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Effetti in vitro di beta-endorfina e naloxone sulla concentrazione intracellulare di calcio in cellule della granulosa murale equina
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A semi-immobilizing system associated with microspectroflurimetric and videoimaging analysis for intracytoplasmic calcium measurement in individual viable spermatozoa
No full textWe describe a fast and simple method to monitor variations of intracytoplasmic calcium concentrations in very small and motile cells such as
mammalian spermatozoa during measurement time. The method combines a procedure of sperm cells semi-immobilization with microspectrofluorimetric
measurement of intracytoplasmic calcium concentrations supported by videoimaging that allows also a constant monitoring of viability
during the time of calcium recording. In this paper we show that a semi-immobilization of individual viable spermatozoa can be obtained preparing
the agar matrix in a two step procedure. The cell immobilizing system proposed, associated with the microspectrofluorimetric analysis supported
by videoimaging, is a simple, rapid and useful tool for those studies having the goal of correlating the presence and cellular distribution of ion
channels with their functional status and their response to physiologic and/or pharmacological molecules
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
Un sistema di semi-immobilizzazione in matrice di agar per analisi microspettrofluorimetrica delle variazioni di [Ca2+]i in singoli spermatozoi
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Stress-related hormones in horses before and after stunning by captive bolt gun
No full textIn this work the slaughter-linked plasma modifications of some stress-related hormones in horses subject to standardized butchering procedures were investigated in order to highlight the compromised animal welfare during pre-slaughter handling. During pre-slaughter, animals show strong hardship behavioural patterns, probably due to being under life-threatening conditions. Blood samples from 12 male horses, ageing from 3 to 5 years, were collected before slaughtering in lairage, and during exsanguination after stunning. Catecholamines, cortisol and beta-endorphin concentrations were assessed in plasma samples by EIA. Results show that plasma beta-endorphin concentration did not increase significantly after stunning, while cortisol (P < 0.05) and catecholamines (P < 0.001) increased significantly. The ratio between the plasma level of norepinephrine and epinephrine decreased significantly (P < 0.001) during the time considered for observation underlining a greater involvement of adrenal medulla in the stress response. Moreover these results suggest that, under stress, the release of beta-endorphin could be different from that of ACTH. (C) 2009 Elsevier Ltd. All rights reserved
Studio sulle variazioni di [Ca2+]i in singoli spermatozoi bovini con tecniche di microspettrofluorimetria
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