ITALIANO: Gli Autori hanno impiegato il Fazadinio bromuro durante l'anestesia del cane, ottenendo buoni risultati e constatando l'assenza di significativi effetti collaterali e la sua buona ...maneggevolezza.
Semiconductor optical amplifiers (SOAs) are becoming key elements of modern communication systems, particularly in view of optical signal processing. The carrier dynamics in the gain medium can be ...exploited to implement all-optical wavelength conversion, demultiplexing, clock-recovery and signal regeneration. Furthermore, SOAs can be integrated with waveguides to form compact and polarization-insensitive functional devices. In this contribution we present a very compact Michelson interferometer, obtained by monolithic integration of two SOAs with a passive waveguide section, incorporating turning mirrors. It operates in the 1550 nm window. Based on the cross-phase modulation effect, taking place in the SOAs under optical pumping, we used our device to obtain wavelength conversion to wavelengths either longer or shorter than the pump wavelength.
Two types of spongy polyurethane-polydimethylsiloxane (PU-PDMS) vascular grafts (1.5 mm ID, 450 microns wall thickness) were fabricated with either a skinned (SG) or a porous (PG) luminal surface and ...an open mesh filamentous external surface by a spraying, phase-inversion technique. Tubular membranes, 15-20 mm in length, were all implanted by the same surgeon as infrarenal aorta replacements in male Sprague-Dawley rats weighing 250-350 g (SG: n = 12, PG: n = 23). The patency rates at 2 weeks and 3 months were 0% (0/7) and 0% (0/1) for SG, 72% (8/11) and 8% (1/12) for PG. Because the wall structure of these grafts was relatively compact and did not provide enough communicating voids, another series of 15 highly porous luminal surface grafts was fabricated with a higher void to material ratio. These grafts (HPG) exhibited a 73% patency at 3 months, with a fully endothelialized surface. The authors conclude that a very open luminal surface structure, and a high wall porosity, are significant factors of graft patency in small diameter vascular prostheses made of a porous material.
The Authors refer the good results obtained in the clinical use of Medetomidine and of its specific antagonist (MPV 1248) able to displace completely the sedative-analgetic effects of Medetomidine.
...ITALIANO: Gli Autori riferiscono i buoni risultati ottenuti impiegando clinicamente la Medetomidina ed il suo specifico antagonista (MPV 1248) capace di spiazzare completamente gli effetti sedativo-analgesici della Medetomidina.
Ketamine exhibited effects on gastric acid secretion total acidity and acid output. Reduction of secretion by ketamine did not appe,r to be significantly different from values obtained with atropine ...or hexamethonium. In addition to atropine- and hexamethonium-like effects, ketamine also appeared to decrease gastric secretion through a potentiating activity on the sympathetic nervous system. When sympathetic activity was potentiated by cocaine, the antisecretory effect of ketamine appeared to be significantly reduced, compared with that of atropine. Furthermore, after alpha- or alpha- and beta-blockade, ketamine produced similar decreases in secretion, although maximum inhibitory effect was obtained after beta-blockade. Potentiation of adrenergic activity by ketamine seemed to be mediated through alpha-receptors. Histamine H2 receptors did not appear to be involved in the antisecretory action of ketamine.
The pharmacokinetics of thiamphenicol (TAP) was investigated in preruminant calves after intravenous and oral (in a milk solution) administration at a dose of 30 mg/kg. TAP plasma concentrations were ...evaluated by HPLC on blood samples collected over 24 h following treatment. TAP kinetic profile after intravenous administration was characterized by a rapid and wide distribution. The half-life was 3.76+-0.13 h and the concentration at the last time (24 h) 0.12+-0.03 microng/ml. After oral dose, a Cmax of 3.70+-0.89 microng/ml was reached at 5.5 h. T1/2beta was 6.84 h and the oral bioavailability was 62%, It is concluded that oral administration of TAP to pre-ruminant calves provides therapeutically effective plasma drug concentrations up to 24 h after treatment. The oral bioavailability of TAP was considerably higher than that reported for adult ruminants. These results suggest that in pre-ruminant calves the abomasal delivery of the drug due to closure of the esophageal groove avoids rumino-reticular dispersion and reduces the first-pass metabolism responsible for the low oral bioavailability of TAP in adult ruminants
In vitelli pre-ruminanti e' stata studiata la farmacocinetica del tiamfenicolo (TAP) a seguito di somministrazione per via intravenosa e orale (in una soluzione di latte), alla dose di 30 mg/kg. Le concentrazioni plasmatiche di TAP sono state valutate mediante HPLC su campioni di sangue prelevati per un periodo di 24 h dopo il trattamento. Il profilo cinetico dopo la somministrazione intravenosa era caratterizzato da un'ampia e rapida distribuzione. Il tempo di semivita era pari a 3.76+-0.13 h e la concentrazione alla fine del periodo (24 h) risultava di 0.12+-0.03 microng/ml. Dopo la somministrazione orale la concentrazione plasmatica picco di 3.70+-0.89 microng/ml era raggiunta a 5.5 h; la semivita era di 6.84 h e la biodisponibilita' orale era pari al 62%. Si conclude che la somministrazione orale di TAP ai vitelli pre-ruminanti fornisce concentrazioni plasmatiche del farmaco efficaci terapeuticamente fino a 24 h dopo il trattamento. La biodisponibilita' orale di TAP era considerevolmente maggiore rispetto a quella riportata per ruminanti adulti. Questi risultati fanno ritenere che nei vitelli pre-ruminanti la destinazione abomasale del farmaco dovuta alla chiusura della doccia esofagea eviti la dispersione rumino-reticolare e riduca il metabolismo di primo passaggio del farmaco responsabile della biodisponibilita' orale bassa di TAP nei ruminanti adulti
