1,721,045 research outputs found
Targeting the sarcolemmal calcium pump: a potential novel strategy for the treatment of cardiovascular disease.
No full textpeer reviewedIntracellular calcium dynamics play a very important role in mediating contraction and signalling in cardiomyocytes and vascular smooth muscle cells. A number of calcium transporters have been identified that orchestrate a complex process of excitation-contraction coupling and molecular signalling. Despite the variability of the calcium transporters expressed in cardiomyocytes, most calcium channel blockers used therapeutically target the L-type calcium channel and exhibit antihypertensive and/or vasodilating activities. Recently, another calcium pump which is located in the sarcolemma has been shown to mediate cardiac contractility and vascular tone. Interestingly, this sarcolemmal calcium pump (also known as Plasma Membrane Calcium/calmodulin dependent ATPase or PMCA) exerts its function not by altering global calcium concentration, but by mediating signal transduction pathways. This review will discuss recent advances that support the key roles of PMCA as signalling molecule and the potential to target this calcium pump as a novel approach for the treatment of cardiovascular disease
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
Physiological implications of the interaction between the plasma membrane calcium pump and nNOS.
No full textpeer reviewedThe tight regulation of intracellular calcium levels is essential for the normal function of a great many cellular processes, and disruption of this regulation, resulting in sustained increases in intracellular-free calcium, has been associated with numerous diseases. One of the several transporters involved in calcium homeostasis is a P-type ATPase known as the plasma membrane calcium/calmodulin-dependent ATPase (PMCA) which is involved in calcium extrusion from the cytosol to the extracellular compartment. It has long been established that in many cell types, in particular non-excitable cells, the primary role of PMCA is in the bulk transport of intracellular calcium; however, its role in excitable cells is less clear. In the heart, for example, calcium is essential for contractile function as well as being a key messenger in signal transduction pathways; however, the mechanisms by which the cardiomyocyte distinguishes between these roles of calcium remain unclear. It is perhaps the transporters not involved in the contractile cycle (such as PMCA) that are able to carry non-contractile signals. This review will highlight the role of PMCA as a modulator of signal transduction pathways and in particular the role of isoform 4 in the regulation of the nitric oxide signalling pathway
Kelainan Peak Expiratory Flow Rate Dibandingkan dengan Keluhan Sistim Pernapasan – studi pada 75 anggota pasukan kuning, Surabaya
Full text linkTelah dilakukan kajian untuk membandingkan hasil pemeriksaan faal paru Peak Expiratory Flow Rate (PEFR) dalam mendeteksi kelainan paru obstruktif dengan anamnesis adanya keluhan batuk, pengeluaran dahak, sesak nafas dan nafas berbunyi. Sebagai subyek penelitian adalah anggota pasukan kuning Kotamadya Surabaya yang bertugas di jalan raya sebanyak 75 orang. Dipilih anggota pasukan kuning karena dalam melaksanakan tugas sehari-hari diduga mendapat pemaparan polusi debu dan gas buang kendaraan bermotor. Hasil yang didapat adalah proporsi kelainan PEFR secara keseluruhan sebesar 42,67%, di antara yang mengeluh keluhan batuk sebesar 24,00%, di antara yang mengeluarkan dahak sebesar 14,67%, di antara yang sesak nafas sebesar 22,67% dan di antara yang nafasnya berbunyi sebesar 10,67%.
Ternyata didapatkan hubungan antara kelainan faal paru PEFR dengan adanya keluhan batuk (p = 0,0216), dengan keluhan pengeluaran dahak (p = 0,0005), dengan keluhan sesak nafas (p = 0,018) dan dengan keluhan nafas berbunyi (p = 0,0000). Subyek dengan kelainan faal paru PEFR tanpa keluhan berkisar antara 30,67 –36% dari seluruh subyek yang diperiksa
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
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