1,721,021 research outputs found
Thyroid hormone therapy in differentiated thyroid cancer
No full textSurgery-with or without postoperative radioiodine-is the standard of care for most patients with differentiated thyroid carcinoma (DTC). Thyroid hormone replacement therapy is the mainstay of long-term medical management. Patients treated with total thyroidectomy and some who undergo lobectomy alone require thyroid hormone therapy to restore euthyroidism with normal serum thyroid-stimulating hormone (TSH) levels. Because TSH acts as a growth factor for thyroid follicular cells (including those that are neoplastic), it can potentially affect the onset and/or progression of follicular-cell derived thyroid cancer. For this reason, some patients are placed on thyroid hormone therapy at doses that suppress secretion of TSH (suppression therapy). This mini-review looks at the potential benefits and risks of this practice in patients diagnosed with DTC. Aggressive TSH-suppressive therapy is of little or no benefit to the vast majority of patients with DTC. Practice guidelines, therefore, recommend a graded algorithm in which the potential benefits of suppression are weighed against the associated cardiovascular and skeletal risks. Large randomized controlled studies are needed to confirm the presumed oncological benefits of TSH-suppression and its causal role in adverse cardiac, skeletal, and quality of life effects and to assess the efficacy of TSH normalization in reversing or reducing these effects
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
Low-risk papillary thyroid microcarcinoma: Optimal management toward a more conservative approach
No full textThe incidence of papillary thyroid microcarcinoma (microPTC) has dramatically increased in the last decades. Most of these tumors remain small and clinically “silent”, only small number progress. Although thyroid surgery used to be the only therapeutic approach, recent guidelines now consider active surveillance for low-risk microPTC. For this reason, more accurate risk stratification of microPTC is needed. The optimal management of low-risk microPTC through accurate risk stratification represents a major clinical issue
Thyroid diseases in elderly.
No full textThyroid diseases are the commonest endocrine disorders in the general population. In most of the cases, they are consistent with benign conditions which may be asymptomatic or affect people at a variable extent. Since they often represent chronic conditions their prevalence increases by age and reaches in elderly the highest rates. Thyroid nodules are a common clinical finding. Most subjects with thyroid nodules have few or no symptoms. Thyroid nodules are more commonly non-functioning. However, in elderly, toxic multinodular goiter is the most frequent cause of spontaneous hyperthyroidism and often, it emerges insidiously from nontoxic multinodular goiter. Although autoimmune thyroiditis is the most common cause of hypothyroidism in elderly subjects, other causes, such as drugs, neck radiotherapy, thyroidectomy or radioiodine therapy, are frequently observed among these subjects. A small subset of medications including dopamine agonists, glucocorticoids and somatostatin analogs affect thyroid function through suppression of TSH. Other medications that may affect TSH levels are metformin, antiepileptic medications, lithium carbonate and iodine-containing medications. Other drugs can alter T4 absorption, T4 and T3 transport in serum and metabolism of T4 and T3, such as proton-pump inhibitors and antacids, estrogens, mitotane and fluorouracil, phenobarbital and rifampin. Amiodarone administration is associated with thyrotoxicosis or hypothyroidism. Thyroid cancer has similar characteristics in elderly as in general population, however the rate of aggressive forms such as the anaplastic histotype, is higher in older than younger subjects. Diagnosis of thyroid diseases includes a comprehensive medical history and physical examination and appropriate laboratory tests. A correct diagnosis of thyroid diseases in the elderly is crucial for proper treatment, which consists in the removal of medications that may alter thyroid function, in the use of levo-thyroxine in case of hypothyroidism, anti-thyroid drugs in case of hyperthyroidism and use of surgery, radioiodine therapy and percutaneous ablative procedures in selected cases. In conclusion, thyroid diseases in patients older than 60 years deserve attention from different points of view: the prevalence is different from the young adult; symptoms are more nuanced and makes difficult the diagnosis; age and comorbidity often force therapeutic choices and may limit safety and efficacy of therapy. Finally, in elderly patients for whom specific therapy is necessary, more gradual and careful therapeutic approach and close follow-up are recommended in order to minimize the alterations of thyroid function which are induced by many drugs commonly used in clinical practice
Predictive factors of response to mTOR inhibitors in neuroendocrine tumours.
No full textMedical treatment of neuroendocrine tumours has drawn a lot of attention due to the recent demonstration of efficacy of several drugs on progression free survival, including somatostatin analogs, small tyrosine kinase inhibitors and mTOR inhibitors (or rapalogs). The latter are approved as therapeutic agents in advanced pancreatic neuroendocrine tumors and have been demonstrated to be effective in different types of neuroendocrine tumors, with variable efficacy due to the development of resistance to treatment. Early detection of patients that may benefit from rapalogs treatment is of paramount importance in order to select the better treatment and avoid ineffective and expensive treatments. Predictive markers for therapeutic response are under intensive investigation, aiming at a tailored patient management and more appropriate resource utilization. This review summarizes the available data on the tissue, circulating and imaging markers that are potentially predictive of rapalog efficacy in neuroendocrine tumours
- …
