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81.
F. Trischitta M. G. Denaro C. Faggio 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1999,169(6):370-376
The effects of acetylcholine analogues, serotonin and catecholamines on ion transport were studied in both the middle and
the posterior intestine of Anguilla anguilla, mounted in an Ussing chamber, with the aim of understanding whether these regulators affect different mechanisms in the
different tracts. In the middle intestine, acetylcholine analogues and serotonin decreased the serosa negative transepithelial
potential and short-circuit current without altering the transepithelial resistance; catecholamines reversed the inhibitory
effects of both regulators. Similar opposite effects were produced by both the acetylcholine analogues and noradrenalin in
the posterior intestine. However, the lowering of the short-circuit current elicited by serotonin was paralleled by the decrease
of the transepithelial resistance, whilst noradrenalin had the opposite effects on both parameters. These observations, together
with the results of experiments performed by measuring the dilution potential in the control condition and in the presence
of either serotonin or serotonin plus noradrenalin, led us to hypothesize that serotonin increases the anion conductance of
the paracellular pathway while noradrenalin decreases it. In both the middle and posterior intestine, these regulators probably
affect transcellular transport mechanisms by acting on the Na-K-Cl transporter; both acetycholine and serotonin decrease its
activity while noradrenalin increases it.
Accepted: 22 May 1999 相似文献
82.
M. Genovese R. Denaro S. Cappello G. Di Marco G. La Spada L. Giuliano L. Genovese M.M. Yakimov 《Journal of applied microbiology》2008,105(5):1694-1702
Aims: In this study, we evaluated the removal efficiency of fuel hydrocarbons from a jet fuel contaminated area using bioaugmentation treatment in biopile. Methods and Results: The hydrocarbon analysis of the sample revealed total hydrocarbons mainly constituted by benzene, toluene, ethylbenzene, xylenes (BTEX) and heavy aliphatic hydrocarbons. Enrichments of soil sample were performed with BTEX, pristane and fuel JP-5, respectively, selected hydrocarbon-degrading strains, namely Acinetobacter sp., Pseudomonas sp. and Rhodococcus sp. Three hundred litres of culture containing 108 cell ml−1 of each strain and nutrients sprayed on the biopile allowed a removal of 90% of total hydrocarbons in 15 days. Bioremediation process was monitored by observation of the respiration rate and the bacterial abundance and GC-MS analysis. Conclusions: The efficiency of the treatment in the biopile was considerable. The assessment of microbial activity during the experiment is necessary for interventions targeted to improve environmental parameters such as humidity, temperature, pH and nutrients for optimization of the bioremediation process. Significance and Impact of the Study: A better knowledge of microbial successions at oil-polluted sites is essential for environmental bioremediation. Data obtained in biopile study improve our understanding of processes occurring during oil pollution. 相似文献
83.
A Salleo G Anastasi G La Spada M G Denaro G Falzea L Magaudda 《Differentiation; research in biological diversity》1979,15(2):119-125
Muscle fibrillation has been suggested as a possible trigger for activation of satellite cells, a well known phenomenon associated with denervation. In order to test such a hypothesis fibrillation has been induced in normally innervated muscles by chronic administration of neostigmine and the response of satellite cells has been observed with a scanning electron microscope. The results show that satellite cells protrude from the profile of the muscle fiber, become partially separated from the latter, and align in rows. Elongated structures and presumable new muscle fibers are observed after 14 days of treatment. It is concluded that the overactivity of muscle fibers which is induced during fibrillation causes activation and differentiation of satellite cells. This result is consistent with that of a previous experiment showing that satellite cells are activated during acute increase in workload. 相似文献
84.
Arakkaveettil Kabeer Farha Thasneem TR Aswathy Purushothaman Jaseetha Abdul Salam Abdulla Mohamed Hatha 《Journal of Genetic Engineering and Biotechnology》2018,16(2):253-258
Marine environments are substantially untapped source for the isolation of bacteria with the capacity to produce various extracellular hydrolytic enzymes, which have important ecological roles and promising biotechnological applications. Hydrolases constitute a class of enzymes widely distributed in nature from bacteria to higher eukaryotes. Marine microbial communities are highly diverse and have evolved during extended evolutionary processes of physiological adaptations under the influence of a variety of ecological conditions and selection pressures. A number of marine hydrolases have been described, including amylases, lipases and proteases, which are being used extensively for biotechnological applications. The present study was carried out to isolate marine bacteria from continental slope sediments of the eastern Arabian Sea and explore their biotechnological potential. Among the 119 isolates screened, producers of amylases (15%), caseinases (40%), cellulases (40%), gelatinases (60%), lipases (26%), ligninases (33%), phytase (11%) and Malachite Green dye degraders (16%) were detected. Phylogenetic analysis based on 16S rRNA gene sequencing showed that predominant marine sediment bacteria possessing more than four enzymatic activities belonged to the phyla Firmicutes and Proteobacteria, was assigned to the genera Bacillus, Planococcus, Staphylococcus, Chryseomicrobium, Exiguobacterium and Halomonas. Biodegradation of the dye Malachite Green using the liquid decolorization assay showed that both the individual cultures (Bacillus vietnamensis, Planococcus maritimus and Bacillus pumilus) and their consortium were able to decolorize more than 70% of dye within 24?h of incubation. This is the first report on diversity and extracellular hydrolytic enzymatic activities and bioremediation properties of bacteria from continental slope sediment of eastern Arabian Sea. 相似文献
85.
86.
A simple equipment was developed to cultivate young cereal plants under enhanced CO2 concentration. Cultivation system permits growing of about 40 barley seedlings for about 2 to 3 weeks. The system consists
of two identical growth chambers (volume about 30 dm3), gas conditioning circuit and measuring circuit with an infra-red CO2 analyser. Capabilities of the whole equipment were tested by growing barley plants under 330 and 1000 cm3 (CO2)m−3 and in combination with high or low nitrate level. 相似文献
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