1,720,958 research outputs found
Bone alkaline phosphatase measured with a new immunoradiometric assay in patients with metabolic bone diseases
No full textWe have investigated the clinical utility of a new quantitative two-site radioimmunometric assay specific for bone alkaline phosphatase (B-ALP) in 219 healthy control subjects and in 264 patients with various metabolic bone diseases. B-ALP was compared with total alkaline phosphatase (T-ALP) and with osteocalcin (BGP). B-ALP increased linearly with age in both sexes. In postmenopausal normal women B-ALP increased by 82% compared with premenopausal normal women, whereas the differences between pre- and postmenopausal women for T-ALP and BGP were 18% and 30% respectively. As assessed by Z-score, the highest values of B-ALP were found in patients with Paget's disease of bone, bone metastases or hyperparathyroidism and in patients on maintenance haemodialysis. In osteoporotic patients, B-ALP< but not T-ALP, showed a slight but significant (P < 0.05) difference compared with normal women. On the basis of bone turnover, osteoporotic patients were divided into two groups: high turnover and low turnover; B-ALP, like BGP, was significantly (P < 0.01) higher in patients with high turnover. In conclusion, B-ALP, measured by this new method, can be considered a sensitive marker of bone turnover and could be especially useful in identifying women at risk of developing osteoporosi
Graphic trace analysis of ultrasound at the phalanges may differentiate between subjects with primary hyperparathyroidism and with osteoporosis: a pilot study
No full textBone loss characterizes both primary hyperparathyroidism (PHPT) and osteoporosis (OP) but with a different histologic pattern, and this could partially explain the different fracture incidence in these two populations. Quantitative ultrasound (QUS), influenced by bone structural parameters other than bone mineral density (BMD), could evidence these differences, opening new perspectives in the evaluation of patients with metabolic bone diseases. The aim of the present study was to investigate the usefulness of QUS graphic trace parameters, assessed at the phalanx, in discriminating between PHPT bone disease and osteoporosis. We studied 34 patients with PHPT (mean age 59.7 +/- 12.7 years), 35 patients with OP (mean age 60.6 +/- 7.1 years) and 34 healthy subjects as controls (mean age 59.1+/- 9.4 years). In all subjects QUS measurements were performed at the phalanx with a Bone Profiler (IGEA, Italy), obtaining the amplitude-dependent speed of sound (AD-SoS), fast wave amplitude (FWA), signal dynamic (SDy), bone transmission time (BTT) and ultrasound bone profile index (UBPI). Moreover, serum calcium, phosphorus, parathyroid hormone (PTH), bone isoenzyme of alkaline phosphatase (B-ALP) and ionized calcium were measured in all subjects in the morning under fasting conditions. In PHPT patients BTT was correlated with PTH, ionized calcium and B-ALP levels (r = -0.47, -0.57 and -0.44, respectively; p < 0.01), whereas FWA, SDy and UBPI correlated only with B-ALP (r = -0.43, -0.46 and -0.50, respectively; p <0.01). Moreover, FWA, SDY and UBPI were significantly (p<0.01) lower and BTT significantly (p<0.001) higher in OP than in PHPT patients. UBPI, BTT, FWA and the BTT/FWA ratio, but not SDy, were able to discriminate between the two groups (area under the curve =0.66, 0.69, 0.67 and 0.81, respectively). Our findings show that ultrasound signal parameters are differently influenced by bone changes characterizing primary hyperparathyroidism or osteoporosis. This suggests that the QUS signal could be a useful instrument in discriminating and studying some of the bone alterations typical of metabolic bone diseases
Changes in serum HDL and LDL cholesterol in patients with Paget's bone disease treated with pamidronate
No full textAmino bisphosphonates represent one of the most important advances in the management of Paget's and other metabolic bone diseases. Although their mechanism of action has not yet been completely clarified, they seem to inhibit the mevalonate pathway and so they could interfere with cholesterol synthesis. The present study aimed to evaluate cholesterol and lipoprotein serum levels in patients with Paget's bone disease treated with intravenous pamidronate. The study included 20 consecutive patients (mean age, 67.6 +/- 11.0 years) with Paget's bone disease for at least 1 year, who needed intravenous amino bisphosphonate treatment; 12 patients with inactive Paget's bone disease served as controls. The patients with active Paget's bone disease underwent three cycles (every 3 months) of treatment with 60 mg of intravenous pamidronate. Controls were given a saline infusion following the same administration schedule. In all subjects total alkaline phosphatase (total ALP), bone alkaline phosphatase (bone ALP), total cholesterol (TC), tryglycerides (TG), and high- and low-density lipoprotein cholesterol (HDL-C and LDL-C, respectively) were measured before infusions (pamidronate or saline) at baseline and at 3-month intervals up to 9 months. In the control group no significant changes were observed through the study period for any of the biochemical parameters. In the pamidronate-treated patients, both bone ALP and total ALP significantly fell at the end of the study. In patients with active treatment, at the end of the study period HDL-C significantly (P < 0.05) increased by 10.3%, whereas LDL-C significantly (P < 0.05) decreased by 5.5%. In these patients TC showed a negative trend without reaching statistical significance, whereas the HDL-C/LDL-C ratio rose 16.2% above the basal value and TC/HDL-C decreased by 12.5%. In conclusion, pamidronate given intravenously seems to be able to induce a prolonged shifting in circulating cholesterol from the LDL-C to the HDL-C from associated with a weak decrease in total cholesterol, thus producing a possible improvement in the atherosclerotic risk index
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
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
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