predominantly precursor forms of cancer. Studies were performed to identify the cellular sites of expression of the CCK-B receptor in the known CCK-B receptor bearing pancreatic acinar AR42J cells. Using immunoelectron microscopy and western blotting techniques the CCK-B receptor was shown to be expressed not only on the cell membrane, but also in the cytoplasm and nucleus of cells. In conclusion the expression of the gastrin precursor forms is most likely related to the autocrine production of gastrin by cancer cells. The nuclear expression of the receptor is a novel finding and may contribute to cellular proliferation in cancer cells. Gastrin and its receptor appear to be important in the growth of a variety of cancers and the understanding of this proliferative effect has led to the development of anti-gastrin agents now undergoing therapeutic clinical trials in gastrointestinal and pancreatic cancers.</p
Treatment challenges in and outside a specialist network setting: Pancreatic neuroendocrine tumours
Full text linkPancreatic Neuroendocrine Neoplasms comprise a group of rare tumours with special biology, an often indolent behaviour and particular diagnostic and therapeutic requirements. The specialized biochemical tests and radiological investigations, the complexity of surgical options and the variety of medical treatments that require individual tailoring, mandate a multidisciplinary approach that can be optimally achieved through an organized network. The present study describes currents concepts in the management of these tumours as well as an insight into the challenges of delivering the pathway in and outside a Network
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
Comparison of the impact of<sup> 68</sup>Ga-DOTATATE and <sup>18</sup>F-FDG PET/CT on clinical management in patients with neuroendocrine tumors
No full textThis study aimed to assess the clinical impact of 68Ga-DOTATATE and 18F-FDG with respect to the management plan and to evaluate the prognostic value of both tracers. Methods: a total of 104 patients (55 male and 49 female; median age, 58 y; range, 20-90 y) with histologically proven neuroendocrine tumors (NETs) underwent both 68Ga-DOTATATE and 18F-FDG PET/CT. Twenty-eight patients (26.9%) had poorly differentiated tumors, and 76 (73.1%) had well differentiated tumors. PET/CT results and SUVs were compared with prognostic factors such as histologic grade (G1, G2, or G3, for low-grade [well differentiated], intermediate-grade [moderately differentiated], and high-grade [poorly differentiated], respectively), chromogranin A, and proliferation index (Ki-67). Results: the 68Ga-DOTATATE and 18F-FDG PET/CT findings were discordant in 65 patients (62.5%) and concordant in 39 patients (37.5%). The results changed the therapeutic plan in 84 patients (80.8%). In 22 patients (21.1%), decision making was based on the 18F-FDG findings; in 32 (30.8%), on the findings with both radiotracers; and in 50 (48.1%), on the 68Ga-DOTATATE findings. The most frequent management decision based on 18F-FDG was initiation of chemotherapy (10 patients, 47.6%). The most common treatment decision due to 68Ga-DOTATATE was initiation of peptide receptor radionuclide therapy (14 patients, 27.4%). In 11 (39.2%) of 28 patients with poorly differentiated NETs, the management decision was based on only the 18F-FDG results. For 68Ga-DOTATATE, SUVmax was higher for G1 tumors and lower for G3 tumors (P 5 0.012). However, no significant differences in 18F-FDGderived SUVs were observed between different grades (P 5 0.38). The Mann-Whitney test showed significant differences in 68Ga-DOTATATE SUVmax between tumors with a Ki-67 of less than 5% and tumors with a Ki-67 of more than 5% (P 5 0.004), without significance differences in 18F-FDG SUVmax. Log-rank analysis showed statistically significant differences in survival for patients with bone metastasis versus soft-Tissue or no metastasis for both 18F-FDG (P 5 0.037) and 68Ga-DOTATATE (P 5 0.047). Overall survival declined rapidly with increasing grade (P 5 0.001), at an estimated 91 mo for G1, 59 mo for G2, and 48 mo for G3.Conclusion: 18F-FDG PET/CT had no clinical impact on G1 NETs and a moderate impact on G2 NETs. However, in poorly differentiated NETs, 18F-FDG PET/CT plays a significant clinical role in combination with 68Ga-DOTATATE. 68Ga DOTATATE SUVmax relates to grade and Ki-67 and can be used prognostically. Key Words: 68Ga-DOTATATE; 18F-FDG PET/CT; neuroendocrine tumors; clinical impact; prognosis
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
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
- …
