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Consistency of nephron filtration measurements by collection of tubular total fluid from different proximal sites
No full textEur J Appl Physiol Occup Physiol. 1997;76(5):389-93.
Consistency of nephron filtration measurements by collection of total tubular fluid from different proximal sites.
Romano G, Damato R, Favret G, Bartoli E.
SourceDepartment of Internal Medicine, DPMSC, University of Udine, Medical School, Italy.
Abstract
The stability of single nephron glomerular filtration rate (SNGFR) is assured by specific mechanisms such as the tubulo-glomerular feedback system and autoregulation. Studies on renal physiology rely heavily on the measurements of SNGFR, which are feasible only in animals. The measurement of SNGFR by collection of total tubular fluid may be influenced by the fall in intratubular hydrostatic pressure that may reflect the negative pressure applied to the sampling pipette. This effect may become more important with shortening of the distance between the sampling site and the Bowman space. We analysed this putative effect by performing collections of total tubular fluid from the late proximal (LP), and then from the early proximal (EP) segment of the same nephrons. In 128 paired collections LP-SNGFR averaged 35 (SEM 2) nl x min(-1), and was no different from the paired mean EP-SNGFR of 37 (SEM 2) nl x min(-1), P > 0.179. Then EP- and LP- SNGFR were significantly correlated (r = 0.77, P < 0.001). As expected, the respective paired means of absolute and percentage reabsorptions, and those of collection rates were significantly different. The average SNGFR computed from each LP and EP paired measurement was significantly correlated with the simultaneously measured kidney glomerular filtration rate, GFR (r = 0.60, P < 0.0001). The ratio of GFR to SNGFR indicated the expected number of glomeruli. These data would indicate that the sampling site does not influence the measurement of SNGFR in the proximal tubule when the total fluid collection technique is correctly performed. They also exclude a time-dependent activation of the macula densa capable of upregulating SNGFR within the interval elapsing between the beginning of LP and the completion of EP collections, which in our study averaged 4.4 (SEM 0.1) min
Visualization of effects of ET-A receptor blockade with BQ-123 on renal hemodynamics in the split hydronephrotic kidneys of rats
No full textVolume receptors in guinea pig labyrinth: relevance with respect to ADH and sodium control
No full textSebastiano Bartoli e il «Breve ragguaglio de’ Bagni di Pozzuolo»
No full textAntonio Pietro d'Aragona, viceré di Napoli, nel suo programma politico aveva previsto grandi opere pubbliche, compreso il restauro delle antiche terme dei Campi Flegrei. Nel 'Breve ragguaglio de Bagni di Pozzuolo' Sebastiano Bartoli riporta il racconto di questo recupero con un ulteriore scopo, quello di promuovere le terme mostrandone gli aspetti singolari. Da questo studio emerge la metodologia utilizzzata da Bartoli nella 'constitutio textus' e le fonti da lui utilizzate. Si tratta di testi appartenenti alla tradizione letteraria, tra i quali 'Le antichita` di Pozzuolo et luoghi convicini' di Ferrante Loffredo, 'De balneis Terrae Laboris' di Alcadino Siculo (poi identificato come Pietro da Eboli) e 'Croniche de la inclyta cita` de Napole emendatissime, con li bagni di Puzolo e Ischia nuovamente ristampate' attribuito a Giovanni Villani
Sebastiano Bartoli e la cultura termale del suo tempo
No full textIl volume porta un originale contributo su Sebastiano Bartoli e le sue opere scientifiche con particolare attenzione a quelle termali. Medico e professore di medicina a Napoli, il Bartoli nacque a Montella nel 1630 e morì a Napoli nel 1667. Fu membro dell'Accademia degli Investiganti. Nella sua opera, la "Thermologia aragonia", Bartoli esamina ed illustra i singoli luoghi termali dimostrando anche di possedere una solida cultura classica.
Alla figura del Bartoli sono dedicati in questo volume saggi che ne ricostruiscono la personalità intellettuale nel più ampio quadro del termalismo napoletano del secolo XVII e della cultura filosofica del momento
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
Clinical assessment of renal vascular involvement and clinical-pathological correlations
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